Merge pull request #57600 from thockin/vendor-gazelle

Automatic merge from submit-queue. If you want to cherry-pick this change to another branch, please follow the instructions <a href="https://github.com/kubernetes/community/blob/master/contributors/devel/cherry-picks.md">here</a>.

Vendor gazelle and kazel

Rather that relying on upstream git repos that can break, vendor it all.  These are NOT head of tree, respectively - they are some backrev forms that were previously being used.

```release-note
NONE
```

Godeps/Godeps.json

@@ -7,6 +7,8 @@
 		"github.com/jteeuwen/go-bindata/go-bindata",
 		"github.com/tools/godep",
 		"github.com/client9/misspell/cmd/misspell",
+		"github.com/bazelbuild/bazel-gazelle/cmd/gazelle",
+		"github.com/kubernetes/repo-infra/kazel",
 		"./..."
 	],
 	"Deps": [
@@ -310,6 +312,71 @@
 			"Comment": "v1.12.7",
 			"Rev": "760741802ad40f49ae9fc4a69ef6706d2527d62e"
 		},
+		{
+			"ImportPath": "github.com/bazelbuild/bazel-gazelle/cmd/gazelle",
+			"Comment": "0.10.1",
+			"Rev": "ff4d67f395b3f4d1dc9810eeceb61585fea252cb"
+		},
+		{
+			"ImportPath": "github.com/bazelbuild/bazel-gazelle/internal/config",
+			"Comment": "0.10.1",
+			"Rev": "ff4d67f395b3f4d1dc9810eeceb61585fea252cb"
+		},
+		{
+			"ImportPath": "github.com/bazelbuild/bazel-gazelle/internal/label",
+			"Comment": "0.10.1",
+			"Rev": "ff4d67f395b3f4d1dc9810eeceb61585fea252cb"
+		},
+		{
+			"ImportPath": "github.com/bazelbuild/bazel-gazelle/internal/merger",
+			"Comment": "0.10.1",
+			"Rev": "ff4d67f395b3f4d1dc9810eeceb61585fea252cb"
+		},
+		{
+			"ImportPath": "github.com/bazelbuild/bazel-gazelle/internal/packages",
+			"Comment": "0.10.1",
+			"Rev": "ff4d67f395b3f4d1dc9810eeceb61585fea252cb"
+		},
+		{
+			"ImportPath": "github.com/bazelbuild/bazel-gazelle/internal/pathtools",
+			"Comment": "0.10.1",
+			"Rev": "ff4d67f395b3f4d1dc9810eeceb61585fea252cb"
+		},
+		{
+			"ImportPath": "github.com/bazelbuild/bazel-gazelle/internal/repos",
+			"Comment": "0.10.1",
+			"Rev": "ff4d67f395b3f4d1dc9810eeceb61585fea252cb"
+		},
+		{
+			"ImportPath": "github.com/bazelbuild/bazel-gazelle/internal/resolve",
+			"Comment": "0.10.1",
+			"Rev": "ff4d67f395b3f4d1dc9810eeceb61585fea252cb"
+		},
+		{
+			"ImportPath": "github.com/bazelbuild/bazel-gazelle/internal/rules",
+			"Comment": "0.10.1",
+			"Rev": "ff4d67f395b3f4d1dc9810eeceb61585fea252cb"
+		},
+		{
+			"ImportPath": "github.com/bazelbuild/bazel-gazelle/internal/version",
+			"Comment": "0.10.1",
+			"Rev": "ff4d67f395b3f4d1dc9810eeceb61585fea252cb"
+		},
+		{
+			"ImportPath": "github.com/bazelbuild/bazel-gazelle/internal/wspace",
+			"Comment": "0.10.1",
+			"Rev": "ff4d67f395b3f4d1dc9810eeceb61585fea252cb"
+		},
+		{
+			"ImportPath": "github.com/bazelbuild/buildtools/build",
+			"Comment": "0.6.0-60-g1a9c38e",
+			"Rev": "1a9c38e0df9397d033a1ca535596de5a7c1cf18f"
+		},
+		{
+			"ImportPath": "github.com/bazelbuild/buildtools/tables",
+			"Comment": "0.6.0-60-g1a9c38e",
+			"Rev": "1a9c38e0df9397d033a1ca535596de5a7c1cf18f"
+		},
 		{
 			"ImportPath": "github.com/beorn7/perks/quantile",
 			"Rev": "3ac7bf7a47d159a033b107610db8a1b6575507a4"
@@ -2018,6 +2085,10 @@
 			"ImportPath": "github.com/kr/text",
 			"Rev": "6807e777504f54ad073ecef66747de158294b639"
 		},
+		{
+			"ImportPath": "github.com/kubernetes/repo-infra/kazel",
+			"Rev": "2a736b4fba317cf3038e3cbd06899b544b875fae"
+		},
 		{
 			"ImportPath": "github.com/libopenstorage/openstorage/api",
 			"Rev": "093a0c3888753c2056e7373183693d670c6bba01"
@@ -2428,15 +2499,10 @@
 			"ImportPath": "github.com/pborman/uuid",
 			"Rev": "ca53cad383cad2479bbba7f7a1a05797ec1386e4"
 		},
-		{
-			"ImportPath": "github.com/pelletier/go-buffruneio",
-			"Comment": "v0.1.0",
-			"Rev": "df1e16fde7fc330a0ca68167c23bf7ed6ac31d6d"
-		},
 		{
 			"ImportPath": "github.com/pelletier/go-toml",
-			"Comment": "v0.3.5-10-g0049ab3",
-			"Rev": "0049ab3dc4c4c70a9eee23087437b69c0dde2130"
+			"Comment": "v1.0.1",
+			"Rev": "16398bac157da96aa88f98a2df640c7f32af1da2"
 		},
 		{
 			"ImportPath": "github.com/peterbourgon/diskv",

api/BUILD

@@ -1,18 +0,0 @@
-package(default_visibility = ["//visibility:public"])
-
-filegroup(
-    name = "package-srcs",
-    srcs = glob(["**"]),
-    tags = ["automanaged"],
-    visibility = ["//visibility:private"],
-)
-
-filegroup(
-    name = "all-srcs",
-    srcs = [
-        ":package-srcs",
-        "//api/openapi-spec:all-srcs",
-        "//api/swagger-spec:all-srcs",
-    ],
-    tags = ["automanaged"],
-)

build/root/BUILD.root

@@ -58,7 +58,8 @@ filegroup(
     name = "all-srcs",
     srcs = [
         ":package-srcs",
-        "//api:all-srcs",
+        "//api/openapi-spec:all-srcs",
+        "//api/swagger-spec:all-srcs",
         "//build:all-srcs",
         "//cluster:all-srcs",
         "//cmd:all-srcs",

hack/godep-save.sh

@@ -59,6 +59,8 @@ REQUIRED_BINS=(
   "github.com/jteeuwen/go-bindata/go-bindata"
   "github.com/tools/godep"
   "github.com/client9/misspell/cmd/misspell"
+  "github.com/bazelbuild/bazel-gazelle/cmd/gazelle"
+  "github.com/kubernetes/repo-infra/kazel"
   "./..."
 )
 

hack/lib/util.sh

@@ -436,12 +436,19 @@ kube::util::ensure_godep_version() {
 
   kube::log::status "Installing godep version ${GODEP_VERSION}"
   go install ./vendor/github.com/tools/godep/
-  GP="$(echo $GOPATH | cut -f1 -d:)"
-  hash -r # force bash to clear PATH cache
-  PATH="${GP}/bin:${PATH}"
+  if ! which godep >/dev/null 2>&1; then
+    kube::log::error "Can't find godep - is your GOPATH 'bin' in your PATH?"
+    kube::log::error "  GOPATH: ${GOPATH}"
+    kube::log::error "  PATH:   ${PATH}"
+    return 1
+  fi
 
   if [[ "$(godep version 2>/dev/null)" != *"godep ${GODEP_VERSION}"* ]]; then
-    kube::log::error "Expected godep ${GODEP_VERSION}, got $(godep version)"
+    kube::log::error "Wrong godep version - is your GOPATH 'bin' in your PATH?"
+    kube::log::error "  expected: godep ${GODEP_VERSION}"
+    kube::log::error "  got:      $(godep version)"
+    kube::log::error "  GOPATH: ${GOPATH}"
+    kube::log::error "  PATH:   ${PATH}"
     return 1
   fi
 }
@@ -467,23 +474,6 @@ kube::util::ensure_no_staging_repos_in_gopath() {
   fi
 }
 
-# Installs the specified go package at a particular commit.
-kube::util::go_install_from_commit() {
-  local -r pkg=$1
-  local -r commit=$2
-
-  kube::util::ensure-temp-dir
-  mkdir -p "${KUBE_TEMP}/go/src"
-  GOPATH="${KUBE_TEMP}/go" go get -d -u "${pkg}"
-  (
-    cd "${KUBE_TEMP}/go/src/${pkg}"
-    git checkout -q "${commit}"
-    GOPATH="${KUBE_TEMP}/go" go install "${pkg}"
-  )
-  PATH="${KUBE_TEMP}/go/bin:${PATH}"
-  hash -r # force bash to clear PATH cache
-}
-
 # Checks that the GOPATH is simple, i.e. consists only of one directory, not multiple.
 kube::util::ensure_single_dir_gopath() {
   if [[ "${GOPATH}" == *:* ]]; then

hack/update-bazel.sh

@@ -26,13 +26,14 @@ kube::util::ensure-gnu-sed
 # TODO(spxtr): Remove this line once Bazel is the only way to build.
 rm -f "${KUBE_ROOT}/pkg/generated/openapi/zz_generated.openapi.go"
 
-# The git commit sha1s here should match the values in $KUBE_ROOT/WORKSPACE.
-kube::util::go_install_from_commit \
-    github.com/kubernetes/repo-infra/kazel \
-    97099dccc8807e9159dc28f374a8f0602cab07e1
-kube::util::go_install_from_commit \
-    github.com/bazelbuild/bazel-gazelle/cmd/gazelle \
-    0.10.1
+# Ensure that we find the binaries we build before anything else.
+export GOBIN="${KUBE_OUTPUT_BINPATH}"
+PATH="${GOBIN}:${PATH}"
+
+# Install tools we need, but only from vendor/...
+go install ./vendor/github.com/bazelbuild/bazel-gazelle/cmd/gazelle
+
+go install ./vendor/github.com/kubernetes/repo-infra/kazel
 
 touch "${KUBE_ROOT}/vendor/BUILD"
 

hack/verify-bazel.sh

@@ -40,9 +40,9 @@ mkdir -p "${_tmp_kuberoot}/.."
 cp -a "${KUBE_ROOT}" "${_tmp_kuberoot}/.."
 
 cd "${_tmp_kuberoot}"
-GOPATH="${_tmp_gopath}" ./hack/update-bazel.sh
+GOPATH="${_tmp_gopath}" PATH="${_tmp_gopath}/bin:${PATH}" ./hack/update-bazel.sh
 
-diff=$(diff -Naupr "${KUBE_ROOT}" "${_tmp_kuberoot}" || true)
+diff=$(diff -Naupr -x '_output' "${KUBE_ROOT}" "${_tmp_kuberoot}" || true)
 
 if [[ -n "${diff}" ]]; then
   echo "${diff}" >&2

hack/verify-godeps.sh

@@ -64,6 +64,7 @@ _kubetmp="${_kubetmp}/kubernetes"
 
 # Do all our work in the new GOPATH
 export GOPATH="${_tmpdir}"
+export PATH="${GOPATH}/bin:${PATH}"
 
 pushd "${_kubetmp}" > /dev/null 2>&1
   # Restore the Godeps into our temp directory

hack/verify-spelling.sh

@@ -20,15 +20,12 @@ set -o pipefail
 export KUBE_ROOT=$(dirname "${BASH_SOURCE}")/..
 source "${KUBE_ROOT}/hack/lib/init.sh"
 
+# Ensure that we find the binaries we build before anything else.
+export GOBIN="${KUBE_OUTPUT_BINPATH}"
+PATH="${GOBIN}:${PATH}"
+
 # Install tools we need, but only from vendor/...
-cd ${KUBE_ROOT}
 go install ./vendor/github.com/client9/misspell/cmd/misspell
-if ! which misspell >/dev/null 2>&1; then
-    echo "Can't find misspell - is your GOPATH 'bin' in your PATH?" >&2
-    echo "  GOPATH: ${GOPATH}" >&2
-    echo "  PATH:   ${PATH}" >&2
-    exit 1
-fi
 
 # Spell checking
 # All the skipping files are defined in hack/.spelling_failures

pkg/generated/openapi/BUILD

@@ -17,6 +17,7 @@ openapi_library(
         "pkg/kubelet/apis/kubeletconfig/v1beta1",
         "pkg/proxy/apis/kubeproxyconfig/v1alpha1",
         "pkg/version",
+        "vendor/github.com/kubernetes/repo-infra/kazel",
     ],
     tags = ["automanaged"],
     vendor_prefix = openapi_vendor_prefix,

vendor/BUILD

@@ -43,6 +43,19 @@ filegroup(
         "//vendor/github.com/aws/aws-sdk-go/service/elbv2:all-srcs",
         "//vendor/github.com/aws/aws-sdk-go/service/kms:all-srcs",
         "//vendor/github.com/aws/aws-sdk-go/service/sts:all-srcs",
+        "//vendor/github.com/bazelbuild/bazel-gazelle/cmd/gazelle:all-srcs",
+        "//vendor/github.com/bazelbuild/bazel-gazelle/internal/config:all-srcs",
+        "//vendor/github.com/bazelbuild/bazel-gazelle/internal/label:all-srcs",
+        "//vendor/github.com/bazelbuild/bazel-gazelle/internal/merger:all-srcs",
+        "//vendor/github.com/bazelbuild/bazel-gazelle/internal/packages:all-srcs",
+        "//vendor/github.com/bazelbuild/bazel-gazelle/internal/pathtools:all-srcs",
+        "//vendor/github.com/bazelbuild/bazel-gazelle/internal/repos:all-srcs",
+        "//vendor/github.com/bazelbuild/bazel-gazelle/internal/resolve:all-srcs",
+        "//vendor/github.com/bazelbuild/bazel-gazelle/internal/rules:all-srcs",
+        "//vendor/github.com/bazelbuild/bazel-gazelle/internal/version:all-srcs",
+        "//vendor/github.com/bazelbuild/bazel-gazelle/internal/wspace:all-srcs",
+        "//vendor/github.com/bazelbuild/buildtools/build:all-srcs",
+        "//vendor/github.com/bazelbuild/buildtools/tables:all-srcs",
         "//vendor/github.com/beorn7/perks/quantile:all-srcs",
         "//vendor/github.com/blang/semver:all-srcs",
         "//vendor/github.com/chai2010/gettext-go/gettext:all-srcs",
@@ -273,6 +286,7 @@ filegroup(
         "//vendor/github.com/kr/pretty:all-srcs",
         "//vendor/github.com/kr/pty:all-srcs",
         "//vendor/github.com/kr/text:all-srcs",
+        "//vendor/github.com/kubernetes/repo-infra/kazel:all-srcs",
         "//vendor/github.com/libopenstorage/openstorage/api:all-srcs",
         "//vendor/github.com/libopenstorage/openstorage/pkg/parser:all-srcs",
         "//vendor/github.com/libopenstorage/openstorage/pkg/units:all-srcs",
@@ -302,7 +316,6 @@ filegroup(
         "//vendor/github.com/opencontainers/runtime-spec/specs-go:all-srcs",
         "//vendor/github.com/opencontainers/selinux/go-selinux:all-srcs",
         "//vendor/github.com/pborman/uuid:all-srcs",
-        "//vendor/github.com/pelletier/go-buffruneio:all-srcs",
         "//vendor/github.com/pelletier/go-toml:all-srcs",
         "//vendor/github.com/peterbourgon/diskv:all-srcs",
         "//vendor/github.com/pkg/errors:all-srcs",

vendor/github.com/bazelbuild/bazel-gazelle/AUTHORS

@@ -0,0 +1,18 @@
+# This is the official list of authors for copyright purposes.
+# Names should be added to this file as:
+# Name or Organization <email address>
+# The email address is not required for organizations.
+
+Andy Hochhaus <hochhaus@users.noreply.github.com>
+Antoine Pelisse <apelisse@gmail.com>
+GinFungYJF <645116215@qq.com>
+Google Inc.
+Improbable Worlds Ltd
+Jeff Hodges <jeff@somethingsimilar.com>
+John Millikin <jmillikin@gmail.com>
+Melinda Lu <melinda@vsco.co>
+Peter McAlpine <peter@aoeu.ca>
+RS <sayrer@gmail.com>
+Rodrigo Queiro <overdrigzed@gmail.com>
+Tom Payne <twpayne@gmail.com>
+Yuki Yugui Sonoda <yugui@yugui.jp>

vendor/github.com/bazelbuild/bazel-gazelle/CONTRIBUTORS

@@ -0,0 +1,29 @@
+# People who have agreed to one of the CLAs and can contribute patches.
+# The AUTHORS file lists the copyright holders; this file
+# lists people.  For example, Google employees are listed here
+# but not in AUTHORS, because Google holds the copyright.
+#
+# https://developers.google.com/open-source/cla/individual
+# https://developers.google.com/open-source/cla/corporate
+#
+# Names should be added to this file as:
+#     Name <email address>
+
+Ainsley Escorce-Jones <ains@users.noreply.github.com>
+Andy Hochhaus <hochhaus@users.noreply.github.com>
+Antoine Pelisse <apelisse@gmail.com>
+GinFungYJF <645116215@qq.com>
+Ian Cottrell <ian.the.hat@gmail.com>
+Jay Conrod <jayconrod@gmail.com>
+Jeff Grafton <ixdy@users.noreply.github.com>
+Jeff Hodges <jeff@somethingsimilar.com>
+John Millikin <jmillikin@gmail.com>
+Kristina <k.chodorow@gmail.com>
+Melinda Lu <melinda@vsco.co>
+Paul Bethe <pbethe@google.com>
+Peter McAlpine <peter@aoeu.ca>
+Rodrigo Queiro <overdrigzed@gmail.com>
+RS <sayrer@gmail.com>
+Stefan Sakalik <stefan@improbable.io>
+Tom Payne <twpayne@gmail.com>
+Yuki Yugui Sonoda <yugui@yugui.jp>

vendor/github.com/bazelbuild/bazel-gazelle/LICENSE

@@ -0,0 +1,202 @@
+
+                                 Apache License
+                           Version 2.0, January 2004
+                        http://www.apache.org/licenses/
+
+   TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION
+
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+
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+      and distribution as defined by Sections 1 through 9 of this document.
+
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+      outstanding shares, or (iii) beneficial ownership of such entity.
+
+      "You" (or "Your") shall mean an individual or Legal Entity
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+      "Source" form shall mean the preferred form for making modifications,
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+
+   7. Disclaimer of Warranty. Unless required by applicable law or
+      agreed to in writing, Licensor provides the Work (and each
+      Contributor provides its Contributions) on an "AS IS" BASIS,
+      WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
+      implied, including, without limitation, any warranties or conditions
+      of TITLE, NON-INFRINGEMENT, MERCHANTABILITY, or FITNESS FOR A
+      PARTICULAR PURPOSE. You are solely responsible for determining the
+      appropriateness of using or redistributing the Work and assume any
+      risks associated with Your exercise of permissions under this License.
+
+   8. Limitation of Liability. In no event and under no legal theory,
+      whether in tort (including negligence), contract, or otherwise,
+      unless required by applicable law (such as deliberate and grossly
+      negligent acts) or agreed to in writing, shall any Contributor be
+      liable to You for damages, including any direct, indirect, special,
+      incidental, or consequential damages of any character arising as a
+      result of this License or out of the use or inability to use the
+      Work (including but not limited to damages for loss of goodwill,
+      work stoppage, computer failure or malfunction, or any and all
+      other commercial damages or losses), even if such Contributor
+      has been advised of the possibility of such damages.
+
+   9. Accepting Warranty or Additional Liability. While redistributing
+      the Work or Derivative Works thereof, You may choose to offer,
+      and charge a fee for, acceptance of support, warranty, indemnity,
+      or other liability obligations and/or rights consistent with this
+      License. However, in accepting such obligations, You may act only
+      on Your own behalf and on Your sole responsibility, not on behalf
+      of any other Contributor, and only if You agree to indemnify,
+      defend, and hold each Contributor harmless for any liability
+      incurred by, or claims asserted against, such Contributor by reason
+      of your accepting any such warranty or additional liability.
+
+   END OF TERMS AND CONDITIONS
+
+   APPENDIX: How to apply the Apache License to your work.
+
+      To apply the Apache License to your work, attach the following
+      boilerplate notice, with the fields enclosed by brackets "[]"
+      replaced with your own identifying information. (Don't include
+      the brackets!)  The text should be enclosed in the appropriate
+      comment syntax for the file format. We also recommend that a
+      file or class name and description of purpose be included on the
+      same "printed page" as the copyright notice for easier
+      identification within third-party archives.
+
+   Copyright [yyyy] [name of copyright owner]
+
+   Licensed under the Apache License, Version 2.0 (the "License");
+   you may not use this file except in compliance with the License.
+   You may obtain a copy of the License at
+
+       http://www.apache.org/licenses/LICENSE-2.0
+
+   Unless required by applicable law or agreed to in writing, software
+   distributed under the License is distributed on an "AS IS" BASIS,
+   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+   See the License for the specific language governing permissions and
+   limitations under the License.

vendor/github.com/bazelbuild/bazel-gazelle/cmd/gazelle/BUILD

@@ -0,0 +1,49 @@
+load("@io_bazel_rules_go//go:def.bzl", "go_binary", "go_library")
+
+go_library(
+    name = "go_default_library",
+    srcs = [
+        "diff.go",
+        "fix.go",
+        "fix-update.go",
+        "flags.go",
+        "gazelle.go",
+        "print.go",
+        "update-repos.go",
+        "version.go",
+    ],
+    importpath = "github.com/bazelbuild/bazel-gazelle/cmd/gazelle",
+    visibility = ["//visibility:private"],
+    deps = [
+        "//vendor/github.com/bazelbuild/bazel-gazelle/internal/config:go_default_library",
+        "//vendor/github.com/bazelbuild/bazel-gazelle/internal/label:go_default_library",
+        "//vendor/github.com/bazelbuild/bazel-gazelle/internal/merger:go_default_library",
+        "//vendor/github.com/bazelbuild/bazel-gazelle/internal/packages:go_default_library",
+        "//vendor/github.com/bazelbuild/bazel-gazelle/internal/repos:go_default_library",
+        "//vendor/github.com/bazelbuild/bazel-gazelle/internal/resolve:go_default_library",
+        "//vendor/github.com/bazelbuild/bazel-gazelle/internal/rules:go_default_library",
+        "//vendor/github.com/bazelbuild/bazel-gazelle/internal/version:go_default_library",
+        "//vendor/github.com/bazelbuild/bazel-gazelle/internal/wspace:go_default_library",
+        "//vendor/github.com/bazelbuild/buildtools/build:go_default_library",
+    ],
+)
+
+go_binary(
+    name = "gazelle",
+    embed = [":go_default_library"],
+    visibility = ["//visibility:public"],
+)
+
+filegroup(
+    name = "package-srcs",
+    srcs = glob(["**"]),
+    tags = ["automanaged"],
+    visibility = ["//visibility:private"],
+)
+
+filegroup(
+    name = "all-srcs",
+    srcs = [":package-srcs"],
+    tags = ["automanaged"],
+    visibility = ["//visibility:public"],
+)

vendor/github.com/bazelbuild/bazel-gazelle/cmd/gazelle/diff.go

@@ -0,0 +1,55 @@
+/* Copyright 2016 The Bazel Authors. All rights reserved.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+   http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package main
+
+import (
+	"bytes"
+	"io/ioutil"
+	"os"
+	"os/exec"
+
+	"github.com/bazelbuild/bazel-gazelle/internal/config"
+	bf "github.com/bazelbuild/buildtools/build"
+)
+
+func diffFile(c *config.Config, file *bf.File, path string) error {
+	oldContents, err := ioutil.ReadFile(file.Path)
+	if err != nil {
+		oldContents = nil
+	}
+	newContents := bf.Format(file)
+	if bytes.Equal(oldContents, newContents) {
+		return nil
+	}
+	f, err := ioutil.TempFile("", c.DefaultBuildFileName())
+	if err != nil {
+		return err
+	}
+	f.Close()
+	defer os.Remove(f.Name())
+	if err := ioutil.WriteFile(f.Name(), newContents, 0666); err != nil {
+		return err
+	}
+	cmd := exec.Command("diff", "-u", "--new-file", path, f.Name())
+	cmd.Stdout = os.Stdout
+	cmd.Stderr = os.Stderr
+	err = cmd.Run()
+	if _, ok := err.(*exec.ExitError); ok {
+		// diff returns non-zero when files are different. This is not an error.
+		return nil
+	}
+	return err
+}

vendor/github.com/bazelbuild/bazel-gazelle/cmd/gazelle/fix-update.go

@@ -0,0 +1,424 @@
+/* Copyright 2017 The Bazel Authors. All rights reserved.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+   http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package main
+
+import (
+	"errors"
+	"flag"
+	"fmt"
+	"io/ioutil"
+	"log"
+	"os"
+	"path/filepath"
+	"strings"
+
+	"github.com/bazelbuild/bazel-gazelle/internal/config"
+	"github.com/bazelbuild/bazel-gazelle/internal/label"
+	"github.com/bazelbuild/bazel-gazelle/internal/merger"
+	"github.com/bazelbuild/bazel-gazelle/internal/packages"
+	"github.com/bazelbuild/bazel-gazelle/internal/repos"
+	"github.com/bazelbuild/bazel-gazelle/internal/resolve"
+	"github.com/bazelbuild/bazel-gazelle/internal/rules"
+	"github.com/bazelbuild/bazel-gazelle/internal/wspace"
+	bf "github.com/bazelbuild/buildtools/build"
+)
+
+// updateConfig holds configuration information needed to run the fix and
+// update commands. This includes everything in config.Config, but it also
+// includes some additional fields that aren't relevant to other packages.
+type updateConfig struct {
+	c                 *config.Config
+	emit              emitFunc
+	outDir, outSuffix string
+	repos             []repos.Repo
+}
+
+type emitFunc func(*config.Config, *bf.File, string) error
+
+var modeFromName = map[string]emitFunc{
+	"print": printFile,
+	"fix":   fixFile,
+	"diff":  diffFile,
+}
+
+// visitRecord stores information about about a directory visited with
+// packages.Walk.
+type visitRecord struct {
+	// pkgRel is the slash-separated path to the visited directory, relative to
+	// the repository root. "" for the repository root itself.
+	pkgRel string
+
+	// rules is a list of generated Go rules.
+	rules []bf.Expr
+
+	// empty is a list of empty Go rules that may be deleted.
+	empty []bf.Expr
+
+	// file is the build file being processed.
+	file *bf.File
+}
+
+type byPkgRel []visitRecord
+
+func (vs byPkgRel) Len() int           { return len(vs) }
+func (vs byPkgRel) Less(i, j int) bool { return vs[i].pkgRel < vs[j].pkgRel }
+func (vs byPkgRel) Swap(i, j int)      { vs[i], vs[j] = vs[j], vs[i] }
+
+func runFixUpdate(cmd command, args []string) error {
+	uc, err := newFixUpdateConfiguration(cmd, args)
+	if err != nil {
+		return err
+	}
+	if cmd == fixCmd {
+		// Only check the version when "fix" is run. Generated build files
+		// frequently work with older version of rules_go, and we don't want to
+		// nag too much since there's no way to disable this warning.
+		checkRulesGoVersion(uc.c.RepoRoot)
+	}
+
+	l := label.NewLabeler(uc.c)
+	ruleIndex := resolve.NewRuleIndex()
+
+	var visits []visitRecord
+
+	// Visit all directories in the repository.
+	packages.Walk(uc.c, uc.c.RepoRoot, func(dir, rel string, c *config.Config, pkg *packages.Package, file *bf.File, isUpdateDir bool) {
+		// If this file is ignored or if Gazelle was not asked to update this
+		// directory, just index the build file and move on.
+		if !isUpdateDir {
+			if file != nil {
+				ruleIndex.AddRulesFromFile(c, file)
+			}
+			return
+		}
+
+		// Fix any problems in the file.
+		if file != nil {
+			file = merger.FixFileMinor(c, file)
+			fixedFile := merger.FixFile(c, file)
+			if cmd == fixCmd {
+				file = fixedFile
+			} else if fixedFile != file {
+				log.Printf("%s: warning: file contains rules whose structure is out of date. Consider running 'gazelle fix'.", file.Path)
+			}
+		}
+
+		// If the file exists, but no Go code is present, create an empty package.
+		// This lets us delete existing rules.
+		if pkg == nil && file != nil {
+			pkg = packages.EmptyPackage(c, dir, rel)
+		}
+
+		// Generate new rules and merge them into the existing file (if present).
+		if pkg != nil {
+			g := rules.NewGenerator(c, l, file)
+			rules, empty, err := g.GenerateRules(pkg)
+			if err != nil {
+				log.Print(err)
+				return
+			}
+			if file == nil {
+				file = &bf.File{
+					Path: filepath.Join(c.RepoRoot, filepath.FromSlash(rel), c.DefaultBuildFileName()),
+					Stmt: rules,
+				}
+			} else {
+				file, rules = merger.MergeFile(rules, empty, file, merger.PreResolveAttrs)
+			}
+			visits = append(visits, visitRecord{
+				pkgRel: rel,
+				rules:  rules,
+				empty:  empty,
+				file:   file,
+			})
+		}
+
+		// Add library rules to the dependency resolution table.
+		if file != nil {
+			ruleIndex.AddRulesFromFile(c, file)
+		}
+	})
+
+	// Finish building the index for dependency resolution.
+	ruleIndex.Finish()
+
+	// Resolve dependencies.
+	rc := repos.NewRemoteCache(uc.repos)
+	resolver := resolve.NewResolver(uc.c, l, ruleIndex, rc)
+	for i := range visits {
+		for j := range visits[i].rules {
+			visits[i].rules[j] = resolver.ResolveRule(visits[i].rules[j], visits[i].pkgRel)
+		}
+		visits[i].file, _ = merger.MergeFile(visits[i].rules, visits[i].empty, visits[i].file, merger.PostResolveAttrs)
+	}
+
+	// Emit merged files.
+	for _, v := range visits {
+		rules.SortLabels(v.file)
+		v.file = merger.FixLoads(v.file)
+		bf.Rewrite(v.file, nil) // have buildifier 'format' our rules.
+
+		path := v.file.Path
+		if uc.outDir != "" {
+			stem := filepath.Base(v.file.Path) + uc.outSuffix
+			path = filepath.Join(uc.outDir, v.pkgRel, stem)
+		}
+		if err := uc.emit(uc.c, v.file, path); err != nil {
+			log.Print(err)
+		}
+	}
+	return nil
+}
+
+func newFixUpdateConfiguration(cmd command, args []string) (*updateConfig, error) {
+	uc := &updateConfig{c: &config.Config{}}
+	var err error
+
+	fs := flag.NewFlagSet("gazelle", flag.ContinueOnError)
+	// Flag will call this on any parse error. Don't print usage unless
+	// -h or -help were passed explicitly.
+	fs.Usage = func() {}
+
+	knownImports := multiFlag{}
+	buildFileName := fs.String("build_file_name", "BUILD.bazel,BUILD", "comma-separated list of valid build file names.\nThe first element of the list is the name of output build files to generate.")
+	buildTags := fs.String("build_tags", "", "comma-separated list of build tags. If not specified, Gazelle will not\n\tfilter sources with build constraints.")
+	external := fs.String("external", "external", "external: resolve external packages with go_repository\n\tvendored: resolve external packages as packages in vendor/")
+	var goPrefix explicitFlag
+	fs.Var(&goPrefix, "go_prefix", "prefix of import paths in the current workspace")
+	repoRoot := fs.String("repo_root", "", "path to a directory which corresponds to go_prefix, otherwise gazelle searches for it.")
+	fs.Var(&knownImports, "known_import", "import path for which external resolution is skipped (can specify multiple times)")
+	mode := fs.String("mode", "fix", "print: prints all of the updated BUILD files\n\tfix: rewrites all of the BUILD files in place\n\tdiff: computes the rewrite but then just does a diff")
+	outDir := fs.String("experimental_out_dir", "", "write build files to an alternate directory tree")
+	outSuffix := fs.String("experimental_out_suffix", "", "extra suffix appended to build file names. Only used if -experimental_out_dir is also set.")
+	var proto explicitFlag
+	fs.Var(&proto, "proto", "default: generates new proto rules\n\tdisable: does not touch proto rules\n\tlegacy (deprecated): generates old proto rules")
+	if err := fs.Parse(args); err != nil {
+		if err == flag.ErrHelp {
+			fixUpdateUsage(fs)
+			os.Exit(0)
+		}
+		// flag already prints the error; don't print it again.
+		log.Fatal("Try -help for more information.")
+	}
+
+	uc.c.Dirs = fs.Args()
+	if len(uc.c.Dirs) == 0 {
+		uc.c.Dirs = []string{"."}
+	}
+	for i := range uc.c.Dirs {
+		uc.c.Dirs[i], err = filepath.Abs(uc.c.Dirs[i])
+		if err != nil {
+			return nil, err
+		}
+	}
+
+	if *repoRoot != "" {
+		uc.c.RepoRoot = *repoRoot
+	} else if len(uc.c.Dirs) == 1 {
+		uc.c.RepoRoot, err = wspace.Find(uc.c.Dirs[0])
+		if err != nil {
+			return nil, fmt.Errorf("-repo_root not specified, and WORKSPACE cannot be found: %v", err)
+		}
+	} else {
+		uc.c.RepoRoot, err = wspace.Find(".")
+		if err != nil {
+			return nil, fmt.Errorf("-repo_root not specified, and WORKSPACE cannot be found: %v", err)
+		}
+	}
+	uc.c.RepoRoot, err = filepath.EvalSymlinks(uc.c.RepoRoot)
+	if err != nil {
+		return nil, fmt.Errorf("failed to evaluate symlinks for repo root: %v", err)
+	}
+
+	for _, dir := range uc.c.Dirs {
+		if !isDescendingDir(dir, uc.c.RepoRoot) {
+			return nil, fmt.Errorf("dir %q is not a subdirectory of repo root %q", dir, uc.c.RepoRoot)
+		}
+	}
+
+	uc.c.ValidBuildFileNames = strings.Split(*buildFileName, ",")
+	if len(uc.c.ValidBuildFileNames) == 0 {
+		return nil, fmt.Errorf("no valid build file names specified")
+	}
+
+	uc.c.SetBuildTags(*buildTags)
+	uc.c.PreprocessTags()
+
+	if goPrefix.set {
+		uc.c.GoPrefix = goPrefix.value
+	} else {
+		uc.c.GoPrefix, err = loadGoPrefix(uc.c)
+		if err != nil {
+			return nil, err
+		}
+	}
+	if err := config.CheckPrefix(uc.c.GoPrefix); err != nil {
+		return nil, err
+	}
+
+	uc.c.ShouldFix = cmd == fixCmd
+
+	uc.c.DepMode, err = config.DependencyModeFromString(*external)
+	if err != nil {
+		return nil, err
+	}
+
+	if proto.set {
+		uc.c.ProtoMode, err = config.ProtoModeFromString(proto.value)
+		if err != nil {
+			return nil, err
+		}
+		uc.c.ProtoModeExplicit = true
+	}
+
+	emit, ok := modeFromName[*mode]
+	if !ok {
+		return nil, fmt.Errorf("unrecognized emit mode: %q", *mode)
+	}
+	uc.emit = emit
+
+	uc.outDir = *outDir
+	uc.outSuffix = *outSuffix
+
+	workspacePath := filepath.Join(uc.c.RepoRoot, "WORKSPACE")
+	workspaceContent, err := ioutil.ReadFile(workspacePath)
+	if os.IsNotExist(err) {
+		workspaceContent = nil
+	} else if err != nil {
+		return nil, err
+	}
+	workspace, err := bf.Parse(workspacePath, workspaceContent)
+	if err != nil {
+		return nil, err
+	}
+	uc.repos = repos.ListRepositories(workspace)
+	repoPrefixes := make(map[string]bool)
+	for _, r := range uc.repos {
+		repoPrefixes[r.GoPrefix] = true
+	}
+	for _, imp := range knownImports {
+		if repoPrefixes[imp] {
+			continue
+		}
+		repo := repos.Repo{
+			Name:     label.ImportPathToBazelRepoName(imp),
+			GoPrefix: imp,
+		}
+		uc.repos = append(uc.repos, repo)
+	}
+
+	return uc, nil
+}
+
+func fixUpdateUsage(fs *flag.FlagSet) {
+	fmt.Fprintln(os.Stderr, `usage: gazelle [fix|update] [flags...] [package-dirs...]
+
+The update command creates new build files and update existing BUILD files
+when needed.
+
+The fix command also creates and updates build files, and in addition, it may
+make potentially breaking updates to usage of rules. For example, it may
+delete obsolete rules or rename existing rules.
+
+There are several output modes which can be selected with the -mode flag. The
+output mode determines what Gazelle does with updated BUILD files.
+
+  fix (default) - write updated BUILD files back to disk.
+  print - print updated BUILD files to stdout.
+  diff - diff updated BUILD files against existing files in unified format.
+
+Gazelle accepts a list of paths to Go package directories to process (defaults
+to the working directory if none are given). It recursively traverses
+subdirectories. All directories must be under the directory specified by
+-repo_root; if -repo_root is not given, this is the directory containing the
+WORKSPACE file.
+
+FLAGS:
+`)
+	fs.PrintDefaults()
+}
+
+func loadBuildFile(c *config.Config, dir string) (*bf.File, error) {
+	var buildPath string
+	for _, base := range c.ValidBuildFileNames {
+		p := filepath.Join(dir, base)
+		fi, err := os.Stat(p)
+		if err == nil {
+			if fi.Mode().IsRegular() {
+				buildPath = p
+				break
+			}
+			continue
+		}
+		if !os.IsNotExist(err) {
+			return nil, err
+		}
+	}
+	if buildPath == "" {
+		return nil, os.ErrNotExist
+	}
+
+	data, err := ioutil.ReadFile(buildPath)
+	if err != nil {
+		return nil, err
+	}
+	return bf.Parse(buildPath, data)
+}
+
+func loadGoPrefix(c *config.Config) (string, error) {
+	f, err := loadBuildFile(c, c.RepoRoot)
+	if err != nil {
+		return "", errors.New("-go_prefix not set")
+	}
+	for _, d := range config.ParseDirectives(f) {
+		if d.Key == "prefix" {
+			return d.Value, nil
+		}
+	}
+	for _, s := range f.Stmt {
+		c, ok := s.(*bf.CallExpr)
+		if !ok {
+			continue
+		}
+		l, ok := c.X.(*bf.LiteralExpr)
+		if !ok {
+			continue
+		}
+		if l.Token != "go_prefix" {
+			continue
+		}
+		if len(c.List) != 1 {
+			return "", fmt.Errorf("-go_prefix not set, and %s has go_prefix(%v) with too many args", f.Path, c.List)
+		}
+		v, ok := c.List[0].(*bf.StringExpr)
+		if !ok {
+			return "", fmt.Errorf("-go_prefix not set, and %s has go_prefix(%v) which is not a string", f.Path, bf.FormatString(c.List[0]))
+		}
+		return v.Value, nil
+	}
+	return "", fmt.Errorf("-go_prefix not set, and no # gazelle:prefix directive found in %s", f.Path)
+}
+
+func isDescendingDir(dir, root string) bool {
+	rel, err := filepath.Rel(root, dir)
+	if err != nil {
+		return false
+	}
+	if rel == "." {
+		return true
+	}
+	return !strings.HasPrefix(rel, "..")
+}

vendor/github.com/bazelbuild/bazel-gazelle/cmd/gazelle/fix.go

@@ -0,0 +1,35 @@
+/* Copyright 2016 The Bazel Authors. All rights reserved.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+   http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package main
+
+import (
+	"io/ioutil"
+	"os"
+	"path/filepath"
+
+	"github.com/bazelbuild/bazel-gazelle/internal/config"
+	bf "github.com/bazelbuild/buildtools/build"
+)
+
+func fixFile(c *config.Config, file *bf.File, path string) error {
+	if err := os.MkdirAll(filepath.Dir(path), 0777); err != nil {
+		return err
+	}
+	if err := ioutil.WriteFile(path, bf.Format(file), 0666); err != nil {
+		return err
+	}
+	return nil
+}

vendor/github.com/bazelbuild/bazel-gazelle/cmd/gazelle/flags.go

@@ -0,0 +1,51 @@
+// Copyright 2017 The Bazel Authors. All rights reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//    http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package main
+
+import "fmt"
+
+// multiFlag allows repeated string flags to be collected into a slice
+type multiFlag []string
+
+func (m *multiFlag) String() string {
+	if len(*m) == 0 {
+		return ""
+	}
+	return fmt.Sprint(*m)
+}
+
+func (m *multiFlag) Set(v string) error {
+	(*m) = append(*m, v)
+	return nil
+}
+
+// explicitFlag is a string flag that tracks whether it was set.
+type explicitFlag struct {
+	set   bool
+	value string
+}
+
+func (f *explicitFlag) Set(value string) error {
+	f.set = true
+	f.value = value
+	return nil
+}
+
+func (f *explicitFlag) String() string {
+	if f == nil {
+		return ""
+	}
+	return f.value
+}

vendor/github.com/bazelbuild/bazel-gazelle/cmd/gazelle/gazelle.go

@@ -0,0 +1,106 @@
+/* Copyright 2016 The Bazel Authors. All rights reserved.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+   http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+// Command gazelle is a BUILD file generator for Go projects.
+// See "gazelle --help" for more details.
+package main
+
+import (
+	"fmt"
+	"log"
+	"os"
+)
+
+type command int
+
+const (
+	updateCmd command = iota
+	fixCmd
+	updateReposCmd
+	helpCmd
+)
+
+var commandFromName = map[string]command{
+	"fix":          fixCmd,
+	"help":         helpCmd,
+	"update":       updateCmd,
+	"update-repos": updateReposCmd,
+}
+
+func main() {
+	log.SetPrefix("gazelle: ")
+	log.SetFlags(0) // don't print timestamps
+
+	if err := run(os.Args[1:]); err != nil {
+		log.Fatal(err)
+	}
+}
+
+func run(args []string) error {
+	cmd := updateCmd
+	if len(args) == 1 && (args[0] == "-h" || args[0] == "-help" || args[0] == "--help") {
+		cmd = helpCmd
+	} else if len(args) > 0 {
+		c, ok := commandFromName[args[0]]
+		if ok {
+			cmd = c
+			args = args[1:]
+		}
+	}
+
+	switch cmd {
+	case fixCmd, updateCmd:
+		return runFixUpdate(cmd, args)
+	case helpCmd:
+		help()
+	case updateReposCmd:
+		return updateRepos(args)
+	default:
+		log.Panicf("unknown command: %v", cmd)
+	}
+	return nil
+}
+
+func help() {
+	fmt.Fprint(os.Stderr, `usage: gazelle <command> [args...]
+
+Gazelle is a BUILD file generator for Go projects. It can create new BUILD files
+for a project that follows "go build" conventions, and it can update BUILD files
+if they already exist. It can be invoked directly in a project workspace, or
+it can be run on an external dependency during the build as part of the
+go_repository rule.
+
+Gazelle may be run with one of the commands below. If no command is given,
+Gazelle defaults to "update".
+
+  update - Gazelle will create new BUILD files or update existing BUILD files
+      if needed.
+  fix - in addition to the changes made in update, Gazelle will make potentially
+      breaking changes. For example, it may delete obsolete rules or rename
+      existing rules.
+  update-repos - updates repository rules in the WORKSPACE file. Run with
+      -h for details.
+  help - show this message.
+
+For usage information for a specific command, run the command with the -h flag.
+For example:
+
+  gazelle update -h
+
+Gazelle is under active delevopment, and its interface may change
+without notice.
+
+`)
+}

vendor/github.com/bazelbuild/bazel-gazelle/cmd/gazelle/print.go

@@ -0,0 +1,28 @@
+/* Copyright 2016 The Bazel Authors. All rights reserved.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+   http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package main
+
+import (
+	"os"
+
+	"github.com/bazelbuild/bazel-gazelle/internal/config"
+	bf "github.com/bazelbuild/buildtools/build"
+)
+
+func printFile(c *config.Config, f *bf.File, _ string) error {
+	_, err := os.Stdout.Write(bf.Format(f))
+	return err
+}

vendor/github.com/bazelbuild/bazel-gazelle/cmd/gazelle/update-repos.go

@@ -0,0 +1,176 @@
+/* Copyright 2017 The Bazel Authors. All rights reserved.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+   http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package main
+
+import (
+	"errors"
+	"flag"
+	"fmt"
+	"io/ioutil"
+	"os"
+	"path/filepath"
+	"sync"
+
+	"github.com/bazelbuild/bazel-gazelle/internal/merger"
+	"github.com/bazelbuild/bazel-gazelle/internal/repos"
+	"github.com/bazelbuild/bazel-gazelle/internal/wspace"
+	bf "github.com/bazelbuild/buildtools/build"
+)
+
+type updateReposFn func(c *updateReposConfiguration, oldFile *bf.File) (*bf.File, error)
+
+type updateReposConfiguration struct {
+	fn           updateReposFn
+	repoRoot     string
+	lockFilename string
+	importPaths  []string
+}
+
+func updateRepos(args []string) error {
+	c, err := newUpdateReposConfiguration(args)
+	if err != nil {
+		return err
+	}
+
+	workspacePath := filepath.Join(c.repoRoot, "WORKSPACE")
+	content, err := ioutil.ReadFile(workspacePath)
+	if err != nil {
+		return fmt.Errorf("error reading %q: %v", workspacePath, err)
+	}
+	oldFile, err := bf.Parse(workspacePath, content)
+	if err != nil {
+		return fmt.Errorf("error parsing %q: %v", workspacePath, err)
+	}
+
+	mergedFile, err := c.fn(c, oldFile)
+	if err != nil {
+		return err
+	}
+	mergedFile = merger.FixLoads(mergedFile)
+	if err := ioutil.WriteFile(mergedFile.Path, bf.Format(mergedFile), 0666); err != nil {
+		return fmt.Errorf("error writing %q: %v", mergedFile.Path, err)
+	}
+	return nil
+}
+
+func newUpdateReposConfiguration(args []string) (*updateReposConfiguration, error) {
+	c := new(updateReposConfiguration)
+	fs := flag.NewFlagSet("gazelle", flag.ContinueOnError)
+	// Flag will call this on any parse error. Don't print usage unless
+	// -h or -help were passed explicitly.
+	fs.Usage = func() {}
+
+	fromFileFlag := fs.String("from_file", "", "Gazelle will translate repositories listed in this file into repository rules in WORKSPACE. Currently only dep's Gopkg.lock is supported.")
+	repoRootFlag := fs.String("repo_root", "", "path to the root directory of the repository. If unspecified, this is assumed to be the directory containing WORKSPACE.")
+	if err := fs.Parse(args); err != nil {
+		if err == flag.ErrHelp {
+			updateReposUsage(fs)
+			os.Exit(0)
+		}
+		// flag already prints the error; don't print it again.
+		return nil, errors.New("Try -help for more information")
+	}
+
+	// Handle general flags that apply to all subcommands.
+	c.repoRoot = *repoRootFlag
+	if c.repoRoot == "" {
+		if repoRoot, err := wspace.Find("."); err != nil {
+			return nil, err
+		} else {
+			c.repoRoot = repoRoot
+		}
+	}
+
+	// Handle flags specific to each subcommand.
+	switch {
+	case *fromFileFlag != "":
+		if len(fs.Args()) != 0 {
+			return nil, fmt.Errorf("Got %d positional arguments with -from_file; wanted 0.\nTry -help for more information.", len(fs.Args()))
+		}
+		c.fn = importFromLockFile
+		c.lockFilename = *fromFileFlag
+
+	default:
+		if len(fs.Args()) == 0 {
+			return nil, fmt.Errorf("No repositories specified\nTry -help for more information.")
+		}
+		c.fn = updateImportPaths
+		c.importPaths = fs.Args()
+	}
+
+	return c, nil
+}
+
+func updateReposUsage(fs *flag.FlagSet) {
+	fmt.Fprintln(os.Stderr, `usage:
+
+# Add/update repositories by import path
+gazelle update-repos example.com/repo1 example.com/repo2
+
+# Import repositories from lock file
+gazelle update-repos -from_file=file
+
+The update-repos command updates repository rules in the WORKSPACE file.
+update-repos can add or update repositories explicitly by import path.
+update-repos can also import repository rules from a vendoring tool's lock
+file (currently only deps' Gopkg.lock is supported).
+
+FLAGS:
+`)
+}
+
+func updateImportPaths(c *updateReposConfiguration, oldFile *bf.File) (*bf.File, error) {
+	rs := repos.ListRepositories(oldFile)
+	rc := repos.NewRemoteCache(rs)
+
+	genRules := make([]bf.Expr, len(c.importPaths))
+	errs := make([]error, len(c.importPaths))
+	var wg sync.WaitGroup
+	wg.Add(len(c.importPaths))
+	for i, imp := range c.importPaths {
+		go func(i int) {
+			defer wg.Done()
+			repo, err := repos.UpdateRepo(rc, imp)
+			if err != nil {
+				errs[i] = err
+				return
+			}
+			repo.Remote = "" // don't set these explicitly
+			repo.VCS = ""
+			rule := repos.GenerateRule(repo)
+			genRules[i] = rule
+		}(i)
+	}
+	wg.Wait()
+
+	for _, err := range errs {
+		if err != nil {
+			return nil, err
+		}
+	}
+	mergedFile, _ := merger.MergeFile(genRules, nil, oldFile, merger.RepoAttrs)
+	return mergedFile, nil
+}
+
+func importFromLockFile(c *updateReposConfiguration, oldFile *bf.File) (*bf.File, error) {
+	genRules, err := repos.ImportRepoRules(c.lockFilename)
+	if err != nil {
+		return nil, err
+	}
+
+	mergedFile, _ := merger.MergeFile(genRules, nil, oldFile, merger.RepoAttrs)
+	return mergedFile, nil
+}

vendor/github.com/bazelbuild/bazel-gazelle/cmd/gazelle/version.go

@@ -0,0 +1,65 @@
+/* Copyright 2018 The Bazel Authors. All rights reserved.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+   http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package main
+
+import (
+	"io/ioutil"
+	"log"
+	"path/filepath"
+	"regexp"
+
+	"github.com/bazelbuild/bazel-gazelle/internal/config"
+	"github.com/bazelbuild/bazel-gazelle/internal/repos"
+	"github.com/bazelbuild/bazel-gazelle/internal/version"
+)
+
+var minimumRulesGoVersion = version.Version{0, 9, 0}
+
+// checkRulesGoVersion checks whether a compatible version of rules_go is
+// being used in the workspace. A message will be logged if an incompatible
+// version is found.
+//
+// Note that we can't always determine the version of rules_go in use. Also,
+// if we find an incompatible version, we shouldn't bail out since the
+// incompatibility may not matter in the current workspace.
+func checkRulesGoVersion(repoRoot string) {
+	const message = `Gazelle may not be compatible with this version of rules_go.
+Update io_bazel_rules_go to a newer version in your WORKSPACE file.`
+
+	rulesGoPath, err := repos.FindExternalRepo(repoRoot, config.RulesGoRepoName)
+	if err != nil {
+		return
+	}
+	defBzlPath := filepath.Join(rulesGoPath, "go", "def.bzl")
+	defBzlContent, err := ioutil.ReadFile(defBzlPath)
+	if err != nil {
+		return
+	}
+	versionRe := regexp.MustCompile(`(?m)^RULES_GO_VERSION = ['"]([0-9.]*)['"]`)
+	match := versionRe.FindSubmatch(defBzlContent)
+	if match == nil {
+		log.Printf("RULES_GO_VERSION not found in @%s//go:def.bzl.\n%s", config.RulesGoRepoName, message)
+		return
+	}
+	vstr := string(match[1])
+	v, err := version.ParseVersion(vstr)
+	if err != nil {
+		log.Printf("RULES_GO_VERSION %q could not be parsed in @%s//go:def.bzl.\n%s", vstr, config.RulesGoRepoName, message)
+	}
+	if v.Compare(minimumRulesGoVersion) < 0 {
+		log.Printf("Found RULES_GO_VERSION %s. Minimum compatible version is %s.\n%s", v, minimumRulesGoVersion, message)
+	}
+}

vendor/github.com/bazelbuild/bazel-gazelle/internal/config/BUILD

@@ -0,0 +1,28 @@
+load("@io_bazel_rules_go//go:def.bzl", "go_library")
+
+go_library(
+    name = "go_default_library",
+    srcs = [
+        "config.go",
+        "constants.go",
+        "directives.go",
+        "platform.go",
+    ],
+    importpath = "github.com/bazelbuild/bazel-gazelle/internal/config",
+    visibility = ["//vendor/github.com/bazelbuild/bazel-gazelle:__subpackages__"],
+    deps = ["//vendor/github.com/bazelbuild/buildtools/build:go_default_library"],
+)
+
+filegroup(
+    name = "package-srcs",
+    srcs = glob(["**"]),
+    tags = ["automanaged"],
+    visibility = ["//visibility:private"],
+)
+
+filegroup(
+    name = "all-srcs",
+    srcs = [":package-srcs"],
+    tags = ["automanaged"],
+    visibility = ["//visibility:public"],
+)

vendor/github.com/bazelbuild/bazel-gazelle/internal/config/config.go

@@ -0,0 +1,175 @@
+/* Copyright 2017 The Bazel Authors. All rights reserved.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+   http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package config
+
+import (
+	"fmt"
+	"go/build"
+	"strings"
+)
+
+// Config holds information about how Gazelle should run. This is mostly
+// based on command-line arguments.
+type Config struct {
+	// Dirs is a list of absolute paths to directories where Gazelle should run.
+	Dirs []string
+
+	// RepoRoot is the absolute, canonical path to the root directory of the
+	// repository with all symlinks resolved.
+	RepoRoot string
+
+	// ValidBuildFileNames is a list of base names that are considered valid
+	// build files. Some repositories may have files named "BUILD" that are not
+	// used by Bazel and should be ignored. Must contain at least one string.
+	ValidBuildFileNames []string
+
+	// GenericTags is a set of build constraints that are true on all platforms.
+	// It should not be nil.
+	GenericTags BuildTags
+
+	// GoPrefix is the portion of the import path for the root of this repository.
+	// This is used to map imports to labels within the repository.
+	GoPrefix string
+
+	// GoPrefixRel is the slash-separated path to the directory where GoPrefix
+	// was set, relative to the repository root. "" for the repository root.
+	GoPrefixRel string
+
+	// ShouldFix determines whether Gazelle attempts to remove and replace
+	// usage of deprecated rules.
+	ShouldFix bool
+
+	// DepMode determines how imports outside of GoPrefix are resolved.
+	DepMode DependencyMode
+
+	// ProtoMode determines how rules are generated for protos.
+	ProtoMode ProtoMode
+
+	// ProtoModeExplicit indicates whether the proto mode was set explicitly.
+	ProtoModeExplicit bool
+}
+
+var DefaultValidBuildFileNames = []string{"BUILD.bazel", "BUILD"}
+
+func (c *Config) IsValidBuildFileName(name string) bool {
+	for _, n := range c.ValidBuildFileNames {
+		if name == n {
+			return true
+		}
+	}
+	return false
+}
+
+func (c *Config) DefaultBuildFileName() string {
+	return c.ValidBuildFileNames[0]
+}
+
+// BuildTags is a set of build constraints.
+type BuildTags map[string]bool
+
+// SetBuildTags sets GenericTags by parsing as a comma separated list. An
+// error will be returned for tags that wouldn't be recognized by "go build".
+// PreprocessTags should be called after this.
+func (c *Config) SetBuildTags(tags string) error {
+	c.GenericTags = make(BuildTags)
+	if tags == "" {
+		return nil
+	}
+	for _, t := range strings.Split(tags, ",") {
+		if strings.HasPrefix(t, "!") {
+			return fmt.Errorf("build tags can't be negated: %s", t)
+		}
+		c.GenericTags[t] = true
+	}
+	return nil
+}
+
+// PreprocessTags adds some tags which are on by default before they are
+// used to match files.
+func (c *Config) PreprocessTags() {
+	if c.GenericTags == nil {
+		c.GenericTags = make(BuildTags)
+	}
+	c.GenericTags["gc"] = true
+}
+
+// CheckPrefix checks that a string may be used as a prefix. We forbid local
+// (relative) imports and those beginning with "/". We allow the empty string,
+// but generated rules must not have an empty importpath.
+func CheckPrefix(prefix string) error {
+	if strings.HasPrefix(prefix, "/") || build.IsLocalImport(prefix) {
+		return fmt.Errorf("invalid prefix: %q", prefix)
+	}
+	return nil
+}
+
+// DependencyMode determines how imports of packages outside of the prefix
+// are resolved.
+type DependencyMode int
+
+const (
+	// ExternalMode indicates imports should be resolved to external dependencies
+	// (declared in WORKSPACE).
+	ExternalMode DependencyMode = iota
+
+	// VendorMode indicates imports should be resolved to libraries in the
+	// vendor directory.
+	VendorMode
+)
+
+// DependencyModeFromString converts a string from the command line
+// to a DependencyMode. Valid strings are "external", "vendor". An error will
+// be returned for an invalid string.
+func DependencyModeFromString(s string) (DependencyMode, error) {
+	switch s {
+	case "external":
+		return ExternalMode, nil
+	case "vendored":
+		return VendorMode, nil
+	default:
+		return 0, fmt.Errorf("unrecognized dependency mode: %q", s)
+	}
+}
+
+// ProtoMode determines how proto rules are generated.
+type ProtoMode int
+
+const (
+	// DefaultProtoMode generates proto_library and new grpc_proto_library rules.
+	// .pb.go files are excluded when there is a .proto file with a similar name.
+	DefaultProtoMode ProtoMode = iota
+
+	// DisableProtoMode ignores .proto files. .pb.go files are treated
+	// as normal sources.
+	DisableProtoMode
+
+	// LegacyProtoMode generates filegroups for .proto files if .pb.go files
+	// are present in the same directory.
+	LegacyProtoMode
+)
+
+func ProtoModeFromString(s string) (ProtoMode, error) {
+	switch s {
+	case "default":
+		return DefaultProtoMode, nil
+	case "disable":
+		return DisableProtoMode, nil
+	case "legacy":
+		return LegacyProtoMode, nil
+	default:
+		return 0, fmt.Errorf("unrecognized proto mode: %q", s)
+	}
+}

vendor/github.com/bazelbuild/bazel-gazelle/internal/config/constants.go

@@ -0,0 +1,78 @@
+/* Copyright 2017 The Bazel Authors. All rights reserved.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+   http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package config
+
+const (
+	// RulesGoRepoName is the canonical name of the rules_go repository. It must
+	// match the workspace name in WORKSPACE.
+	RulesGoRepoName = "io_bazel_rules_go"
+	// DefaultLibName is the name of the default go_library rule in a Go
+	// package directory. It must be consistent to DEFAULT_LIB in go/private/common.bf.
+	DefaultLibName = "go_default_library"
+	// DefaultTestName is a name of an internal test corresponding to
+	// DefaultLibName. It does not need to be consistent to something but it
+	// just needs to be unique in the Bazel package
+	DefaultTestName = "go_default_test"
+	// DefaultXTestName is a name of an external test corresponding to
+	// DefaultLibName.
+	DefaultXTestName = "go_default_xtest"
+	// DefaultProtosName is the name of a filegroup created
+	// whenever the library contains .pb.go files
+	DefaultProtosName = "go_default_library_protos"
+	// DefaultCgoLibName is the name of the default cgo_library rule in a Go package directory.
+	DefaultCgoLibName = "cgo_default_library"
+
+	// GrpcCompilerLabel is the label for the gRPC compiler plugin, used in the
+	// "compilers" attribute of go_proto_library rules.
+	GrpcCompilerLabel = "@io_bazel_rules_go//proto:go_grpc"
+
+	// WellKnownTypesProtoRepo is the repository containing proto_library rules
+	// for the Well Known Types.
+	WellKnownTypesProtoRepo = "com_google_protobuf"
+	// WellKnownTypesGoProtoRepo is the repository containing go_library rules
+	// for the Well Known Types.
+	WellKnownTypesGoProtoRepo = "com_github_golang_protobuf"
+	// WellKnownTypesGoPrefix is the import path for the Go repository containing
+	// pre-generated code for the Well Known Types.
+	WellKnownTypesGoPrefix = "github.com/golang/protobuf"
+
+	// GazelleImportsKey is an internal attribute that lists imported packages
+	// on generated rules. It is replaced with "deps" during import resolution.
+	GazelleImportsKey = "_gazelle_imports"
+)
+
+// Language is the name of a programming langauge that Gazelle knows about.
+// This is used to specify import paths.
+type Language int
+
+const (
+	// GoLang marks Go targets.
+	GoLang Language = iota
+
+	// ProtoLang marks protocol buffer targets.
+	ProtoLang
+)
+
+func (l Language) String() string {
+	switch l {
+	case GoLang:
+		return "go"
+	case ProtoLang:
+		return "proto"
+	default:
+		return "unknown"
+	}
+}

vendor/github.com/bazelbuild/bazel-gazelle/internal/config/directives.go

@@ -0,0 +1,203 @@
+/* Copyright 2017 The Bazel Authors. All rights reserved.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+   http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package config
+
+import (
+	"log"
+	"path"
+	"regexp"
+	"strings"
+
+	bf "github.com/bazelbuild/buildtools/build"
+)
+
+// Directive is a key-value pair extracted from a top-level comment in
+// a build file. Directives have the following format:
+//
+//     # gazelle:key value
+//
+// Keys may not contain spaces. Values may be empty and may contain spaces,
+// but surrounding space is trimmed.
+type Directive struct {
+	Key, Value string
+}
+
+// Top-level directives apply to the whole package or build file. They must
+// appear before the first statement.
+var knownTopLevelDirectives = map[string]bool{
+	"build_file_name": true,
+	"build_tags":      true,
+	"exclude":         true,
+	"prefix":          true,
+	"ignore":          true,
+	"proto":           true,
+}
+
+// TODO(jayconrod): annotation directives will apply to an individual rule.
+// They must appear in the block of comments above that rule.
+
+// ParseDirectives scans f for Gazelle directives. The full list of directives
+// is returned. Errors are reported for unrecognized directives and directives
+// out of place (after the first statement).
+func ParseDirectives(f *bf.File) []Directive {
+	var directives []Directive
+	parseComment := func(com bf.Comment) {
+		match := directiveRe.FindStringSubmatch(com.Token)
+		if match == nil {
+			return
+		}
+		key, value := match[1], match[2]
+		if _, ok := knownTopLevelDirectives[key]; !ok {
+			log.Printf("%s:%d: unknown directive: %s", f.Path, com.Start.Line, com.Token)
+			return
+		}
+		directives = append(directives, Directive{key, value})
+	}
+
+	for _, s := range f.Stmt {
+		coms := s.Comment()
+		for _, com := range coms.Before {
+			parseComment(com)
+		}
+		for _, com := range coms.After {
+			parseComment(com)
+		}
+	}
+	return directives
+}
+
+var directiveRe = regexp.MustCompile(`^#\s*gazelle:(\w+)\s*(.*?)\s*$`)
+
+// ApplyDirectives applies directives that modify the configuration to a copy of
+// c, which is returned. If there are no configuration directives, c is returned
+// unmodified.
+func ApplyDirectives(c *Config, directives []Directive, rel string) *Config {
+	modified := *c
+	didModify := false
+	for _, d := range directives {
+		switch d.Key {
+		case "build_tags":
+			if err := modified.SetBuildTags(d.Value); err != nil {
+				log.Print(err)
+				modified.GenericTags = c.GenericTags
+			} else {
+				modified.PreprocessTags()
+				didModify = true
+			}
+		case "build_file_name":
+			modified.ValidBuildFileNames = strings.Split(d.Value, ",")
+			didModify = true
+		case "prefix":
+			if err := CheckPrefix(d.Value); err != nil {
+				log.Print(err)
+				continue
+			}
+			modified.GoPrefix = d.Value
+			modified.GoPrefixRel = rel
+			didModify = true
+		case "proto":
+			protoMode, err := ProtoModeFromString(d.Value)
+			if err != nil {
+				log.Print(err)
+				continue
+			}
+			modified.ProtoMode = protoMode
+			modified.ProtoModeExplicit = true
+			didModify = true
+		}
+	}
+	if !didModify {
+		return c
+	}
+	return &modified
+}
+
+// InferProtoMode sets Config.ProtoMode, based on the contents of f.  If the
+// proto mode is already set to something other than the default, or if the mode
+// is set explicitly in directives, this function does not change it. If the
+// legacy go_proto_library.bzl is loaded, or if this is the Well Known Types
+// repository, legacy mode is used. If go_proto_library is loaded from another
+// file, proto rule generation is disabled.
+func InferProtoMode(c *Config, rel string, f *bf.File, directives []Directive) *Config {
+	if c.ProtoMode != DefaultProtoMode || c.ProtoModeExplicit {
+		return c
+	}
+	for _, d := range directives {
+		if d.Key == "proto" {
+			return c
+		}
+	}
+	if c.GoPrefix == WellKnownTypesGoPrefix {
+		// Use legacy mode in this repo. We don't need proto_library or
+		// go_proto_library, since we get that from @com_google_protobuf.
+		// Legacy rules still refer to .proto files in here, which need are
+		// exposed by filegroup. go_library rules from .pb.go files will be
+		// generated, which are depended upon by the new rules.
+		modified := *c
+		modified.ProtoMode = LegacyProtoMode
+		return &modified
+	}
+	if path.Base(rel) == "vendor" {
+		modified := *c
+		modified.ProtoMode = DisableProtoMode
+		return &modified
+	}
+	if f == nil {
+		return c
+	}
+	mode := DefaultProtoMode
+	for _, stmt := range f.Stmt {
+		c, ok := stmt.(*bf.CallExpr)
+		if !ok {
+			continue
+		}
+		x, ok := c.X.(*bf.LiteralExpr)
+		if !ok || x.Token != "load" || len(c.List) == 0 {
+			continue
+		}
+		name, ok := c.List[0].(*bf.StringExpr)
+		if !ok {
+			continue
+		}
+		if name.Value == "@io_bazel_rules_go//proto:def.bzl" {
+			break
+		}
+		if name.Value == "@io_bazel_rules_go//proto:go_proto_library.bzl" {
+			mode = LegacyProtoMode
+			break
+		}
+		for _, arg := range c.List[1:] {
+			if sym, ok := arg.(*bf.StringExpr); ok && sym.Value == "go_proto_library" {
+				mode = DisableProtoMode
+				break
+			}
+			kwarg, ok := arg.(*bf.BinaryExpr)
+			if !ok || kwarg.Op != "=" {
+				continue
+			}
+			if key, ok := kwarg.X.(*bf.LiteralExpr); ok && key.Token == "go_proto_library" {
+				mode = DisableProtoMode
+				break
+			}
+		}
+	}
+	if mode == DefaultProtoMode || c.ProtoMode == mode || c.ShouldFix && mode == LegacyProtoMode {
+		return c
+	}
+	modified := *c
+	modified.ProtoMode = mode
+	return &modified
+}

vendor/github.com/bazelbuild/bazel-gazelle/internal/config/platform.go

@@ -0,0 +1,128 @@
+/* Copyright 2017 The Bazel Authors. All rights reserved.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+   http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package config
+
+import (
+	"sort"
+)
+
+// Platform represents a GOOS/GOARCH pair. When Platform is used to describe
+// sources, dependencies, or flags, either OS or Arch may be empty.
+type Platform struct {
+	OS, Arch string
+}
+
+// String returns OS, Arch, or "OS_Arch" if both are set. This must match
+// the names of config_setting rules in @io_bazel_rules_go//go/platform.
+func (p Platform) String() string {
+	switch {
+	case p.OS != "" && p.Arch != "":
+		return p.OS + "_" + p.Arch
+	case p.OS != "":
+		return p.OS
+	case p.Arch != "":
+		return p.Arch
+	default:
+		return ""
+	}
+}
+
+// KnownPlatforms is the set of target platforms that Go supports. Gazelle
+// will generate multi-platform build files using these tags. rules_go and
+// Bazel may not actually support all of these.
+var KnownPlatforms = []Platform{
+	{"android", "386"},
+	{"android", "amd64"},
+	{"android", "arm"},
+	{"android", "arm64"},
+	{"darwin", "386"},
+	{"darwin", "amd64"},
+	{"darwin", "arm"},
+	{"darwin", "arm64"},
+	{"dragonfly", "amd64"},
+	{"freebsd", "386"},
+	{"freebsd", "amd64"},
+	{"freebsd", "arm"},
+	{"linux", "386"},
+	{"linux", "amd64"},
+	{"linux", "arm"},
+	{"linux", "arm64"},
+	{"linux", "mips"},
+	{"linux", "mips64"},
+	{"linux", "mips64le"},
+	{"linux", "mipsle"},
+	{"linux", "ppc64"},
+	{"linux", "ppc64le"},
+	{"linux", "s390x"},
+	{"nacl", "386"},
+	{"nacl", "amd64p32"},
+	{"nacl", "arm"},
+	{"netbsd", "386"},
+	{"netbsd", "amd64"},
+	{"netbsd", "arm"},
+	{"openbsd", "386"},
+	{"openbsd", "amd64"},
+	{"openbsd", "arm"},
+	{"plan9", "386"},
+	{"plan9", "amd64"},
+	{"plan9", "arm"},
+	{"solaris", "amd64"},
+	{"windows", "386"},
+	{"windows", "amd64"},
+}
+
+var (
+	// KnownOSs is the sorted list of operating systems that Go supports.
+	KnownOSs []string
+
+	// KnownOSSet is the set of operating systems that Go supports.
+	KnownOSSet map[string]bool
+
+	// KnownArchs is the sorted list of architectures that Go supports.
+	KnownArchs []string
+
+	// KnownArchSet is the set of architectures that Go supports.
+	KnownArchSet map[string]bool
+
+	// KnownOSArchs is a map from OS to the archictures they run on.
+	KnownOSArchs map[string][]string
+
+	// KnownArchOSs is a map from architectures to that OSs that run on them.
+	KnownArchOSs map[string][]string
+)
+
+func init() {
+	KnownOSSet = make(map[string]bool)
+	KnownArchSet = make(map[string]bool)
+	KnownOSArchs = make(map[string][]string)
+	KnownArchOSs = make(map[string][]string)
+	for _, p := range KnownPlatforms {
+		KnownOSSet[p.OS] = true
+		KnownArchSet[p.Arch] = true
+		KnownOSArchs[p.OS] = append(KnownOSArchs[p.OS], p.Arch)
+		KnownArchOSs[p.Arch] = append(KnownArchOSs[p.Arch], p.OS)
+	}
+	KnownOSs = make([]string, 0, len(KnownOSSet))
+	KnownArchs = make([]string, 0, len(KnownArchSet))
+	for os := range KnownOSSet {
+		KnownOSs = append(KnownOSs, os)
+	}
+	for arch := range KnownArchSet {
+		KnownArchs = append(KnownArchs, arch)
+	}
+	sort.Strings(KnownOSs)
+	sort.Strings(KnownArchs)
+}

vendor/github.com/bazelbuild/bazel-gazelle/internal/label/BUILD

@@ -0,0 +1,29 @@
+load("@io_bazel_rules_go//go:def.bzl", "go_library")
+
+go_library(
+    name = "go_default_library",
+    srcs = [
+        "label.go",
+        "labeler.go",
+    ],
+    importpath = "github.com/bazelbuild/bazel-gazelle/internal/label",
+    visibility = ["//vendor/github.com/bazelbuild/bazel-gazelle:__subpackages__"],
+    deps = [
+        "//vendor/github.com/bazelbuild/bazel-gazelle/internal/config:go_default_library",
+        "//vendor/github.com/bazelbuild/bazel-gazelle/internal/pathtools:go_default_library",
+    ],
+)
+
+filegroup(
+    name = "package-srcs",
+    srcs = glob(["**"]),
+    tags = ["automanaged"],
+    visibility = ["//visibility:private"],
+)
+
+filegroup(
+    name = "all-srcs",
+    srcs = [":package-srcs"],
+    tags = ["automanaged"],
+    visibility = ["//visibility:public"],
+)

vendor/github.com/bazelbuild/bazel-gazelle/internal/label/label.go

@@ -0,0 +1,163 @@
+/* Copyright 2016 The Bazel Authors. All rights reserved.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+   http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package label
+
+import (
+	"fmt"
+	"log"
+	"path"
+	"regexp"
+	"strings"
+
+	"github.com/bazelbuild/bazel-gazelle/internal/pathtools"
+)
+
+// A Label represents a label of a build target in Bazel.
+type Label struct {
+	Repo, Pkg, Name string
+	Relative        bool
+}
+
+func New(repo, pkg, name string) Label {
+	return Label{Repo: repo, Pkg: pkg, Name: name}
+}
+
+// NoLabel is the nil value of Label. It is not a valid label and may be
+// returned when an error occurs.
+var NoLabel = Label{}
+
+var (
+	labelRepoRegexp = regexp.MustCompile(`^[A-Za-z][A-Za-z0-9_]*$`)
+	labelPkgRegexp  = regexp.MustCompile(`^[A-Za-z0-9/._-]*$`)
+	labelNameRegexp = regexp.MustCompile(`^[A-Za-z0-9_/.+=,@~-]*$`)
+)
+
+// Parse reads a label from a string.
+// See https://docs.bazel.build/versions/master/build-ref.html#lexi.
+func Parse(s string) (Label, error) {
+	origStr := s
+
+	relative := true
+	var repo string
+	if strings.HasPrefix(s, "@") {
+		relative = false
+		endRepo := strings.Index(s, "//")
+		if endRepo < 0 {
+			return NoLabel, fmt.Errorf("label parse error: repository does not end with '//': %q", origStr)
+		}
+		repo = s[len("@"):endRepo]
+		if !labelRepoRegexp.MatchString(repo) {
+			return NoLabel, fmt.Errorf("label parse error: repository has invalid characters: %q", origStr)
+		}
+		s = s[endRepo:]
+	}
+
+	var pkg string
+	if strings.HasPrefix(s, "//") {
+		relative = false
+		endPkg := strings.Index(s, ":")
+		if endPkg < 0 {
+			pkg = s[len("//"):]
+			s = ""
+		} else {
+			pkg = s[len("//"):endPkg]
+			s = s[endPkg:]
+		}
+		if !labelPkgRegexp.MatchString(pkg) {
+			return NoLabel, fmt.Errorf("label parse error: package has invalid characters: %q", origStr)
+		}
+	}
+
+	if s == ":" {
+		return NoLabel, fmt.Errorf("label parse error: empty name: %q", origStr)
+	}
+	name := strings.TrimPrefix(s, ":")
+	if !labelNameRegexp.MatchString(name) {
+		return NoLabel, fmt.Errorf("label parse error: name has invalid characters: %q", origStr)
+	}
+
+	if pkg == "" && name == "" {
+		return NoLabel, fmt.Errorf("label parse error: empty package and name: %q", origStr)
+	}
+	if name == "" {
+		name = path.Base(pkg)
+	}
+
+	return Label{
+		Repo:     repo,
+		Pkg:      pkg,
+		Name:     name,
+		Relative: relative,
+	}, nil
+}
+
+func (l Label) String() string {
+	if l.Relative {
+		return fmt.Sprintf(":%s", l.Name)
+	}
+
+	var repo string
+	if l.Repo != "" {
+		repo = fmt.Sprintf("@%s", l.Repo)
+	}
+
+	if path.Base(l.Pkg) == l.Name {
+		return fmt.Sprintf("%s//%s", repo, l.Pkg)
+	}
+	return fmt.Sprintf("%s//%s:%s", repo, l.Pkg, l.Name)
+}
+
+func (l Label) Abs(repo, pkg string) Label {
+	if !l.Relative {
+		return l
+	}
+	return Label{Repo: repo, Pkg: pkg, Name: l.Name}
+}
+
+func (l Label) Equal(other Label) bool {
+	return l.Repo == other.Repo &&
+		l.Pkg == other.Pkg &&
+		l.Name == other.Name &&
+		l.Relative == other.Relative
+}
+
+// Contains returns whether other is contained by the package of l or a
+// sub-package. Neither label may be relative.
+func (l Label) Contains(other Label) bool {
+	if l.Relative {
+		log.Panicf("l must not be relative: %s", l)
+	}
+	if other.Relative {
+		log.Panicf("other must not be relative: %s", other)
+	}
+	result := l.Repo == other.Repo && pathtools.HasPrefix(other.Pkg, l.Pkg)
+	return result
+}
+
+// ImportPathToBazelRepoName converts a Go import path into a bazel repo name
+// following the guidelines in http://bazel.io/docs/be/functions.html#workspace
+func ImportPathToBazelRepoName(importpath string) string {
+	importpath = strings.ToLower(importpath)
+	components := strings.Split(importpath, "/")
+	labels := strings.Split(components[0], ".")
+	var reversed []string
+	for i := range labels {
+		l := labels[len(labels)-i-1]
+		reversed = append(reversed, l)
+	}
+	repo := strings.Join(append(reversed, components[1:]...), "_")
+	return strings.NewReplacer("-", "_", ".", "_").Replace(repo)
+}

vendor/github.com/bazelbuild/bazel-gazelle/internal/label/labeler.go

@@ -0,0 +1,58 @@
+/* Copyright 2017 The Bazel Authors. All rights reserved.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+   http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package label
+
+import (
+	"github.com/bazelbuild/bazel-gazelle/internal/config"
+	"github.com/bazelbuild/bazel-gazelle/internal/pathtools"
+)
+
+// Labeler generates Bazel labels for rules, based on their locations
+// within the repository.
+type Labeler struct {
+	c *config.Config
+}
+
+func NewLabeler(c *config.Config) *Labeler {
+	return &Labeler{c}
+}
+
+func (l *Labeler) LibraryLabel(rel string) Label {
+	return Label{Pkg: rel, Name: config.DefaultLibName}
+}
+
+func (l *Labeler) TestLabel(rel string, isXTest bool) Label {
+	var name string
+	if isXTest {
+		name = config.DefaultXTestName
+	} else {
+		name = config.DefaultTestName
+	}
+	return Label{Pkg: rel, Name: name}
+}
+
+func (l *Labeler) BinaryLabel(rel string) Label {
+	name := pathtools.RelBaseName(rel, l.c.GoPrefix, l.c.RepoRoot)
+	return Label{Pkg: rel, Name: name}
+}
+
+func (l *Labeler) ProtoLabel(rel, name string) Label {
+	return Label{Pkg: rel, Name: name + "_proto"}
+}
+
+func (l *Labeler) GoProtoLabel(rel, name string) Label {
+	return Label{Pkg: rel, Name: name + "_go_proto"}
+}

vendor/github.com/bazelbuild/bazel-gazelle/internal/merger/BUILD

@@ -0,0 +1,30 @@
+load("@io_bazel_rules_go//go:def.bzl", "go_library")
+
+go_library(
+    name = "go_default_library",
+    srcs = [
+        "fix.go",
+        "merger.go",
+    ],
+    importpath = "github.com/bazelbuild/bazel-gazelle/internal/merger",
+    visibility = ["//vendor/github.com/bazelbuild/bazel-gazelle:__subpackages__"],
+    deps = [
+        "//vendor/github.com/bazelbuild/bazel-gazelle/internal/config:go_default_library",
+        "//vendor/github.com/bazelbuild/bazel-gazelle/internal/label:go_default_library",
+        "//vendor/github.com/bazelbuild/buildtools/build:go_default_library",
+    ],
+)
+
+filegroup(
+    name = "package-srcs",
+    srcs = glob(["**"]),
+    tags = ["automanaged"],
+    visibility = ["//visibility:private"],
+)
+
+filegroup(
+    name = "all-srcs",
+    srcs = [":package-srcs"],
+    tags = ["automanaged"],
+    visibility = ["//visibility:public"],
+)

vendor/github.com/bazelbuild/bazel-gazelle/internal/merger/fix.go

@@ -0,0 +1,665 @@
+/* Copyright 2017 The Bazel Authors. All rights reserved.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+   http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package merger
+
+import (
+	"log"
+	"sort"
+
+	"github.com/bazelbuild/bazel-gazelle/internal/config"
+	bf "github.com/bazelbuild/buildtools/build"
+)
+
+// Much of this file could be simplified by using
+// github.com/bazelbuild/buildtools/edit. However, through a transitive
+// dependency, that library depends on a proto in Bazel itself, which is
+// a 95MB download. Not worth it.
+
+// FixFile updates rules in oldFile that were generated by an older version of
+// Gazelle to a newer form that can be merged with freshly generated rules.
+//
+// FixLoads should be called after this, since it will fix load
+// statements that may be broken by transformations applied by this function.
+func FixFile(c *config.Config, oldFile *bf.File) *bf.File {
+	fixedFile := squashCgoLibrary(oldFile)
+	return removeLegacyProto(c, fixedFile)
+}
+
+// squashCgoLibrary removes cgo_library rules with the default name and
+// merges their attributes with go_library with the default name. If no
+// go_library rule exists, a new one will be created.
+//
+// Note that the library attribute is disregarded, so cgo_library and
+// go_library attributes will be squashed even if the cgo_library was unlinked.
+// MergeWithExisting will remove unused values and attributes later.
+func squashCgoLibrary(oldFile *bf.File) *bf.File {
+	// Find the default cgo_library and go_library rules.
+	var cgoLibrary, goLibrary bf.Rule
+	cgoLibraryIndex := -1
+	goLibraryIndex := -1
+
+	for i, stmt := range oldFile.Stmt {
+		c, ok := stmt.(*bf.CallExpr)
+		if !ok {
+			continue
+		}
+		r := bf.Rule{Call: c}
+		if r.Kind() == "cgo_library" && r.Name() == config.DefaultCgoLibName && !shouldKeep(c) {
+			if cgoLibrary.Call != nil {
+				log.Printf("%s: when fixing existing file, multiple cgo_library rules with default name found", oldFile.Path)
+				continue
+			}
+			cgoLibrary = r
+			cgoLibraryIndex = i
+			continue
+		}
+		if r.Kind() == "go_library" && r.Name() == config.DefaultLibName {
+			if goLibrary.Call != nil {
+				log.Printf("%s: when fixing existing file, multiple go_library rules with default name referencing cgo_library found", oldFile.Path)
+				continue
+			}
+			goLibrary = r
+			goLibraryIndex = i
+		}
+	}
+
+	if cgoLibrary.Call == nil {
+		return oldFile
+	}
+
+	// If go_library has a '# keep' comment, just delete cgo_library.
+	if goLibrary.Call != nil && shouldKeep(goLibrary.Call) {
+		fixedFile := *oldFile
+		fixedFile.Stmt = append(fixedFile.Stmt[:cgoLibraryIndex], fixedFile.Stmt[cgoLibraryIndex+1:]...)
+		return &fixedFile
+	}
+
+	// Copy the comments and attributes from cgo_library into go_library. If no
+	// go_library exists, create an empty one.
+	var fixedGoLibraryExpr bf.CallExpr
+	fixedGoLibrary := bf.Rule{Call: &fixedGoLibraryExpr}
+	if goLibrary.Call == nil {
+		fixedGoLibrary.SetKind("go_library")
+		fixedGoLibrary.SetAttr("name", &bf.StringExpr{Value: config.DefaultLibName})
+		if vis := cgoLibrary.Attr("visibility"); vis != nil {
+			fixedGoLibrary.SetAttr("visibility", vis)
+		}
+	} else {
+		fixedGoLibraryExpr = *goLibrary.Call
+		fixedGoLibraryExpr.List = append([]bf.Expr{}, goLibrary.Call.List...)
+	}
+
+	fixedGoLibrary.DelAttr("embed")
+	fixedGoLibrary.SetAttr("cgo", &bf.LiteralExpr{Token: "True"})
+
+	fixedGoLibraryExpr.Comments.Before = append(fixedGoLibraryExpr.Comments.Before, cgoLibrary.Call.Comments.Before...)
+	fixedGoLibraryExpr.Comments.Suffix = append(fixedGoLibraryExpr.Comments.Suffix, cgoLibrary.Call.Comments.Suffix...)
+	fixedGoLibraryExpr.Comments.After = append(fixedGoLibraryExpr.Comments.After, cgoLibrary.Call.Comments.After...)
+
+	for _, key := range []string{"cdeps", "clinkopts", "copts", "data", "deps", "gc_goopts", "srcs"} {
+		goLibraryAttr := fixedGoLibrary.Attr(key)
+		cgoLibraryAttr := cgoLibrary.Attr(key)
+		if cgoLibraryAttr == nil {
+			continue
+		}
+		if fixedAttr, err := squashExpr(goLibraryAttr, cgoLibraryAttr); err == nil {
+			fixedGoLibrary.SetAttr(key, fixedAttr)
+		}
+	}
+
+	// Rebuild the file with the cgo_library removed and the go_library replaced.
+	// If the go_library didn't already exist, it will replace cgo_library.
+	fixedFile := *oldFile
+	if goLibrary.Call == nil {
+		fixedFile.Stmt = append([]bf.Expr{}, oldFile.Stmt...)
+		fixedFile.Stmt[cgoLibraryIndex] = &fixedGoLibraryExpr
+	} else {
+		fixedFile.Stmt = append(oldFile.Stmt[:cgoLibraryIndex], oldFile.Stmt[cgoLibraryIndex+1:]...)
+		if goLibraryIndex > cgoLibraryIndex {
+			goLibraryIndex--
+		}
+		fixedFile.Stmt[goLibraryIndex] = &fixedGoLibraryExpr
+	}
+	return &fixedFile
+}
+
+// squashExpr combines two expressions. Unlike mergeExpr, squashExpr does not
+// discard information from an "old" expression. It does not sort or de-duplicate
+// elements. Any non-scalar expressions that mergeExpr understands can be
+// squashed.
+func squashExpr(x, y bf.Expr) (bf.Expr, error) {
+	xExprs, err := extractPlatformStringsExprs(x)
+	if err != nil {
+		return nil, err
+	}
+	yExprs, err := extractPlatformStringsExprs(y)
+	if err != nil {
+		return nil, err
+	}
+	squashedExprs, err := squashPlatformStringsExprs(xExprs, yExprs)
+	if err != nil {
+		return nil, err
+	}
+	return makePlatformStringsExpr(squashedExprs), nil
+}
+
+func squashPlatformStringsExprs(x, y platformStringsExprs) (platformStringsExprs, error) {
+	var ps platformStringsExprs
+	var err error
+	ps.generic = squashList(x.generic, y.generic)
+	if ps.os, err = squashDict(x.os, y.os); err != nil {
+		return platformStringsExprs{}, err
+	}
+	if ps.arch, err = squashDict(x.arch, y.arch); err != nil {
+		return platformStringsExprs{}, err
+	}
+	if ps.platform, err = squashDict(x.platform, y.platform); err != nil {
+		return platformStringsExprs{}, err
+	}
+	return ps, nil
+}
+
+func squashList(x, y *bf.ListExpr) *bf.ListExpr {
+	if x == nil {
+		return y
+	}
+	if y == nil {
+		return x
+	}
+	squashed := *x
+	squashed.Comments.Before = append(x.Comments.Before, y.Comments.Before...)
+	squashed.Comments.Suffix = append(x.Comments.Suffix, y.Comments.Suffix...)
+	squashed.Comments.After = append(x.Comments.After, y.Comments.After...)
+	squashed.List = append(x.List, y.List...)
+	return &squashed
+}
+
+func squashDict(x, y *bf.DictExpr) (*bf.DictExpr, error) {
+	if x == nil {
+		return y, nil
+	}
+	if y == nil {
+		return x, nil
+	}
+
+	squashed := *x
+	squashed.Comments.Before = append(x.Comments.Before, y.Comments.Before...)
+	squashed.Comments.Suffix = append(x.Comments.Suffix, y.Comments.Suffix...)
+	squashed.Comments.After = append(x.Comments.After, y.Comments.After...)
+
+	xCaseIndex := make(map[string]int)
+	for i, e := range x.List {
+		kv, ok := e.(*bf.KeyValueExpr)
+		if !ok {
+			continue
+		}
+		key, ok := kv.Key.(*bf.StringExpr)
+		if !ok {
+			continue
+		}
+		xCaseIndex[key.Value] = i
+	}
+
+	for _, e := range y.List {
+		kv, ok := e.(*bf.KeyValueExpr)
+		if !ok {
+			squashed.List = append(squashed.List, e)
+			continue
+		}
+		key, ok := e.(*bf.StringExpr)
+		if !ok {
+			squashed.List = append(squashed.List, e)
+			continue
+		}
+		i, ok := xCaseIndex[key.Value]
+		if !ok {
+			squashed.List = append(squashed.List, e)
+			continue
+		}
+		squashedElem, err := squashExpr(x.List[i], kv.Value)
+		if err != nil {
+			return nil, err
+		}
+		x.List[i] = squashedElem
+	}
+
+	return &squashed, nil
+}
+
+// removeLegacyProto removes uses of the old proto rules. It deletes loads
+// from go_proto_library.bzl. It deletes proto filegroups. It removes
+// go_proto_library attributes which are no longer recognized. New rules
+// are generated in place of the deleted rules, but attributes and comments
+// are not migrated.
+func removeLegacyProto(c *config.Config, oldFile *bf.File) *bf.File {
+	// Don't fix if the proto mode was set to something other than the default.
+	if c.ProtoMode != config.DefaultProtoMode {
+		return oldFile
+	}
+
+	// Scan for definitions to delete.
+	var deletedIndices []int
+	var protoIndices []int
+	shouldDeleteProtos := false
+	for i, stmt := range oldFile.Stmt {
+		c, ok := stmt.(*bf.CallExpr)
+		if !ok {
+			continue
+		}
+		x, ok := c.X.(*bf.LiteralExpr)
+		if !ok {
+			continue
+		}
+
+		if x.Token == "load" && len(c.List) > 0 {
+			if name, ok := c.List[0].(*bf.StringExpr); ok && name.Value == "@io_bazel_rules_go//proto:go_proto_library.bzl" {
+				deletedIndices = append(deletedIndices, i)
+				shouldDeleteProtos = true
+			}
+			continue
+		}
+		if x.Token == "filegroup" {
+			r := bf.Rule{Call: c}
+			if r.Name() == config.DefaultProtosName {
+				deletedIndices = append(deletedIndices, i)
+			}
+			continue
+		}
+		if x.Token == "go_proto_library" {
+			protoIndices = append(protoIndices, i)
+		}
+	}
+	if len(deletedIndices) == 0 {
+		return oldFile
+	}
+
+	// Rebuild the file without deleted statements. Only delete go_proto_library
+	// rules if we deleted a load.
+	if shouldDeleteProtos {
+		deletedIndices = append(deletedIndices, protoIndices...)
+		sort.Ints(deletedIndices)
+	}
+	fixedFile := *oldFile
+	fixedFile.Stmt = deleteIndices(oldFile.Stmt, deletedIndices)
+	return &fixedFile
+}
+
+// FixFileMinor updates rules in oldFile that were generated by an older version
+// of Gazelle to a newer form that can be merged with freshly generated rules.
+//
+// FixFileMinor includes only small, low-risk fixes that can be applied in
+// update mode. When both FixFileMinor and FixFile are called, FixFileMinor
+// should be called first.
+//
+// FixLoads should be called after this, since it will fix load
+// statements that may be broken by transformations applied by this function.
+func FixFileMinor(c *config.Config, oldFile *bf.File) *bf.File {
+	fixedFile := migrateLibraryEmbed(c, oldFile)
+	fixedFile = migrateGrpcCompilers(c, fixedFile)
+	return removeBinaryImportPath(c, fixedFile)
+}
+
+// migrateLibraryEmbed converts "library" attributes to "embed" attributes,
+// preserving comments. This only applies to Go rules, and only if there is
+// no keep comment on "library" and no existing "embed" attribute.
+func migrateLibraryEmbed(c *config.Config, oldFile *bf.File) *bf.File {
+	fixed := false
+	fixedFile := *oldFile
+	for i, stmt := range fixedFile.Stmt {
+		call, ok := stmt.(*bf.CallExpr)
+		if !ok {
+			continue
+		}
+		rule := bf.Rule{Call: call}
+		if kind := rule.Kind(); !isGoRule(kind) || shouldKeep(stmt) {
+			continue
+		}
+		libExpr := rule.Attr("library")
+		if libExpr == nil || shouldKeep(libExpr) || rule.Attr("embed") != nil {
+			continue
+		}
+
+		fixedCall := *call
+		rule.Call = &fixedCall
+		rule.DelAttr("library")
+		rule.SetAttr("embed", &bf.ListExpr{List: []bf.Expr{libExpr}})
+		fixedFile.Stmt[i] = &fixedCall
+		fixed = true
+	}
+	if !fixed {
+		return oldFile
+	}
+	return &fixedFile
+}
+
+// migrateGrpcCompilers converts "go_grpc_library" rules into "go_proto_library"
+// rules with a "compilers" attribute.
+func migrateGrpcCompilers(c *config.Config, oldFile *bf.File) *bf.File {
+	fixed := false
+	fixedFile := *oldFile
+	for i, stmt := range fixedFile.Stmt {
+		call, ok := stmt.(*bf.CallExpr)
+		if !ok {
+			continue
+		}
+		rule := bf.Rule{Call: call}
+		if rule.Kind() != "go_grpc_library" || shouldKeep(stmt) || rule.Attr("compilers") != nil {
+			continue
+		}
+
+		fixedCall := *call
+		fixedCall.List = make([]bf.Expr, len(call.List))
+		copy(fixedCall.List, call.List)
+		rule.Call = &fixedCall
+		rule.SetKind("go_proto_library")
+		rule.SetAttr("compilers", &bf.ListExpr{
+			List: []bf.Expr{&bf.StringExpr{Value: config.GrpcCompilerLabel}},
+		})
+		fixedFile.Stmt[i] = &fixedCall
+		fixed = true
+	}
+	if !fixed {
+		return oldFile
+	}
+	return &fixedFile
+}
+
+// removeBinaryImportPath removes "importpath" attributes from "go_binary"
+// and "go_test" rules. These are now deprecated.
+func removeBinaryImportPath(c *config.Config, oldFile *bf.File) *bf.File {
+	fixed := false
+	fixedFile := *oldFile
+	for i, stmt := range fixedFile.Stmt {
+		call, ok := stmt.(*bf.CallExpr)
+		if !ok {
+			continue
+		}
+		rule := bf.Rule{Call: call}
+		if rule.Kind() != "go_binary" && rule.Kind() != "go_test" || rule.Attr("importpath") == nil {
+			continue
+		}
+
+		fixedCall := *call
+		fixedCall.List = make([]bf.Expr, len(call.List))
+		copy(fixedCall.List, call.List)
+		rule.Call = &fixedCall
+		rule.DelAttr("importpath")
+		fixedFile.Stmt[i] = &fixedCall
+		fixed = true
+	}
+	if !fixed {
+		return oldFile
+	}
+	return &fixedFile
+}
+
+// FixLoads removes loads of unused go rules and adds loads of newly used rules.
+// This should be called after FixFile and MergeWithExisting, since symbols
+// may be introduced that aren't loaded.
+func FixLoads(oldFile *bf.File) *bf.File {
+	// Make a list of load statements in the file. Keep track of loads of known
+	// files, since these may be changed. Keep track of known symbols loaded from
+	// unknown files; we will not add loads for these.
+	type loadInfo struct {
+		index      int
+		file       string
+		old, fixed *bf.CallExpr
+	}
+	var loads []loadInfo
+	otherLoadedKinds := make(map[string]bool)
+	for i, stmt := range oldFile.Stmt {
+		c, ok := stmt.(*bf.CallExpr)
+		if !ok {
+			continue
+		}
+		x, ok := c.X.(*bf.LiteralExpr)
+		if !ok || x.Token != "load" {
+			continue
+		}
+
+		if len(c.List) == 0 {
+			continue
+		}
+		label, ok := c.List[0].(*bf.StringExpr)
+		if !ok {
+			continue
+		}
+
+		if knownFiles[label.Value] {
+			loads = append(loads, loadInfo{index: i, file: label.Value, old: c})
+			continue
+		}
+		for _, arg := range c.List[1:] {
+			switch sym := arg.(type) {
+			case *bf.StringExpr:
+				otherLoadedKinds[sym.Value] = true
+			case *bf.BinaryExpr:
+				if sym.Op != "=" {
+					continue
+				}
+				if x, ok := sym.X.(*bf.LiteralExpr); ok {
+					otherLoadedKinds[x.Token] = true
+				}
+			}
+		}
+	}
+
+	// Make a map of all the symbols from known files used in this file.
+	usedKinds := make(map[string]map[string]bool)
+	for _, stmt := range oldFile.Stmt {
+		c, ok := stmt.(*bf.CallExpr)
+		if !ok {
+			continue
+		}
+		x, ok := c.X.(*bf.LiteralExpr)
+		if !ok {
+			continue
+		}
+
+		kind := x.Token
+		if file, ok := knownKinds[kind]; ok && !otherLoadedKinds[kind] {
+			if usedKinds[file] == nil {
+				usedKinds[file] = make(map[string]bool)
+			}
+			usedKinds[file][kind] = true
+		}
+	}
+
+	// Fix the load statements. The order is important, so we iterate over
+	// knownLoads instead of knownFiles.
+	changed := false
+	var newFirstLoads []*bf.CallExpr
+	for _, l := range knownLoads {
+		file := l.file
+		first := true
+		for i, _ := range loads {
+			li := &loads[i]
+			if li.file != file {
+				continue
+			}
+			if first {
+				li.fixed = fixLoad(li.old, file, usedKinds[file])
+				first = false
+			} else {
+				li.fixed = fixLoad(li.old, file, nil)
+			}
+			changed = changed || li.fixed != li.old
+		}
+		if first {
+			load := fixLoad(nil, file, usedKinds[file])
+			if load != nil {
+				newFirstLoads = append(newFirstLoads, load)
+				changed = true
+			}
+		}
+	}
+	if !changed {
+		return oldFile
+	}
+
+	// Rebuild the file.
+	fixedFile := *oldFile
+	fixedFile.Stmt = make([]bf.Expr, 0, len(oldFile.Stmt)+len(newFirstLoads))
+	for _, l := range newFirstLoads {
+		fixedFile.Stmt = append(fixedFile.Stmt, l)
+	}
+	loadIndex := 0
+	for i, stmt := range oldFile.Stmt {
+		if loadIndex < len(loads) && i == loads[loadIndex].index {
+			if loads[loadIndex].fixed != nil {
+				fixedFile.Stmt = append(fixedFile.Stmt, loads[loadIndex].fixed)
+			}
+			loadIndex++
+			continue
+		}
+		fixedFile.Stmt = append(fixedFile.Stmt, stmt)
+	}
+	return &fixedFile
+}
+
+// knownLoads is a list of files Gazelle will generate loads from and
+// the symbols it knows about.  All symbols Gazelle ever generated
+// loads for are present, including symbols it no longer uses (e.g.,
+// cgo_library). Manually loaded symbols (e.g., go_embed_data) are not
+// included. The order of the files here will match the order of
+// generated load statements. The symbols should be sorted
+// lexicographically.
+var knownLoads = []struct {
+	file  string
+	kinds []string
+}{
+	{
+		"@io_bazel_rules_go//go:def.bzl",
+		[]string{
+			"cgo_library",
+			"go_binary",
+			"go_library",
+			"go_prefix",
+			"go_repository",
+			"go_test",
+		},
+	}, {
+		"@io_bazel_rules_go//proto:def.bzl",
+		[]string{
+			"go_grpc_library",
+			"go_proto_library",
+		},
+	},
+}
+
+// knownFiles is the set of labels for files that Gazelle loads symbols from.
+var knownFiles map[string]bool
+
+// knownKinds is a map from symbols to labels of the files they are loaded
+// from.
+var knownKinds map[string]string
+
+func init() {
+	knownFiles = make(map[string]bool)
+	knownKinds = make(map[string]string)
+	for _, l := range knownLoads {
+		knownFiles[l.file] = true
+		for _, k := range l.kinds {
+			knownKinds[k] = l.file
+		}
+	}
+}
+
+// fixLoad updates a load statement. load must be a load statement for
+// the Go rules or nil. If nil, a new statement may be created. Symbols in
+// kinds are added if they are not already present, symbols in knownKinds
+// are removed if they are not in kinds, and other symbols and arguments
+// are preserved. nil is returned if the statement should be deleted because
+// it is empty.
+func fixLoad(load *bf.CallExpr, file string, kinds map[string]bool) *bf.CallExpr {
+	var fixed bf.CallExpr
+	if load == nil {
+		fixed = bf.CallExpr{
+			X: &bf.LiteralExpr{Token: "load"},
+			List: []bf.Expr{
+				&bf.StringExpr{Value: file},
+			},
+			ForceCompact: true,
+		}
+	} else {
+		fixed = *load
+	}
+
+	var symbols []*bf.StringExpr
+	var otherArgs []bf.Expr
+	loadedKinds := make(map[string]bool)
+	var added, removed int
+	for _, arg := range fixed.List[1:] {
+		if s, ok := arg.(*bf.StringExpr); ok {
+			if knownKinds[s.Value] == "" || kinds != nil && kinds[s.Value] {
+				symbols = append(symbols, s)
+				loadedKinds[s.Value] = true
+			} else {
+				removed++
+			}
+		} else {
+			otherArgs = append(otherArgs, arg)
+		}
+	}
+	if kinds != nil {
+		for kind, _ := range kinds {
+			if _, ok := loadedKinds[kind]; !ok {
+				symbols = append(symbols, &bf.StringExpr{Value: kind})
+				added++
+			}
+		}
+	}
+	if added == 0 && removed == 0 {
+		if load != nil && len(load.List) == 1 {
+			// Special case: delete existing empty load.
+			return nil
+		}
+		return load
+	}
+
+	sort.Stable(byString(symbols))
+	fixed.List = fixed.List[:1]
+	for _, sym := range symbols {
+		fixed.List = append(fixed.List, sym)
+	}
+	fixed.List = append(fixed.List, otherArgs...)
+	if len(fixed.List) == 1 {
+		return nil
+	}
+	return &fixed
+}
+
+type byString []*bf.StringExpr
+
+func (s byString) Len() int {
+	return len(s)
+}
+
+func (s byString) Less(i, j int) bool {
+	return s[i].Value < s[j].Value
+}
+
+func (s byString) Swap(i, j int) {
+	s[i], s[j] = s[j], s[i]
+}
+
+func isGoRule(kind string) bool {
+	return kind == "go_library" ||
+		kind == "go_binary" ||
+		kind == "go_test" ||
+		kind == "go_proto_library" ||
+		kind == "go_grpc_library"
+}

vendor/github.com/bazelbuild/bazel-gazelle/internal/merger/merger.go

@@ -0,0 +1,926 @@
+/* Copyright 2016 The Bazel Authors. All rights reserved.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+   http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+// Package merger provides methods for merging parsed BUILD files.
+package merger
+
+import (
+	"fmt"
+	"log"
+	"sort"
+	"strings"
+
+	"github.com/bazelbuild/bazel-gazelle/internal/config"
+	"github.com/bazelbuild/bazel-gazelle/internal/label"
+	bf "github.com/bazelbuild/buildtools/build"
+)
+
+const keep = "keep" // marker in srcs or deps to tell gazelle to preserve.
+
+// MergableAttrs is the set of attribute names for each kind of rule that
+// may be merged. When an attribute is mergeable, a generated value may
+// replace or augment an existing value. If an attribute is not mergeable,
+// existing values are preserved. Generated non-mergeable attributes may
+// still be added to a rule if there is no corresponding existing attribute.
+type MergeableAttrs map[string]map[string]bool
+
+var (
+	// PreResolveAttrs is the set of attributes that should be merged before
+	// dependency resolution, i.e., everything except deps.
+	PreResolveAttrs MergeableAttrs
+
+	// PostResolveAttrs is the set of attributes that should be merged after
+	// dependency resolution, i.e., deps.
+	PostResolveAttrs MergeableAttrs
+
+	// RepoAttrs is the set of attributes that should be merged in repository
+	// rules in WORKSPACE.
+	RepoAttrs MergeableAttrs
+
+	// nonEmptyAttrs is the set of attributes that disqualify a rule from being
+	// deleted after merge.
+	nonEmptyAttrs MergeableAttrs
+)
+
+func init() {
+	PreResolveAttrs = make(MergeableAttrs)
+	PostResolveAttrs = make(MergeableAttrs)
+	RepoAttrs = make(MergeableAttrs)
+	nonEmptyAttrs = make(MergeableAttrs)
+	for _, set := range []struct {
+		mergeableAttrs MergeableAttrs
+		kinds, attrs   []string
+	}{
+		{
+			mergeableAttrs: PreResolveAttrs,
+			kinds: []string{
+				"go_library",
+				"go_binary",
+				"go_test",
+				"go_proto_library",
+				"proto_library",
+			},
+			attrs: []string{
+				"srcs",
+			},
+		}, {
+			mergeableAttrs: PreResolveAttrs,
+			kinds: []string{
+				"go_library",
+				"go_proto_library",
+			},
+			attrs: []string{
+				"importpath",
+			},
+		}, {
+			mergeableAttrs: PreResolveAttrs,
+			kinds: []string{
+				"go_library",
+				"go_binary",
+				"go_test",
+				"go_proto_library",
+			},
+			attrs: []string{
+				"cgo",
+				"clinkopts",
+				"copts",
+				"embed",
+			},
+		}, {
+			mergeableAttrs: PreResolveAttrs,
+			kinds: []string{
+				"go_proto_library",
+			},
+			attrs: []string{
+				"proto",
+			},
+		}, {
+			mergeableAttrs: PostResolveAttrs,
+			kinds: []string{
+				"go_library",
+				"go_binary",
+				"go_test",
+				"go_proto_library",
+				"proto_library",
+			},
+			attrs: []string{
+				"deps",
+				config.GazelleImportsKey,
+			},
+		}, {
+			mergeableAttrs: RepoAttrs,
+			kinds: []string{
+				"go_repository",
+			},
+			attrs: []string{
+				"commit",
+				"importpath",
+				"remote",
+				"sha256",
+				"strip_prefix",
+				"tag",
+				"type",
+				"urls",
+				"vcs",
+			},
+		}, {
+			mergeableAttrs: nonEmptyAttrs,
+			kinds: []string{
+				"go_binary",
+				"go_library",
+				"go_test",
+				"proto_library",
+			},
+			attrs: []string{
+				"srcs",
+				"deps",
+			},
+		}, {
+			mergeableAttrs: nonEmptyAttrs,
+			kinds: []string{
+				"go_binary",
+				"go_library",
+				"go_test",
+			},
+			attrs: []string{
+				"embed",
+			},
+		}, {
+			mergeableAttrs: nonEmptyAttrs,
+			kinds: []string{
+				"go_proto_library",
+			},
+			attrs: []string{
+				"proto",
+			},
+		},
+	} {
+		for _, kind := range set.kinds {
+			if set.mergeableAttrs[kind] == nil {
+				set.mergeableAttrs[kind] = make(map[string]bool)
+			}
+			for _, attr := range set.attrs {
+				set.mergeableAttrs[kind][attr] = true
+			}
+		}
+	}
+}
+
+// MergeFile merges the rules in genRules with matching rules in oldFile and
+// adds unmatched rules to the end of the merged file. MergeFile also merges
+// rules in empty with matching rules in oldFile and deletes rules that
+// are empty after merging. attrs is the set of attributes to merge. Attributes
+// not in this set will be left alone if they already exist.
+func MergeFile(genRules []bf.Expr, empty []bf.Expr, oldFile *bf.File, attrs MergeableAttrs) (mergedFile *bf.File, mergedRules []bf.Expr) {
+	// Merge empty rules into the file and delete any rules which become empty.
+	mergedFile = new(bf.File)
+	*mergedFile = *oldFile
+	mergedFile.Stmt = append([]bf.Expr{}, oldFile.Stmt...)
+	var deletedIndices []int
+	for _, s := range empty {
+		emptyCall := s.(*bf.CallExpr)
+		if oldCall, i, _ := match(oldFile.Stmt, emptyCall); oldCall != nil {
+			mergedRule := mergeRule(emptyCall, oldCall, attrs, oldFile.Path)
+			if isRuleEmpty(mergedRule) {
+				deletedIndices = append(deletedIndices, i)
+			} else {
+				mergedFile.Stmt[i] = mergedRule
+			}
+		}
+	}
+	if len(deletedIndices) > 0 {
+		sort.Ints(deletedIndices)
+		mergedFile.Stmt = deleteIndices(mergedFile.Stmt, deletedIndices)
+	}
+
+	// Match generated rules with existing rules in the file. Keep track of
+	// rules with non-standard names.
+	matchIndices := make([]int, len(genRules))
+	matchErrors := make([]error, len(genRules))
+	substitutions := make(map[string]string)
+	for i, s := range genRules {
+		genCall := s.(*bf.CallExpr)
+		oldCall, oldIndex, err := match(mergedFile.Stmt, genCall)
+		if err != nil {
+			// TODO(jayconrod): add a verbose mode and log errors. They are too chatty
+			// to print by default.
+			matchErrors[i] = err
+			continue
+		}
+		matchIndices[i] = oldIndex // < 0 indicates no match
+		if oldCall != nil {
+			oldRule := bf.Rule{Call: oldCall}
+			genRule := bf.Rule{Call: genCall}
+			oldName := oldRule.Name()
+			genName := genRule.Name()
+			if oldName != genName {
+				substitutions[genName] = oldName
+			}
+		}
+	}
+
+	// Rename labels in generated rules that refer to other generated rules.
+	if len(substitutions) > 0 {
+		genRules = append([]bf.Expr{}, genRules...)
+		for i, s := range genRules {
+			genRules[i] = substituteRule(s.(*bf.CallExpr), substitutions)
+		}
+	}
+
+	// Merge generated rules with existing rules or append to the end of the file.
+	for i := range genRules {
+		if matchErrors[i] != nil {
+			continue
+		}
+		if matchIndices[i] < 0 {
+			mergedFile.Stmt = append(mergedFile.Stmt, genRules[i])
+			mergedRules = append(mergedRules, genRules[i])
+		} else {
+			mergedRule := mergeRule(genRules[i].(*bf.CallExpr), mergedFile.Stmt[matchIndices[i]].(*bf.CallExpr), attrs, oldFile.Path)
+			mergedFile.Stmt[matchIndices[i]] = mergedRule
+			mergedRules = append(mergedRules, mergedRule)
+		}
+	}
+
+	return mergedFile, mergedRules
+}
+
+// mergeRule combines information from gen and old and returns an updated rule.
+// Both rules must be non-nil and must have the same kind and same name.
+// attrs is the set of attributes which may be merged.
+// If nil is returned, the rule should be deleted.
+func mergeRule(gen, old *bf.CallExpr, attrs MergeableAttrs, filename string) bf.Expr {
+	if old != nil && shouldKeep(old) {
+		return old
+	}
+
+	genRule := bf.Rule{Call: gen}
+	oldRule := bf.Rule{Call: old}
+	merged := *old
+	merged.List = nil
+	mergedRule := bf.Rule{Call: &merged}
+
+	// Copy unnamed arguments from the old rule without merging. The only rule
+	// generated with unnamed arguments is go_prefix, which we currently
+	// leave in place.
+	// TODO: maybe gazelle should allow the prefix to be changed.
+	for _, a := range old.List {
+		if b, ok := a.(*bf.BinaryExpr); ok && b.Op == "=" {
+			break
+		}
+		merged.List = append(merged.List, a)
+	}
+
+	// Merge attributes from the old rule. Preserve comments on old attributes.
+	// Assume generated attributes have no comments.
+	kind := oldRule.Kind()
+	for _, k := range oldRule.AttrKeys() {
+		oldAttr := oldRule.AttrDefn(k)
+		if !attrs[kind][k] || shouldKeep(oldAttr) {
+			merged.List = append(merged.List, oldAttr)
+			continue
+		}
+
+		oldExpr := oldAttr.Y
+		genExpr := genRule.Attr(k)
+		mergedExpr, err := mergeExpr(genExpr, oldExpr)
+		if err != nil {
+			start, end := oldExpr.Span()
+			log.Printf("%s:%d.%d-%d.%d: could not merge expression", filename, start.Line, start.LineRune, end.Line, end.LineRune)
+			mergedExpr = oldExpr
+		}
+		if mergedExpr != nil {
+			mergedAttr := *oldAttr
+			mergedAttr.Y = mergedExpr
+			merged.List = append(merged.List, &mergedAttr)
+		}
+	}
+
+	// Merge attributes from genRule that we haven't processed already.
+	for _, k := range genRule.AttrKeys() {
+		if mergedRule.Attr(k) == nil {
+			mergedRule.SetAttr(k, genRule.Attr(k))
+		}
+	}
+
+	return &merged
+}
+
+// mergeExpr combines information from gen and old and returns an updated
+// expression. The following kinds of expressions are recognized:
+//
+//   * nil
+//   * strings (can only be merged with strings)
+//   * lists of strings
+//   * a call to select with a dict argument. The dict keys must be strings,
+//     and the values must be lists of strings.
+//   * a list of strings combined with a select call using +. The list must
+//     be the left operand.
+//
+// An error is returned if the expressions can't be merged, for example
+// because they are not in one of the above formats.
+func mergeExpr(gen, old bf.Expr) (bf.Expr, error) {
+	if shouldKeep(old) {
+		return old, nil
+	}
+	if gen == nil && (old == nil || isScalar(old)) {
+		return nil, nil
+	}
+	if isScalar(gen) {
+		return gen, nil
+	}
+
+	genExprs, err := extractPlatformStringsExprs(gen)
+	if err != nil {
+		return nil, err
+	}
+	oldExprs, err := extractPlatformStringsExprs(old)
+	if err != nil {
+		return nil, err
+	}
+	mergedExprs, err := mergePlatformStringsExprs(genExprs, oldExprs)
+	if err != nil {
+		return nil, err
+	}
+	return makePlatformStringsExpr(mergedExprs), nil
+}
+
+// platformStringsExprs is a set of sub-expressions that match the structure
+// of package.PlatformStrings. rules.Generator produces expressions that
+// follow this structure for srcs, deps, and other attributes, so this matches
+// all non-scalar expressions generated by Gazelle.
+//
+// The matched expression has the form:
+//
+// [] + select({}) + select({}) + select({})
+//
+// The four collections may appear in any order, and some or all of them may
+// be omitted (all fields are nil for a nil expression).
+type platformStringsExprs struct {
+	generic            *bf.ListExpr
+	os, arch, platform *bf.DictExpr
+}
+
+// extractPlatformStringsExprs matches an expression and attempts to extract
+// sub-expressions in platformStringsExprs. The sub-expressions can then be
+// merged with corresponding sub-expressions. Any field in the returned
+// structure may be nil. An error is returned if the given expression does
+// not follow the pattern described by platformStringsExprs.
+func extractPlatformStringsExprs(expr bf.Expr) (platformStringsExprs, error) {
+	var ps platformStringsExprs
+	if expr == nil {
+		return ps, nil
+	}
+
+	// Break the expression into a sequence of expressions combined with +.
+	var parts []bf.Expr
+	for {
+		binop, ok := expr.(*bf.BinaryExpr)
+		if !ok {
+			parts = append(parts, expr)
+			break
+		}
+		parts = append(parts, binop.Y)
+		expr = binop.X
+	}
+
+	// Process each part. They may be in any order.
+	for _, part := range parts {
+		switch part := part.(type) {
+		case *bf.ListExpr:
+			if ps.generic != nil {
+				return platformStringsExprs{}, fmt.Errorf("expression could not be matched: multiple list expressions")
+			}
+			ps.generic = part
+
+		case *bf.CallExpr:
+			x, ok := part.X.(*bf.LiteralExpr)
+			if !ok || x.Token != "select" || len(part.List) != 1 {
+				return platformStringsExprs{}, fmt.Errorf("expression could not be matched: callee other than select or wrong number of args")
+			}
+			arg, ok := part.List[0].(*bf.DictExpr)
+			if !ok {
+				return platformStringsExprs{}, fmt.Errorf("expression could not be matched: select argument not dict")
+			}
+			var dict **bf.DictExpr
+			for _, item := range arg.List {
+				kv := item.(*bf.KeyValueExpr) // parser guarantees this
+				k, ok := kv.Key.(*bf.StringExpr)
+				if !ok {
+					return platformStringsExprs{}, fmt.Errorf("expression could not be matched: dict keys are not all strings")
+				}
+				if k.Value == "//conditions:default" {
+					continue
+				}
+				key, err := label.Parse(k.Value)
+				if err != nil {
+					return platformStringsExprs{}, fmt.Errorf("expression could not be matched: dict key is not label: %q", k.Value)
+				}
+				if config.KnownOSSet[key.Name] {
+					dict = &ps.os
+					break
+				}
+				if config.KnownArchSet[key.Name] {
+					dict = &ps.arch
+					break
+				}
+				osArch := strings.Split(key.Name, "_")
+				if len(osArch) != 2 || !config.KnownOSSet[osArch[0]] || !config.KnownArchSet[osArch[1]] {
+					return platformStringsExprs{}, fmt.Errorf("expression could not be matched: dict key contains unknown platform: %q", k.Value)
+				}
+				dict = &ps.platform
+				break
+			}
+			if dict == nil {
+				// We could not identify the dict because it's empty or only contains
+				// //conditions:default. We'll call it the platform dict to avoid
+				// dropping it.
+				dict = &ps.platform
+			}
+			if *dict != nil {
+				return platformStringsExprs{}, fmt.Errorf("expression could not be matched: multiple selects that are either os-specific, arch-specific, or platform-specific")
+			}
+			*dict = arg
+		}
+	}
+	return ps, nil
+}
+
+// makePlatformStringsExpr constructs a single expression from the
+// sub-expressions in ps.
+func makePlatformStringsExpr(ps platformStringsExprs) bf.Expr {
+	makeSelect := func(dict *bf.DictExpr) bf.Expr {
+		return &bf.CallExpr{
+			X:    &bf.LiteralExpr{Token: "select"},
+			List: []bf.Expr{dict},
+		}
+	}
+	forceMultiline := func(e bf.Expr) {
+		switch e := e.(type) {
+		case *bf.ListExpr:
+			e.ForceMultiLine = true
+		case *bf.CallExpr:
+			e.List[0].(*bf.DictExpr).ForceMultiLine = true
+		}
+	}
+
+	var parts []bf.Expr
+	if ps.generic != nil {
+		parts = append(parts, ps.generic)
+	}
+	if ps.os != nil {
+		parts = append(parts, makeSelect(ps.os))
+	}
+	if ps.arch != nil {
+		parts = append(parts, makeSelect(ps.arch))
+	}
+	if ps.platform != nil {
+		parts = append(parts, makeSelect(ps.platform))
+	}
+
+	if len(parts) == 0 {
+		return nil
+	}
+	if len(parts) == 1 {
+		return parts[0]
+	}
+	expr := parts[0]
+	forceMultiline(expr)
+	for _, part := range parts[1:] {
+		forceMultiline(part)
+		expr = &bf.BinaryExpr{
+			Op: "+",
+			X:  expr,
+			Y:  part,
+		}
+	}
+	return expr
+}
+
+func mergePlatformStringsExprs(gen, old platformStringsExprs) (platformStringsExprs, error) {
+	var ps platformStringsExprs
+	var err error
+	ps.generic = mergeList(gen.generic, old.generic)
+	if ps.os, err = mergeDict(gen.os, old.os); err != nil {
+		return platformStringsExprs{}, err
+	}
+	if ps.arch, err = mergeDict(gen.arch, old.arch); err != nil {
+		return platformStringsExprs{}, err
+	}
+	if ps.platform, err = mergeDict(gen.platform, old.platform); err != nil {
+		return platformStringsExprs{}, err
+	}
+	return ps, nil
+}
+
+func mergeList(gen, old *bf.ListExpr) *bf.ListExpr {
+	if old == nil {
+		return gen
+	}
+	if gen == nil {
+		gen = &bf.ListExpr{List: []bf.Expr{}}
+	}
+
+	// Build a list of strings from the gen list and keep matching strings
+	// in the old list. This preserves comments. Also keep anything with
+	// a "# keep" comment, whether or not it's in the gen list.
+	genSet := make(map[string]bool)
+	for _, v := range gen.List {
+		if s := stringValue(v); s != "" {
+			genSet[s] = true
+		}
+	}
+
+	var merged []bf.Expr
+	kept := make(map[string]bool)
+	keepComment := false
+	for _, v := range old.List {
+		s := stringValue(v)
+		if keep := shouldKeep(v); keep || genSet[s] {
+			keepComment = keepComment || keep
+			merged = append(merged, v)
+			if s != "" {
+				kept[s] = true
+			}
+		}
+	}
+
+	// Add anything in the gen list that wasn't kept.
+	for _, v := range gen.List {
+		if s := stringValue(v); kept[s] {
+			continue
+		}
+		merged = append(merged, v)
+	}
+
+	if len(merged) == 0 {
+		return nil
+	}
+	return &bf.ListExpr{
+		List:           merged,
+		ForceMultiLine: gen.ForceMultiLine || old.ForceMultiLine || keepComment,
+	}
+}
+
+func mergeDict(gen, old *bf.DictExpr) (*bf.DictExpr, error) {
+	if old == nil {
+		return gen, nil
+	}
+	if gen == nil {
+		gen = &bf.DictExpr{List: []bf.Expr{}}
+	}
+
+	var entries []*dictEntry
+	entryMap := make(map[string]*dictEntry)
+
+	for _, kv := range old.List {
+		k, v, err := dictEntryKeyValue(kv)
+		if err != nil {
+			return nil, err
+		}
+		if _, ok := entryMap[k]; ok {
+			return nil, fmt.Errorf("old dict contains more than one case named %q", k)
+		}
+		e := &dictEntry{key: k, oldValue: v}
+		entries = append(entries, e)
+		entryMap[k] = e
+	}
+
+	for _, kv := range gen.List {
+		k, v, err := dictEntryKeyValue(kv)
+		if err != nil {
+			return nil, err
+		}
+		e, ok := entryMap[k]
+		if !ok {
+			e = &dictEntry{key: k}
+			entries = append(entries, e)
+			entryMap[k] = e
+		}
+		e.genValue = v
+	}
+
+	keys := make([]string, 0, len(entries))
+	haveDefault := false
+	for _, e := range entries {
+		e.mergedValue = mergeList(e.genValue, e.oldValue)
+		if e.key == "//conditions:default" {
+			// Keep the default case, even if it's empty.
+			haveDefault = true
+			if e.mergedValue == nil {
+				e.mergedValue = &bf.ListExpr{}
+			}
+		} else if e.mergedValue != nil {
+			keys = append(keys, e.key)
+		}
+	}
+	if len(keys) == 0 && (!haveDefault || len(entryMap["//conditions:default"].mergedValue.List) == 0) {
+		return nil, nil
+	}
+	sort.Strings(keys)
+	// Always put the default case last.
+	if haveDefault {
+		keys = append(keys, "//conditions:default")
+	}
+
+	mergedEntries := make([]bf.Expr, len(keys))
+	for i, k := range keys {
+		e := entryMap[k]
+		mergedEntries[i] = &bf.KeyValueExpr{
+			Key:   &bf.StringExpr{Value: e.key},
+			Value: e.mergedValue,
+		}
+	}
+
+	return &bf.DictExpr{List: mergedEntries, ForceMultiLine: true}, nil
+}
+
+type dictEntry struct {
+	key                             string
+	oldValue, genValue, mergedValue *bf.ListExpr
+}
+
+func dictEntryKeyValue(e bf.Expr) (string, *bf.ListExpr, error) {
+	kv, ok := e.(*bf.KeyValueExpr)
+	if !ok {
+		return "", nil, fmt.Errorf("dict entry was not a key-value pair: %#v", e)
+	}
+	k, ok := kv.Key.(*bf.StringExpr)
+	if !ok {
+		return "", nil, fmt.Errorf("dict key was not string: %#v", kv.Key)
+	}
+	v, ok := kv.Value.(*bf.ListExpr)
+	if !ok {
+		return "", nil, fmt.Errorf("dict value was not list: %#v", kv.Value)
+	}
+	return k.Value, v, nil
+}
+
+// substituteAttrs contains a list of attributes for each kind that should be
+// processed by substituteRule and substituteExpr. Note that "name" does not
+// need to be substituted since it's not mergeable.
+var substituteAttrs = map[string][]string{
+	"go_binary":        {"embed"},
+	"go_library":       {"embed"},
+	"go_test":          {"embed"},
+	"go_proto_library": {"proto"},
+}
+
+// substituteRule replaces local labels (those beginning with ":", referring to
+// targets in the same package) according to a substitution map. This is used
+// to update generated rules before merging when the corresponding existing
+// rules have different names. If substituteRule replaces a string, it returns
+// a new expression; it will not modify the original expression.
+func substituteRule(call *bf.CallExpr, substitutions map[string]string) *bf.CallExpr {
+	rule := bf.Rule{Call: call}
+	attrs, ok := substituteAttrs[rule.Kind()]
+	if !ok {
+		return call
+	}
+
+	didCopy := false
+	for i, arg := range call.List {
+		kv, ok := arg.(*bf.BinaryExpr)
+		if !ok || kv.Op != "=" {
+			continue
+		}
+		key, ok := kv.X.(*bf.LiteralExpr)
+		shouldRename := false
+		for _, k := range attrs {
+			shouldRename = shouldRename || key.Token == k
+		}
+		if !shouldRename {
+			continue
+		}
+
+		value := substituteExpr(kv.Y, substitutions)
+		if value != kv.Y {
+			if !didCopy {
+				didCopy = true
+				callCopy := *call
+				callCopy.List = append([]bf.Expr{}, call.List...)
+				call = &callCopy
+			}
+			kvCopy := *kv
+			kvCopy.Y = value
+			call.List[i] = &kvCopy
+		}
+	}
+	return call
+}
+
+// substituteExpr replaces local labels according to a substitution map.
+// It only supports string and list expressions (which should be sufficient
+// for generated rules). If it replaces a string, it returns a new expression;
+// otherwise, it returns e.
+func substituteExpr(e bf.Expr, substitutions map[string]string) bf.Expr {
+	switch e := e.(type) {
+	case *bf.StringExpr:
+		if rename, ok := substitutions[strings.TrimPrefix(e.Value, ":")]; ok {
+			return &bf.StringExpr{Value: ":" + rename}
+		}
+	case *bf.ListExpr:
+		var listCopy *bf.ListExpr
+		for i, elem := range e.List {
+			renamed := substituteExpr(elem, substitutions)
+			if renamed != elem {
+				if listCopy == nil {
+					listCopy = new(bf.ListExpr)
+					*listCopy = *e
+					listCopy.List = append([]bf.Expr{}, e.List...)
+				}
+				listCopy.List[i] = renamed
+			}
+		}
+		if listCopy != nil {
+			return listCopy
+		}
+	}
+	return e
+}
+
+// shouldKeep returns whether an expression from the original file should be
+// preserved. This is true if it has a prefix or end-of-line comment "keep".
+// Note that bf.Rewrite recognizes "keep sorted" comments which are different,
+// so we don't recognize comments that only start with "keep".
+func shouldKeep(e bf.Expr) bool {
+	for _, c := range append(e.Comment().Before, e.Comment().Suffix...) {
+		text := strings.TrimSpace(strings.TrimPrefix(c.Token, "#"))
+		if text == keep {
+			return true
+		}
+	}
+	return false
+}
+
+// matchAttrs contains lists of attributes for each kind that are used in
+// matching. For example, importpath attributes can be used to match go_library
+// rules, even when the names are different.
+var matchAttrs = map[string][]string{
+	"go_library":       {"importpath"},
+	"go_proto_library": {"importpath"},
+	"go_repository":    {"importpath"},
+}
+
+// matchAny is a set of kinds which may be matched regardless of attributes.
+// For example, if there is only one go_binary in a package, any go_binary
+// rule will match.
+var matchAny = map[string]bool{"go_binary": true}
+
+// match searches for a rule that can be merged with x in stmts.
+//
+// A rule is considered a match if its kind is equal to x's kind AND either its
+// name is equal OR at least one of the attributes in matchAttrs is equal.
+//
+// If there are no matches, nil, -1, and nil are returned.
+//
+// If a rule has the same name but a different kind, nil, -1, and an error
+// are returned.
+//
+// If there is exactly one match, the rule, its index in stmts, and nil
+// are returned.
+//
+// If there are multiple matches, match will attempt to disambiguate, based on
+// the quality of the match (name match is best, then attribute match in the
+// order that attributes are listed). If disambiguation is successful,
+// the rule, its index in stmts, and nil are returned. Otherwise, nil, -1,
+// and an error are returned.
+func match(stmts []bf.Expr, x *bf.CallExpr) (*bf.CallExpr, int, error) {
+	type matchInfo struct {
+		rule  bf.Rule
+		index int
+	}
+
+	xr := bf.Rule{Call: x}
+	xname := xr.Name()
+	xkind := xr.Kind()
+	var nameMatches []matchInfo
+	var kindMatches []matchInfo
+	for i, s := range stmts {
+		y, ok := s.(*bf.CallExpr)
+		if !ok {
+			continue
+		}
+		yr := bf.Rule{Call: y}
+		if xname == yr.Name() {
+			nameMatches = append(nameMatches, matchInfo{yr, i})
+		}
+		if xkind == yr.Kind() {
+			kindMatches = append(kindMatches, matchInfo{yr, i})
+		}
+	}
+
+	if len(nameMatches) == 1 {
+		if ykind := nameMatches[0].rule.Kind(); xkind != ykind {
+			return nil, -1, fmt.Errorf("could not merge %s(%s): a rule of the same name has kind %s", xkind, xname, ykind)
+		}
+		return nameMatches[0].rule.Call, nameMatches[0].index, nil
+	}
+	if len(nameMatches) > 1 {
+		return nil, -1, fmt.Errorf("could not merge %s(%s): multiple rules have the same name", xname)
+	}
+
+	attrs := matchAttrs[xr.Kind()]
+	for _, key := range attrs {
+		var attrMatches []matchInfo
+		xvalue := xr.AttrString(key)
+		if xvalue == "" {
+			continue
+		}
+		for _, m := range kindMatches {
+			if xvalue == m.rule.AttrString(key) {
+				attrMatches = append(attrMatches, m)
+			}
+		}
+		if len(attrMatches) == 1 {
+			return attrMatches[0].rule.Call, attrMatches[0].index, nil
+		} else if len(attrMatches) > 1 {
+			return nil, -1, fmt.Errorf("could not merge %s(%s): multiple rules have the same attribute %s = %q", xkind, xname, key, xvalue)
+		}
+	}
+
+	if matchAny[xkind] {
+		if len(kindMatches) == 1 {
+			return kindMatches[0].rule.Call, kindMatches[0].index, nil
+		} else if len(kindMatches) > 1 {
+			return nil, -1, fmt.Errorf("could not merge %s(%s): multiple rules have the same kind but different names", xkind, xname)
+		}
+	}
+
+	return nil, -1, nil
+}
+
+func kind(c *bf.CallExpr) string {
+	return (&bf.Rule{Call: c}).Kind()
+}
+
+func name(c *bf.CallExpr) string {
+	return (&bf.Rule{Call: c}).Name()
+}
+
+// isRuleEmpty returns true if a rule cannot be built because it has no sources,
+// dependencies, or embeds after merging. This is based on a per-kind whitelist
+// of attributes. Other attributes, like "name" and "visibility" don't affect
+// emptiness. Always returns false for expressions that aren't in the known
+// set of rules.
+func isRuleEmpty(e bf.Expr) bool {
+	c, ok := e.(*bf.CallExpr)
+	if !ok {
+		return false
+	}
+	r := bf.Rule{Call: c}
+	kind := r.Kind()
+	if nonEmptyAttrs[kind] == nil {
+		return false
+	}
+	for _, attr := range r.AttrKeys() {
+		if nonEmptyAttrs[kind][attr] {
+			return false
+		}
+	}
+	return true
+}
+
+func isScalar(e bf.Expr) bool {
+	switch e.(type) {
+	case *bf.StringExpr, *bf.LiteralExpr:
+		return true
+	default:
+		return false
+	}
+}
+
+func stringValue(e bf.Expr) string {
+	s, ok := e.(*bf.StringExpr)
+	if !ok {
+		return ""
+	}
+	return s.Value
+}
+
+// deleteIndices copies a list, dropping elements at deletedIndices.
+// deletedIndices must be sorted.
+func deleteIndices(stmt []bf.Expr, deletedIndices []int) []bf.Expr {
+	kept := make([]bf.Expr, 0, len(stmt)-len(deletedIndices))
+	di := 0
+	for i, s := range stmt {
+		if di < len(deletedIndices) && i == deletedIndices[di] {
+			di++
+			continue
+		}
+		kept = append(kept, s)
+	}
+	return kept
+}

vendor/github.com/bazelbuild/bazel-gazelle/internal/packages/BUILD

@@ -0,0 +1,34 @@
+load("@io_bazel_rules_go//go:def.bzl", "go_library")
+
+go_library(
+    name = "go_default_library",
+    srcs = [
+        "doc.go",
+        "fileinfo.go",
+        "fileinfo_go.go",
+        "fileinfo_proto.go",
+        "package.go",
+        "walk.go",
+    ],
+    importpath = "github.com/bazelbuild/bazel-gazelle/internal/packages",
+    visibility = ["//vendor/github.com/bazelbuild/bazel-gazelle:__subpackages__"],
+    deps = [
+        "//vendor/github.com/bazelbuild/bazel-gazelle/internal/config:go_default_library",
+        "//vendor/github.com/bazelbuild/bazel-gazelle/internal/pathtools:go_default_library",
+        "//vendor/github.com/bazelbuild/buildtools/build:go_default_library",
+    ],
+)
+
+filegroup(
+    name = "package-srcs",
+    srcs = glob(["**"]),
+    tags = ["automanaged"],
+    visibility = ["//visibility:private"],
+)
+
+filegroup(
+    name = "all-srcs",
+    srcs = [":package-srcs"],
+    tags = ["automanaged"],
+    visibility = ["//visibility:public"],
+)

vendor/github.com/bazelbuild/bazel-gazelle/internal/packages/doc.go

@@ -0,0 +1,17 @@
+/* Copyright 2016 The Bazel Authors. All rights reserved.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+   http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+// Package packages provides Go package traversal in a Bazel repository.
+package packages

vendor/github.com/bazelbuild/bazel-gazelle/internal/packages/fileinfo.go

@@ -0,0 +1,403 @@
+/* Copyright 2017 The Bazel Authors. All rights reserved.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+   http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package packages
+
+import (
+	"bufio"
+	"log"
+	"os"
+	"path"
+	"path/filepath"
+	"strings"
+
+	"github.com/bazelbuild/bazel-gazelle/internal/config"
+)
+
+// fileInfo holds information used to decide how to build a file. This
+// information comes from the file's name, from package and import declarations
+// (in .go files), and from +build and cgo comments.
+type fileInfo struct {
+	path, rel, name, ext string
+
+	// packageName is the Go package name of a .go file, without the
+	// "_test" suffix if it was present. It is empty for non-Go files.
+	packageName string
+
+	// importPath is the canonical import path for this file's package.
+	// This may be read from a package comment (in Go) or a go_package
+	// option (in proto). This field is empty for files that don't specify
+	// an import path.
+	importPath string
+
+	// category is the type of file, based on extension.
+	category extCategory
+
+	// isTest is true if the file stem (the part before the extension)
+	// ends with "_test.go". This is never true for non-Go files.
+	isTest bool
+
+	// isXTest is true for test Go files whose declared package name ends
+	// with "_test".
+	isXTest bool
+
+	// imports is a list of packages imported by a file. It does not include
+	// "C" or anything from the standard library.
+	imports []string
+
+	// isCgo is true for .go files that import "C".
+	isCgo bool
+
+	// goos and goarch contain the OS and architecture suffixes in the filename,
+	// if they were present.
+	goos, goarch string
+
+	// tags is a list of build tag lines. Each entry is the trimmed text of
+	// a line after a "+build" prefix.
+	tags []tagLine
+
+	// copts and clinkopts contain flags that are part of CFLAGS, CPPFLAGS,
+	// CXXFLAGS, and LDFLAGS directives in cgo comments.
+	copts, clinkopts []taggedOpts
+
+	// hasServices indicates whether a .proto file has service definitions.
+	hasServices bool
+}
+
+// tagLine represents the space-separated disjunction of build tag groups
+// in a line comment.
+type tagLine []tagGroup
+
+// check returns true if at least one of the tag groups is satisfied.
+func (l tagLine) check(c *config.Config, os, arch string) bool {
+	if len(l) == 0 {
+		return false
+	}
+	for _, g := range l {
+		if g.check(c, os, arch) {
+			return true
+		}
+	}
+	return false
+}
+
+// tagGroup represents a comma-separated conjuction of build tags.
+type tagGroup []string
+
+// check returns true if all of the tags are true. Tags that start with
+// "!" are negated (but "!!") is not allowed. Go release tags (e.g., "go1.8")
+// are ignored. If the group contains an os or arch tag, but the os or arch
+// parameters are empty, check returns false even if the tag is negated.
+func (g tagGroup) check(c *config.Config, os, arch string) bool {
+	for _, t := range g {
+		if strings.HasPrefix(t, "!!") { // bad syntax, reject always
+			return false
+		}
+		not := strings.HasPrefix(t, "!")
+		if not {
+			t = t[1:]
+		}
+		if isIgnoredTag(t) {
+			// Release tags are treated as "unknown" and are considered true,
+			// whether or not they are negated.
+			continue
+		}
+		var match bool
+		if _, ok := config.KnownOSSet[t]; ok {
+			if os == "" {
+				return false
+			}
+			match = os == t
+		} else if _, ok := config.KnownArchSet[t]; ok {
+			if arch == "" {
+				return false
+			}
+			match = arch == t
+		} else {
+			match = c.GenericTags[t]
+		}
+		if not {
+			match = !match
+		}
+		if !match {
+			return false
+		}
+	}
+	return true
+}
+
+// taggedOpts a list of compile or link options which should only be applied
+// if the given set of build tags are satisfied. These options have already
+// been tokenized using the same algorithm that "go build" uses, then joined
+// with OptSeparator.
+type taggedOpts struct {
+	tags tagLine
+	opts string
+}
+
+// OptSeparator is a special character inserted between options that appeared
+// together in a #cgo directive. This allows options to be split, modified,
+// and escaped by other packages.
+//
+// It's important to keep options grouped together in the same string. For
+// example, if we have "-framework IOKit" together in a #cgo directive,
+// "-framework" shouldn't be treated as a separate string for the purposes of
+// sorting and de-duplicating.
+const OptSeparator = "\x1D"
+
+// extCategory indicates how a file should be treated, based on extension.
+type extCategory int
+
+const (
+	// ignoredExt is applied to files which are not part of a build.
+	ignoredExt extCategory = iota
+
+	// unsupportedExt is applied to files that we don't support but would be
+	// built with "go build".
+	unsupportedExt
+
+	// goExt is applied to .go files.
+	goExt
+
+	// cExt is applied to C and C++ files.
+	cExt
+
+	// hExt is applied to header files. If cgo code is present, these may be
+	// C or C++ headers. If not, they are treated as Go assembly headers.
+	hExt
+
+	// sExt is applied to Go assembly files, ending with .s.
+	sExt
+
+	// csExt is applied to other assembly files, ending with .S. These are built
+	// with the C compiler if cgo code is present.
+	csExt
+
+	// protoExt is applied to .proto files.
+	protoExt
+)
+
+// fileNameInfo returns information that can be inferred from the name of
+// a file. It does not read data from the file.
+func fileNameInfo(dir, rel, name string) fileInfo {
+	ext := path.Ext(name)
+
+	// Categorize the file based on extension. Based on go/build.Context.Import.
+	var category extCategory
+	switch ext {
+	case ".go":
+		category = goExt
+	case ".c", ".cc", ".cpp", ".cxx":
+		category = cExt
+	case ".h", ".hh", ".hpp", ".hxx":
+		category = hExt
+	case ".s":
+		category = sExt
+	case ".S":
+		category = csExt
+	case ".proto":
+		category = protoExt
+	case ".m", ".f", ".F", ".for", ".f90", ".swig", ".swigcxx", ".syso":
+		category = unsupportedExt
+	default:
+		category = ignoredExt
+	}
+
+	// Determine test, goos, and goarch. This is intended to match the logic
+	// in goodOSArchFile in go/build.
+	var isTest bool
+	var goos, goarch string
+	l := strings.Split(name[:len(name)-len(ext)], "_")
+	if len(l) >= 2 && l[len(l)-1] == "test" {
+		isTest = category == goExt
+		l = l[:len(l)-1]
+	}
+	switch {
+	case len(l) >= 3 && config.KnownOSSet[l[len(l)-2]] && config.KnownArchSet[l[len(l)-1]]:
+		goos = l[len(l)-2]
+		goarch = l[len(l)-1]
+	case len(l) >= 2 && config.KnownOSSet[l[len(l)-1]]:
+		goos = l[len(l)-1]
+	case len(l) >= 2 && config.KnownArchSet[l[len(l)-1]]:
+		goarch = l[len(l)-1]
+	}
+
+	return fileInfo{
+		path:     filepath.Join(dir, name),
+		rel:      rel,
+		name:     name,
+		ext:      ext,
+		category: category,
+		isTest:   isTest,
+		goos:     goos,
+		goarch:   goarch,
+	}
+}
+
+// otherFileInfo returns information about a non-.go file. It will parse
+// part of the file to determine build tags. If the file can't be read, an
+// error will be logged, and partial information will be returned.
+func otherFileInfo(dir, rel, name string) fileInfo {
+	info := fileNameInfo(dir, rel, name)
+	if info.category == ignoredExt {
+		return info
+	}
+	if info.category == unsupportedExt {
+		log.Printf("%s: warning: file extension not yet supported", info.path)
+		return info
+	}
+
+	tags, err := readTags(info.path)
+	if err != nil {
+		log.Printf("%s: error reading file: %v", info.path, err)
+		return info
+	}
+	info.tags = tags
+	return info
+}
+
+// readTags reads and extracts build tags from the block of comments
+// and blank lines at the start of a file which is separated from the
+// rest of the file by a blank line. Each string in the returned slice
+// is the trimmed text of a line after a "+build" prefix.
+// Based on go/build.Context.shouldBuild.
+func readTags(path string) ([]tagLine, error) {
+	f, err := os.Open(path)
+	if err != nil {
+		return nil, err
+	}
+	defer f.Close()
+	scanner := bufio.NewScanner(f)
+
+	// Pass 1: Identify leading run of // comments and blank lines,
+	// which must be followed by a blank line.
+	var lines []string
+	end := 0
+	for scanner.Scan() {
+		line := strings.TrimSpace(scanner.Text())
+		if line == "" {
+			end = len(lines)
+			continue
+		}
+		if strings.HasPrefix(line, "//") {
+			lines = append(lines, line[len("//"):])
+			continue
+		}
+		break
+	}
+	if err := scanner.Err(); err != nil {
+		return nil, err
+	}
+	lines = lines[:end]
+
+	// Pass 2: Process each line in the run.
+	var tagLines []tagLine
+	for _, line := range lines {
+		fields := strings.Fields(line)
+		if len(fields) > 0 && fields[0] == "+build" {
+			tagLines = append(tagLines, parseTagsInGroups(fields[1:]))
+		}
+	}
+	return tagLines, nil
+}
+
+func parseTagsInGroups(groups []string) tagLine {
+	var l tagLine
+	for _, g := range groups {
+		l = append(l, tagGroup(strings.Split(g, ",")))
+	}
+	return l
+}
+
+func isOSArchSpecific(info fileInfo, cgoTags tagLine) (osSpecific, archSpecific bool) {
+	if info.goos != "" {
+		osSpecific = true
+	}
+	if info.goarch != "" {
+		archSpecific = true
+	}
+	lines := info.tags
+	if len(cgoTags) > 0 {
+		lines = append(lines, cgoTags)
+	}
+	for _, line := range lines {
+		for _, group := range line {
+			for _, tag := range group {
+				if strings.HasPrefix(tag, "!") {
+					tag = tag[1:]
+				}
+				_, osOk := config.KnownOSSet[tag]
+				if osOk {
+					osSpecific = true
+				}
+				_, archOk := config.KnownArchSet[tag]
+				if archOk {
+					archSpecific = true
+				}
+			}
+		}
+	}
+	return osSpecific, archSpecific
+}
+
+// checkConstraints determines whether build constraints are satisfied on
+// a given platform.
+//
+// The first few arguments describe the platform. genericTags is the set
+// of build tags that are true on all platforms. os and arch are the platform
+// GOOS and GOARCH strings. If os or arch is empty, checkConstraints will
+// return false in the presence of OS and architecture constraints, even
+// if they are negated.
+//
+// The remaining arguments describe the file being tested. All of these may
+// be empty or nil. osSuffix and archSuffix are filename suffixes. fileTags
+// is a list tags from +build comments found near the top of the file. cgoTags
+// is an extra set of tags in a #cgo directive.
+func checkConstraints(c *config.Config, os, arch, osSuffix, archSuffix string, fileTags []tagLine, cgoTags tagLine) bool {
+	if osSuffix != "" && osSuffix != os || archSuffix != "" && archSuffix != arch {
+		return false
+	}
+	for _, l := range fileTags {
+		if !l.check(c, os, arch) {
+			return false
+		}
+	}
+	if len(cgoTags) > 0 && !cgoTags.check(c, os, arch) {
+		return false
+	}
+	return true
+}
+
+// isIgnoredTag returns whether the tag is "cgo" or is a release tag.
+// Release tags match the pattern "go[0-9]\.[0-9]+".
+// Gazelle won't consider whether an ignored tag is satisfied when evaluating
+// build constraints for a file.
+func isIgnoredTag(tag string) bool {
+	if tag == "cgo" {
+		return true
+	}
+	if len(tag) < 5 || !strings.HasPrefix(tag, "go") {
+		return false
+	}
+	if tag[2] < '0' || tag[2] > '9' || tag[3] != '.' {
+		return false
+	}
+	for _, c := range tag[4:] {
+		if c < '0' || c > '9' {
+			return false
+		}
+	}
+	return true
+}

vendor/github.com/bazelbuild/bazel-gazelle/internal/packages/fileinfo_go.go

@@ -0,0 +1,275 @@
+/* Copyright 2017 The Bazel Authors. All rights reserved.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+   http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package packages
+
+import (
+	"bytes"
+	"errors"
+	"fmt"
+	"go/ast"
+	"go/parser"
+	"go/token"
+	"log"
+	"path/filepath"
+	"strconv"
+	"strings"
+	"unicode"
+	"unicode/utf8"
+
+	"github.com/bazelbuild/bazel-gazelle/internal/config"
+)
+
+// goFileInfo returns information about a .go file. It will parse part of the
+// file to determine the package name, imports, and build constraints.
+// If the file can't be read, an error will be logged, and partial information
+// will be returned.
+// This function is intended to match go/build.Context.Import.
+// TODD(#53): extract canonical import path
+func goFileInfo(c *config.Config, dir, rel, name string) fileInfo {
+	info := fileNameInfo(dir, rel, name)
+	fset := token.NewFileSet()
+	pf, err := parser.ParseFile(fset, info.path, nil, parser.ImportsOnly|parser.ParseComments)
+	if err != nil {
+		log.Printf("%s: error reading go file: %v", info.path, err)
+		return info
+	}
+
+	info.packageName = pf.Name.Name
+	if info.isTest && strings.HasSuffix(info.packageName, "_test") {
+		info.isXTest = true
+		info.packageName = info.packageName[:len(info.packageName)-len("_test")]
+	}
+
+	for _, decl := range pf.Decls {
+		d, ok := decl.(*ast.GenDecl)
+		if !ok {
+			continue
+		}
+		for _, dspec := range d.Specs {
+			spec, ok := dspec.(*ast.ImportSpec)
+			if !ok {
+				continue
+			}
+			quoted := spec.Path.Value
+			path, err := strconv.Unquote(quoted)
+			if err != nil {
+				log.Printf("%s: error reading go file: %v", info.path, err)
+				continue
+			}
+
+			if path == "C" {
+				if info.isTest {
+					log.Printf("%s: warning: use of cgo in test not supported", info.path)
+				}
+				info.isCgo = true
+				cg := spec.Doc
+				if cg == nil && len(d.Specs) == 1 {
+					cg = d.Doc
+				}
+				if cg != nil {
+					if err := saveCgo(&info, cg); err != nil {
+						log.Printf("%s: error reading go file: %v", info.path, err)
+					}
+				}
+				continue
+			}
+			info.imports = append(info.imports, path)
+		}
+	}
+
+	tags, err := readTags(info.path)
+	if err != nil {
+		log.Printf("%s: error reading go file: %v", info.path, err)
+		return info
+	}
+	info.tags = tags
+
+	return info
+}
+
+// saveCgo extracts CFLAGS, CPPFLAGS, CXXFLAGS, and LDFLAGS directives
+// from a comment above a "C" import. This is intended to match logic in
+// go/build.Context.saveCgo.
+func saveCgo(info *fileInfo, cg *ast.CommentGroup) error {
+	text := cg.Text()
+	for _, line := range strings.Split(text, "\n") {
+		orig := line
+
+		// Line is
+		//	#cgo [GOOS/GOARCH...] LDFLAGS: stuff
+		//
+		line = strings.TrimSpace(line)
+		if len(line) < 5 || line[:4] != "#cgo" || (line[4] != ' ' && line[4] != '\t') {
+			continue
+		}
+
+		// Split at colon.
+		line = strings.TrimSpace(line[4:])
+		i := strings.Index(line, ":")
+		if i < 0 {
+			return fmt.Errorf("%s: invalid #cgo line: %s", info.path, orig)
+		}
+		line, optstr := strings.TrimSpace(line[:i]), strings.TrimSpace(line[i+1:])
+
+		// Parse tags and verb.
+		f := strings.Fields(line)
+		if len(f) < 1 {
+			return fmt.Errorf("%s: invalid #cgo line: %s", info.path, orig)
+		}
+		verb := f[len(f)-1]
+		tags := parseTagsInGroups(f[:len(f)-1])
+
+		// Parse options.
+		opts, err := splitQuoted(optstr)
+		if err != nil {
+			return fmt.Errorf("%s: invalid #cgo line: %s", info.path, orig)
+		}
+		var ok bool
+		for i, opt := range opts {
+			if opt, ok = expandSrcDir(opt, info.rel); !ok {
+				return fmt.Errorf("%s: malformed #cgo argument: %s", info.path, orig)
+			}
+			opts[i] = opt
+		}
+		joinedStr := strings.Join(opts, OptSeparator)
+
+		// Add tags to appropriate list.
+		switch verb {
+		case "CFLAGS", "CPPFLAGS", "CXXFLAGS":
+			info.copts = append(info.copts, taggedOpts{tags, joinedStr})
+		case "LDFLAGS":
+			info.clinkopts = append(info.clinkopts, taggedOpts{tags, joinedStr})
+		case "pkg-config":
+			return fmt.Errorf("%s: pkg-config not supported: %s", info.path, orig)
+		default:
+			return fmt.Errorf("%s: invalid #cgo verb: %s", info.path, orig)
+		}
+	}
+	return nil
+}
+
+// splitQuoted splits the string s around each instance of one or more consecutive
+// white space characters while taking into account quotes and escaping, and
+// returns an array of substrings of s or an empty list if s contains only white space.
+// Single quotes and double quotes are recognized to prevent splitting within the
+// quoted region, and are removed from the resulting substrings. If a quote in s
+// isn't closed err will be set and r will have the unclosed argument as the
+// last element. The backslash is used for escaping.
+//
+// For example, the following string:
+//
+//     a b:"c d" 'e''f'  "g\""
+//
+// Would be parsed as:
+//
+//     []string{"a", "b:c d", "ef", `g"`}
+//
+// Copied from go/build.splitQuoted
+func splitQuoted(s string) (r []string, err error) {
+	var args []string
+	arg := make([]rune, len(s))
+	escaped := false
+	quoted := false
+	quote := '\x00'
+	i := 0
+	for _, rune := range s {
+		switch {
+		case escaped:
+			escaped = false
+		case rune == '\\':
+			escaped = true
+			continue
+		case quote != '\x00':
+			if rune == quote {
+				quote = '\x00'
+				continue
+			}
+		case rune == '"' || rune == '\'':
+			quoted = true
+			quote = rune
+			continue
+		case unicode.IsSpace(rune):
+			if quoted || i > 0 {
+				quoted = false
+				args = append(args, string(arg[:i]))
+				i = 0
+			}
+			continue
+		}
+		arg[i] = rune
+		i++
+	}
+	if quoted || i > 0 {
+		args = append(args, string(arg[:i]))
+	}
+	if quote != 0 {
+		err = errors.New("unclosed quote")
+	} else if escaped {
+		err = errors.New("unfinished escaping")
+	}
+	return args, err
+}
+
+// expandSrcDir expands any occurrence of ${SRCDIR}, making sure
+// the result is safe for the shell.
+//
+// Copied from go/build.expandSrcDir
+func expandSrcDir(str string, srcdir string) (string, bool) {
+	// "\" delimited paths cause safeCgoName to fail
+	// so convert native paths with a different delimiter
+	// to "/" before starting (eg: on windows).
+	srcdir = filepath.ToSlash(srcdir)
+
+	// Spaces are tolerated in ${SRCDIR}, but not anywhere else.
+	chunks := strings.Split(str, "${SRCDIR}")
+	if len(chunks) < 2 {
+		return str, safeCgoName(str, false)
+	}
+	ok := true
+	for _, chunk := range chunks {
+		ok = ok && (chunk == "" || safeCgoName(chunk, false))
+	}
+	ok = ok && (srcdir == "" || safeCgoName(srcdir, true))
+	res := strings.Join(chunks, srcdir)
+	return res, ok && res != ""
+}
+
+// NOTE: $ is not safe for the shell, but it is allowed here because of linker options like -Wl,$ORIGIN.
+// We never pass these arguments to a shell (just to programs we construct argv for), so this should be okay.
+// See golang.org/issue/6038.
+// The @ is for OS X. See golang.org/issue/13720.
+// The % is for Jenkins. See golang.org/issue/16959.
+const safeString = "+-.,/0123456789=ABCDEFGHIJKLMNOPQRSTUVWXYZ_abcdefghijklmnopqrstuvwxyz:$@%"
+const safeSpaces = " "
+
+var safeBytes = []byte(safeSpaces + safeString)
+
+// Copied from go/build.safeCgoName
+func safeCgoName(s string, spaces bool) bool {
+	if s == "" {
+		return false
+	}
+	safe := safeBytes
+	if !spaces {
+		safe = safe[len(safeSpaces):]
+	}
+	for i := 0; i < len(s); i++ {
+		if c := s[i]; c < utf8.RuneSelf && bytes.IndexByte(safe, c) < 0 {
+			return false
+		}
+	}
+	return true
+}

vendor/github.com/bazelbuild/bazel-gazelle/internal/packages/fileinfo_proto.go

@@ -0,0 +1,138 @@
+/* Copyright 2017 The Bazel Authors. All rights reserved.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+   http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package packages
+
+import (
+	"bytes"
+	"io/ioutil"
+	"log"
+	"path"
+	"regexp"
+	"sort"
+	"strconv"
+	"strings"
+	"unicode"
+
+	"github.com/bazelbuild/bazel-gazelle/internal/config"
+)
+
+var protoRe = buildProtoRegexp()
+
+const (
+	importSubexpIndex    = 1
+	packageSubexpIndex   = 2
+	goPackageSubexpIndex = 3
+	serviceSubexpIndex   = 4
+)
+
+func protoFileInfo(c *config.Config, dir, rel, name string) fileInfo {
+	info := fileNameInfo(dir, rel, name)
+	content, err := ioutil.ReadFile(info.path)
+	if err != nil {
+		log.Printf("%s: error reading proto file: %v", info.path, err)
+		return info
+	}
+
+	for _, match := range protoRe.FindAllSubmatch(content, -1) {
+		switch {
+		case match[importSubexpIndex] != nil:
+			imp := unquoteProtoString(match[importSubexpIndex])
+			info.imports = append(info.imports, imp)
+
+		case match[packageSubexpIndex] != nil:
+			pkg := string(match[packageSubexpIndex])
+			if info.packageName == "" {
+				info.packageName = strings.Replace(pkg, ".", "_", -1)
+			}
+
+		case match[goPackageSubexpIndex] != nil:
+			gopkg := unquoteProtoString(match[goPackageSubexpIndex])
+			// If there's no / in the package option, then it's just a
+			// simple package name, not a full import path.
+			if strings.LastIndexByte(gopkg, '/') == -1 {
+				info.packageName = gopkg
+			} else {
+				if i := strings.LastIndexByte(gopkg, ';'); i != -1 {
+					info.importPath = gopkg[:i]
+					info.packageName = gopkg[i+1:]
+				} else {
+					info.importPath = gopkg
+					info.packageName = path.Base(gopkg)
+				}
+			}
+
+		case match[serviceSubexpIndex] != nil:
+			info.hasServices = true
+
+		default:
+			// Comment matched. Nothing to extract.
+		}
+	}
+	sort.Strings(info.imports)
+
+	if info.packageName == "" {
+		stem := strings.TrimSuffix(name, ".proto")
+		fs := strings.FieldsFunc(stem, func(r rune) bool {
+			return !(unicode.IsLetter(r) || unicode.IsNumber(r) || r == '_')
+		})
+		info.packageName = strings.Join(fs, "_")
+	}
+
+	return info
+}
+
+// Based on https://developers.google.com/protocol-buffers/docs/reference/proto3-spec
+func buildProtoRegexp() *regexp.Regexp {
+	hexEscape := `\\[xX][0-9a-fA-f]{2}`
+	octEscape := `\\[0-7]{3}`
+	charEscape := `\\[abfnrtv'"\\]`
+	charValue := strings.Join([]string{hexEscape, octEscape, charEscape, "[^\x00\\'\\\"\\\\]"}, "|")
+	strLit := `'(?:` + charValue + `|")*'|"(?:` + charValue + `|')*"`
+	ident := `[A-Za-z][A-Za-z0-9_]*`
+	fullIdent := ident + `(?:\.` + ident + `)*`
+	importStmt := `\bimport\s*(?:public|weak)?\s*(?P<import>` + strLit + `)\s*;`
+	packageStmt := `\bpackage\s*(?P<package>` + fullIdent + `)\s*;`
+	goPackageStmt := `\boption\s*go_package\s*=\s*(?P<go_package>` + strLit + `)\s*;`
+	serviceStmt := `(?P<service>service)`
+	comment := `//[^\n]*`
+	protoReSrc := strings.Join([]string{importStmt, packageStmt, goPackageStmt, serviceStmt, comment}, "|")
+	return regexp.MustCompile(protoReSrc)
+}
+
+func unquoteProtoString(q []byte) string {
+	// Adjust quotes so that Unquote is happy. We need a double quoted string
+	// without unescaped double quote characters inside.
+	noQuotes := bytes.Split(q[1:len(q)-1], []byte{'"'})
+	if len(noQuotes) != 1 {
+		for i := 0; i < len(noQuotes)-1; i++ {
+			if len(noQuotes[i]) == 0 || noQuotes[i][len(noQuotes[i])-1] != '\\' {
+				noQuotes[i] = append(noQuotes[i], '\\')
+			}
+		}
+		q = append([]byte{'"'}, bytes.Join(noQuotes, []byte{'"'})...)
+		q = append(q, '"')
+	}
+	if q[0] == '\'' {
+		q[0] = '"'
+		q[len(q)-1] = '"'
+	}
+
+	s, err := strconv.Unquote(string(q))
+	if err != nil {
+		log.Panicf("unquoting string literal %s from proto: %v", q, err)
+	}
+	return s
+}

vendor/github.com/bazelbuild/bazel-gazelle/internal/packages/package.go

@@ -0,0 +1,630 @@
+/* Copyright 2017 The Bazel Authors. All rights reserved.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+   http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package packages
+
+import (
+	"fmt"
+	"log"
+	"path"
+	"sort"
+	"strings"
+
+	"github.com/bazelbuild/bazel-gazelle/internal/config"
+	"github.com/bazelbuild/bazel-gazelle/internal/pathtools"
+)
+
+// Package contains metadata about a Go package extracted from a directory.
+// It fills a similar role to go/build.Package, but it separates files by
+// target instead of by type, and it supports multiple platforms.
+type Package struct {
+	// Name is the symbol found in package declarations of the .go files in
+	// the package. It does not include the "_test" suffix from external tests.
+	Name string
+
+	// Dir is an absolute path to the directory that contains the package.
+	Dir string
+
+	// Rel is the relative path to the package directory from the repository
+	// root. If the directory is the repository root itself, Rel is empty.
+	// Components in Rel are separated with slashes.
+	Rel string
+
+	// ImportPath is the string used to import this package in Go.
+	ImportPath string
+
+	Library, Binary, Test, XTest GoTarget
+	Proto                        ProtoTarget
+
+	HasTestdata bool
+}
+
+// GoTarget contains metadata about a buildable Go target in a package.
+type GoTarget struct {
+	Sources, Imports PlatformStrings
+	COpts, CLinkOpts PlatformStrings
+	Cgo              bool
+}
+
+// ProtoTarget contains metadata about proto files in a package.
+type ProtoTarget struct {
+	Sources, Imports PlatformStrings
+	HasServices      bool
+
+	// HasPbGo indicates whether unexcluded .pb.go files are present in the
+	// same package. They will not be in this target's sources.
+	HasPbGo bool
+}
+
+// PlatformStrings contains a set of strings associated with a buildable
+// Go target in a package. This is used to store source file names,
+// import paths, and flags.
+//
+// Strings are stored in four sets: generic strings, OS-specific strings,
+// arch-specific strings, and OS-and-arch-specific strings. A string may not
+// be duplicated within a list or across sets; however, a string may appear
+// in more than one list within a set (e.g., in "linux" and "windows" within
+// the OS set). Strings within each list should be sorted, though this may
+// not be relied upon.
+type PlatformStrings struct {
+	// Generic is a list of strings not specific to any platform.
+	Generic []string
+
+	// OS is a map from OS name (anything in config.KnownOSs) to
+	// OS-specific strings.
+	OS map[string][]string
+
+	// Arch is a map from architecture name (anything in config.KnownArchs) to
+	// architecture-specific strings.
+	Arch map[string][]string
+
+	// Platform is a map from platforms to OS and architecture-specific strings.
+	Platform map[config.Platform][]string
+}
+
+// IsCommand returns true if the package name is "main".
+func (p *Package) IsCommand() bool {
+	return p.Name == "main"
+}
+
+// EmptyPackage returns an empty package. The package name and import path
+// are inferred from the directory name and configuration. This is useful
+// for deleting rules in directories which no longer have source files.
+func EmptyPackage(c *config.Config, dir, rel string) *Package {
+	packageName := pathtools.RelBaseName(rel, c.GoPrefix, c.RepoRoot)
+	pb := packageBuilder{
+		name: packageName,
+		dir:  dir,
+		rel:  rel,
+	}
+	pb.inferImportPath(c)
+	return pb.build()
+}
+
+func (t *GoTarget) HasGo() bool {
+	return t.Sources.HasGo()
+}
+
+func (t *ProtoTarget) HasProto() bool {
+	return !t.Sources.IsEmpty()
+}
+
+func (ps *PlatformStrings) HasGo() bool {
+	return ps.firstGoFile() != ""
+}
+
+func (ps *PlatformStrings) IsEmpty() bool {
+	return len(ps.Generic) == 0 && len(ps.OS) == 0 && len(ps.Arch) == 0 && len(ps.Platform) == 0
+}
+
+func (ps *PlatformStrings) firstGoFile() string {
+	for _, f := range ps.Generic {
+		if strings.HasSuffix(f, ".go") {
+			return f
+		}
+	}
+	for _, fs := range ps.OS {
+		for _, f := range fs {
+			if strings.HasSuffix(f, ".go") {
+				return f
+			}
+		}
+	}
+	for _, fs := range ps.Arch {
+		for _, f := range fs {
+			if strings.HasSuffix(f, ".go") {
+				return f
+			}
+		}
+	}
+	for _, fs := range ps.Platform {
+		for _, f := range fs {
+			if strings.HasSuffix(f, ".go") {
+				return f
+			}
+		}
+	}
+	return ""
+}
+
+type packageBuilder struct {
+	name, dir, rel               string
+	library, binary, test, xtest goTargetBuilder
+	proto                        protoTargetBuilder
+	hasTestdata                  bool
+	importPath, importPathFile   string
+}
+
+type goTargetBuilder struct {
+	sources, imports, copts, clinkopts platformStringsBuilder
+	cgo                                bool
+}
+
+type protoTargetBuilder struct {
+	sources, imports     platformStringsBuilder
+	hasServices, hasPbGo bool
+}
+
+type platformStringsBuilder struct {
+	strs map[string]platformStringInfo
+}
+
+type platformStringInfo struct {
+	set       platformStringSet
+	oss       map[string]bool
+	archs     map[string]bool
+	platforms map[config.Platform]bool
+}
+
+type platformStringSet int
+
+const (
+	genericSet platformStringSet = iota
+	osSet
+	archSet
+	platformSet
+)
+
+// addFile adds the file described by "info" to a target in the package "p" if
+// the file is buildable.
+//
+// "cgo" tells whether any ".go" file in the package contains cgo code. This
+// affects whether C files are added to targets.
+//
+// An error is returned if a file is buildable but invalid (for example, a
+// test .go file containing cgo code). Files that are not buildable will not
+// be added to any target (for example, .txt files).
+func (pb *packageBuilder) addFile(c *config.Config, info fileInfo, cgo bool) error {
+	switch {
+	case info.category == ignoredExt || info.category == unsupportedExt ||
+		!cgo && (info.category == cExt || info.category == csExt) ||
+		c.ProtoMode == config.DisableProtoMode && info.category == protoExt:
+		return nil
+	case info.isXTest:
+		if info.isCgo {
+			return fmt.Errorf("%s: use of cgo in test not supported", info.path)
+		}
+		pb.xtest.addFile(c, info)
+	case info.isTest:
+		if info.isCgo {
+			return fmt.Errorf("%s: use of cgo in test not supported", info.path)
+		}
+		pb.test.addFile(c, info)
+	case info.category == protoExt:
+		pb.proto.addFile(c, info)
+	default:
+		pb.library.addFile(c, info)
+	}
+	if strings.HasSuffix(info.name, ".pb.go") {
+		pb.proto.hasPbGo = true
+	}
+
+	if info.importPath != "" {
+		if pb.importPath == "" {
+			pb.importPath = info.importPath
+			pb.importPathFile = info.path
+		} else if pb.importPath != info.importPath {
+			return fmt.Errorf("found import comments %q (%s) and %q (%s)", pb.importPath, pb.importPathFile, info.importPath, info.path)
+		}
+	}
+
+	return nil
+}
+
+// isBuildable returns true if anything in the package is buildable.
+// This is true if the package has Go code that satisfies build constraints
+// on any platform or has proto files not in legacy mode.
+func (pb *packageBuilder) isBuildable(c *config.Config) bool {
+	return pb.firstGoFile() != "" ||
+		len(pb.proto.sources.strs) > 0 && c.ProtoMode == config.DefaultProtoMode
+}
+
+// firstGoFile returns the name of a .go file if the package contains at least
+// one .go file, or "" otherwise.
+func (pb *packageBuilder) firstGoFile() string {
+	goSrcs := []platformStringsBuilder{
+		pb.library.sources,
+		pb.binary.sources,
+		pb.test.sources,
+		pb.xtest.sources,
+	}
+	for _, sb := range goSrcs {
+		if sb.strs != nil {
+			for s, _ := range sb.strs {
+				if strings.HasSuffix(s, ".go") {
+					return s
+				}
+			}
+		}
+	}
+	return ""
+}
+
+func (pb *packageBuilder) inferImportPath(c *config.Config) error {
+	if pb.importPath != "" {
+		log.Panic("importPath already set")
+	}
+	if pb.rel == c.GoPrefixRel {
+		if c.GoPrefix == "" {
+			return fmt.Errorf("in directory %q, prefix is empty, so importpath would be empty for rules. Set a prefix with a '# gazelle:prefix' comment or with -go_prefix on the command line.", pb.dir)
+		}
+		pb.importPath = c.GoPrefix
+	} else {
+		fromPrefixRel := strings.TrimPrefix(pb.rel, c.GoPrefixRel+"/")
+		pb.importPath = path.Join(c.GoPrefix, fromPrefixRel)
+	}
+	return nil
+}
+
+func (pb *packageBuilder) build() *Package {
+	return &Package{
+		Name:        pb.name,
+		Dir:         pb.dir,
+		Rel:         pb.rel,
+		ImportPath:  pb.importPath,
+		Library:     pb.library.build(),
+		Binary:      pb.binary.build(),
+		Test:        pb.test.build(),
+		XTest:       pb.xtest.build(),
+		Proto:       pb.proto.build(),
+		HasTestdata: pb.hasTestdata,
+	}
+}
+
+func (tb *goTargetBuilder) addFile(c *config.Config, info fileInfo) {
+	tb.cgo = tb.cgo || info.isCgo
+	add := getPlatformStringsAddFunction(c, info, nil)
+	add(&tb.sources, info.name)
+	add(&tb.imports, info.imports...)
+	for _, copts := range info.copts {
+		optAdd := add
+		if len(copts.tags) > 0 {
+			optAdd = getPlatformStringsAddFunction(c, info, copts.tags)
+		}
+		optAdd(&tb.copts, copts.opts)
+	}
+	for _, clinkopts := range info.clinkopts {
+		optAdd := add
+		if len(clinkopts.tags) > 0 {
+			optAdd = getPlatformStringsAddFunction(c, info, clinkopts.tags)
+		}
+		optAdd(&tb.clinkopts, clinkopts.opts)
+	}
+}
+
+func (tb *goTargetBuilder) build() GoTarget {
+	return GoTarget{
+		Sources:   tb.sources.build(),
+		Imports:   tb.imports.build(),
+		COpts:     tb.copts.build(),
+		CLinkOpts: tb.clinkopts.build(),
+		Cgo:       tb.cgo,
+	}
+}
+
+func (tb *protoTargetBuilder) addFile(c *config.Config, info fileInfo) {
+	add := getPlatformStringsAddFunction(c, info, nil)
+	add(&tb.sources, info.name)
+	add(&tb.imports, info.imports...)
+	tb.hasServices = tb.hasServices || info.hasServices
+}
+
+func (tb *protoTargetBuilder) build() ProtoTarget {
+	return ProtoTarget{
+		Sources:     tb.sources.build(),
+		Imports:     tb.imports.build(),
+		HasServices: tb.hasServices,
+		HasPbGo:     tb.hasPbGo,
+	}
+}
+
+// getPlatformStringsAddFunction returns a function used to add strings to
+// a *platformStringsBuilder under the same set of constraints. This is a
+// performance optimization to avoid evaluating constraints repeatedly.
+func getPlatformStringsAddFunction(c *config.Config, info fileInfo, cgoTags tagLine) func(sb *platformStringsBuilder, ss ...string) {
+	isOSSpecific, isArchSpecific := isOSArchSpecific(info, cgoTags)
+
+	switch {
+	case !isOSSpecific && !isArchSpecific:
+		if checkConstraints(c, "", "", info.goos, info.goarch, info.tags, cgoTags) {
+			return func(sb *platformStringsBuilder, ss ...string) {
+				for _, s := range ss {
+					sb.addGenericString(s)
+				}
+			}
+		}
+
+	case isOSSpecific && !isArchSpecific:
+		var osMatch []string
+		for _, os := range config.KnownOSs {
+			if checkConstraints(c, os, "", info.goos, info.goarch, info.tags, cgoTags) {
+				osMatch = append(osMatch, os)
+			}
+		}
+		if len(osMatch) > 0 {
+			return func(sb *platformStringsBuilder, ss ...string) {
+				for _, s := range ss {
+					sb.addOSString(s, osMatch)
+				}
+			}
+		}
+
+	case !isOSSpecific && isArchSpecific:
+		var archMatch []string
+		for _, arch := range config.KnownArchs {
+			if checkConstraints(c, "", arch, info.goos, info.goarch, info.tags, cgoTags) {
+				archMatch = append(archMatch, arch)
+			}
+		}
+		if len(archMatch) > 0 {
+			return func(sb *platformStringsBuilder, ss ...string) {
+				for _, s := range ss {
+					sb.addArchString(s, archMatch)
+				}
+			}
+		}
+
+	default:
+		var platformMatch []config.Platform
+		for _, platform := range config.KnownPlatforms {
+			if checkConstraints(c, platform.OS, platform.Arch, info.goos, info.goarch, info.tags, cgoTags) {
+				platformMatch = append(platformMatch, platform)
+			}
+		}
+		if len(platformMatch) > 0 {
+			return func(sb *platformStringsBuilder, ss ...string) {
+				for _, s := range ss {
+					sb.addPlatformString(s, platformMatch)
+				}
+			}
+		}
+	}
+
+	return func(_ *platformStringsBuilder, _ ...string) {}
+}
+
+func (sb *platformStringsBuilder) addGenericString(s string) {
+	if sb.strs == nil {
+		sb.strs = make(map[string]platformStringInfo)
+	}
+	sb.strs[s] = platformStringInfo{set: genericSet}
+}
+
+func (sb *platformStringsBuilder) addOSString(s string, oss []string) {
+	if sb.strs == nil {
+		sb.strs = make(map[string]platformStringInfo)
+	}
+	si, ok := sb.strs[s]
+	if !ok {
+		si.set = osSet
+		si.oss = make(map[string]bool)
+	}
+	switch si.set {
+	case genericSet:
+		return
+	case osSet:
+		for _, os := range oss {
+			si.oss[os] = true
+		}
+	default:
+		si.convertToPlatforms()
+		for _, os := range oss {
+			for _, arch := range config.KnownOSArchs[os] {
+				si.platforms[config.Platform{OS: os, Arch: arch}] = true
+			}
+		}
+	}
+	sb.strs[s] = si
+}
+
+func (sb *platformStringsBuilder) addArchString(s string, archs []string) {
+	if sb.strs == nil {
+		sb.strs = make(map[string]platformStringInfo)
+	}
+	si, ok := sb.strs[s]
+	if !ok {
+		si.set = archSet
+		si.archs = make(map[string]bool)
+	}
+	switch si.set {
+	case genericSet:
+		return
+	case archSet:
+		for _, arch := range archs {
+			si.archs[arch] = true
+		}
+	default:
+		si.convertToPlatforms()
+		for _, arch := range archs {
+			for _, os := range config.KnownArchOSs[arch] {
+				si.platforms[config.Platform{OS: os, Arch: arch}] = true
+			}
+		}
+	}
+	sb.strs[s] = si
+}
+
+func (sb *platformStringsBuilder) addPlatformString(s string, platforms []config.Platform) {
+	if sb.strs == nil {
+		sb.strs = make(map[string]platformStringInfo)
+	}
+	si, ok := sb.strs[s]
+	if !ok {
+		si.set = platformSet
+		si.platforms = make(map[config.Platform]bool)
+	}
+	switch si.set {
+	case genericSet:
+		return
+	default:
+		si.convertToPlatforms()
+		for _, p := range platforms {
+			si.platforms[p] = true
+		}
+	}
+	sb.strs[s] = si
+}
+
+func (sb *platformStringsBuilder) build() PlatformStrings {
+	var ps PlatformStrings
+	for s, si := range sb.strs {
+		switch si.set {
+		case genericSet:
+			ps.Generic = append(ps.Generic, s)
+		case osSet:
+			if ps.OS == nil {
+				ps.OS = make(map[string][]string)
+			}
+			for os, _ := range si.oss {
+				ps.OS[os] = append(ps.OS[os], s)
+			}
+		case archSet:
+			if ps.Arch == nil {
+				ps.Arch = make(map[string][]string)
+			}
+			for arch, _ := range si.archs {
+				ps.Arch[arch] = append(ps.Arch[arch], s)
+			}
+		case platformSet:
+			if ps.Platform == nil {
+				ps.Platform = make(map[config.Platform][]string)
+			}
+			for p, _ := range si.platforms {
+				ps.Platform[p] = append(ps.Platform[p], s)
+			}
+		}
+	}
+	sort.Strings(ps.Generic)
+	if ps.OS != nil {
+		for _, ss := range ps.OS {
+			sort.Strings(ss)
+		}
+	}
+	if ps.Arch != nil {
+		for _, ss := range ps.Arch {
+			sort.Strings(ss)
+		}
+	}
+	if ps.Platform != nil {
+		for _, ss := range ps.Platform {
+			sort.Strings(ss)
+		}
+	}
+	return ps
+}
+
+func (si *platformStringInfo) convertToPlatforms() {
+	switch si.set {
+	case genericSet:
+		log.Panic("cannot convert generic string to platforms")
+	case platformSet:
+		return
+	case osSet:
+		si.set = platformSet
+		si.platforms = make(map[config.Platform]bool)
+		for os, _ := range si.oss {
+			for _, arch := range config.KnownOSArchs[os] {
+				si.platforms[config.Platform{OS: os, Arch: arch}] = true
+			}
+		}
+		si.oss = nil
+	case archSet:
+		si.set = platformSet
+		si.platforms = make(map[config.Platform]bool)
+		for arch, _ := range si.archs {
+			for _, os := range config.KnownArchOSs[arch] {
+				si.platforms[config.Platform{OS: os, Arch: arch}] = true
+			}
+		}
+		si.archs = nil
+	}
+}
+
+// MapSlice applies a function that processes slices of strings to the strings
+// in "ps" and returns a new PlatformStrings with the results.
+func (ps *PlatformStrings) MapSlice(f func([]string) ([]string, error)) (PlatformStrings, []error) {
+	var errors []error
+
+	mapSlice := func(ss []string) []string {
+		rs, err := f(ss)
+		if err != nil {
+			errors = append(errors, err)
+			return nil
+		}
+		return rs
+	}
+
+	mapStringMap := func(m map[string][]string) map[string][]string {
+		if m == nil {
+			return nil
+		}
+		rm := make(map[string][]string)
+		for k, ss := range m {
+			ss = mapSlice(ss)
+			if len(ss) > 0 {
+				rm[k] = ss
+			}
+		}
+		if len(rm) == 0 {
+			return nil
+		}
+		return rm
+	}
+
+	mapPlatformMap := func(m map[config.Platform][]string) map[config.Platform][]string {
+		if m == nil {
+			return nil
+		}
+		rm := make(map[config.Platform][]string)
+		for k, ss := range m {
+			ss = mapSlice(ss)
+			if len(ss) > 0 {
+				rm[k] = ss
+			}
+		}
+		if len(rm) == 0 {
+			return nil
+		}
+		return rm
+	}
+
+	result := PlatformStrings{
+		Generic:  mapSlice(ps.Generic),
+		OS:       mapStringMap(ps.OS),
+		Arch:     mapStringMap(ps.Arch),
+		Platform: mapPlatformMap(ps.Platform),
+	}
+	return result, errors
+}

vendor/github.com/bazelbuild/bazel-gazelle/internal/packages/walk.go

@@ -0,0 +1,460 @@
+/* Copyright 2016 The Bazel Authors. All rights reserved.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+   http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package packages
+
+import (
+	"go/build"
+	"io/ioutil"
+	"log"
+	"os"
+	"path"
+	"path/filepath"
+	"strings"
+
+	"github.com/bazelbuild/bazel-gazelle/internal/config"
+	"github.com/bazelbuild/bazel-gazelle/internal/pathtools"
+	bf "github.com/bazelbuild/buildtools/build"
+)
+
+// A WalkFunc is a callback called by Walk in each visited directory.
+//
+// dir is the absolute file system path to the directory being visited.
+//
+// rel is the relative slash-separated path to the directory from the
+// repository root. Will be "" for the repository root directory itself.
+//
+// c is the configuration for the current directory. This may have been
+// modified by directives in the directory's build file.
+//
+// pkg contains information about how to build source code in the directory.
+// Will be nil for directories that don't contain buildable code, directories
+// that Gazelle was not asked update, and directories where Walk
+// encountered errors.
+//
+// oldFile is the existing build file in the directory. Will be nil if there
+// was no file.
+//
+// isUpdateDir is true for directories that Gazelle was asked to update.
+type WalkFunc func(dir, rel string, c *config.Config, pkg *Package, oldFile *bf.File, isUpdateDir bool)
+
+// Walk traverses a directory tree. In each directory, Walk parses existing
+// build files. In directories that Gazelle was asked to update (c.Dirs), Walk
+// also parses source files and infers build information.
+//
+// c is the base configuration for the repository. c may be copied and modified
+// by directives found in build files.
+//
+// root is an absolute file path to the directory to traverse.
+//
+// f is a function that will be called for each visited directory.
+func Walk(c *config.Config, root string, f WalkFunc) {
+	// Determine relative paths for the directories to be updated.
+	var updateRels []string
+	for _, dir := range c.Dirs {
+		rel, err := filepath.Rel(c.RepoRoot, dir)
+		if err != nil {
+			// This should have been verified when c was built.
+			log.Panicf("%s: not a subdirectory of repository root %q", dir, c.RepoRoot)
+		}
+		rel = filepath.ToSlash(rel)
+		if rel == "." || rel == "/" {
+			rel = ""
+		}
+		updateRels = append(updateRels, rel)
+	}
+	rootRel, err := filepath.Rel(c.RepoRoot, root)
+	if err != nil {
+		log.Panicf("%s: not a subdirectory of repository root %q", root, c.RepoRoot)
+	}
+	if rootRel == "." || rootRel == "/" {
+		rootRel = ""
+	}
+
+	symlinks := symlinkResolver{root: root, visited: []string{root}}
+
+	// visit walks the directory tree in post-order. It returns whether the
+	// given directory or any subdirectory contained a build file or buildable
+	// source code. This affects whether "testdata" directories are considered
+	// data dependencies.
+	var visit func(*config.Config, string, string, bool, []string) bool
+	visit = func(c *config.Config, dir, rel string, isUpdateDir bool, excluded []string) bool {
+		// Check if this directory should be updated.
+		if !isUpdateDir {
+			for _, updateRel := range updateRels {
+				if pathtools.HasPrefix(rel, updateRel) {
+					isUpdateDir = true
+				}
+			}
+		}
+
+		// Look for an existing BUILD file.
+		var oldFile *bf.File
+		haveError := false
+		for _, base := range c.ValidBuildFileNames {
+			oldPath := filepath.Join(dir, base)
+			st, err := os.Stat(oldPath)
+			if os.IsNotExist(err) || err == nil && st.IsDir() {
+				continue
+			}
+			oldData, err := ioutil.ReadFile(oldPath)
+			if err != nil {
+				log.Print(err)
+				haveError = true
+				continue
+			}
+			if oldFile != nil {
+				log.Printf("in directory %s, multiple Bazel files are present: %s, %s",
+					dir, filepath.Base(oldFile.Path), base)
+				haveError = true
+				continue
+			}
+			oldFile, err = bf.Parse(oldPath, oldData)
+			if err != nil {
+				log.Print(err)
+				haveError = true
+				continue
+			}
+		}
+
+		// Process directives in the build file. If this is a vendor directory,
+		// set an empty prefix.
+		if path.Base(rel) == "vendor" {
+			cCopy := *c
+			cCopy.GoPrefix = ""
+			cCopy.GoPrefixRel = rel
+			c = &cCopy
+		}
+		var directives []config.Directive
+		if oldFile != nil {
+			directives = config.ParseDirectives(oldFile)
+			c = config.ApplyDirectives(c, directives, rel)
+		}
+		c = config.InferProtoMode(c, rel, oldFile, directives)
+
+		var ignore bool
+		for _, d := range directives {
+			switch d.Key {
+			case "exclude":
+				excluded = append(excluded, d.Value)
+			case "ignore":
+				ignore = true
+			}
+		}
+
+		// List files and subdirectories.
+		files, err := ioutil.ReadDir(dir)
+		if err != nil {
+			log.Print(err)
+			return false
+		}
+		if c.ProtoMode == config.DefaultProtoMode {
+			excluded = append(excluded, findPbGoFiles(files, excluded)...)
+		}
+
+		var pkgFiles, otherFiles, subdirs []string
+		for _, f := range files {
+			base := f.Name()
+			switch {
+			case base == "" || base[0] == '.' || base[0] == '_' || isExcluded(excluded, base):
+				continue
+
+			case f.IsDir():
+				subdirs = append(subdirs, base)
+
+			case strings.HasSuffix(base, ".go") ||
+				(c.ProtoMode != config.DisableProtoMode && strings.HasSuffix(base, ".proto")):
+				pkgFiles = append(pkgFiles, base)
+
+			case f.Mode()&os.ModeSymlink != 0 && symlinks.follow(dir, base):
+				subdirs = append(subdirs, base)
+
+			default:
+				otherFiles = append(otherFiles, base)
+			}
+		}
+		// Recurse into subdirectories.
+		hasTestdata := false
+		subdirHasPackage := false
+		for _, sub := range subdirs {
+			subdirExcluded := excludedForSubdir(excluded, sub)
+			hasPackage := visit(c, filepath.Join(dir, sub), path.Join(rel, sub), isUpdateDir, subdirExcluded)
+			if sub == "testdata" && !hasPackage {
+				hasTestdata = true
+			}
+			subdirHasPackage = subdirHasPackage || hasPackage
+		}
+
+		hasPackage := subdirHasPackage || oldFile != nil
+		if haveError || !isUpdateDir || ignore {
+			f(dir, rel, c, nil, oldFile, false)
+			return hasPackage
+		}
+
+		// Build a package from files in this directory.
+		var genFiles []string
+		if oldFile != nil {
+			genFiles = findGenFiles(oldFile, excluded)
+		}
+		pkg := buildPackage(c, dir, rel, pkgFiles, otherFiles, genFiles, hasTestdata)
+		f(dir, rel, c, pkg, oldFile, true)
+		return hasPackage || pkg != nil
+	}
+
+	visit(c, root, rootRel, false, nil)
+}
+
+// buildPackage reads source files in a given directory and returns a Package
+// containing information about those files and how to build them.
+//
+// If no buildable .go files are found in the directory, nil will be returned.
+// If the directory contains multiple buildable packages, the package whose
+// name matches the directory base name will be returned. If there is no such
+// package or if an error occurs, an error will be logged, and nil will be
+// returned.
+func buildPackage(c *config.Config, dir, rel string, pkgFiles, otherFiles, genFiles []string, hasTestdata bool) *Package {
+	// Process .go and .proto files first, since these determine the package name.
+	packageMap := make(map[string]*packageBuilder)
+	cgo := false
+	var pkgFilesWithUnknownPackage []fileInfo
+	for _, f := range pkgFiles {
+		var info fileInfo
+		switch path.Ext(f) {
+		case ".go":
+			info = goFileInfo(c, dir, rel, f)
+		case ".proto":
+			info = protoFileInfo(c, dir, rel, f)
+		default:
+			log.Panicf("file cannot determine package name: %s", f)
+		}
+		if info.packageName == "" {
+			pkgFilesWithUnknownPackage = append(pkgFilesWithUnknownPackage, info)
+			continue
+		}
+		if info.packageName == "documentation" {
+			// go/build ignores this package
+			continue
+		}
+
+		cgo = cgo || info.isCgo
+
+		if _, ok := packageMap[info.packageName]; !ok {
+			packageMap[info.packageName] = &packageBuilder{
+				name:        info.packageName,
+				dir:         dir,
+				rel:         rel,
+				hasTestdata: hasTestdata,
+			}
+		}
+		if err := packageMap[info.packageName].addFile(c, info, false); err != nil {
+			log.Print(err)
+		}
+	}
+
+	// Select a package to generate rules for.
+	pkg, err := selectPackage(c, dir, packageMap)
+	if err != nil {
+		if _, ok := err.(*build.NoGoError); !ok {
+			log.Print(err)
+		}
+		return nil
+	}
+
+	// Add files with unknown packages. This happens when there are parse
+	// or I/O errors. We should keep the file in the srcs list and let the
+	// compiler deal with the error.
+	for _, info := range pkgFilesWithUnknownPackage {
+		if err := pkg.addFile(c, info, cgo); err != nil {
+			log.Print(err)
+		}
+	}
+
+	// Process the other static files.
+	for _, file := range otherFiles {
+		info := otherFileInfo(dir, rel, file)
+		if err := pkg.addFile(c, info, cgo); err != nil {
+			log.Print(err)
+		}
+	}
+
+	// Process generated files. Note that generated files may have the same names
+	// as static files. Bazel will use the generated files, but we will look at
+	// the content of static files, assuming they will be the same.
+	staticFiles := make(map[string]bool)
+	for _, f := range pkgFiles {
+		staticFiles[f] = true
+	}
+	for _, f := range otherFiles {
+		staticFiles[f] = true
+	}
+	for _, f := range genFiles {
+		if staticFiles[f] {
+			continue
+		}
+		info := fileNameInfo(dir, rel, f)
+		if err := pkg.addFile(c, info, cgo); err != nil {
+			log.Print(err)
+		}
+	}
+
+	if pkg.importPath == "" {
+		if err := pkg.inferImportPath(c); err != nil {
+			log.Print(err)
+			return nil
+		}
+	}
+	return pkg.build()
+}
+
+func selectPackage(c *config.Config, dir string, packageMap map[string]*packageBuilder) (*packageBuilder, error) {
+	buildablePackages := make(map[string]*packageBuilder)
+	for name, pkg := range packageMap {
+		if pkg.isBuildable(c) {
+			buildablePackages[name] = pkg
+		}
+	}
+
+	if len(buildablePackages) == 0 {
+		return nil, &build.NoGoError{Dir: dir}
+	}
+
+	if len(buildablePackages) == 1 {
+		for _, pkg := range buildablePackages {
+			return pkg, nil
+		}
+	}
+
+	if pkg, ok := buildablePackages[defaultPackageName(c, dir)]; ok {
+		return pkg, nil
+	}
+
+	err := &build.MultiplePackageError{Dir: dir}
+	for name, pkg := range buildablePackages {
+		// Add the first file for each package for the error message.
+		// Error() method expects these lists to be the same length. File
+		// lists must be non-empty. These lists are only created by
+		// buildPackage for packages with .go files present.
+		err.Packages = append(err.Packages, name)
+		err.Files = append(err.Files, pkg.firstGoFile())
+	}
+	return nil, err
+}
+
+func defaultPackageName(c *config.Config, dir string) string {
+	if dir != c.RepoRoot {
+		return filepath.Base(dir)
+	}
+	name := path.Base(c.GoPrefix)
+	if name == "." || name == "/" {
+		// This can happen if go_prefix is empty or is all slashes.
+		return "unnamed"
+	}
+	return name
+}
+
+func findGenFiles(f *bf.File, excluded []string) []string {
+	var strs []string
+	for _, r := range f.Rules("") {
+		for _, key := range []string{"out", "outs"} {
+			switch e := r.Attr(key).(type) {
+			case *bf.StringExpr:
+				strs = append(strs, e.Value)
+			case *bf.ListExpr:
+				for _, elem := range e.List {
+					if s, ok := elem.(*bf.StringExpr); ok {
+						strs = append(strs, s.Value)
+					}
+				}
+			}
+		}
+	}
+
+	var genFiles []string
+	for _, s := range strs {
+		if !isExcluded(excluded, s) {
+			genFiles = append(genFiles, s)
+		}
+	}
+	return genFiles
+}
+
+func findPbGoFiles(files []os.FileInfo, excluded []string) []string {
+	var pbGoFiles []string
+	for _, f := range files {
+		name := f.Name()
+		if strings.HasSuffix(name, ".proto") && !isExcluded(excluded, name) {
+			pbGoFiles = append(pbGoFiles, name[:len(name)-len(".proto")]+".pb.go")
+		}
+	}
+	return pbGoFiles
+}
+
+func isExcluded(excluded []string, base string) bool {
+	for _, e := range excluded {
+		if base == e {
+			return true
+		}
+	}
+	return false
+}
+
+func excludedForSubdir(excluded []string, subdir string) []string {
+	var filtered []string
+	for _, e := range excluded {
+		i := strings.IndexByte(e, '/')
+		if i < 0 || i == len(e)-1 || e[:i] != subdir {
+			continue
+		}
+		filtered = append(filtered, e[i+1:])
+	}
+	return filtered
+}
+
+type symlinkResolver struct {
+	root    string
+	visited []string
+}
+
+// Decide if symlink dir/base should be followed.
+func (r *symlinkResolver) follow(dir, base string) bool {
+	if dir == r.root && strings.HasPrefix(base, "bazel-") {
+		// Links such as bazel-<workspace>, bazel-out, bazel-genfiles are created by
+		// Bazel to point to internal build directories.
+		return false
+	}
+	// See if the symlink points to a tree that has been already visited.
+	fullpath := filepath.Join(dir, base)
+	dest, err := filepath.EvalSymlinks(fullpath)
+	if err != nil {
+		return false
+	}
+	if !filepath.IsAbs(dest) {
+		dest, err = filepath.Abs(filepath.Join(dir, dest))
+		if err != nil {
+			return false
+		}
+	}
+	for _, p := range r.visited {
+		if pathtools.HasPrefix(dest, p) || pathtools.HasPrefix(p, dest) {
+			return false
+		}
+	}
+	r.visited = append(r.visited, dest)
+	stat, err := os.Stat(fullpath)
+	if err != nil {
+		return false
+	}
+	return stat.IsDir()
+}

vendor/github.com/bazelbuild/bazel-gazelle/internal/pathtools/BUILD

@@ -0,0 +1,22 @@
+load("@io_bazel_rules_go//go:def.bzl", "go_library")
+
+go_library(
+    name = "go_default_library",
+    srcs = ["path.go"],
+    importpath = "github.com/bazelbuild/bazel-gazelle/internal/pathtools",
+    visibility = ["//vendor/github.com/bazelbuild/bazel-gazelle:__subpackages__"],
+)
+
+filegroup(
+    name = "package-srcs",
+    srcs = glob(["**"]),
+    tags = ["automanaged"],
+    visibility = ["//visibility:private"],
+)
+
+filegroup(
+    name = "all-srcs",
+    srcs = [":package-srcs"],
+    tags = ["automanaged"],
+    visibility = ["//visibility:public"],
+)

vendor/github.com/bazelbuild/bazel-gazelle/internal/pathtools/path.go

@@ -0,0 +1,63 @@
+/* Copyright 2018 The Bazel Authors. All rights reserved.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+   http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package pathtools
+
+import (
+	"path"
+	"path/filepath"
+	"strings"
+)
+
+// HasPrefix returns whether the slash-separated path p has the given
+// prefix. Unlike strings.HasPrefix, this function respects component
+// boundaries, so "/home/foo" is not a prefix is "/home/foobar/baz". If the
+// prefix is empty, this function always returns true.
+func HasPrefix(p, prefix string) bool {
+	return prefix == "" || p == prefix || strings.HasPrefix(p, prefix+"/")
+}
+
+// TrimPrefix returns p without the provided prefix. If p doesn't start
+// with prefix, it returns p unchanged. Unlike strings.HasPrefix, this function
+// respects component boundaries (assuming slash-separated paths), so
+// TrimPrefix("foo/bar", "foo") returns "baz".
+func TrimPrefix(p, prefix string) string {
+	if prefix == "" {
+		return p
+	}
+	if prefix == p {
+		return ""
+	}
+	return strings.TrimPrefix(p, prefix+"/")
+}
+
+// RelBaseName returns the base name for rel, a slash-separated path relative
+// to the repository root. If rel is empty, RelBaseName returns the base name
+// of prefix. If prefix is empty, RelBaseName returns the base name of root,
+// the absolute file path of the repository root directory. If that's empty
+// to, then RelBaseName returns "root".
+func RelBaseName(rel, prefix, root string) string {
+	base := path.Base(rel)
+	if base == "." || base == "/" {
+		base = path.Base(prefix)
+	}
+	if base == "." || base == "/" {
+		base = filepath.Base(root)
+	}
+	if base == "." || base == "/" {
+		base = "root"
+	}
+	return base
+}

vendor/github.com/bazelbuild/bazel-gazelle/internal/repos/BUILD

@@ -0,0 +1,34 @@
+load("@io_bazel_rules_go//go:def.bzl", "go_library")
+
+go_library(
+    name = "go_default_library",
+    srcs = [
+        "dep.go",
+        "remote.go",
+        "repo.go",
+    ],
+    importpath = "github.com/bazelbuild/bazel-gazelle/internal/repos",
+    visibility = ["//vendor/github.com/bazelbuild/bazel-gazelle:__subpackages__"],
+    deps = [
+        "//vendor/github.com/bazelbuild/bazel-gazelle/internal/label:go_default_library",
+        "//vendor/github.com/bazelbuild/bazel-gazelle/internal/pathtools:go_default_library",
+        "//vendor/github.com/bazelbuild/bazel-gazelle/internal/rules:go_default_library",
+        "//vendor/github.com/bazelbuild/buildtools/build:go_default_library",
+        "//vendor/github.com/pelletier/go-toml:go_default_library",
+        "//vendor/golang.org/x/tools/go/vcs:go_default_library",
+    ],
+)
+
+filegroup(
+    name = "package-srcs",
+    srcs = glob(["**"]),
+    tags = ["automanaged"],
+    visibility = ["//visibility:private"],
+)
+
+filegroup(
+    name = "all-srcs",
+    srcs = [":package-srcs"],
+    tags = ["automanaged"],
+    visibility = ["//visibility:public"],
+)

vendor/github.com/bazelbuild/bazel-gazelle/internal/repos/dep.go

@@ -0,0 +1,55 @@
+/* Copyright 2017 The Bazel Authors. All rights reserved.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+   http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package repos
+
+import (
+	"io/ioutil"
+
+	"github.com/bazelbuild/bazel-gazelle/internal/label"
+	toml "github.com/pelletier/go-toml"
+)
+
+type depLockFile struct {
+	Projects []depProject `toml:"projects"`
+}
+
+type depProject struct {
+	Name     string `toml:"name"`
+	Revision string `toml:"revision"`
+	Source   string `toml:"source"`
+}
+
+func importRepoRulesDep(filename string) ([]Repo, error) {
+	data, err := ioutil.ReadFile(filename)
+	if err != nil {
+		return nil, err
+	}
+	var file depLockFile
+	if err := toml.Unmarshal(data, &file); err != nil {
+		return nil, err
+	}
+
+	var repos []Repo
+	for _, p := range file.Projects {
+		repos = append(repos, Repo{
+			Name:     label.ImportPathToBazelRepoName(p.Name),
+			GoPrefix: p.Name,
+			Commit:   p.Revision,
+			Remote:   p.Source,
+		})
+	}
+	return repos, nil
+}

vendor/github.com/bazelbuild/bazel-gazelle/internal/repos/remote.go

@@ -0,0 +1,327 @@
+/* Copyright 2018 The Bazel Authors. All rights reserved.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+   http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package repos
+
+import (
+	"bytes"
+	"fmt"
+	"os/exec"
+	"path"
+	"regexp"
+	"strings"
+	"sync"
+
+	"github.com/bazelbuild/bazel-gazelle/internal/label"
+	"github.com/bazelbuild/bazel-gazelle/internal/pathtools"
+	"golang.org/x/tools/go/vcs"
+)
+
+// UpdateRepo returns an object describing a repository at the most recent
+// commit or version tag.
+//
+// This function uses RemoteCache to retrieve information about the repository.
+// Depending on how the RemoteCache was initialized and used earlier, some
+// information may already be locally available. Frequently though, information
+// will be fetched over the network, so this function may be slow.
+func UpdateRepo(rc *RemoteCache, importPath string) (Repo, error) {
+	root, name, err := rc.Root(importPath)
+	if err != nil {
+		return Repo{}, err
+	}
+	remote, vcs, err := rc.Remote(root)
+	if err != nil {
+		return Repo{}, err
+	}
+	commit, tag, err := rc.Head(remote, vcs)
+	if err != nil {
+		return Repo{}, err
+	}
+	repo := Repo{
+		Name:     name,
+		GoPrefix: root,
+		Commit:   commit,
+		Tag:      tag,
+		Remote:   remote,
+		VCS:      vcs,
+	}
+	return repo, nil
+}
+
+// RemoteCache stores information about external repositories. The cache may
+// be initialized with information about known repositories, i.e., those listed
+// in the WORKSPACE file and mentioned on the command line. Other information
+// is retrieved over the network.
+//
+// Public methods of RemoteCache may be slow in cases where a network fetch
+// is needed. Public methods may be called concurrently.
+type RemoteCache struct {
+	// RepoRootForImportPath is vcs.RepoRootForImportPath by default. It may
+	// be overridden so that tests may avoid accessing the network.
+	RepoRootForImportPath func(string, bool) (*vcs.RepoRoot, error)
+
+	// HeadCmd returns the latest commit on the default branch in the given
+	// repository. This is used by Head. It may be stubbed out for tests.
+	HeadCmd func(remote, vcs string) (string, error)
+
+	root, remote, head remoteCacheMap
+}
+
+// remoteCacheMap is a thread-safe, idempotent cache. It is used to store
+// information which should be fetched over the network no more than once.
+// This follows the Memo pattern described in The Go Programming Language,
+// section 9.7.
+type remoteCacheMap struct {
+	mu    sync.Mutex
+	cache map[string]*remoteCacheEntry
+}
+
+type remoteCacheEntry struct {
+	value interface{}
+	err   error
+
+	// ready is nil for entries that were added when the cache was initialized.
+	// It is non-nil for other entries. It is closed when an entry is ready,
+	// i.e., the operation loading the entry completed.
+	ready chan struct{}
+}
+
+type rootValue struct {
+	root, name string
+}
+
+type remoteValue struct {
+	remote, vcs string
+}
+
+type headValue struct {
+	commit, tag string
+}
+
+// NewRemoteCache creates a new RemoteCache with a set of known repositories.
+// The Root and Remote methods will return information about repositories listed
+// here without accessing the network. However, the Head method will still
+// access the network for these repositories to retrieve information about new
+// versions.
+func NewRemoteCache(knownRepos []Repo) *RemoteCache {
+	r := &RemoteCache{
+		RepoRootForImportPath: vcs.RepoRootForImportPath,
+		HeadCmd:               defaultHeadCmd,
+		root:                  remoteCacheMap{cache: make(map[string]*remoteCacheEntry)},
+		remote:                remoteCacheMap{cache: make(map[string]*remoteCacheEntry)},
+		head:                  remoteCacheMap{cache: make(map[string]*remoteCacheEntry)},
+	}
+	for _, repo := range knownRepos {
+		r.root.cache[repo.GoPrefix] = &remoteCacheEntry{
+			value: rootValue{
+				root: repo.GoPrefix,
+				name: repo.Name,
+			},
+		}
+		if repo.Remote != "" {
+			r.remote.cache[repo.GoPrefix] = &remoteCacheEntry{
+				value: remoteValue{
+					remote: repo.Remote,
+					vcs:    repo.VCS,
+				},
+			}
+		}
+	}
+	return r
+}
+
+var gopkginPattern = regexp.MustCompile("^(gopkg.in/(?:[^/]+/)?[^/]+\\.v\\d+)(?:/|$)")
+
+var knownPrefixes = []struct {
+	prefix  string
+	missing int
+}{
+	{prefix: "golang.org/x", missing: 1},
+	{prefix: "google.golang.org", missing: 1},
+	{prefix: "cloud.google.com", missing: 1},
+	{prefix: "github.com", missing: 2},
+}
+
+// Root returns the portion of an import path that corresponds to the root
+// directory of the repository containing the given import path. For example,
+// given "golang.org/x/tools/go/loader", this will return "golang.org/x/tools".
+// The workspace name of the repository is also returned. This may be a custom
+// name set in WORKSPACE, or it may be a generated name based on the root path.
+func (r *RemoteCache) Root(importPath string) (root, name string, err error) {
+	// Try prefixes of the import path in the cache, but don't actually go out
+	// to vcs yet. We do this before handling known special cases because
+	// the cache is pre-populated with repository rules, and we want to use their
+	// names if we can.
+	prefix := importPath
+	for {
+		v, ok, err := r.root.get(prefix)
+		if ok {
+			if err != nil {
+				return "", "", err
+			}
+			value := v.(rootValue)
+			return value.root, value.name, nil
+		}
+
+		prefix = path.Dir(prefix)
+		if prefix == "." || prefix == "/" {
+			break
+		}
+	}
+
+	// Try known prefixes.
+	for _, p := range knownPrefixes {
+		if pathtools.HasPrefix(importPath, p.prefix) {
+			rest := pathtools.TrimPrefix(importPath, p.prefix)
+			var components []string
+			if rest != "" {
+				components = strings.Split(rest, "/")
+			}
+			if len(components) < p.missing {
+				return "", "", fmt.Errorf("import path %q is shorter than the known prefix %q", importPath, p.prefix)
+			}
+			root = p.prefix
+			for _, c := range components[:p.missing] {
+				root = path.Join(root, c)
+			}
+			name = label.ImportPathToBazelRepoName(root)
+			return root, name, nil
+		}
+	}
+
+	// gopkg.in is special, and might have either one or two levels of
+	// missing paths. See http://labix.org/gopkg.in for URL patterns.
+	if match := gopkginPattern.FindStringSubmatch(importPath); len(match) > 0 {
+		root = match[1]
+		name = label.ImportPathToBazelRepoName(root)
+		return root, name, nil
+	}
+
+	// Find the prefix using vcs and cache the result.
+	v, err := r.root.ensure(importPath, func() (interface{}, error) {
+		res, err := r.RepoRootForImportPath(importPath, false)
+		if err != nil {
+			return nil, err
+		}
+		return rootValue{res.Root, label.ImportPathToBazelRepoName(res.Root)}, nil
+	})
+	if err != nil {
+		return "", "", err
+	}
+	value := v.(rootValue)
+	return value.root, value.name, nil
+}
+
+// Remote returns the VCS name and the remote URL for a repository with the
+// given root import path. This is suitable for creating new repository rules.
+func (r *RemoteCache) Remote(root string) (remote, vcs string, err error) {
+	v, err := r.remote.ensure(root, func() (interface{}, error) {
+		repo, err := r.RepoRootForImportPath(root, false)
+		if err != nil {
+			return nil, err
+		}
+		return remoteValue{remote: repo.Repo, vcs: repo.VCS.Cmd}, nil
+	})
+	if err != nil {
+		return "", "", err
+	}
+	value := v.(remoteValue)
+	return value.remote, value.vcs, nil
+}
+
+// Head returns the most recent commit id on the default branch and latest
+// version tag for the given remote repository. The tag "" is returned if
+// no latest version was found.
+//
+// TODO(jayconrod): support VCS other than git.
+// TODO(jayconrod): support version tags. "" is always returned.
+func (r *RemoteCache) Head(remote, vcs string) (commit, tag string, err error) {
+	if vcs != "git" {
+		return "", "", fmt.Errorf("could not locate recent commit in repo %q with unknown version control scheme %q", remote, vcs)
+	}
+
+	v, err := r.head.ensure(remote, func() (interface{}, error) {
+		commit, err := r.HeadCmd(remote, vcs)
+		if err != nil {
+			return nil, err
+		}
+		return headValue{commit: commit}, nil
+	})
+	if err != nil {
+		return "", "", err
+	}
+	value := v.(headValue)
+	return value.commit, value.tag, nil
+}
+
+func defaultHeadCmd(remote, vcs string) (string, error) {
+	switch vcs {
+	case "local":
+		return "", nil
+
+	case "git":
+		cmd := exec.Command("git", "ls-remote", "--", remote, "HEAD")
+		out, err := cmd.Output()
+		if err != nil {
+			return "", err
+		}
+		ix := bytes.IndexByte(out, '\t')
+		if ix < 0 {
+			return "", fmt.Errorf("could not parse output for git ls-remote for %q", remote)
+		}
+		return string(out[:ix]), nil
+
+	default:
+		return "", fmt.Errorf("unknown version control system: %s", vcs)
+	}
+}
+
+// get retrieves a value associated with the given key from the cache. ok will
+// be true if the key exists in the cache, even if it's in the process of
+// being fetched.
+func (m *remoteCacheMap) get(key string) (value interface{}, ok bool, err error) {
+	m.mu.Lock()
+	e, ok := m.cache[key]
+	m.mu.Unlock()
+	if !ok {
+		return nil, ok, nil
+	}
+	if e.ready != nil {
+		<-e.ready
+	}
+	return e.value, ok, e.err
+}
+
+// ensure retreives a value associated with the given key from the cache. If
+// the key does not exist in the cache, the load function will be called,
+// and its result will be associated with the key. The load function will not
+// be called more than once for any key.
+func (m *remoteCacheMap) ensure(key string, load func() (interface{}, error)) (interface{}, error) {
+	m.mu.Lock()
+	e, ok := m.cache[key]
+	if !ok {
+		e = &remoteCacheEntry{ready: make(chan struct{})}
+		m.cache[key] = e
+		m.mu.Unlock()
+		e.value, e.err = load()
+		close(e.ready)
+	} else {
+		m.mu.Unlock()
+		if e.ready != nil {
+			<-e.ready
+		}
+	}
+	return e.value, e.err
+}

vendor/github.com/bazelbuild/bazel-gazelle/internal/repos/repo.go

@@ -0,0 +1,198 @@
+/* Copyright 2017 The Bazel Authors. All rights reserved.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+   http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package repos
+
+import (
+	"fmt"
+	"os"
+	"path/filepath"
+	"sort"
+	"strings"
+
+	"github.com/bazelbuild/bazel-gazelle/internal/rules"
+	bf "github.com/bazelbuild/buildtools/build"
+)
+
+// Repo describes an external repository rule declared in a Bazel
+// WORKSPACE file.
+type Repo struct {
+	// Name is the value of the "name" attribute of the repository rule.
+	Name string
+
+	// GoPrefix is the portion of the Go import path for the root of this
+	// repository. Usually the same as Remote.
+	GoPrefix string
+
+	// Commit is the revision at which a repository is checked out (for example,
+	// a Git commit id).
+	Commit string
+
+	// Tag is the name of the version at which a repository is checked out.
+	Tag string
+
+	// Remote is the URL the repository can be cloned or checked out from.
+	Remote string
+
+	// VCS is the version control system used to check out the repository.
+	// May also be "http" for HTTP archives.
+	VCS string
+}
+
+type byName []Repo
+
+func (s byName) Len() int           { return len(s) }
+func (s byName) Less(i, j int) bool { return s[i].Name < s[j].Name }
+func (s byName) Swap(i, j int)      { s[i], s[j] = s[j], s[i] }
+
+type lockFileFormat int
+
+const (
+	unknownFormat lockFileFormat = iota
+	depFormat
+)
+
+var lockFileParsers = map[lockFileFormat]func(string) ([]Repo, error){
+	depFormat: importRepoRulesDep,
+}
+
+// ImportRepoRules reads the lock file of a vendoring tool and returns
+// a list of equivalent repository rules that can be merged into a WORKSPACE
+// file. The format of the file is inferred from its basename. Currently,
+// only Gopkg.lock is supported.
+func ImportRepoRules(filename string) ([]bf.Expr, error) {
+	format := getLockFileFormat(filename)
+	if format == unknownFormat {
+		return nil, fmt.Errorf(`%s: unrecognized lock file format. Expected "Gopkg.lock"`, filename)
+	}
+	parser := lockFileParsers[format]
+	repos, err := parser(filename)
+	if err != nil {
+		return nil, fmt.Errorf("error parsing %q: %v", filename, err)
+	}
+	sort.Stable(byName(repos))
+
+	rules := make([]bf.Expr, 0, len(repos))
+	for _, repo := range repos {
+		rules = append(rules, GenerateRule(repo))
+	}
+	return rules, nil
+}
+
+func getLockFileFormat(filename string) lockFileFormat {
+	switch filepath.Base(filename) {
+	case "Gopkg.lock":
+		return depFormat
+	default:
+		return unknownFormat
+	}
+}
+
+// GenerateRule returns a repository rule for the given repository that can
+// be written in a WORKSPACE file.
+func GenerateRule(repo Repo) bf.Expr {
+	attrs := []rules.KeyValue{
+		{Key: "name", Value: repo.Name},
+		{Key: "commit", Value: repo.Commit},
+		{Key: "importpath", Value: repo.GoPrefix},
+	}
+	if repo.Remote != "" {
+		attrs = append(attrs, rules.KeyValue{Key: "remote", Value: repo.Remote})
+	}
+	if repo.VCS != "" {
+		attrs = append(attrs, rules.KeyValue{Key: "vcs", Value: repo.VCS})
+	}
+	return rules.NewRule("go_repository", attrs)
+}
+
+// FindExternalRepo attempts to locate the directory where Bazel has fetched
+// the external repository with the given name. An error is returned if the
+// repository directory cannot be located.
+func FindExternalRepo(repoRoot, name string) (string, error) {
+	// See https://docs.bazel.build/versions/master/output_directories.html
+	// for documentation on Bazel directory layout.
+	// We expect the bazel-out symlink in the workspace root directory to point to
+	// <output-base>/execroot/<workspace-name>/bazel-out
+	// We expect the external repository to be checked out at
+	// <output-base>/external/<name>
+	// Note that users can change the prefix for most of the Bazel symlinks with
+	// --symlink_prefix, but this does not include bazel-out.
+	externalPath := strings.Join([]string{repoRoot, "bazel-out", "..", "..", "..", "external", name}, string(os.PathSeparator))
+	cleanPath, err := filepath.EvalSymlinks(externalPath)
+	if err != nil {
+		return "", err
+	}
+	st, err := os.Stat(cleanPath)
+	if err != nil {
+		return "", err
+	}
+	if !st.IsDir() {
+		return "", fmt.Errorf("%s: not a directory", externalPath)
+	}
+	return cleanPath, nil
+}
+
+// ListRepositories extracts metadata about repositories declared in a
+// WORKSPACE file.
+//
+// The set of repositories returned is necessarily incomplete, since we don't
+// evaluate the file, and repositories may be declared in macros in other files.
+func ListRepositories(workspace *bf.File) []Repo {
+	var repos []Repo
+	for _, e := range workspace.Stmt {
+		call, ok := e.(*bf.CallExpr)
+		if !ok {
+			continue
+		}
+		r := bf.Rule{Call: call}
+		name := r.Name()
+		if name == "" {
+			continue
+		}
+		var repo Repo
+		switch r.Kind() {
+		case "go_repository":
+			// TODO(jayconrod): extract other fields needed by go_repository.
+			// Currently, we don't use the result of this function to produce new
+			// go_repository rules, so it doesn't matter.
+			goPrefix := r.AttrString("importpath")
+			revision := r.AttrString("commit")
+			remote := r.AttrString("remote")
+			vcs := r.AttrString("vcs")
+			if goPrefix == "" {
+				continue
+			}
+			repo = Repo{
+				Name:     name,
+				GoPrefix: goPrefix,
+				Commit:   revision,
+				Remote:   remote,
+				VCS:      vcs,
+			}
+
+			// TODO(jayconrod): infer from {new_,}git_repository, {new_,}http_archive,
+			// local_repository.
+
+		default:
+			continue
+		}
+		repos = append(repos, repo)
+	}
+
+	// TODO(jayconrod): look for directives that describe repositories that
+	// aren't declared in the top-level of WORKSPACE (e.g., behind a macro).
+
+	return repos
+}

vendor/github.com/bazelbuild/bazel-gazelle/internal/resolve/BUILD

@@ -0,0 +1,35 @@
+load("@io_bazel_rules_go//go:def.bzl", "go_library")
+
+go_library(
+    name = "go_default_library",
+    srcs = [
+        "index.go",
+        "resolve.go",
+        "resolve_external.go",
+        "resolve_vendored.go",
+        "std_package_list.go",
+    ],
+    importpath = "github.com/bazelbuild/bazel-gazelle/internal/resolve",
+    visibility = ["//vendor/github.com/bazelbuild/bazel-gazelle:__subpackages__"],
+    deps = [
+        "//vendor/github.com/bazelbuild/bazel-gazelle/internal/config:go_default_library",
+        "//vendor/github.com/bazelbuild/bazel-gazelle/internal/label:go_default_library",
+        "//vendor/github.com/bazelbuild/bazel-gazelle/internal/pathtools:go_default_library",
+        "//vendor/github.com/bazelbuild/bazel-gazelle/internal/repos:go_default_library",
+        "//vendor/github.com/bazelbuild/buildtools/build:go_default_library",
+    ],
+)
+
+filegroup(
+    name = "package-srcs",
+    srcs = glob(["**"]),
+    tags = ["automanaged"],
+    visibility = ["//visibility:private"],
+)
+
+filegroup(
+    name = "all-srcs",
+    srcs = [":package-srcs"],
+    tags = ["automanaged"],
+    visibility = ["//visibility:public"],
+)

vendor/github.com/bazelbuild/bazel-gazelle/internal/resolve/index.go

@@ -0,0 +1,346 @@
+/* Copyright 2017 The Bazel Authors. All rights reserved.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+   http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package resolve
+
+import (
+	"fmt"
+	"log"
+	"path"
+	"path/filepath"
+	"strings"
+
+	"github.com/bazelbuild/bazel-gazelle/internal/config"
+	"github.com/bazelbuild/bazel-gazelle/internal/label"
+	bf "github.com/bazelbuild/buildtools/build"
+)
+
+// RuleIndex is a table of rules in a workspace, indexed by label and by
+// import path. Used by Resolver to map import paths to labels.
+type RuleIndex struct {
+	rules     []*ruleRecord
+	labelMap  map[label.Label]*ruleRecord
+	importMap map[importSpec][]*ruleRecord
+}
+
+// ruleRecord contains information about a rule relevant to import indexing.
+type ruleRecord struct {
+	rule       bf.Rule
+	label      label.Label
+	lang       config.Language
+	importedAs []importSpec
+	embedded   bool
+}
+
+// importSpec describes a package to be imported. Language is specified, since
+// different languages have different formats for their imports.
+type importSpec struct {
+	lang config.Language
+	imp  string
+}
+
+func NewRuleIndex() *RuleIndex {
+	return &RuleIndex{
+		labelMap: make(map[label.Label]*ruleRecord),
+	}
+}
+
+// AddRulesFromFile adds existing rules to the index from file
+// (which must not be nil).
+func (ix *RuleIndex) AddRulesFromFile(c *config.Config, file *bf.File) {
+	buildRel, err := filepath.Rel(c.RepoRoot, file.Path)
+	if err != nil {
+		log.Panicf("file not in repo: %s", file.Path)
+	}
+	buildRel = path.Dir(filepath.ToSlash(buildRel))
+	if buildRel == "." || buildRel == "/" {
+		buildRel = ""
+	}
+
+	for _, stmt := range file.Stmt {
+		if call, ok := stmt.(*bf.CallExpr); ok {
+			ix.addRule(call, c.GoPrefix, buildRel)
+		}
+	}
+}
+
+func (ix *RuleIndex) addRule(call *bf.CallExpr, goPrefix, buildRel string) {
+	rule := bf.Rule{Call: call}
+	record := &ruleRecord{
+		rule:  rule,
+		label: label.New("", buildRel, rule.Name()),
+	}
+
+	if _, ok := ix.labelMap[record.label]; ok {
+		log.Printf("multiple rules found with label %s", record.label)
+		return
+	}
+
+	kind := rule.Kind()
+	switch {
+	case isGoLibrary(kind):
+		record.lang = config.GoLang
+		if imp := rule.AttrString("importpath"); imp != "" {
+			record.importedAs = []importSpec{{lang: config.GoLang, imp: imp}}
+		}
+		// Additional proto imports may be added in Finish.
+
+	case kind == "proto_library":
+		record.lang = config.ProtoLang
+		for _, s := range findSources(rule, buildRel, ".proto") {
+			record.importedAs = append(record.importedAs, importSpec{lang: config.ProtoLang, imp: s})
+		}
+
+	default:
+		return
+	}
+
+	ix.rules = append(ix.rules, record)
+	ix.labelMap[record.label] = record
+}
+
+// Finish constructs the import index and performs any other necessary indexing
+// actions after all rules have been added. This step is necessary because
+// a rule may be indexed differently based on what rules are added later.
+//
+// This function must be called after all AddRulesFromFile calls but before any
+// findRuleByImport calls.
+func (ix *RuleIndex) Finish() {
+	ix.skipGoEmbds()
+	ix.buildImportIndex()
+}
+
+// skipGoEmbeds sets the embedded flag on Go library rules that are imported
+// by other Go library rules with the same import path. Note that embedded
+// rules may still be imported with non-Go imports. For example, a
+// go_proto_library may be imported with either a Go import path or a proto
+// path. If the library is embedded, only the proto path will be indexed.
+func (ix *RuleIndex) skipGoEmbds() {
+	for _, r := range ix.rules {
+		if !isGoLibrary(r.rule.Kind()) {
+			continue
+		}
+		importpath := r.rule.AttrString("importpath")
+
+		var embedLabels []label.Label
+		if embedList, ok := r.rule.Attr("embed").(*bf.ListExpr); ok {
+			for _, embedElem := range embedList.List {
+				embedStr, ok := embedElem.(*bf.StringExpr)
+				if !ok {
+					continue
+				}
+				embedLabel, err := label.Parse(embedStr.Value)
+				if err != nil {
+					continue
+				}
+				embedLabels = append(embedLabels, embedLabel)
+			}
+		}
+		if libraryStr, ok := r.rule.Attr("library").(*bf.StringExpr); ok {
+			if libraryLabel, err := label.Parse(libraryStr.Value); err == nil {
+				embedLabels = append(embedLabels, libraryLabel)
+			}
+		}
+
+		for _, l := range embedLabels {
+			embed, ok := ix.findRuleByLabel(l, r.label)
+			if !ok {
+				continue
+			}
+			if embed.rule.AttrString("importpath") != importpath {
+				continue
+			}
+			embed.embedded = true
+		}
+	}
+}
+
+// buildImportIndex constructs the map used by findRuleByImport.
+func (ix *RuleIndex) buildImportIndex() {
+	ix.importMap = make(map[importSpec][]*ruleRecord)
+	for _, r := range ix.rules {
+		if isGoProtoLibrary(r.rule.Kind()) {
+			protoImports := findGoProtoSources(ix, r)
+			r.importedAs = append(r.importedAs, protoImports...)
+		}
+		for _, imp := range r.importedAs {
+			if imp.lang == config.GoLang && r.embedded {
+				continue
+			}
+			ix.importMap[imp] = append(ix.importMap[imp], r)
+		}
+	}
+}
+
+type ruleNotFoundError struct {
+	from label.Label
+	imp  string
+}
+
+func (e ruleNotFoundError) Error() string {
+	return fmt.Sprintf("no rule found for import %q, needed in %s", e.imp, e.from)
+}
+
+type selfImportError struct {
+	from label.Label
+	imp  string
+}
+
+func (e selfImportError) Error() string {
+	return fmt.Sprintf("rule %s imports itself with path %q", e.from, e.imp)
+}
+
+func (ix *RuleIndex) findRuleByLabel(label label.Label, from label.Label) (*ruleRecord, bool) {
+	label = label.Abs(from.Repo, from.Pkg)
+	r, ok := ix.labelMap[label]
+	return r, ok
+}
+
+// findRuleByImport attempts to resolve an import string to a rule record.
+// imp is the import to resolve (which includes the target language). lang is
+// the language of the rule with the dependency (for example, in
+// go_proto_library, imp will have ProtoLang and lang will be GoLang).
+// from is the rule which is doing the dependency. This is used to check
+// vendoring visibility and to check for self-imports.
+//
+// Any number of rules may provide the same import. If no rules provide the
+// import, ruleNotFoundError is returned. If a rule imports itself,
+// selfImportError is returned. If multiple rules provide the import, this
+// function will attempt to choose one based on Go vendoring logic.  In
+// ambiguous cases, an error is returned.
+func (ix *RuleIndex) findRuleByImport(imp importSpec, lang config.Language, from label.Label) (*ruleRecord, error) {
+	matches := ix.importMap[imp]
+	var bestMatch *ruleRecord
+	var bestMatchIsVendored bool
+	var bestMatchVendorRoot string
+	var matchError error
+	for _, m := range matches {
+		if m.lang != lang {
+			continue
+		}
+
+		switch imp.lang {
+		case config.GoLang:
+			// Apply vendoring logic for Go libraries. A library in a vendor directory
+			// is only visible in the parent tree. Vendored libraries supercede
+			// non-vendored libraries, and libraries closer to from.Pkg supercede
+			// those further up the tree.
+			isVendored := false
+			vendorRoot := ""
+			parts := strings.Split(m.label.Pkg, "/")
+			for i := len(parts) - 1; i >= 0; i-- {
+				if parts[i] == "vendor" {
+					isVendored = true
+					vendorRoot = strings.Join(parts[:i], "/")
+					break
+				}
+			}
+			if isVendored && !label.New(m.label.Repo, vendorRoot, "").Contains(from) {
+				// vendor directory not visible
+				continue
+			}
+			if bestMatch == nil || isVendored && (!bestMatchIsVendored || len(vendorRoot) > len(bestMatchVendorRoot)) {
+				// Current match is better
+				bestMatch = m
+				bestMatchIsVendored = isVendored
+				bestMatchVendorRoot = vendorRoot
+				matchError = nil
+			} else if (!isVendored && bestMatchIsVendored) || (isVendored && len(vendorRoot) < len(bestMatchVendorRoot)) {
+				// Current match is worse
+			} else {
+				// Match is ambiguous
+				matchError = fmt.Errorf("multiple rules (%s and %s) may be imported with %q from %s", bestMatch.label, m.label, imp.imp, from)
+			}
+
+		default:
+			if bestMatch == nil {
+				bestMatch = m
+			} else {
+				matchError = fmt.Errorf("multiple rules (%s and %s) may be imported with %q from %s", bestMatch.label, m.label, imp.imp, from)
+			}
+		}
+	}
+	if matchError != nil {
+		return nil, matchError
+	}
+	if bestMatch == nil {
+		return nil, ruleNotFoundError{from, imp.imp}
+	}
+	if bestMatch.label.Equal(from) {
+		return nil, selfImportError{from, imp.imp}
+	}
+
+	if imp.lang == config.ProtoLang && lang == config.GoLang {
+		importpath := bestMatch.rule.AttrString("importpath")
+		if betterMatch, err := ix.findRuleByImport(importSpec{config.GoLang, importpath}, config.GoLang, from); err == nil {
+			return betterMatch, nil
+		}
+	}
+
+	return bestMatch, nil
+}
+
+func (ix *RuleIndex) findLabelByImport(imp importSpec, lang config.Language, from label.Label) (label.Label, error) {
+	r, err := ix.findRuleByImport(imp, lang, from)
+	if err != nil {
+		return label.NoLabel, err
+	}
+	return r.label, nil
+}
+
+func findGoProtoSources(ix *RuleIndex, r *ruleRecord) []importSpec {
+	protoLabel, err := label.Parse(r.rule.AttrString("proto"))
+	if err != nil {
+		return nil
+	}
+	proto, ok := ix.findRuleByLabel(protoLabel, r.label)
+	if !ok {
+		return nil
+	}
+	var importedAs []importSpec
+	for _, source := range findSources(proto.rule, proto.label.Pkg, ".proto") {
+		importedAs = append(importedAs, importSpec{lang: config.ProtoLang, imp: source})
+	}
+	return importedAs
+}
+
+func findSources(r bf.Rule, buildRel, ext string) []string {
+	srcsExpr := r.Attr("srcs")
+	srcsList, ok := srcsExpr.(*bf.ListExpr)
+	if !ok {
+		return nil
+	}
+	var srcs []string
+	for _, srcExpr := range srcsList.List {
+		src, ok := srcExpr.(*bf.StringExpr)
+		if !ok {
+			continue
+		}
+		label, err := label.Parse(src.Value)
+		if err != nil || !label.Relative || !strings.HasSuffix(label.Name, ext) {
+			continue
+		}
+		srcs = append(srcs, path.Join(buildRel, label.Name))
+	}
+	return srcs
+}
+
+func isGoLibrary(kind string) bool {
+	return kind == "go_library" || isGoProtoLibrary(kind)
+}
+
+func isGoProtoLibrary(kind string) bool {
+	return kind == "go_proto_library" || kind == "go_grpc_library"
+}

vendor/github.com/bazelbuild/bazel-gazelle/internal/resolve/resolve.go

@@ -0,0 +1,350 @@
+/* Copyright 2016 The Bazel Authors. All rights reserved.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+   http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package resolve
+
+import (
+	"fmt"
+	"go/build"
+	"log"
+	"path"
+	"strings"
+
+	"github.com/bazelbuild/bazel-gazelle/internal/config"
+	"github.com/bazelbuild/bazel-gazelle/internal/label"
+	"github.com/bazelbuild/bazel-gazelle/internal/pathtools"
+	"github.com/bazelbuild/bazel-gazelle/internal/repos"
+	bf "github.com/bazelbuild/buildtools/build"
+)
+
+// Resolver resolves import strings in source files (import paths in Go,
+// import statements in protos) into Bazel labels.
+type Resolver struct {
+	c        *config.Config
+	l        *label.Labeler
+	ix       *RuleIndex
+	external nonlocalResolver
+}
+
+// nonlocalResolver resolves import paths outside of the current repository's
+// prefix. Once we have smarter import path resolution, this shouldn't
+// be necessary, and we can remove this abstraction.
+type nonlocalResolver interface {
+	resolve(imp string) (label.Label, error)
+}
+
+func NewResolver(c *config.Config, l *label.Labeler, ix *RuleIndex, rc *repos.RemoteCache) *Resolver {
+	var e nonlocalResolver
+	switch c.DepMode {
+	case config.ExternalMode:
+		e = newExternalResolver(l, rc)
+	case config.VendorMode:
+		e = newVendoredResolver(l)
+	}
+
+	return &Resolver{
+		c:        c,
+		l:        l,
+		ix:       ix,
+		external: e,
+	}
+}
+
+// ResolveRule copies and modifies a generated rule e by replacing the import
+// paths in the "_gazelle_imports" attribute with labels in a "deps"
+// attribute. This may be safely called on expressions that aren't Go rules
+// (the original expression will be returned). Any existing "deps" attribute
+// is deleted, so it may be necessary to merge the result.
+func (r *Resolver) ResolveRule(e bf.Expr, pkgRel string) bf.Expr {
+	call, ok := e.(*bf.CallExpr)
+	if !ok {
+		return e
+	}
+	rule := bf.Rule{Call: call}
+	from := label.New("", pkgRel, rule.Name())
+
+	var resolve func(imp string, from label.Label) (label.Label, error)
+	switch rule.Kind() {
+	case "go_library", "go_binary", "go_test":
+		resolve = r.resolveGo
+	case "proto_library":
+		resolve = r.resolveProto
+	case "go_proto_library", "go_grpc_library":
+		resolve = r.resolveGoProto
+	default:
+		return e
+	}
+
+	resolved := *call
+	resolved.List = append([]bf.Expr{}, call.List...)
+	rule.Call = &resolved
+
+	imports := rule.Attr(config.GazelleImportsKey)
+	rule.DelAttr(config.GazelleImportsKey)
+	rule.DelAttr("deps")
+	deps := mapExprStrings(imports, func(imp string) string {
+		label, err := resolve(imp, from)
+		if err != nil {
+			switch err.(type) {
+			case standardImportError, selfImportError:
+				return ""
+			default:
+				log.Print(err)
+				return ""
+			}
+		}
+		label.Relative = label.Repo == "" && label.Pkg == pkgRel
+		return label.String()
+	})
+	if deps != nil {
+		rule.SetAttr("deps", deps)
+	}
+
+	return &resolved
+}
+
+type standardImportError struct {
+	imp string
+}
+
+func (e standardImportError) Error() string {
+	return fmt.Sprintf("import path %q is in the standard library", e.imp)
+}
+
+// mapExprStrings applies a function f to the strings in e and returns a new
+// expression with the results. Scalar strings, lists, dicts, selects, and
+// concatenations are supported.
+func mapExprStrings(e bf.Expr, f func(string) string) bf.Expr {
+	if e == nil {
+		return nil
+	}
+	switch expr := e.(type) {
+	case *bf.StringExpr:
+		s := f(expr.Value)
+		if s == "" {
+			return nil
+		}
+		ret := *expr
+		ret.Value = s
+		return &ret
+
+	case *bf.ListExpr:
+		var list []bf.Expr
+		for _, elem := range expr.List {
+			elem = mapExprStrings(elem, f)
+			if elem != nil {
+				list = append(list, elem)
+			}
+		}
+		if len(list) == 0 && len(expr.List) > 0 {
+			return nil
+		}
+		ret := *expr
+		ret.List = list
+		return &ret
+
+	case *bf.DictExpr:
+		var cases []bf.Expr
+		isEmpty := true
+		for _, kv := range expr.List {
+			keyval, ok := kv.(*bf.KeyValueExpr)
+			if !ok {
+				log.Panicf("unexpected expression in generated imports dict: %#v", kv)
+			}
+			value := mapExprStrings(keyval.Value, f)
+			if value != nil {
+				cases = append(cases, &bf.KeyValueExpr{Key: keyval.Key, Value: value})
+				if key, ok := keyval.Key.(*bf.StringExpr); !ok || key.Value != "//conditions:default" {
+					isEmpty = false
+				}
+			}
+		}
+		if isEmpty {
+			return nil
+		}
+		ret := *expr
+		ret.List = cases
+		return &ret
+
+	case *bf.CallExpr:
+		if x, ok := expr.X.(*bf.LiteralExpr); !ok || x.Token != "select" || len(expr.List) != 1 {
+			log.Panicf("unexpected call expression in generated imports: %#v", e)
+		}
+		arg := mapExprStrings(expr.List[0], f)
+		if arg == nil {
+			return nil
+		}
+		call := *expr
+		call.List[0] = arg
+		return &call
+
+	case *bf.BinaryExpr:
+		x := mapExprStrings(expr.X, f)
+		y := mapExprStrings(expr.Y, f)
+		if x == nil {
+			return y
+		}
+		if y == nil {
+			return x
+		}
+		binop := *expr
+		binop.X = x
+		binop.Y = y
+		return &binop
+
+	default:
+		log.Panicf("unexpected expression in generated imports: %#v", e)
+		return nil
+	}
+}
+
+// resolveGo resolves an import path from a Go source file to a label.
+// pkgRel is the path to the Go package relative to the repository root; it
+// is used to resolve relative imports.
+func (r *Resolver) resolveGo(imp string, from label.Label) (label.Label, error) {
+	if build.IsLocalImport(imp) {
+		cleanRel := path.Clean(path.Join(from.Pkg, imp))
+		if build.IsLocalImport(cleanRel) {
+			return label.NoLabel, fmt.Errorf("relative import path %q from %q points outside of repository", imp, from.Pkg)
+		}
+		imp = path.Join(r.c.GoPrefix, cleanRel)
+	}
+
+	if IsStandard(imp) {
+		return label.NoLabel, standardImportError{imp}
+	}
+
+	if l, err := r.ix.findLabelByImport(importSpec{config.GoLang, imp}, config.GoLang, from); err != nil {
+		if _, ok := err.(ruleNotFoundError); !ok {
+			return label.NoLabel, err
+		}
+	} else {
+		return l, nil
+	}
+
+	if pathtools.HasPrefix(imp, r.c.GoPrefix) {
+		return r.l.LibraryLabel(pathtools.TrimPrefix(imp, r.c.GoPrefix)), nil
+	}
+
+	return r.external.resolve(imp)
+}
+
+const (
+	wellKnownPrefix     = "google/protobuf/"
+	wellKnownGoProtoPkg = "ptypes"
+	descriptorPkg       = "protoc-gen-go/descriptor"
+)
+
+// resolveProto resolves an import statement in a .proto file to a label
+// for a proto_library rule.
+func (r *Resolver) resolveProto(imp string, from label.Label) (label.Label, error) {
+	if !strings.HasSuffix(imp, ".proto") {
+		return label.NoLabel, fmt.Errorf("can't import non-proto: %q", imp)
+	}
+	if isWellKnown(imp) {
+		name := path.Base(imp[:len(imp)-len(".proto")]) + "_proto"
+		return label.New(config.WellKnownTypesProtoRepo, "", name), nil
+	}
+
+	if l, err := r.ix.findLabelByImport(importSpec{config.ProtoLang, imp}, config.ProtoLang, from); err != nil {
+		if _, ok := err.(ruleNotFoundError); !ok {
+			return label.NoLabel, err
+		}
+	} else {
+		return l, nil
+	}
+
+	rel := path.Dir(imp)
+	if rel == "." {
+		rel = ""
+	}
+	name := pathtools.RelBaseName(rel, r.c.GoPrefix, r.c.RepoRoot)
+	return r.l.ProtoLabel(rel, name), nil
+}
+
+// resolveGoProto resolves an import statement in a .proto file to a
+// label for a go_library rule that embeds the corresponding go_proto_library.
+func (r *Resolver) resolveGoProto(imp string, from label.Label) (label.Label, error) {
+	if !strings.HasSuffix(imp, ".proto") {
+		return label.NoLabel, fmt.Errorf("can't import non-proto: %q", imp)
+	}
+	stem := imp[:len(imp)-len(".proto")]
+
+	if isWellKnown(stem) {
+		// Well Known Type
+		base := path.Base(stem)
+		if base == "descriptor" {
+			switch r.c.DepMode {
+			case config.ExternalMode:
+				label := r.l.LibraryLabel(descriptorPkg)
+				if r.c.GoPrefix != config.WellKnownTypesGoPrefix {
+					label.Repo = config.WellKnownTypesGoProtoRepo
+				}
+				return label, nil
+			case config.VendorMode:
+				pkg := path.Join("vendor", config.WellKnownTypesGoPrefix, descriptorPkg)
+				label := r.l.LibraryLabel(pkg)
+				return label, nil
+			default:
+				log.Panicf("unknown external mode: %v", r.c.DepMode)
+			}
+		}
+
+		switch r.c.DepMode {
+		case config.ExternalMode:
+			pkg := path.Join(wellKnownGoProtoPkg, base)
+			label := r.l.LibraryLabel(pkg)
+			if r.c.GoPrefix != config.WellKnownTypesGoPrefix {
+				label.Repo = config.WellKnownTypesGoProtoRepo
+			}
+			return label, nil
+		case config.VendorMode:
+			pkg := path.Join("vendor", config.WellKnownTypesGoPrefix, wellKnownGoProtoPkg, base)
+			return r.l.LibraryLabel(pkg), nil
+		default:
+			log.Panicf("unknown external mode: %v", r.c.DepMode)
+		}
+	}
+
+	if l, err := r.ix.findLabelByImport(importSpec{config.ProtoLang, imp}, config.GoLang, from); err != nil {
+		if _, ok := err.(ruleNotFoundError); !ok {
+			return label.NoLabel, err
+		}
+	} else {
+		return l, err
+	}
+
+	// As a fallback, guess the label based on the proto file name. We assume
+	// all proto files in a directory belong to the same package, and the
+	// package name matches the directory base name. We also assume that protos
+	// in the vendor directory must refer to something else in vendor.
+	rel := path.Dir(imp)
+	if rel == "." {
+		rel = ""
+	}
+	if from.Pkg == "vendor" || strings.HasPrefix(from.Pkg, "vendor/") {
+		rel = path.Join("vendor", rel)
+	}
+	return r.l.LibraryLabel(rel), nil
+}
+
+// IsStandard returns whether a package is in the standard library.
+func IsStandard(imp string) bool {
+	return stdPackages[imp]
+}
+
+func isWellKnown(imp string) bool {
+	return strings.HasPrefix(imp, wellKnownPrefix) && strings.TrimPrefix(imp, wellKnownPrefix) == path.Base(imp)
+}

vendor/github.com/bazelbuild/bazel-gazelle/internal/resolve/resolve_external.go

@@ -0,0 +1,59 @@
+/* Copyright 2016 The Bazel Authors. All rights reserved.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+   http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package resolve
+
+import (
+	"github.com/bazelbuild/bazel-gazelle/internal/label"
+	"github.com/bazelbuild/bazel-gazelle/internal/pathtools"
+	"github.com/bazelbuild/bazel-gazelle/internal/repos"
+)
+
+// externalResolver resolves import paths to external repositories. It uses
+// vcs to determine the prefix of the import path that corresponds to the root
+// of the repository (this will perform a network fetch for unqualified paths).
+// The prefix is converted to a Bazel external name repo according to the
+// guidelines in http://bazel.io/docs/be/functions.html#workspace. The remaining
+// portion of the import path is treated as the package name.
+type externalResolver struct {
+	l  *label.Labeler
+	rc *repos.RemoteCache
+}
+
+var _ nonlocalResolver = (*externalResolver)(nil)
+
+func newExternalResolver(l *label.Labeler, rc *repos.RemoteCache) *externalResolver {
+	return &externalResolver{l: l, rc: rc}
+}
+
+// Resolve resolves "importPath" into a label, assuming that it is a label in an
+// external repository. It also assumes that the external repository follows the
+// recommended reverse-DNS form of workspace name as described in
+// http://bazel.io/docs/be/functions.html#workspace.
+func (r *externalResolver) resolve(importPath string) (label.Label, error) {
+	prefix, repo, err := r.rc.Root(importPath)
+	if err != nil {
+		return label.NoLabel, err
+	}
+
+	var pkg string
+	if importPath != prefix {
+		pkg = pathtools.TrimPrefix(importPath, prefix)
+	}
+
+	l := r.l.LibraryLabel(pkg)
+	l.Repo = repo
+	return l, nil
+}

vendor/github.com/bazelbuild/bazel-gazelle/internal/resolve/resolve_vendored.go

@@ -0,0 +1,35 @@
+/* Copyright 2016 The Bazel Authors. All rights reserved.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+   http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package resolve
+
+import (
+	"github.com/bazelbuild/bazel-gazelle/internal/label"
+)
+
+// vendoredResolver resolves external packages as packages in vendor/.
+type vendoredResolver struct {
+	l *label.Labeler
+}
+
+var _ nonlocalResolver = (*vendoredResolver)(nil)
+
+func newVendoredResolver(l *label.Labeler) *vendoredResolver {
+	return &vendoredResolver{l}
+}
+
+func (v *vendoredResolver) resolve(importpath string) (label.Label, error) {
+	return v.l.LibraryLabel("vendor/" + importpath), nil
+}

vendor/github.com/bazelbuild/bazel-gazelle/internal/resolve/std_package_list.go

@@ -0,0 +1,273 @@
+
+/* Copyright 2017 The Bazel Authors. All rights reserved.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+   http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+// Generated by gen_std_package_list.go
+// DO NOT EDIT
+
+package resolve
+
+var stdPackages = map[string]bool{
+	"archive/tar": true,
+	"archive/zip": true,
+	"bufio": true,
+	"bytes": true,
+	"cmd/addr2line": true,
+	"cmd/api": true,
+	"cmd/asm": true,
+	"cmd/asm/internal/arch": true,
+	"cmd/asm/internal/asm": true,
+	"cmd/asm/internal/flags": true,
+	"cmd/asm/internal/lex": true,
+	"cmd/cgo": true,
+	"cmd/compile": true,
+	"cmd/compile/internal/amd64": true,
+	"cmd/compile/internal/arm": true,
+	"cmd/compile/internal/arm64": true,
+	"cmd/compile/internal/gc": true,
+	"cmd/compile/internal/mips": true,
+	"cmd/compile/internal/mips64": true,
+	"cmd/compile/internal/ppc64": true,
+	"cmd/compile/internal/s390x": true,
+	"cmd/compile/internal/ssa": true,
+	"cmd/compile/internal/syntax": true,
+	"cmd/compile/internal/test": true,
+	"cmd/compile/internal/types": true,
+	"cmd/compile/internal/x86": true,
+	"cmd/cover": true,
+	"cmd/dist": true,
+	"cmd/doc": true,
+	"cmd/fix": true,
+	"cmd/go": true,
+	"cmd/go/internal/base": true,
+	"cmd/go/internal/bug": true,
+	"cmd/go/internal/buildid": true,
+	"cmd/go/internal/cfg": true,
+	"cmd/go/internal/clean": true,
+	"cmd/go/internal/cmdflag": true,
+	"cmd/go/internal/doc": true,
+	"cmd/go/internal/envcmd": true,
+	"cmd/go/internal/fix": true,
+	"cmd/go/internal/fmtcmd": true,
+	"cmd/go/internal/generate": true,
+	"cmd/go/internal/get": true,
+	"cmd/go/internal/help": true,
+	"cmd/go/internal/list": true,
+	"cmd/go/internal/load": true,
+	"cmd/go/internal/run": true,
+	"cmd/go/internal/str": true,
+	"cmd/go/internal/test": true,
+	"cmd/go/internal/tool": true,
+	"cmd/go/internal/version": true,
+	"cmd/go/internal/vet": true,
+	"cmd/go/internal/web": true,
+	"cmd/go/internal/work": true,
+	"cmd/gofmt": true,
+	"cmd/internal/bio": true,
+	"cmd/internal/browser": true,
+	"cmd/internal/dwarf": true,
+	"cmd/internal/gcprog": true,
+	"cmd/internal/goobj": true,
+	"cmd/internal/obj": true,
+	"cmd/internal/obj/arm": true,
+	"cmd/internal/obj/arm64": true,
+	"cmd/internal/obj/mips": true,
+	"cmd/internal/obj/ppc64": true,
+	"cmd/internal/obj/s390x": true,
+	"cmd/internal/obj/x86": true,
+	"cmd/internal/objabi": true,
+	"cmd/internal/objfile": true,
+	"cmd/internal/src": true,
+	"cmd/internal/sys": true,
+	"cmd/link": true,
+	"cmd/link/internal/amd64": true,
+	"cmd/link/internal/arm": true,
+	"cmd/link/internal/arm64": true,
+	"cmd/link/internal/ld": true,
+	"cmd/link/internal/mips": true,
+	"cmd/link/internal/mips64": true,
+	"cmd/link/internal/ppc64": true,
+	"cmd/link/internal/s390x": true,
+	"cmd/link/internal/x86": true,
+	"cmd/nm": true,
+	"cmd/objdump": true,
+	"cmd/pack": true,
+	"cmd/pprof": true,
+	"cmd/trace": true,
+	"cmd/vet": true,
+	"cmd/vet/internal/cfg": true,
+	"cmd/vet/internal/whitelist": true,
+	"compress/bzip2": true,
+	"compress/flate": true,
+	"compress/gzip": true,
+	"compress/lzw": true,
+	"compress/zlib": true,
+	"container/heap": true,
+	"container/list": true,
+	"container/ring": true,
+	"context": true,
+	"crypto": true,
+	"crypto/aes": true,
+	"crypto/cipher": true,
+	"crypto/des": true,
+	"crypto/dsa": true,
+	"crypto/ecdsa": true,
+	"crypto/elliptic": true,
+	"crypto/hmac": true,
+	"crypto/internal/cipherhw": true,
+	"crypto/md5": true,
+	"crypto/rand": true,
+	"crypto/rc4": true,
+	"crypto/rsa": true,
+	"crypto/sha1": true,
+	"crypto/sha256": true,
+	"crypto/sha512": true,
+	"crypto/subtle": true,
+	"crypto/tls": true,
+	"crypto/x509": true,
+	"crypto/x509/pkix": true,
+	"database/sql": true,
+	"database/sql/driver": true,
+	"debug/dwarf": true,
+	"debug/elf": true,
+	"debug/gosym": true,
+	"debug/macho": true,
+	"debug/pe": true,
+	"debug/plan9obj": true,
+	"encoding": true,
+	"encoding/ascii85": true,
+	"encoding/asn1": true,
+	"encoding/base32": true,
+	"encoding/base64": true,
+	"encoding/binary": true,
+	"encoding/csv": true,
+	"encoding/gob": true,
+	"encoding/hex": true,
+	"encoding/json": true,
+	"encoding/pem": true,
+	"encoding/xml": true,
+	"errors": true,
+	"expvar": true,
+	"flag": true,
+	"fmt": true,
+	"go/ast": true,
+	"go/build": true,
+	"go/constant": true,
+	"go/doc": true,
+	"go/format": true,
+	"go/importer": true,
+	"go/internal/gccgoimporter": true,
+	"go/internal/gcimporter": true,
+	"go/internal/srcimporter": true,
+	"go/parser": true,
+	"go/printer": true,
+	"go/scanner": true,
+	"go/token": true,
+	"go/types": true,
+	"hash": true,
+	"hash/adler32": true,
+	"hash/crc32": true,
+	"hash/crc64": true,
+	"hash/fnv": true,
+	"html": true,
+	"html/template": true,
+	"image": true,
+	"image/color": true,
+	"image/color/palette": true,
+	"image/draw": true,
+	"image/gif": true,
+	"image/internal/imageutil": true,
+	"image/jpeg": true,
+	"image/png": true,
+	"index/suffixarray": true,
+	"internal/cpu": true,
+	"internal/nettrace": true,
+	"internal/poll": true,
+	"internal/race": true,
+	"internal/singleflight": true,
+	"internal/syscall/unix": true,
+	"internal/syscall/windows": true,
+	"internal/syscall/windows/registry": true,
+	"internal/syscall/windows/sysdll": true,
+	"internal/testenv": true,
+	"internal/trace": true,
+	"io": true,
+	"io/ioutil": true,
+	"log": true,
+	"log/syslog": true,
+	"math": true,
+	"math/big": true,
+	"math/bits": true,
+	"math/cmplx": true,
+	"math/rand": true,
+	"mime": true,
+	"mime/multipart": true,
+	"mime/quotedprintable": true,
+	"net": true,
+	"net/http": true,
+	"net/http/cgi": true,
+	"net/http/cookiejar": true,
+	"net/http/fcgi": true,
+	"net/http/httptest": true,
+	"net/http/httptrace": true,
+	"net/http/httputil": true,
+	"net/http/internal": true,
+	"net/http/pprof": true,
+	"net/internal/socktest": true,
+	"net/mail": true,
+	"net/rpc": true,
+	"net/rpc/jsonrpc": true,
+	"net/smtp": true,
+	"net/textproto": true,
+	"net/url": true,
+	"os": true,
+	"os/exec": true,
+	"os/signal": true,
+	"os/user": true,
+	"path": true,
+	"path/filepath": true,
+	"plugin": true,
+	"reflect": true,
+	"regexp": true,
+	"regexp/syntax": true,
+	"runtime": true,
+	"runtime/cgo": true,
+	"runtime/debug": true,
+	"runtime/internal/atomic": true,
+	"runtime/internal/sys": true,
+	"runtime/pprof": true,
+	"runtime/pprof/internal/profile": true,
+	"runtime/race": true,
+	"runtime/trace": true,
+	"sort": true,
+	"strconv": true,
+	"strings": true,
+	"sync": true,
+	"sync/atomic": true,
+	"syscall": true,
+	"testing": true,
+	"testing/internal/testdeps": true,
+	"testing/iotest": true,
+	"testing/quick": true,
+	"text/scanner": true,
+	"text/tabwriter": true,
+	"text/template": true,
+	"text/template/parse": true,
+	"time": true,
+	"unicode": true,
+	"unicode/utf16": true,
+	"unicode/utf8": true,
+	"unsafe": true,
+}

vendor/github.com/bazelbuild/bazel-gazelle/internal/rules/BUILD

@@ -0,0 +1,34 @@
+load("@io_bazel_rules_go//go:def.bzl", "go_library")
+
+go_library(
+    name = "go_default_library",
+    srcs = [
+        "construct.go",
+        "doc.go",
+        "generator.go",
+        "sort_labels.go",
+    ],
+    importpath = "github.com/bazelbuild/bazel-gazelle/internal/rules",
+    visibility = ["//vendor/github.com/bazelbuild/bazel-gazelle:__subpackages__"],
+    deps = [
+        "//vendor/github.com/bazelbuild/bazel-gazelle/internal/config:go_default_library",
+        "//vendor/github.com/bazelbuild/bazel-gazelle/internal/label:go_default_library",
+        "//vendor/github.com/bazelbuild/bazel-gazelle/internal/packages:go_default_library",
+        "//vendor/github.com/bazelbuild/buildtools/build:go_default_library",
+        "//vendor/github.com/bazelbuild/buildtools/tables:go_default_library",
+    ],
+)
+
+filegroup(
+    name = "package-srcs",
+    srcs = glob(["**"]),
+    tags = ["automanaged"],
+    visibility = ["//visibility:private"],
+)
+
+filegroup(
+    name = "all-srcs",
+    srcs = [":package-srcs"],
+    tags = ["automanaged"],
+    visibility = ["//visibility:public"],
+)

vendor/github.com/bazelbuild/bazel-gazelle/internal/rules/construct.go

@@ -0,0 +1,217 @@
+/* Copyright 2016 The Bazel Authors. All rights reserved.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+   http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package rules
+
+import (
+	"fmt"
+	"log"
+	"reflect"
+	"sort"
+
+	"github.com/bazelbuild/bazel-gazelle/internal/config"
+	"github.com/bazelbuild/bazel-gazelle/internal/packages"
+	bf "github.com/bazelbuild/buildtools/build"
+	bt "github.com/bazelbuild/buildtools/tables"
+)
+
+// KeyValue represents a key-value pair. This gets converted into a
+// rule attribute, i.e., a Skylark keyword argument.
+type KeyValue struct {
+	Key   string
+	Value interface{}
+}
+
+// GlobValue represents a Bazel glob expression.
+type GlobValue struct {
+	Patterns []string
+	Excludes []string
+}
+
+// EmptyRule generates an empty rule with the given kind and name.
+func EmptyRule(kind, name string) *bf.CallExpr {
+	return NewRule(kind, []KeyValue{{"name", name}})
+}
+
+// NewRule generates a rule of the given kind with the given attributes.
+func NewRule(kind string, kwargs []KeyValue) *bf.CallExpr {
+	sort.Sort(byAttrName(kwargs))
+
+	var list []bf.Expr
+	for _, arg := range kwargs {
+		expr := newValue(arg.Value)
+		list = append(list, &bf.BinaryExpr{
+			X:  &bf.LiteralExpr{Token: arg.Key},
+			Op: "=",
+			Y:  expr,
+		})
+	}
+
+	return &bf.CallExpr{
+		X:    &bf.LiteralExpr{Token: kind},
+		List: list,
+	}
+}
+
+// newValue converts a Go value into the corresponding expression in Bazel BUILD file.
+func newValue(val interface{}) bf.Expr {
+	rv := reflect.ValueOf(val)
+	switch rv.Kind() {
+	case reflect.Bool:
+		tok := "False"
+		if rv.Bool() {
+			tok = "True"
+		}
+		return &bf.LiteralExpr{Token: tok}
+
+	case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64,
+		reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64:
+		return &bf.LiteralExpr{Token: fmt.Sprintf("%d", val)}
+
+	case reflect.Float32, reflect.Float64:
+		return &bf.LiteralExpr{Token: fmt.Sprintf("%f", val)}
+
+	case reflect.String:
+		return &bf.StringExpr{Value: val.(string)}
+
+	case reflect.Slice, reflect.Array:
+		var list []bf.Expr
+		for i := 0; i < rv.Len(); i++ {
+			elem := newValue(rv.Index(i).Interface())
+			list = append(list, elem)
+		}
+		return &bf.ListExpr{List: list}
+
+	case reflect.Map:
+		rkeys := rv.MapKeys()
+		sort.Sort(byString(rkeys))
+		args := make([]bf.Expr, len(rkeys))
+		for i, rk := range rkeys {
+			label := fmt.Sprintf("@%s//go/platform:%s", config.RulesGoRepoName, mapKeyString(rk))
+			k := &bf.StringExpr{Value: label}
+			v := newValue(rv.MapIndex(rk).Interface())
+			if l, ok := v.(*bf.ListExpr); ok {
+				l.ForceMultiLine = true
+			}
+			args[i] = &bf.KeyValueExpr{Key: k, Value: v}
+		}
+		args = append(args, &bf.KeyValueExpr{
+			Key:   &bf.StringExpr{Value: "//conditions:default"},
+			Value: &bf.ListExpr{},
+		})
+		sel := &bf.CallExpr{
+			X:    &bf.LiteralExpr{Token: "select"},
+			List: []bf.Expr{&bf.DictExpr{List: args, ForceMultiLine: true}},
+		}
+		return sel
+
+	case reflect.Struct:
+		switch val := val.(type) {
+		case GlobValue:
+			patternsValue := newValue(val.Patterns)
+			globArgs := []bf.Expr{patternsValue}
+			if len(val.Excludes) > 0 {
+				excludesValue := newValue(val.Excludes)
+				globArgs = append(globArgs, &bf.KeyValueExpr{
+					Key:   &bf.StringExpr{Value: "excludes"},
+					Value: excludesValue,
+				})
+			}
+			return &bf.CallExpr{
+				X:    &bf.LiteralExpr{Token: "glob"},
+				List: globArgs,
+			}
+
+		case packages.PlatformStrings:
+			var pieces []bf.Expr
+			if len(val.Generic) > 0 {
+				pieces = append(pieces, newValue(val.Generic))
+			}
+			if len(val.OS) > 0 {
+				pieces = append(pieces, newValue(val.OS))
+			}
+			if len(val.Arch) > 0 {
+				pieces = append(pieces, newValue(val.Arch))
+			}
+			if len(val.Platform) > 0 {
+				pieces = append(pieces, newValue(val.Platform))
+			}
+			if len(pieces) == 0 {
+				return &bf.ListExpr{}
+			} else if len(pieces) == 1 {
+				return pieces[0]
+			} else {
+				e := pieces[0]
+				if list, ok := e.(*bf.ListExpr); ok {
+					list.ForceMultiLine = true
+				}
+				for _, piece := range pieces[1:] {
+					e = &bf.BinaryExpr{X: e, Y: piece, Op: "+"}
+				}
+				return e
+			}
+		}
+	}
+
+	log.Panicf("type not supported: %T", val)
+	return nil
+}
+
+func mapKeyString(k reflect.Value) string {
+	switch s := k.Interface().(type) {
+	case string:
+		return s
+	case config.Platform:
+		return s.String()
+	default:
+		log.Panicf("unexpected map key: %v", k)
+		return ""
+	}
+}
+
+type byAttrName []KeyValue
+
+var _ sort.Interface = byAttrName{}
+
+func (s byAttrName) Len() int {
+	return len(s)
+}
+
+func (s byAttrName) Less(i, j int) bool {
+	if cmp := bt.NamePriority[s[i].Key] - bt.NamePriority[s[j].Key]; cmp != 0 {
+		return cmp < 0
+	}
+	return s[i].Key < s[j].Key
+}
+
+func (s byAttrName) Swap(i, j int) {
+	s[i], s[j] = s[j], s[i]
+}
+
+type byString []reflect.Value
+
+var _ sort.Interface = byString{}
+
+func (s byString) Len() int {
+	return len(s)
+}
+
+func (s byString) Less(i, j int) bool {
+	return mapKeyString(s[i]) < mapKeyString(s[j])
+}
+
+func (s byString) Swap(i, j int) {
+	s[i], s[j] = s[j], s[i]
+}

vendor/github.com/bazelbuild/bazel-gazelle/internal/rules/doc.go

@@ -0,0 +1,17 @@
+/* Copyright 2016 The Bazel Authors. All rights reserved.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+   http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+// Package rules provides Bazel rule generation for Go build targets.
+package rules

vendor/github.com/bazelbuild/bazel-gazelle/internal/rules/generator.go

@@ -0,0 +1,326 @@
+/* Copyright 2016 The Bazel Authors. All rights reserved.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+   http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package rules
+
+import (
+	"fmt"
+	"log"
+	"path"
+	"strings"
+
+	"github.com/bazelbuild/bazel-gazelle/internal/config"
+	"github.com/bazelbuild/bazel-gazelle/internal/label"
+	"github.com/bazelbuild/bazel-gazelle/internal/packages"
+	bf "github.com/bazelbuild/buildtools/build"
+)
+
+// NewGenerator returns a new instance of Generator.
+// "oldFile" is the existing build file. May be nil.
+func NewGenerator(c *config.Config, l *label.Labeler, oldFile *bf.File) *Generator {
+	shouldSetVisibility := oldFile == nil || !hasDefaultVisibility(oldFile)
+	return &Generator{c: c, l: l, shouldSetVisibility: shouldSetVisibility}
+}
+
+// Generator generates Bazel build rules for Go build targets.
+type Generator struct {
+	c                   *config.Config
+	l                   *label.Labeler
+	shouldSetVisibility bool
+}
+
+// GenerateRules generates a list of rules for targets in "pkg". It also returns
+// a list of empty rules that may be deleted from an existing file.
+func (g *Generator) GenerateRules(pkg *packages.Package) (rules []bf.Expr, empty []bf.Expr, err error) {
+	var rs []bf.Expr
+
+	protoLibName, protoRules := g.generateProto(pkg)
+	rs = append(rs, protoRules...)
+
+	libName, libRule := g.generateLib(pkg, protoLibName)
+	rs = append(rs, libRule)
+
+	rs = append(rs,
+		g.generateBin(pkg, libName),
+		g.generateTest(pkg, libName, false),
+		g.generateTest(pkg, "", true))
+
+	for _, r := range rs {
+		if isEmpty(r) {
+			empty = append(empty, r)
+		} else {
+			rules = append(rules, r)
+		}
+	}
+
+	return rules, empty, nil
+}
+
+func (g *Generator) generateProto(pkg *packages.Package) (string, []bf.Expr) {
+	if g.c.ProtoMode == config.DisableProtoMode {
+		// Don't create or delete proto rules in this mode. Any existing rules
+		// are likely hand-written.
+		return "", nil
+	}
+
+	filegroupName := config.DefaultProtosName
+	protoName := g.l.ProtoLabel(pkg.Rel, pkg.Name).Name
+	goProtoName := g.l.GoProtoLabel(pkg.Rel, pkg.Name).Name
+
+	if g.c.ProtoMode == config.LegacyProtoMode {
+		if !pkg.Proto.HasProto() {
+			return "", []bf.Expr{EmptyRule("filegroup", filegroupName)}
+		}
+		attrs := []KeyValue{
+			{Key: "name", Value: filegroupName},
+			{Key: "srcs", Value: pkg.Proto.Sources},
+		}
+		if g.shouldSetVisibility {
+			attrs = append(attrs, KeyValue{"visibility", []string{checkInternalVisibility(pkg.Rel, "//visibility:public")}})
+		}
+		return "", []bf.Expr{NewRule("filegroup", attrs)}
+	}
+
+	if !pkg.Proto.HasProto() {
+		return "", []bf.Expr{
+			EmptyRule("filegroup", filegroupName),
+			EmptyRule("proto_library", protoName),
+			EmptyRule("go_proto_library", goProtoName),
+		}
+	}
+
+	var rules []bf.Expr
+	visibility := []string{checkInternalVisibility(pkg.Rel, "//visibility:public")}
+	protoAttrs := []KeyValue{
+		{"name", protoName},
+		{"srcs", pkg.Proto.Sources},
+	}
+	if g.shouldSetVisibility {
+		protoAttrs = append(protoAttrs, KeyValue{"visibility", visibility})
+	}
+	imports := pkg.Proto.Imports
+	if !imports.IsEmpty() {
+		protoAttrs = append(protoAttrs, KeyValue{config.GazelleImportsKey, imports})
+	}
+	rules = append(rules, NewRule("proto_library", protoAttrs))
+
+	goProtoAttrs := []KeyValue{
+		{"name", goProtoName},
+		{"proto", ":" + protoName},
+		{"importpath", pkg.ImportPath},
+	}
+	if pkg.Proto.HasServices {
+		goProtoAttrs = append(goProtoAttrs, KeyValue{"compilers", []string{"@io_bazel_rules_go//proto:go_grpc"}})
+	}
+	if g.shouldSetVisibility {
+		goProtoAttrs = append(goProtoAttrs, KeyValue{"visibility", visibility})
+	}
+	if !imports.IsEmpty() {
+		goProtoAttrs = append(goProtoAttrs, KeyValue{config.GazelleImportsKey, imports})
+	}
+	rules = append(rules, NewRule("go_proto_library", goProtoAttrs))
+
+	return goProtoName, rules
+}
+
+func (g *Generator) generateBin(pkg *packages.Package, library string) bf.Expr {
+	name := g.l.BinaryLabel(pkg.Rel).Name
+	if !pkg.IsCommand() || pkg.Binary.Sources.IsEmpty() && library == "" {
+		return EmptyRule("go_binary", name)
+	}
+	visibility := checkInternalVisibility(pkg.Rel, "//visibility:public")
+	attrs := g.commonAttrs(pkg.Rel, name, visibility, pkg.Binary)
+	if library != "" {
+		attrs = append(attrs, KeyValue{"embed", []string{":" + library}})
+	}
+	return NewRule("go_binary", attrs)
+}
+
+func (g *Generator) generateLib(pkg *packages.Package, goProtoName string) (string, *bf.CallExpr) {
+	name := g.l.LibraryLabel(pkg.Rel).Name
+	if !pkg.Library.HasGo() && goProtoName == "" {
+		return "", EmptyRule("go_library", name)
+	}
+	var visibility string
+	if pkg.IsCommand() {
+		// Libraries made for a go_binary should not be exposed to the public.
+		visibility = "//visibility:private"
+	} else {
+		visibility = checkInternalVisibility(pkg.Rel, "//visibility:public")
+	}
+
+	attrs := g.commonAttrs(pkg.Rel, name, visibility, pkg.Library)
+	attrs = append(attrs, KeyValue{"importpath", pkg.ImportPath})
+	if goProtoName != "" {
+		attrs = append(attrs, KeyValue{"embed", []string{":" + goProtoName}})
+	}
+
+	rule := NewRule("go_library", attrs)
+	return name, rule
+}
+
+// hasDefaultVisibility returns whether oldFile contains a "package" rule with
+// a "default_visibility" attribute. Rules generated by Gazelle should not
+// have their own visibility attributes if this is the case.
+func hasDefaultVisibility(oldFile *bf.File) bool {
+	for _, s := range oldFile.Stmt {
+		c, ok := s.(*bf.CallExpr)
+		if !ok {
+			continue
+		}
+		r := bf.Rule{Call: c}
+		if r.Kind() == "package" && r.Attr("default_visibility") != nil {
+			return true
+		}
+	}
+	return false
+}
+
+// checkInternalVisibility overrides the given visibility if the package is
+// internal.
+func checkInternalVisibility(rel, visibility string) string {
+	if i := strings.LastIndex(rel, "/internal/"); i >= 0 {
+		visibility = fmt.Sprintf("//%s:__subpackages__", rel[:i])
+	} else if strings.HasPrefix(rel, "internal/") {
+		visibility = "//:__subpackages__"
+	}
+	return visibility
+}
+
+func (g *Generator) generateTest(pkg *packages.Package, library string, isXTest bool) bf.Expr {
+	name := g.l.TestLabel(pkg.Rel, isXTest).Name
+	target := pkg.Test
+	if isXTest {
+		target = pkg.XTest
+	}
+	if !target.HasGo() {
+		return EmptyRule("go_test", name)
+	}
+	attrs := g.commonAttrs(pkg.Rel, name, "", target)
+	if library != "" {
+		attrs = append(attrs, KeyValue{"embed", []string{":" + library}})
+	}
+	if pkg.HasTestdata {
+		glob := GlobValue{Patterns: []string{"testdata/**"}}
+		attrs = append(attrs, KeyValue{"data", glob})
+	}
+	return NewRule("go_test", attrs)
+}
+
+func (g *Generator) commonAttrs(pkgRel, name, visibility string, target packages.GoTarget) []KeyValue {
+	attrs := []KeyValue{{"name", name}}
+	if !target.Sources.IsEmpty() {
+		attrs = append(attrs, KeyValue{"srcs", target.Sources})
+	}
+	if target.Cgo {
+		attrs = append(attrs, KeyValue{"cgo", true})
+	}
+	if !target.CLinkOpts.IsEmpty() {
+		attrs = append(attrs, KeyValue{"clinkopts", g.options(target.CLinkOpts, pkgRel)})
+	}
+	if !target.COpts.IsEmpty() {
+		attrs = append(attrs, KeyValue{"copts", g.options(target.COpts, pkgRel)})
+	}
+	if g.shouldSetVisibility && visibility != "" {
+		attrs = append(attrs, KeyValue{"visibility", []string{visibility}})
+	}
+	imports := target.Imports
+	if !imports.IsEmpty() {
+		attrs = append(attrs, KeyValue{config.GazelleImportsKey, imports})
+	}
+	return attrs
+}
+
+var (
+	// shortOptPrefixes are strings that come at the beginning of an option
+	// argument that includes a path, e.g., -Ifoo/bar.
+	shortOptPrefixes = []string{"-I", "-L", "-F"}
+
+	// longOptPrefixes are separate arguments that come before a path argument,
+	// e.g., -iquote foo/bar.
+	longOptPrefixes = []string{"-I", "-L", "-F", "-iquote", "-isystem"}
+)
+
+// options transforms package-relative paths in cgo options into repository-
+// root-relative paths that Bazel can understand. For example, if a cgo file
+// in //foo declares an include flag in its copts: "-Ibar", this method
+// will transform that flag into "-Ifoo/bar".
+func (g *Generator) options(opts packages.PlatformStrings, pkgRel string) packages.PlatformStrings {
+	fixPath := func(opt string) string {
+		if strings.HasPrefix(opt, "/") {
+			return opt
+		}
+		return path.Clean(path.Join(pkgRel, opt))
+	}
+
+	fixGroups := func(groups []string) ([]string, error) {
+		fixedGroups := make([]string, len(groups))
+		for i, group := range groups {
+			opts := strings.Split(group, packages.OptSeparator)
+			fixedOpts := make([]string, len(opts))
+			isPath := false
+			for j, opt := range opts {
+				if isPath {
+					opt = fixPath(opt)
+					isPath = false
+					goto next
+				}
+
+				for _, short := range shortOptPrefixes {
+					if strings.HasPrefix(opt, short) && len(opt) > len(short) {
+						opt = short + fixPath(opt[len(short):])
+						goto next
+					}
+				}
+
+				for _, long := range longOptPrefixes {
+					if opt == long {
+						isPath = true
+						goto next
+					}
+				}
+
+			next:
+				fixedOpts[j] = escapeOption(opt)
+			}
+			fixedGroups[i] = strings.Join(fixedOpts, " ")
+		}
+
+		return fixedGroups, nil
+	}
+
+	opts, errs := opts.MapSlice(fixGroups)
+	if errs != nil {
+		log.Panicf("unexpected error when transforming options with pkg %q: %v", pkgRel, errs)
+	}
+	return opts
+}
+
+func escapeOption(opt string) string {
+	return strings.NewReplacer(
+		`\`, `\\`,
+		`'`, `\'`,
+		`"`, `\"`,
+		` `, `\ `,
+		"\t", "\\\t",
+		"\n", "\\\n",
+		"\r", "\\\r",
+	).Replace(opt)
+}
+
+func isEmpty(r bf.Expr) bool {
+	c, ok := r.(*bf.CallExpr)
+	return ok && len(c.List) == 1 // name
+}

vendor/github.com/bazelbuild/bazel-gazelle/internal/rules/sort_labels.go

@@ -0,0 +1,145 @@
+/* Copyright 2017 The Bazel Authors. All rights reserved.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+   http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package rules
+
+import (
+	"sort"
+	"strings"
+
+	bf "github.com/bazelbuild/buildtools/build"
+)
+
+var (
+	goRuleKinds = map[string]bool{
+		"cgo_library": true,
+		"go_binary":   true,
+		"go_library":  true,
+		"go_test":     true,
+	}
+	sortedAttrs = []string{"srcs", "deps"}
+)
+
+// SortLabels sorts lists of strings in "srcs" and "deps" attributes of
+// Go rules using the same order as buildifier. Buildifier also sorts string
+// lists, but not those involved with "select" expressions.
+// TODO(jayconrod): remove this when bazelbuild/buildtools#122 is fixed.
+func SortLabels(f *bf.File) {
+	for _, s := range f.Stmt {
+		c, ok := s.(*bf.CallExpr)
+		if !ok {
+			continue
+		}
+		r := bf.Rule{Call: c}
+		if !goRuleKinds[r.Kind()] {
+			continue
+		}
+		for _, key := range []string{"srcs", "deps"} {
+			attr := r.AttrDefn(key)
+			if attr == nil {
+				continue
+			}
+			bf.Walk(attr.Y, sortExprLabels)
+		}
+	}
+}
+
+func sortExprLabels(e bf.Expr, _ []bf.Expr) {
+	list, ok := e.(*bf.ListExpr)
+	if !ok || len(list.List) == 0 {
+		return
+	}
+
+	keys := make([]stringSortKey, len(list.List))
+	for i, elem := range list.List {
+		s, ok := elem.(*bf.StringExpr)
+		if !ok {
+			return // don't sort lists unless all elements are strings
+		}
+		keys[i] = makeSortKey(i, s)
+	}
+
+	before := keys[0].x.Comment().Before
+	keys[0].x.Comment().Before = nil
+	sort.Sort(byStringExpr(keys))
+	keys[0].x.Comment().Before = append(before, keys[0].x.Comment().Before...)
+	for i, k := range keys {
+		list.List[i] = k.x
+	}
+}
+
+// Code below this point is adapted from
+// github.com/bazelbuild/buildtools/build/rewrite.go
+
+// A stringSortKey records information about a single string literal to be
+// sorted. The strings are first grouped into four phases: most strings,
+// strings beginning with ":", strings beginning with "//", and strings
+// beginning with "@". The next significant part of the comparison is the list
+// of elements in the value, where elements are split at `.' and `:'. Finally
+// we compare by value and break ties by original index.
+type stringSortKey struct {
+	phase    int
+	split    []string
+	value    string
+	original int
+	x        bf.Expr
+}
+
+func makeSortKey(index int, x *bf.StringExpr) stringSortKey {
+	key := stringSortKey{
+		value:    x.Value,
+		original: index,
+		x:        x,
+	}
+
+	switch {
+	case strings.HasPrefix(x.Value, ":"):
+		key.phase = 1
+	case strings.HasPrefix(x.Value, "//"):
+		key.phase = 2
+	case strings.HasPrefix(x.Value, "@"):
+		key.phase = 3
+	}
+
+	key.split = strings.Split(strings.Replace(x.Value, ":", ".", -1), ".")
+	return key
+}
+
+// byStringExpr implements sort.Interface for a list of stringSortKey.
+type byStringExpr []stringSortKey
+
+func (x byStringExpr) Len() int      { return len(x) }
+func (x byStringExpr) Swap(i, j int) { x[i], x[j] = x[j], x[i] }
+
+func (x byStringExpr) Less(i, j int) bool {
+	xi := x[i]
+	xj := x[j]
+
+	if xi.phase != xj.phase {
+		return xi.phase < xj.phase
+	}
+	for k := 0; k < len(xi.split) && k < len(xj.split); k++ {
+		if xi.split[k] != xj.split[k] {
+			return xi.split[k] < xj.split[k]
+		}
+	}
+	if len(xi.split) != len(xj.split) {
+		return len(xi.split) < len(xj.split)
+	}
+	if xi.value != xj.value {
+		return xi.value < xj.value
+	}
+	return xi.original < xj.original
+}

vendor/github.com/bazelbuild/bazel-gazelle/internal/version/BUILD

@@ -0,0 +1,22 @@
+load("@io_bazel_rules_go//go:def.bzl", "go_library")
+
+go_library(
+    name = "go_default_library",
+    srcs = ["version.go"],
+    importpath = "github.com/bazelbuild/bazel-gazelle/internal/version",
+    visibility = ["//vendor/github.com/bazelbuild/bazel-gazelle:__subpackages__"],
+)
+
+filegroup(
+    name = "package-srcs",
+    srcs = glob(["**"]),
+    tags = ["automanaged"],
+    visibility = ["//visibility:private"],
+)
+
+filegroup(
+    name = "all-srcs",
+    srcs = [":package-srcs"],
+    tags = ["automanaged"],
+    visibility = ["//visibility:public"],
+)

vendor/github.com/bazelbuild/bazel-gazelle/internal/version/version.go

@@ -0,0 +1,72 @@
+/* Copyright 2018 The Bazel Authors. All rights reserved.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+   http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package version
+
+import (
+	"fmt"
+	"strconv"
+	"strings"
+)
+
+// Version is a tuple of non-negative integers that represents the version of
+// a software package.
+type Version []int
+
+func (v Version) String() string {
+	cstrs := make([]string, len(v))
+	for i, cn := range v {
+		cstrs[i] = strconv.Itoa(cn)
+	}
+	return strings.Join(cstrs, ".")
+}
+
+// Compare returns an integer comparing two versions lexicographically.
+func (x Version) Compare(y Version) int {
+	n := len(x)
+	if len(y) < n {
+		n = len(y)
+	}
+	for i := 0; i < n; i++ {
+		cmp := x[i] - y[i]
+		if cmp != 0 {
+			return cmp
+		}
+	}
+	return len(x) - len(y)
+}
+
+// ParseVersion parses a version of the form "12.34.56-abcd". Non-negative
+// integer components are separated by dots. An arbitrary suffix may appear
+// after '-', which is ignored.
+func ParseVersion(vs string) (Version, error) {
+	i := strings.IndexByte(vs, '-')
+	if i >= 0 {
+		vs = vs[:i]
+	}
+	cstrs := strings.Split(vs, ".")
+	v := make(Version, len(cstrs))
+	for i, cstr := range cstrs {
+		cn, err := strconv.Atoi(cstr)
+		if err != nil {
+			return nil, fmt.Errorf("could not parse version string: %q is not an integer", cstr)
+		}
+		if cn < 0 {
+			return nil, fmt.Errorf("could not parse version string: %q is negative", cstr)
+		}
+		v[i] = cn
+	}
+	return v, nil
+}

vendor/github.com/bazelbuild/bazel-gazelle/internal/wspace/BUILD

@@ -0,0 +1,22 @@
+load("@io_bazel_rules_go//go:def.bzl", "go_library")
+
+go_library(
+    name = "go_default_library",
+    srcs = ["finder.go"],
+    importpath = "github.com/bazelbuild/bazel-gazelle/internal/wspace",
+    visibility = ["//vendor/github.com/bazelbuild/bazel-gazelle:__subpackages__"],
+)
+
+filegroup(
+    name = "package-srcs",
+    srcs = glob(["**"]),
+    tags = ["automanaged"],
+    visibility = ["//visibility:private"],
+)
+
+filegroup(
+    name = "all-srcs",
+    srcs = [":package-srcs"],
+    tags = ["automanaged"],
+    visibility = ["//visibility:public"],
+)

vendor/github.com/bazelbuild/bazel-gazelle/internal/wspace/finder.go

@@ -0,0 +1,45 @@
+/* Copyright 2016 The Bazel Authors. All rights reserved.
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+   http://www.apache.org/licenses/LICENSE-2.0
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+// Package wspace provides functions to locate and modify a bazel WORKSPACE file.
+package wspace
+
+import (
+	"os"
+	"path/filepath"
+	"strings"
+)
+
+const workspaceFile = "WORKSPACE"
+
+// Find searches from the given dir and up for the WORKSPACE file
+// returning the directory containing it, or an error if none found in the tree.
+func Find(dir string) (string, error) {
+	dir, err := filepath.Abs(dir)
+	if err != nil {
+		return "", err
+	}
+
+	for {
+		_, err = os.Stat(filepath.Join(dir, workspaceFile))
+		if err == nil {
+			return dir, nil
+		}
+		if !os.IsNotExist(err) {
+			return "", err
+		}
+		if strings.HasSuffix(dir, string(os.PathSeparator)) { // stop at root dir
+			return "", os.ErrNotExist
+		}
+		dir = filepath.Dir(dir)
+	}
+}

vendor/github.com/bazelbuild/buildtools/CONTRIBUTORS

@@ -0,0 +1,15 @@
+# People who have agreed to one of the CLAs and can contribute patches.
+# The AUTHORS file lists the copyright holders; this file
+# lists people.  For example, Google employees are listed here
+# but not in AUTHORS, because Google holds the copyright.
+#
+# https://developers.google.com/open-source/cla/individual
+# https://developers.google.com/open-source/cla/corporate
+#
+# Names should be added to this file as:
+#     Name <email address>
+Paul Bethe <pbethe@google.com>
+Russ Cox <rsc@google.com>
+Laurent Le Brun <laurentlb@google.com>
+Justine Alexandra Roberts Tunney <jart@google.com>
+Nilton Volpato <nilton@google.com>

vendor/github.com/bazelbuild/buildtools/LICENSE

@@ -0,0 +1,13 @@
+Copyright 2016 Google Inc. All Rights Reserved.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.

vendor/github.com/bazelbuild/buildtools/build/BUILD

@@ -0,0 +1,32 @@
+load("@io_bazel_rules_go//go:def.bzl", "go_library")
+
+go_library(
+    name = "go_default_library",
+    srcs = [
+        "lex.go",
+        "parse.y.go",
+        "print.go",
+        "quote.go",
+        "rewrite.go",
+        "rule.go",
+        "syntax.go",
+        "walk.go",
+    ],
+    importpath = "github.com/bazelbuild/buildtools/build",
+    visibility = ["//visibility:public"],
+    deps = ["//vendor/github.com/bazelbuild/buildtools/tables:go_default_library"],
+)
+
+filegroup(
+    name = "package-srcs",
+    srcs = glob(["**"]),
+    tags = ["automanaged"],
+    visibility = ["//visibility:private"],
+)
+
+filegroup(
+    name = "all-srcs",
+    srcs = [":package-srcs"],
+    tags = ["automanaged"],
+    visibility = ["//visibility:public"],
+)

vendor/github.com/bazelbuild/buildtools/build/build_defs.bzl

@@ -0,0 +1,52 @@
+"""Provides go_yacc and genfile_check_test
+
+Copyright 2016 Google Inc. All Rights Reserved.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+ WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ See the License for the specific language governing permissions and
+ limitations under the License.
+"""
+
+_GO_YACC_TOOL = "@org_golang_x_tools//cmd/goyacc"
+
+def go_yacc(src, out, visibility=None):
+  """Runs go tool yacc -o $out $src."""
+  native.genrule(
+      name = src + ".go_yacc",
+      srcs = [src],
+      outs = [out],
+      tools = [_GO_YACC_TOOL],
+      cmd = ("export GOROOT=$$(dirname $(location " + _GO_YACC_TOOL + "))/..;" +
+             " $(location " + _GO_YACC_TOOL + ") " +
+             " -o $(location " + out + ") $(SRCS)"),
+      visibility = visibility,
+      local = 1,
+  )
+
+def genfile_check_test(src, gen):
+  """Asserts that any checked-in generated code matches regen."""
+  if not src:
+    fail("src is required", "src")
+  if not gen:
+    fail("gen is required", "gen")
+  native.genrule(
+      name = src + "_checksh",
+      outs = [src + "_check.sh"],
+      cmd = "echo 'diff $$@' > $@",
+  )
+  native.sh_test(
+      name = src + "_checkshtest",
+      size = "small",
+      srcs = [src + "_check.sh"],
+      data = [src, gen],
+      args = ["$(location " + src + ")", "$(location " + gen + ")"],
+  )
+      

vendor/github.com/bazelbuild/buildtools/build/lex.go

@@ -0,0 +1,772 @@
+/*
+Copyright 2016 Google Inc. All Rights Reserved.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+ WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ See the License for the specific language governing permissions and
+ limitations under the License.
+*/
+// Lexical scanning for BUILD file parser.
+
+package build
+
+import (
+	"bytes"
+	"fmt"
+	"strings"
+	"unicode/utf8"
+)
+
+// Parse parses the input data and returns the corresponding parse tree.
+//
+// The filename is used only for generating error messages.
+func Parse(filename string, data []byte) (*File, error) {
+	in := newInput(filename, data)
+	return in.parse()
+}
+
+// An input represents a single input file being parsed.
+type input struct {
+	// Lexing state.
+	filename  string    // name of input file, for errors
+	complete  []byte    // entire input
+	remaining []byte    // remaining input
+	token     []byte    // token being scanned
+	lastToken string    // most recently returned token, for error messages
+	pos       Position  // current input position
+	comments  []Comment // accumulated comments
+	endRule   int       // position of end of current rule
+	depth     int       // nesting of [ ] { } ( )
+
+	// Parser state.
+	file       *File // returned top-level syntax tree
+	parseError error // error encountered during parsing
+
+	// Comment assignment state.
+	pre  []Expr // all expressions, in preorder traversal
+	post []Expr // all expressions, in postorder traversal
+}
+
+func newInput(filename string, data []byte) *input {
+	return &input{
+		filename:  filename,
+		complete:  data,
+		remaining: data,
+		pos:       Position{Line: 1, LineRune: 1, Byte: 0},
+	}
+}
+
+// parse parses the input file.
+func (in *input) parse() (f *File, err error) {
+	// The parser panics for both routine errors like syntax errors
+	// and for programmer bugs like array index errors.
+	// Turn both into error returns. Catching bug panics is
+	// especially important when processing many files.
+	defer func() {
+		if e := recover(); e != nil {
+			if e == in.parseError {
+				err = in.parseError
+			} else {
+				err = fmt.Errorf("%s:%d:%d: internal error: %v", in.filename, in.pos.Line, in.pos.LineRune, e)
+			}
+		}
+	}()
+
+	// Invoke the parser generated from parse.y.
+	yyParse(in)
+	if in.parseError != nil {
+		return nil, in.parseError
+	}
+	in.file.Path = in.filename
+
+	// Assign comments to nearby syntax.
+	in.assignComments()
+
+	return in.file, nil
+}
+
+// Error is called to report an error.
+// When called by the generated code s is always "syntax error".
+// Error does not return: it panics.
+func (in *input) Error(s string) {
+	if s == "syntax error" && in.lastToken != "" {
+		s += " near " + in.lastToken
+	}
+	in.parseError = fmt.Errorf("%s:%d:%d: %v", in.filename, in.pos.Line, in.pos.LineRune, s)
+	panic(in.parseError)
+}
+
+// eof reports whether the input has reached end of file.
+func (in *input) eof() bool {
+	return len(in.remaining) == 0
+}
+
+// peekRune returns the next rune in the input without consuming it.
+func (in *input) peekRune() int {
+	if len(in.remaining) == 0 {
+		return 0
+	}
+	r, _ := utf8.DecodeRune(in.remaining)
+	return int(r)
+}
+
+// readRune consumes and returns the next rune in the input.
+func (in *input) readRune() int {
+	if len(in.remaining) == 0 {
+		in.Error("internal lexer error: readRune at EOF")
+	}
+	r, size := utf8.DecodeRune(in.remaining)
+	in.remaining = in.remaining[size:]
+	if r == '\n' {
+		in.pos.Line++
+		in.pos.LineRune = 1
+	} else {
+		in.pos.LineRune++
+	}
+	in.pos.Byte += size
+	return int(r)
+}
+
+// startToken marks the beginning of the next input token.
+// It must be followed by a call to endToken, once the token has
+// been consumed using readRune.
+func (in *input) startToken(val *yySymType) {
+	in.token = in.remaining
+	val.tok = ""
+	val.pos = in.pos
+}
+
+// yySymType (used in the next few functions) is defined by the
+// generated parser. It is a struct containing all the fields listed
+// in parse.y's %union [sic] section.
+
+// endToken marks the end of an input token.
+// It records the actual token string in val.tok if the caller
+// has not done that already.
+func (in *input) endToken(val *yySymType) {
+	if val.tok == "" {
+		tok := string(in.token[:len(in.token)-len(in.remaining)])
+		val.tok = tok
+		in.lastToken = val.tok
+	}
+}
+
+// Lex is called from the generated parser to obtain the next input token.
+// It returns the token value (either a rune like '+' or a symbolic token _FOR)
+// and sets val to the data associated with the token.
+//
+// For all our input tokens, the associated data is
+// val.Pos (the position where the token begins)
+// and val.Token (the input string corresponding to the token).
+func (in *input) Lex(val *yySymType) int {
+	// Skip past spaces, stopping at non-space or EOF.
+	countNL := 0 // number of newlines we've skipped past
+	for !in.eof() {
+		// The parser does not track indentation, because for the most part
+		// BUILD expressions don't care about how they are indented.
+		// However, we do need to be able to distinguish
+		//
+		//	x = y[0]
+		//
+		// from the occasional
+		//
+		//	x = y
+		//	[0]
+		//
+		// To handle this one case, when we reach the beginning of a
+		// top-level BUILD expression, we scan forward to see where
+		// it should end and record the number of input bytes remaining
+		// at that endpoint. When we reach that point in the input, we
+		// insert an implicit semicolon to force the two expressions
+		// to stay separate.
+		//
+		if in.endRule != 0 && len(in.remaining) == in.endRule {
+			in.endRule = 0
+			in.lastToken = "implicit ;"
+			val.tok = ";"
+			return ';'
+		}
+
+		// Skip over spaces. Count newlines so we can give the parser
+		// information about where top-level blank lines are,
+		// for top-level comment assignment.
+		c := in.peekRune()
+		if c == ' ' || c == '\t' || c == '\r' || c == '\n' {
+			if c == '\n' && in.endRule == 0 {
+				// Not in a rule. Tell parser about top-level blank line.
+				in.startToken(val)
+				in.readRune()
+				in.endToken(val)
+				return '\n'
+			}
+			if c == '\n' {
+				countNL++
+			}
+			in.readRune()
+			continue
+		}
+
+		// Comment runs to end of line.
+		if c == '#' {
+			// Is this comment the only thing on its line?
+			// Find the last \n before this # and see if it's all
+			// spaces from there to here.
+			// If it's a suffix comment but the last non-space symbol before
+			// it is one of (, [, or {, treat it as a line comment that should be
+			// put inside the corresponding block.
+			i := bytes.LastIndex(in.complete[:in.pos.Byte], []byte("\n"))
+			prefix := bytes.TrimSpace(in.complete[i+1 : in.pos.Byte])
+			isSuffix := true
+			if len(prefix) == 0 ||
+				prefix[len(prefix)-1] == '[' ||
+				prefix[len(prefix)-1] == '(' ||
+				prefix[len(prefix)-1] == '{' {
+				isSuffix = false
+			}
+
+			// Consume comment.
+			in.startToken(val)
+			for len(in.remaining) > 0 && in.readRune() != '\n' {
+			}
+			in.endToken(val)
+
+			val.tok = strings.TrimRight(val.tok, "\n")
+			in.lastToken = "comment"
+
+			// If we are at top level (not in a rule), hand the comment to
+			// the parser as a _COMMENT token. The grammar is written
+			// to handle top-level comments itself.
+			if in.endRule == 0 {
+				// Not in a rule. Tell parser about top-level comment.
+				return _COMMENT
+			}
+
+			// Otherwise, save comment for later attachment to syntax tree.
+			if countNL > 1 {
+				in.comments = append(in.comments, Comment{val.pos, "", false})
+			}
+			in.comments = append(in.comments, Comment{val.pos, val.tok, isSuffix})
+			countNL = 1
+			continue
+		}
+
+		if c == '\\' && len(in.remaining) >= 2 && in.remaining[1] == '\n' {
+			// We can ignore a trailing \ at end of line.
+			in.readRune()
+			continue
+		}
+
+		// Found non-space non-comment.
+		break
+	}
+
+	// Found the beginning of the next token.
+	in.startToken(val)
+	defer in.endToken(val)
+
+	// End of file.
+	if in.eof() {
+		in.lastToken = "EOF"
+		return _EOF
+	}
+
+	// If endRule is 0, we need to recompute where the end
+	// of the next rule (Python expression) is, so that we can
+	// generate a virtual end-of-rule semicolon (see above).
+	if in.endRule == 0 {
+		in.endRule = len(in.skipPython(in.remaining))
+		if in.endRule == 0 {
+			// skipPython got confused.
+			// No more virtual semicolons.
+			in.endRule = -1
+		}
+	}
+
+	// Punctuation tokens.
+	switch c := in.peekRune(); c {
+	case '[', '(', '{':
+		in.depth++
+		in.readRune()
+		return c
+
+	case ']', ')', '}':
+		in.depth--
+		in.readRune()
+		return c
+
+	case '.', '-', '%', ':', ';', ',', '/', '*': // single-char tokens
+		in.readRune()
+		return c
+
+	case '<', '>', '=', '!', '+': // possibly followed by =
+		in.readRune()
+		if in.peekRune() == '=' {
+			in.readRune()
+			switch c {
+			case '<':
+				return _LE
+			case '>':
+				return _GE
+			case '=':
+				return _EQ
+			case '!':
+				return _NE
+			case '+':
+				return _ADDEQ
+			}
+		}
+		return c
+
+	case 'r': // possible beginning of raw quoted string
+		if len(in.remaining) < 2 || in.remaining[1] != '"' && in.remaining[1] != '\'' {
+			break
+		}
+		in.readRune()
+		c = in.peekRune()
+		fallthrough
+
+	case '"', '\'': // quoted string
+		quote := c
+		if len(in.remaining) >= 3 && in.remaining[0] == byte(quote) && in.remaining[1] == byte(quote) && in.remaining[2] == byte(quote) {
+			// Triple-quoted string.
+			in.readRune()
+			in.readRune()
+			in.readRune()
+			var c1, c2, c3 int
+			for {
+				if in.eof() {
+					in.pos = val.pos
+					in.Error("unexpected EOF in string")
+				}
+				c1, c2, c3 = c2, c3, in.readRune()
+				if c1 == quote && c2 == quote && c3 == quote {
+					break
+				}
+				if c3 == '\\' {
+					if in.eof() {
+						in.pos = val.pos
+						in.Error("unexpected EOF in string")
+					}
+					in.readRune()
+				}
+			}
+		} else {
+			in.readRune()
+			for {
+				if in.eof() {
+					in.pos = val.pos
+					in.Error("unexpected EOF in string")
+				}
+				if in.peekRune() == '\n' {
+					in.Error("unexpected newline in string")
+				}
+				c := in.readRune()
+				if c == quote {
+					break
+				}
+				if c == '\\' {
+					if in.eof() {
+						in.pos = val.pos
+						in.Error("unexpected EOF in string")
+					}
+					in.readRune()
+				}
+			}
+		}
+		in.endToken(val)
+		s, triple, err := unquote(val.tok)
+		if err != nil {
+			in.Error(fmt.Sprint(err))
+		}
+		val.str = s
+		val.triple = triple
+		return _STRING
+	}
+
+	// Checked all punctuation. Must be identifier token.
+	if c := in.peekRune(); !isIdent(c) {
+		in.Error(fmt.Sprintf("unexpected input character %#q", c))
+	}
+
+	// Look for raw Python block (class, def, if, etc at beginning of line) and pass through.
+	if in.depth == 0 && in.pos.LineRune == 1 && hasPythonPrefix(in.remaining) {
+		// Find end of Python block and advance input beyond it.
+		// Have to loop calling readRune in order to maintain line number info.
+		rest := in.skipPython(in.remaining)
+		for len(in.remaining) > len(rest) {
+			in.readRune()
+		}
+		return _PYTHON
+	}
+
+	// Scan over alphanumeric identifier.
+	for {
+		c := in.peekRune()
+		if !isIdent(c) {
+			break
+		}
+		in.readRune()
+	}
+
+	// Call endToken to set val.tok to identifier we just scanned,
+	// so we can look to see if val.tok is a keyword.
+	in.endToken(val)
+	if k := keywordToken[val.tok]; k != 0 {
+		return k
+	}
+
+	return _IDENT
+}
+
+// isIdent reports whether c is an identifier rune.
+// We treat all non-ASCII runes as identifier runes.
+func isIdent(c int) bool {
+	return '0' <= c && c <= '9' ||
+		'A' <= c && c <= 'Z' ||
+		'a' <= c && c <= 'z' ||
+		c == '_' ||
+		c >= 0x80
+}
+
+// keywordToken records the special tokens for
+// strings that should not be treated as ordinary identifiers.
+var keywordToken = map[string]int{
+	"and":    _AND,
+	"for":    _FOR,
+	"if":     _IF,
+	"else":   _ELSE,
+	"in":     _IN,
+	"is":     _IS,
+	"lambda": _LAMBDA,
+	"not":    _NOT,
+	"or":     _OR,
+}
+
+// Python scanning.
+// About 1% of BUILD files embed arbitrary Python into the file.
+// We do not attempt to parse it. Instead, we lex just enough to scan
+// beyond it, treating the Python block as an unintepreted blob.
+
+// hasPythonPrefix reports whether p begins with a keyword that would
+// introduce an uninterpreted Python block.
+func hasPythonPrefix(p []byte) bool {
+	for _, pre := range prefixes {
+		if hasPrefixSpace(p, pre) {
+			return true
+		}
+	}
+	return false
+}
+
+// These keywords introduce uninterpreted Python blocks.
+var prefixes = []string{
+	"assert",
+	"class",
+	"def",
+	"del",
+	"for",
+	"if",
+	"try",
+}
+
+// hasPrefixSpace reports whether p begins with pre followed by a space or colon.
+func hasPrefixSpace(p []byte, pre string) bool {
+	if len(p) <= len(pre) || p[len(pre)] != ' ' && p[len(pre)] != '\t' && p[len(pre)] != ':' {
+		return false
+	}
+	for i := range pre {
+		if p[i] != pre[i] {
+			return false
+		}
+	}
+	return true
+}
+
+func isBlankOrComment(b []byte) bool {
+	for _, c := range b {
+		if c == '#' || c == '\n' {
+			return true
+		}
+		if c != ' ' && c != '\t' && c != '\r' {
+			return false
+		}
+	}
+	return true
+}
+
+// hasPythonContinuation reports whether p begins with a keyword that
+// continues an uninterpreted Python block.
+func hasPythonContinuation(p []byte) bool {
+	for _, pre := range continuations {
+		if hasPrefixSpace(p, pre) {
+			return true
+		}
+	}
+	return false
+}
+
+// These keywords continue uninterpreted Python blocks.
+var continuations = []string{
+	"except",
+	"else",
+}
+
+// skipPython returns the data remaining after the uninterpreted
+// Python block beginning at p. It does not advance the input position.
+// (The only reason for the input receiver is to be able to call in.Error.)
+func (in *input) skipPython(p []byte) []byte {
+	quote := byte(0)     // if non-zero, the kind of quote we're in
+	tripleQuote := false // if true, the quote is a triple quote
+	depth := 0           // nesting depth for ( ) [ ] { }
+	var rest []byte      // data after the Python block
+
+	// Scan over input one byte at a time until we find
+	// an unindented, non-blank, non-comment line
+	// outside quoted strings and brackets.
+	for i := 0; i < len(p); i++ {
+		c := p[i]
+		if quote != 0 && c == quote && !tripleQuote {
+			quote = 0
+			continue
+		}
+		if quote != 0 && c == quote && tripleQuote && i+2 < len(p) && p[i+1] == quote && p[i+2] == quote {
+			i += 2
+			quote = 0
+			tripleQuote = false
+			continue
+		}
+		if quote != 0 {
+			if c == '\\' {
+				i++ // skip escaped char
+			}
+			continue
+		}
+		if c == '\'' || c == '"' {
+			if i+2 < len(p) && p[i+1] == c && p[i+2] == c {
+				quote = c
+				tripleQuote = true
+				i += 2
+				continue
+			}
+			quote = c
+			continue
+		}
+
+		if depth == 0 && i > 0 && p[i-1] == '\n' && (i < 2 || p[i-2] != '\\') {
+			// Possible stopping point. Save the earliest one we find.
+			if rest == nil {
+				rest = p[i:]
+			}
+
+			if !isBlankOrComment(p[i:]) {
+				if !hasPythonContinuation(p[i:]) && c != ' ' && c != '\t' {
+					// Yes, stop here.
+					break
+				}
+				// Not a stopping point after all.
+				rest = nil
+			}
+		}
+
+		switch c {
+		case '#':
+			// Skip comment.
+			for i < len(p) && p[i] != '\n' {
+				i++
+			}
+
+		case '(', '[', '{':
+			depth++
+
+		case ')', ']', '}':
+			depth--
+		}
+	}
+	if quote != 0 {
+		in.Error("EOF scanning Python quoted string")
+	}
+	return rest
+}
+
+// Comment assignment.
+// We build two lists of all subexpressions, preorder and postorder.
+// The preorder list is ordered by start location, with outer expressions first.
+// The postorder list is ordered by end location, with outer expressions last.
+// We use the preorder list to assign each whole-line comment to the syntax
+// immediately following it, and we use the postorder list to assign each
+// end-of-line comment to the syntax immediately preceding it.
+
+// order walks the expression adding it and its subexpressions to the
+// preorder and postorder lists.
+func (in *input) order(v Expr) {
+	if v != nil {
+		in.pre = append(in.pre, v)
+	}
+	switch v := v.(type) {
+	default:
+		panic(fmt.Errorf("order: unexpected type %T", v))
+	case nil:
+		// nothing
+	case *End:
+		// nothing
+	case *File:
+		for _, stmt := range v.Stmt {
+			in.order(stmt)
+		}
+	case *CommentBlock:
+		// nothing
+	case *CallExpr:
+		in.order(v.X)
+		for _, x := range v.List {
+			in.order(x)
+		}
+		in.order(&v.End)
+	case *PythonBlock:
+		// nothing
+	case *LiteralExpr:
+		// nothing
+	case *StringExpr:
+		// nothing
+	case *DotExpr:
+		in.order(v.X)
+	case *ListExpr:
+		for _, x := range v.List {
+			in.order(x)
+		}
+		in.order(&v.End)
+	case *ListForExpr:
+		in.order(v.X)
+		for _, c := range v.For {
+			in.order(c)
+		}
+		in.order(&v.End)
+	case *SetExpr:
+		for _, x := range v.List {
+			in.order(x)
+		}
+		in.order(&v.End)
+	case *ForClauseWithIfClausesOpt:
+		in.order(v.For)
+		for _, c := range v.Ifs {
+			in.order(c)
+		}
+	case *ForClause:
+		for _, name := range v.Var {
+			in.order(name)
+		}
+		in.order(v.Expr)
+	case *IfClause:
+		in.order(v.Cond)
+	case *KeyValueExpr:
+		in.order(v.Key)
+		in.order(v.Value)
+	case *DictExpr:
+		for _, x := range v.List {
+			in.order(x)
+		}
+		in.order(&v.End)
+	case *TupleExpr:
+		for _, x := range v.List {
+			in.order(x)
+		}
+		in.order(&v.End)
+	case *UnaryExpr:
+		in.order(v.X)
+	case *BinaryExpr:
+		in.order(v.X)
+		in.order(v.Y)
+	case *ConditionalExpr:
+		in.order(v.Then)
+		in.order(v.Test)
+		in.order(v.Else)
+	case *ParenExpr:
+		in.order(v.X)
+		in.order(&v.End)
+	case *SliceExpr:
+		in.order(v.X)
+		in.order(v.Y)
+		in.order(v.Z)
+	case *IndexExpr:
+		in.order(v.X)
+		in.order(v.Y)
+	case *LambdaExpr:
+		for _, name := range v.Var {
+			in.order(name)
+		}
+		in.order(v.Expr)
+	}
+	if v != nil {
+		in.post = append(in.post, v)
+	}
+}
+
+// assignComments attaches comments to nearby syntax.
+func (in *input) assignComments() {
+	// Generate preorder and postorder lists.
+	in.order(in.file)
+
+	// Split into whole-line comments and suffix comments.
+	var line, suffix []Comment
+	for _, com := range in.comments {
+		if com.Suffix {
+			suffix = append(suffix, com)
+		} else {
+			line = append(line, com)
+		}
+	}
+
+	// Assign line comments to syntax immediately following.
+	for _, x := range in.pre {
+		start, _ := x.Span()
+		xcom := x.Comment()
+		for len(line) > 0 && start.Byte >= line[0].Start.Byte {
+			xcom.Before = append(xcom.Before, line[0])
+			line = line[1:]
+		}
+	}
+
+	// Remaining line comments go at end of file.
+	in.file.After = append(in.file.After, line...)
+
+	// Assign suffix comments to syntax immediately before.
+	for i := len(in.post) - 1; i >= 0; i-- {
+		x := in.post[i]
+
+		// Do not assign suffix comments to file
+		switch x.(type) {
+		case *File:
+			continue
+		}
+
+		_, end := x.Span()
+		xcom := x.Comment()
+		for len(suffix) > 0 && end.Byte <= suffix[len(suffix)-1].Start.Byte {
+			xcom.Suffix = append(xcom.Suffix, suffix[len(suffix)-1])
+			suffix = suffix[:len(suffix)-1]
+		}
+	}
+
+	// We assigned suffix comments in reverse.
+	// If multiple suffix comments were appended to the same
+	// expression node, they are now in reverse. Fix that.
+	for _, x := range in.post {
+		reverseComments(x.Comment().Suffix)
+	}
+
+	// Remaining suffix comments go at beginning of file.
+	in.file.Before = append(in.file.Before, suffix...)
+}
+
+// reverseComments reverses the []Comment list.
+func reverseComments(list []Comment) {
+	for i, j := 0, len(list)-1; i < j; i, j = i+1, j-1 {
+		list[i], list[j] = list[j], list[i]
+	}
+}

vendor/github.com/bazelbuild/buildtools/build/parse.y

@@ -0,0 +1,684 @@
+// BUILD file parser.
+
+// This is a yacc grammar. Its lexer is in lex.go.
+//
+// For a good introduction to writing yacc grammars, see
+// Kernighan and Pike's book The Unix Programming Environment.
+//
+// The definitive yacc manual is
+// Stephen C. Johnson and Ravi Sethi, "Yacc: A Parser Generator",
+// online at http://plan9.bell-labs.com/sys/doc/yacc.pdf.
+
+%{
+package build
+%}
+
+// The generated parser puts these fields in a struct named yySymType.
+// (The name %union is historical, but it is inaccurate for Go.)
+%union {
+	// input tokens
+	tok       string     // raw input syntax
+	str       string     // decoding of quoted string
+	pos       Position   // position of token
+	triple    bool       // was string triple quoted?
+
+	// partial syntax trees
+	expr      Expr
+	exprs     []Expr
+	forc      *ForClause
+	ifs       []*IfClause
+	forifs    *ForClauseWithIfClausesOpt
+	forsifs   []*ForClauseWithIfClausesOpt
+	string    *StringExpr
+	strings   []*StringExpr
+
+	// supporting information
+	comma     Position   // position of trailing comma in list, if present
+	lastRule  Expr  // most recent rule, to attach line comments to
+}
+
+// These declarations set the type for a $ reference ($$, $1, $2, ...)
+// based on the kind of symbol it refers to. Other fields can be referred
+// to explicitly, as in $<tok>1.
+//
+// %token is for input tokens generated by the lexer.
+// %type is for higher-level grammar rules defined here.
+//
+// It is possible to put multiple tokens per line, but it is easier to
+// keep ordered using a sparser one-per-line list.
+
+%token	<pos>	'%'
+%token	<pos>	'('
+%token	<pos>	')'
+%token	<pos>	'*'
+%token	<pos>	'+'
+%token	<pos>	','
+%token	<pos>	'-'
+%token	<pos>	'.'
+%token	<pos>	'/'
+%token	<pos>	':'
+%token	<pos>	'<'
+%token	<pos>	'='
+%token	<pos>	'>'
+%token	<pos>	'['
+%token	<pos>	']'
+%token	<pos>	'{'
+%token	<pos>	'}'
+
+// By convention, yacc token names are all caps.
+// However, we do not want to export them from the Go package
+// we are creating, so prefix them all with underscores.
+
+%token	<pos>	_ADDEQ   // operator +=
+%token	<pos>	_AND     // keyword and
+%token	<pos>	_COMMENT // top-level # comment
+%token	<pos>	_EOF     // end of file
+%token	<pos>	_EQ      // operator ==
+%token	<pos>	_FOR     // keyword for
+%token	<pos>	_GE      // operator >=
+%token	<pos>	_IDENT   // non-keyword identifier or number
+%token	<pos>	_IF      // keyword if
+%token	<pos>	_ELSE    // keyword else
+%token	<pos>	_IN      // keyword in
+%token	<pos>	_IS      // keyword is
+%token	<pos>	_LAMBDA  // keyword lambda
+%token	<pos>	_LE      // operator <=
+%token	<pos>	_NE      // operator !=
+%token	<pos>	_NOT     // keyword not
+%token	<pos>	_OR      // keyword or
+%token	<pos>	_PYTHON  // uninterpreted Python block
+%token	<pos>	_STRING  // quoted string
+
+%type	<pos>		comma_opt
+%type	<expr>		expr
+%type	<expr>		expr_opt
+%type	<exprs>		exprs
+%type	<exprs>		exprs_opt
+%type	<forc>		for_clause
+%type	<forifs>	for_clause_with_if_clauses_opt
+%type	<forsifs>	for_clauses_with_if_clauses_opt
+%type	<expr>		ident
+%type	<exprs>		idents
+%type	<ifs>		if_clauses_opt
+%type	<exprs>		stmts
+%type	<expr>		stmt
+%type	<expr>		keyvalue
+%type	<exprs>		keyvalues
+%type	<exprs>		keyvalues_no_comma
+%type	<string>	string
+%type	<strings>	strings
+
+// Operator precedence.
+// Operators listed lower in the table bind tighter.
+
+// We tag rules with this fake, low precedence to indicate
+// that when the rule is involved in a shift/reduce
+// conflict, we prefer that the parser shift (try for a longer parse).
+// Shifting is the default resolution anyway, but stating it explicitly
+// silences yacc's warning for that specific case.
+%left	ShiftInstead
+
+%left	'\n'
+%left	_ASSERT
+// '=' and '+=' have the lowest precedence
+// e.g. "x = a if c > 0 else 'bar'"
+// followed by
+// 'if' and 'else' which have lower precedence than all other operators.
+// e.g. "a, b if c > 0 else 'foo'" is either a tuple of (a,b) or 'foo'
+// and not a tuple of "(a, (b if ... ))"
+%left	'=' _ADDEQ
+%left   _IF _ELSE
+%left	','
+%left	':'
+%left	_IN _NOT _IS
+%left	_OR
+%left	_AND
+%left	'<' '>' _EQ _NE _LE _GE
+%left	'+' '-'
+%left	'*' '/' '%'
+%left	'.' '[' '('
+%right  _UNARY
+%left	_STRING
+
+%%
+
+// Grammar rules.
+//
+// A note on names: if foo is a rule, then foos is a sequence of foos
+// (with interleaved commas or other syntax as appropriate)
+// and foo_opt is an optional foo.
+
+file:
+	stmts _EOF
+	{
+		yylex.(*input).file = &File{Stmt: $1}
+		return 0
+	}
+
+stmts:
+	{
+		$$ = nil
+		$<lastRule>$ = nil
+	}
+|	stmts stmt comma_opt semi_opt
+	{
+		// If this statement follows a comment block,
+		// attach the comments to the statement.
+		if cb, ok := $<lastRule>1.(*CommentBlock); ok {
+			$$ = $1
+			$$[len($1)-1] = $2
+			$2.Comment().Before = cb.After
+			$<lastRule>$ = $2
+			break
+		}
+
+		// Otherwise add to list.
+		$$ = append($1, $2)
+		$<lastRule>$ = $2
+
+		// Consider this input:
+		//
+		//	foo()
+		//	# bar
+		//	baz()
+		//
+		// If we've just parsed baz(), the # bar is attached to
+		// foo() as an After comment. Make it a Before comment
+		// for baz() instead.
+		if x := $<lastRule>1; x != nil {
+			com := x.Comment()
+			$2.Comment().Before = com.After
+			com.After = nil
+		}
+	}
+|	stmts '\n'
+	{
+		// Blank line; sever last rule from future comments.
+		$$ = $1
+		$<lastRule>$ = nil
+	}
+|	stmts _COMMENT
+	{
+		$$ = $1
+		$<lastRule>$ = $<lastRule>1
+		if $<lastRule>$ == nil {
+			cb := &CommentBlock{Start: $2}
+			$$ = append($$, cb)
+			$<lastRule>$ = cb
+		}
+		com := $<lastRule>$.Comment()
+		com.After = append(com.After, Comment{Start: $2, Token: $<tok>2})
+	}
+
+stmt:
+	expr %prec ShiftInstead
+|	_PYTHON
+	{
+		$$ = &PythonBlock{Start: $1, Token: $<tok>1}
+	}
+
+semi_opt:
+|	semi_opt ';'
+
+expr:
+	ident
+|	strings %prec ShiftInstead
+	{
+		if len($1) == 1 {
+			$$ = $1[0]
+			break
+		}
+
+		$$ = $1[0]
+		for _, x := range $1[1:] {
+			_, end := $$.Span()
+			$$ = binary($$, end, "+", x)
+		}
+	}
+|	'[' exprs_opt ']'
+	{
+		$$ = &ListExpr{
+			Start: $1,
+			List: $2,
+			Comma: $<comma>2,
+			End: End{Pos: $3},
+			ForceMultiLine: forceMultiLine($1, $2, $3),
+		}
+	}
+|	'[' expr for_clauses_with_if_clauses_opt ']'
+	{
+		exprStart, _ := $2.Span()
+		$$ = &ListForExpr{
+			Brack: "[]",
+			Start: $1,
+			X: $2,
+			For: $3,
+			End: End{Pos: $4},
+			ForceMultiLine: $1.Line != exprStart.Line,
+		}
+	}
+|	'(' expr for_clauses_with_if_clauses_opt ')'
+	{
+		exprStart, _ := $2.Span()
+		$$ = &ListForExpr{
+			Brack: "()",
+			Start: $1,
+			X: $2,
+			For: $3,
+			End: End{Pos: $4},
+			ForceMultiLine: $1.Line != exprStart.Line,
+		}
+	}
+|	'{' keyvalue for_clauses_with_if_clauses_opt '}'
+	{
+		exprStart, _ := $2.Span()
+		$$ = &ListForExpr{
+			Brack: "{}",
+			Start: $1,
+			X: $2,
+			For: $3,
+			End: End{Pos: $4},
+			ForceMultiLine: $1.Line != exprStart.Line,
+		}
+	}
+|	'{' keyvalues '}'
+	{
+		$$ = &DictExpr{
+			Start: $1,
+			List: $2,
+			Comma: $<comma>2,
+			End: End{Pos: $3},
+			ForceMultiLine: forceMultiLine($1, $2, $3),
+		}
+	}
+|	'{' exprs_opt '}'
+	{
+		$$ = &SetExpr{
+			Start: $1,
+			List: $2,
+			Comma: $<comma>2,
+			End: End{Pos: $3},
+			ForceMultiLine: forceMultiLine($1, $2, $3),
+		}
+	}
+|	'(' exprs_opt ')'
+	{
+		if len($2) == 1 && $<comma>2.Line == 0 {
+			// Just a parenthesized expression, not a tuple.
+			$$ = &ParenExpr{
+				Start: $1,
+				X: $2[0],
+				End: End{Pos: $3},
+				ForceMultiLine: forceMultiLine($1, $2, $3),
+			}
+		} else {
+			$$ = &TupleExpr{
+				Start: $1,
+				List: $2,
+				Comma: $<comma>2,
+				End: End{Pos: $3},
+				ForceCompact: forceCompact($1, $2, $3),
+				ForceMultiLine: forceMultiLine($1, $2, $3),
+			}
+		}
+	}
+|	expr '.' _IDENT
+	{
+		$$ = &DotExpr{
+			X: $1,
+			Dot: $2,
+			NamePos: $3,
+			Name: $<tok>3,
+		}
+	}
+|	expr '(' exprs_opt ')'
+	{
+		$$ = &CallExpr{
+			X: $1,
+			ListStart: $2,
+			List: $3,
+			End: End{Pos: $4},
+			ForceCompact: forceCompact($2, $3, $4),
+			ForceMultiLine: forceMultiLine($2, $3, $4),
+		}
+	}
+|	expr '(' expr for_clauses_with_if_clauses_opt ')'
+	{
+		$$ = &CallExpr{
+			X: $1,
+			ListStart: $2,
+			List: []Expr{
+				&ListForExpr{
+					Brack: "",
+					Start: $2,
+					X: $3,
+					For: $4,
+					End: End{Pos: $5},
+				},
+			},
+			End: End{Pos: $5},
+		}
+	}
+|	expr '[' expr ']'
+	{
+		$$ = &IndexExpr{
+			X: $1,
+			IndexStart: $2,
+			Y: $3,
+			End: $4,
+		}
+	}
+|	expr '[' expr_opt ':' expr_opt ']'
+	{
+		$$ = &SliceExpr{
+			X: $1,
+			SliceStart: $2,
+			Y: $3,
+			Colon: $4,
+			Z: $5,
+			End: $6,
+		}
+	}
+|	_LAMBDA exprs ':' expr
+	{
+		$$ = &LambdaExpr{
+			Lambda: $1,
+			Var: $2,
+			Colon: $3,
+			Expr: $4,
+		}
+	}
+|	'-' expr  %prec _UNARY { $$ = unary($1, $<tok>1, $2) }
+|	_NOT expr %prec _UNARY { $$ = unary($1, $<tok>1, $2) }
+|	'*' expr  %prec _UNARY { $$ = unary($1, $<tok>1, $2) }
+|	expr '*' expr      { $$ = binary($1, $2, $<tok>2, $3) }
+|	expr '%' expr      { $$ = binary($1, $2, $<tok>2, $3) }
+|	expr '/' expr      { $$ = binary($1, $2, $<tok>2, $3) }
+|	expr '+' expr      { $$ = binary($1, $2, $<tok>2, $3) }
+|	expr '-' expr      { $$ = binary($1, $2, $<tok>2, $3) }
+|	expr '<' expr      { $$ = binary($1, $2, $<tok>2, $3) }
+|	expr '>' expr      { $$ = binary($1, $2, $<tok>2, $3) }
+|	expr _EQ expr      { $$ = binary($1, $2, $<tok>2, $3) }
+|	expr _LE expr      { $$ = binary($1, $2, $<tok>2, $3) }
+|	expr _NE expr      { $$ = binary($1, $2, $<tok>2, $3) }
+|	expr _GE expr      { $$ = binary($1, $2, $<tok>2, $3) }
+|	expr '=' expr      { $$ = binary($1, $2, $<tok>2, $3) }
+|	expr _ADDEQ expr   { $$ = binary($1, $2, $<tok>2, $3) }
+|	expr _IN expr      { $$ = binary($1, $2, $<tok>2, $3) }
+|	expr _NOT _IN expr { $$ = binary($1, $2, "not in", $4) }
+|	expr _OR expr      { $$ = binary($1, $2, $<tok>2, $3) }
+|	expr _AND expr     { $$ = binary($1, $2, $<tok>2, $3) }
+|	expr _IS expr
+	{
+		if b, ok := $3.(*UnaryExpr); ok && b.Op == "not" {
+			$$ = binary($1, $2, "is not", b.X)
+		} else {
+			$$ = binary($1, $2, $<tok>2, $3)
+		}
+	}
+|       expr _IF expr _ELSE expr
+	{
+                $$ = &ConditionalExpr{
+                        Then: $1,
+                        IfStart: $2,
+                        Test: $3,
+                        ElseStart: $4,
+                        Else: $5,
+                }
+	}
+
+expr_opt:
+	{
+		$$ = nil
+	}
+|	expr
+
+// comma_opt is an optional comma. If the comma is present,
+// the rule's value is the position of the comma. Otherwise
+// the rule's value is the zero position. Tracking this
+// lets us distinguish (x) and (x,).
+comma_opt:
+	{
+		$$ = Position{}
+	}
+|	','
+
+keyvalue:
+	expr ':' expr  {
+		$$ = &KeyValueExpr{
+			Key: $1,
+			Colon: $2,
+			Value: $3,
+		}
+	}
+
+keyvalues_no_comma:
+	keyvalue
+	{
+		$$ = []Expr{$1}
+	}
+|	keyvalues_no_comma ',' keyvalue
+	{
+		$$ = append($1, $3)
+	}
+
+keyvalues:
+	keyvalues_no_comma
+	{
+		$$ = $1
+	}
+|	keyvalues_no_comma ','
+	{
+		$$ = $1
+	}
+
+exprs:
+	expr
+	{
+		$$ = []Expr{$1}
+	}
+|	exprs ',' expr
+	{
+		$$ = append($1, $3)
+	}
+
+exprs_opt:
+	{
+		$$, $<comma>$ = nil, Position{}
+	}
+|	exprs comma_opt
+	{
+		$$, $<comma>$ = $1, $2
+	}
+
+string:
+	_STRING
+	{
+		$$ = &StringExpr{
+			Start: $1,
+			Value: $<str>1,
+			TripleQuote: $<triple>1,
+			End: $1.add($<tok>1),
+			Token: $<tok>1,
+		}
+	}
+
+strings:
+	string
+	{
+		$$ = []*StringExpr{$1}
+	}
+|	strings string
+	{
+		$$ = append($1, $2)
+	}
+
+ident:
+	_IDENT
+	{
+		$$ = &LiteralExpr{Start: $1, Token: $<tok>1}
+	}
+
+idents:
+	ident
+	{
+		$$ = []Expr{$1}
+	}
+|	idents ',' ident
+	{
+		$$ = append($1, $3)
+	}
+
+for_clause:
+	_FOR idents _IN expr
+	{
+		$$ = &ForClause{
+			For: $1,
+			Var: $2,
+			In: $3,
+			Expr: $4,
+		}
+	}
+|	_FOR '(' idents ')' _IN expr
+	{
+		$$ = &ForClause{
+			For: $1,
+			Var: $3,
+			In: $5,
+			Expr: $6,
+		}
+	}
+
+for_clause_with_if_clauses_opt:
+	for_clause if_clauses_opt {
+		$$ = &ForClauseWithIfClausesOpt{
+			For: $1,
+			Ifs: $2,
+		}
+	}
+
+for_clauses_with_if_clauses_opt:
+  for_clause_with_if_clauses_opt
+  {
+    $$ = []*ForClauseWithIfClausesOpt{$1}
+  }
+| for_clauses_with_if_clauses_opt for_clause_with_if_clauses_opt {
+    $$ = append($1, $2)
+  }
+
+if_clauses_opt:
+	{
+		$$ = nil
+	}
+|	if_clauses_opt _IF expr
+	{
+		$$ = append($1, &IfClause{
+			If: $2,
+			Cond: $3,
+		})
+	}
+
+%%
+
+// Go helper code.
+
+// unary returns a unary expression with the given
+// position, operator, and subexpression.
+func unary(pos Position, op string, x Expr) Expr {
+	return &UnaryExpr{
+		OpStart: pos,
+		Op:      op,
+		X:       x,
+	}
+}
+
+// binary returns a binary expression with the given
+// operands, position, and operator.
+func binary(x Expr, pos Position, op string, y Expr) Expr {
+	_, xend := x.Span()
+	ystart, _ := y.Span()
+	return &BinaryExpr{
+		X:       x,
+		OpStart: pos,
+		Op:      op,
+		LineBreak: xend.Line < ystart.Line,
+		Y:       y,
+	}
+}
+
+// forceCompact returns the setting for the ForceCompact field for a call or tuple.
+//
+// NOTE 1: The field is called ForceCompact, not ForceSingleLine,
+// because it only affects the formatting associated with the call or tuple syntax,
+// not the formatting of the arguments. For example:
+//
+//	call([
+//		1,
+//		2,
+//		3,
+//	])
+//
+// is still a compact call even though it runs on multiple lines.
+//
+// In contrast the multiline form puts a linebreak after the (.
+//
+//	call(
+//		[
+//			1,
+//			2,
+//			3,
+//		],
+//	)
+//
+// NOTE 2: Because of NOTE 1, we cannot use start and end on the
+// same line as a signal for compact mode: the formatting of an
+// embedded list might move the end to a different line, which would
+// then look different on rereading and cause buildifier not to be
+// idempotent. Instead, we have to look at properties guaranteed
+// to be preserved by the reformatting, namely that the opening
+// paren and the first expression are on the same line and that
+// each subsequent expression begins on the same line as the last
+// one ended (no line breaks after comma).
+func forceCompact(start Position, list []Expr, end Position) bool {
+	if len(list) <= 1 {
+		// The call or tuple will probably be compact anyway; don't force it.
+		return false
+	}
+
+	// If there are any named arguments or non-string, non-literal
+	// arguments, cannot force compact mode.
+	line := start.Line
+	for _, x := range list {
+		start, end := x.Span()
+		if start.Line != line {
+			return false
+		}
+		line = end.Line
+		switch x.(type) {
+		case *LiteralExpr, *StringExpr, *UnaryExpr:
+			// ok
+		default:
+			return false
+		}
+	}
+	return end.Line == line
+}
+
+// forceMultiLine returns the setting for the ForceMultiLine field.
+func forceMultiLine(start Position, list []Expr, end Position) bool {
+	if len(list) > 1 {
+		// The call will be multiline anyway, because it has multiple elements. Don't force it.
+		return false
+	}
+
+	if len(list) == 0 {
+		// Empty list: use position of brackets.
+		return start.Line != end.Line
+	}
+
+	// Single-element list.
+	// Check whether opening bracket is on different line than beginning of
+	// element, or closing bracket is on different line than end of element.
+	elemStart, elemEnd := list[0].Span()
+	return start.Line != elemStart.Line || end.Line != elemEnd.Line
+}

vendor/github.com/bazelbuild/buildtools/build/print.go

@@ -0,0 +1,614 @@
+/*
+Copyright 2016 Google Inc. All Rights Reserved.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+ WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ See the License for the specific language governing permissions and
+ limitations under the License.
+*/
+// Printing of syntax trees.
+
+package build
+
+import (
+	"bytes"
+	"fmt"
+	"strings"
+)
+
+// Format returns the formatted form of the given BUILD file.
+func Format(f *File) []byte {
+	pr := &printer{}
+	pr.file(f)
+	return pr.Bytes()
+}
+
+// FormatString returns the string form of the given expression.
+func FormatString(x Expr) string {
+	pr := &printer{}
+	switch x := x.(type) {
+	case *File:
+		pr.file(x)
+	default:
+		pr.expr(x, precLow)
+	}
+	return pr.String()
+}
+
+// A printer collects the state during printing of a file or expression.
+type printer struct {
+	bytes.Buffer           // output buffer
+	comment      []Comment // pending end-of-line comments
+	margin       int       // left margin (indent), a number of spaces
+	depth        int       // nesting depth inside ( ) [ ] { }
+}
+
+// printf prints to the buffer.
+func (p *printer) printf(format string, args ...interface{}) {
+	fmt.Fprintf(p, format, args...)
+}
+
+// indent returns the position on the current line, in bytes, 0-indexed.
+func (p *printer) indent() int {
+	b := p.Bytes()
+	n := 0
+	for n < len(b) && b[len(b)-1-n] != '\n' {
+		n++
+	}
+	return n
+}
+
+// newline ends the current line, flushing end-of-line comments.
+// It must only be called when printing a newline is known to be safe:
+// when not inside an expression or when p.depth > 0.
+// To break a line inside an expression that might not be enclosed
+// in brackets of some kind, use breakline instead.
+func (p *printer) newline() {
+	if len(p.comment) > 0 {
+		p.printf("  ")
+		for i, com := range p.comment {
+			if i > 0 {
+				p.trim()
+				p.printf("\n%*s", p.margin, "")
+			}
+			p.printf("%s", strings.TrimSpace(com.Token))
+		}
+		p.comment = p.comment[:0]
+	}
+
+	p.trim()
+	p.printf("\n%*s", p.margin, "")
+}
+
+// breakline breaks the current line, inserting a continuation \ if needed.
+// If no continuation \ is needed, breakline flushes end-of-line comments.
+func (p *printer) breakline() {
+	if p.depth == 0 {
+		// Cannot have both final \ and comments.
+		p.printf(" \\\n%*s", p.margin, "")
+		return
+	}
+
+	// Safe to use newline.
+	p.newline()
+}
+
+// trim removes trailing spaces from the current line.
+func (p *printer) trim() {
+	// Remove trailing space from line we're about to end.
+	b := p.Bytes()
+	n := len(b)
+	for n > 0 && b[n-1] == ' ' {
+		n--
+	}
+	p.Truncate(n)
+}
+
+// file formats the given file into the print buffer.
+func (p *printer) file(f *File) {
+	for _, com := range f.Before {
+		p.printf("%s", strings.TrimSpace(com.Token))
+		p.newline()
+	}
+
+	for i, stmt := range f.Stmt {
+		switch stmt := stmt.(type) {
+		case *CommentBlock:
+			// comments already handled
+
+		case *PythonBlock:
+			for _, com := range stmt.Before {
+				p.printf("%s", strings.TrimSpace(com.Token))
+				p.newline()
+			}
+			p.printf("%s", stmt.Token) // includes trailing newline
+
+		default:
+			p.expr(stmt, precLow)
+			p.newline()
+		}
+
+		for _, com := range stmt.Comment().After {
+			p.printf("%s", strings.TrimSpace(com.Token))
+			p.newline()
+		}
+
+		if i+1 < len(f.Stmt) && !compactStmt(stmt, f.Stmt[i+1]) {
+			p.newline()
+		}
+	}
+
+	for _, com := range f.After {
+		p.printf("%s", strings.TrimSpace(com.Token))
+		p.newline()
+	}
+}
+
+// compactStmt reports whether the pair of statements s1, s2
+// should be printed without an intervening blank line.
+// We omit the blank line when both are subinclude statements
+// and the second one has no leading comments.
+func compactStmt(s1, s2 Expr) bool {
+	if len(s2.Comment().Before) > 0 {
+		return false
+	}
+
+	return (isCall(s1, "subinclude") || isCall(s1, "load")) &&
+		(isCall(s2, "subinclude") || isCall(s2, "load"))
+}
+
+// isCall reports whether x is a call to a function with the given name.
+func isCall(x Expr, name string) bool {
+	c, ok := x.(*CallExpr)
+	if !ok {
+		return false
+	}
+	nam, ok := c.X.(*LiteralExpr)
+	if !ok {
+		return false
+	}
+	return nam.Token == name
+}
+
+// Expression formatting.
+
+// The expression formatter must introduce parentheses to force the
+// meaning described by the parse tree. We preserve parentheses in the
+// input, so extra parentheses are only needed if we have edited the tree.
+//
+// For example consider these expressions:
+//	(1) "x" "y" % foo
+//	(2) "x" + "y" % foo
+//	(3) "x" + ("y" % foo)
+//	(4) ("x" + "y") % foo
+// When we parse (1), we represent the concatenation as an addition.
+// However, if we print the addition back out without additional parens,
+// as in (2), it has the same meaning as (3), which is not the original
+// meaning. To preserve the original meaning we must add parens as in (4).
+//
+// To allow arbitrary rewrites to be formatted properly, we track full
+// operator precedence while printing instead of just handling this one
+// case of string concatenation.
+//
+// The precedences are assigned values low to high. A larger number
+// binds tighter than a smaller number. All binary operators bind
+// left-to-right.
+const (
+	precLow = iota
+	precAssign
+	precComma
+	precColon
+	precIn
+	precOr
+	precAnd
+	precCmp
+	precAdd
+	precMultiply
+	precSuffix
+	precUnary
+	precConcat
+)
+
+// opPrec gives the precedence for operators found in a BinaryExpr.
+var opPrec = map[string]int{
+	"=":   precAssign,
+	"+=":  precAssign,
+	"or":  precOr,
+	"and": precAnd,
+	"<":   precCmp,
+	">":   precCmp,
+	"==":  precCmp,
+	"!=":  precCmp,
+	"<=":  precCmp,
+	">=":  precCmp,
+	"+":   precAdd,
+	"-":   precAdd,
+	"*":   precMultiply,
+	"/":   precMultiply,
+	"%":   precMultiply,
+}
+
+// expr prints the expression v to the print buffer.
+// The value outerPrec gives the precedence of the operator
+// outside expr. If that operator binds tighter than v's operator,
+// expr must introduce parentheses to preserve the meaning
+// of the parse tree (see above).
+func (p *printer) expr(v Expr, outerPrec int) {
+	// Emit line-comments preceding this expression.
+	// If we are in the middle of an expression but not inside ( ) [ ] { }
+	// then we cannot just break the line: we'd have to end it with a \.
+	// However, even then we can't emit line comments since that would
+	// end the expression. This is only a concern if we have rewritten
+	// the parse tree. If comments were okay before this expression in
+	// the original input they're still okay now, in the absense of rewrites.
+	//
+	// TODO(bazel-team): Check whether it is valid to emit comments right now,
+	// and if not, insert them earlier in the output instead, at the most
+	// recent \n not following a \ line.
+	if before := v.Comment().Before; len(before) > 0 {
+		// Want to print a line comment.
+		// Line comments must be at the current margin.
+		p.trim()
+		if p.indent() > 0 {
+			// There's other text on the line. Start a new line.
+			p.printf("\n")
+		}
+		// Re-indent to margin.
+		p.printf("%*s", p.margin, "")
+		for _, com := range before {
+			p.printf("%s", strings.TrimSpace(com.Token))
+			p.newline()
+		}
+	}
+
+	// Do we introduce parentheses?
+	// The result depends on the kind of expression.
+	// Each expression type that might need parentheses
+	// calls addParen with its own precedence.
+	// If parentheses are necessary, addParen prints the
+	// opening parenthesis and sets parenthesized so that
+	// the code after the switch can print the closing one.
+	parenthesized := false
+	addParen := func(prec int) {
+		if prec < outerPrec {
+			p.printf("(")
+			p.depth++
+			parenthesized = true
+		}
+	}
+
+	switch v := v.(type) {
+	default:
+		panic(fmt.Errorf("printer: unexpected type %T", v))
+
+	case *LiteralExpr:
+		p.printf("%s", v.Token)
+
+	case *StringExpr:
+		// If the Token is a correct quoting of Value, use it.
+		// This preserves the specific escaping choices that
+		// BUILD authors have made, and it also works around
+		// b/7272572.
+		if strings.HasPrefix(v.Token, `"`) {
+			s, triple, err := unquote(v.Token)
+			if s == v.Value && triple == v.TripleQuote && err == nil {
+				p.printf("%s", v.Token)
+				break
+			}
+		}
+
+		p.printf("%s", quote(v.Value, v.TripleQuote))
+
+	case *DotExpr:
+		addParen(precSuffix)
+		p.expr(v.X, precSuffix)
+		p.printf(".%s", v.Name)
+
+	case *IndexExpr:
+		addParen(precSuffix)
+		p.expr(v.X, precSuffix)
+		p.printf("[")
+		p.expr(v.Y, precLow)
+		p.printf("]")
+
+	case *KeyValueExpr:
+		p.expr(v.Key, precLow)
+		p.printf(": ")
+		p.expr(v.Value, precLow)
+
+	case *SliceExpr:
+		addParen(precSuffix)
+		p.expr(v.X, precSuffix)
+		p.printf("[")
+		if v.Y != nil {
+			p.expr(v.Y, precLow)
+		}
+		p.printf(":")
+		if v.Z != nil {
+			p.expr(v.Z, precLow)
+		}
+		p.printf("]")
+
+	case *UnaryExpr:
+		addParen(precUnary)
+		if v.Op == "not" {
+			p.printf("not ") // Requires a space after it.
+		} else {
+			p.printf("%s", v.Op)
+		}
+		p.expr(v.X, precUnary)
+
+	case *LambdaExpr:
+		addParen(precColon)
+		p.printf("lambda ")
+		for i, name := range v.Var {
+			if i > 0 {
+				p.printf(", ")
+			}
+			p.expr(name, precLow)
+		}
+		p.printf(": ")
+		p.expr(v.Expr, precColon)
+
+	case *BinaryExpr:
+		// Precedence: use the precedence of the operator.
+		// Since all binary expressions format left-to-right,
+		// it is okay for the left side to reuse the same operator
+		// without parentheses, so we use prec for v.X.
+		// For the same reason, the right side cannot reuse the same
+		// operator, or else a parse tree for a + (b + c), where the ( ) are
+		// not present in the source, will format as a + b + c, which
+		// means (a + b) + c. Treat the right expression as appearing
+		// in a context one precedence level higher: use prec+1 for v.Y.
+		//
+		// Line breaks: if we are to break the line immediately after
+		// the operator, introduce a margin at the current column,
+		// so that the second operand lines up with the first one and
+		// also so that neither operand can use space to the left.
+		// If the operator is an =, indent the right side another 4 spaces.
+		prec := opPrec[v.Op]
+		addParen(prec)
+		m := p.margin
+		if v.LineBreak {
+			p.margin = p.indent()
+			if v.Op == "=" {
+				p.margin += 4
+			}
+		}
+
+		p.expr(v.X, prec)
+		p.printf(" %s", v.Op)
+		if v.LineBreak {
+			p.breakline()
+		} else {
+			p.printf(" ")
+		}
+		p.expr(v.Y, prec+1)
+		p.margin = m
+
+	case *ParenExpr:
+		p.seq("()", []Expr{v.X}, &v.End, modeParen, false, v.ForceMultiLine)
+
+	case *CallExpr:
+		addParen(precSuffix)
+		p.expr(v.X, precSuffix)
+		p.seq("()", v.List, &v.End, modeCall, v.ForceCompact, v.ForceMultiLine)
+
+	case *ListExpr:
+		p.seq("[]", v.List, &v.End, modeList, false, v.ForceMultiLine)
+
+	case *SetExpr:
+		p.seq("{}", v.List, &v.End, modeList, false, v.ForceMultiLine)
+
+	case *TupleExpr:
+		p.seq("()", v.List, &v.End, modeTuple, v.ForceCompact, v.ForceMultiLine)
+
+	case *DictExpr:
+		var list []Expr
+		for _, x := range v.List {
+			list = append(list, x)
+		}
+		p.seq("{}", list, &v.End, modeDict, false, v.ForceMultiLine)
+
+	case *ListForExpr:
+		p.listFor(v)
+
+	case *ConditionalExpr:
+		addParen(precSuffix)
+		p.expr(v.Then, precSuffix)
+		p.printf(" if ")
+		p.expr(v.Test, precSuffix)
+		p.printf(" else ")
+		p.expr(v.Else, precSuffix)
+	}
+
+	// Add closing parenthesis if needed.
+	if parenthesized {
+		p.depth--
+		p.printf(")")
+	}
+
+	// Queue end-of-line comments for printing when we
+	// reach the end of the line.
+	p.comment = append(p.comment, v.Comment().Suffix...)
+}
+
+// A seqMode describes a formatting mode for a sequence of values,
+// like a list or call arguments.
+type seqMode int
+
+const (
+	_ seqMode = iota
+
+	modeCall  // f(x)
+	modeList  // [x]
+	modeTuple // (x,)
+	modeParen // (x)
+	modeDict  // {x:y}
+)
+
+// seq formats a list of values inside a given bracket pair (brack = "()", "[]", "{}").
+// The end node holds any trailing comments to be printed just before the
+// closing bracket.
+// The mode parameter specifies the sequence mode (see above).
+// If multiLine is true, seq avoids the compact form even
+// for 0- and 1-element sequences.
+func (p *printer) seq(brack string, list []Expr, end *End, mode seqMode, forceCompact, forceMultiLine bool) {
+	p.printf("%s", brack[:1])
+	p.depth++
+
+	// If there are line comments, force multiline
+	// so we can print the comments before the closing bracket.
+	for _, x := range list {
+		if len(x.Comment().Before) > 0 {
+			forceMultiLine = true
+		}
+	}
+	if len(end.Before) > 0 {
+		forceMultiLine = true
+	}
+
+	// Resolve possibly ambiguous call arguments explicitly
+	// instead of depending on implicit resolution in logic below.
+	if forceMultiLine {
+		forceCompact = false
+	}
+
+	switch {
+	case len(list) == 0 && !forceMultiLine:
+		// Compact form: print nothing.
+
+	case len(list) == 1 && !forceMultiLine:
+		// Compact form.
+		p.expr(list[0], precLow)
+		// Tuple must end with comma, to mark it as a tuple.
+		if mode == modeTuple {
+			p.printf(",")
+		}
+
+	case forceCompact:
+		// Compact form but multiple elements.
+		for i, x := range list {
+			if i > 0 {
+				p.printf(", ")
+			}
+			p.expr(x, precLow)
+		}
+
+	default:
+		// Multi-line form.
+		p.margin += 4
+		for i, x := range list {
+			// If we are about to break the line before the first
+			// element and there are trailing end-of-line comments
+			// waiting to be printed, delay them and print them as
+			// whole-line comments preceding that element.
+			// Do this by printing a newline ourselves and positioning
+			// so that the end-of-line comment, with the two spaces added,
+			// will line up with the current margin.
+			if i == 0 && len(p.comment) > 0 {
+				p.printf("\n%*s", p.margin-2, "")
+			}
+
+			p.newline()
+			p.expr(x, precLow)
+			if mode != modeParen || i+1 < len(list) {
+				p.printf(",")
+			}
+		}
+		// Final comments.
+		for _, com := range end.Before {
+			p.newline()
+			p.printf("%s", strings.TrimSpace(com.Token))
+		}
+		p.margin -= 4
+		p.newline()
+	}
+	p.depth--
+	p.printf("%s", brack[1:])
+}
+
+// listFor formats a ListForExpr (list comprehension).
+// The single-line form is:
+//	[x for y in z if c]
+//
+// and the multi-line form is:
+//	[
+//	    x
+//	    for y in z
+//	    if c
+//	]
+//
+func (p *printer) listFor(v *ListForExpr) {
+	multiLine := v.ForceMultiLine || len(v.End.Before) > 0
+
+	// space breaks the line in multiline mode
+	// or else prints a space.
+	space := func() {
+		if multiLine {
+			p.breakline()
+		} else {
+			p.printf(" ")
+		}
+	}
+
+	if v.Brack != "" {
+		p.depth++
+		p.printf("%s", v.Brack[:1])
+	}
+
+	if multiLine {
+		if v.Brack != "" {
+			p.margin += 4
+		}
+		p.newline()
+	}
+
+	p.expr(v.X, precLow)
+
+	for _, c := range v.For {
+		space()
+		p.printf("for ")
+		for i, name := range c.For.Var {
+			if i > 0 {
+				p.printf(", ")
+			}
+			p.expr(name, precLow)
+		}
+		p.printf(" in ")
+		p.expr(c.For.Expr, precLow)
+		p.comment = append(p.comment, c.For.Comment().Suffix...)
+
+		for _, i := range c.Ifs {
+			space()
+			p.printf("if ")
+			p.expr(i.Cond, precLow)
+			p.comment = append(p.comment, i.Comment().Suffix...)
+		}
+		p.comment = append(p.comment, c.Comment().Suffix...)
+
+	}
+
+	if multiLine {
+		for _, com := range v.End.Before {
+			p.newline()
+			p.printf("%s", strings.TrimSpace(com.Token))
+		}
+		if v.Brack != "" {
+			p.margin -= 4
+		}
+		p.newline()
+	}
+
+	if v.Brack != "" {
+		p.printf("%s", v.Brack[1:])
+		p.depth--
+	}
+}

vendor/github.com/bazelbuild/buildtools/build/quote.go

@@ -0,0 +1,262 @@
+/*
+Copyright 2016 Google Inc. All Rights Reserved.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+ WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ See the License for the specific language governing permissions and
+ limitations under the License.
+*/
+// Python quoted strings.
+
+package build
+
+import (
+	"bytes"
+	"fmt"
+	"strconv"
+	"strings"
+)
+
+// unesc maps single-letter chars following \ to their actual values.
+var unesc = [256]byte{
+	'a':  '\a',
+	'b':  '\b',
+	'f':  '\f',
+	'n':  '\n',
+	'r':  '\r',
+	't':  '\t',
+	'v':  '\v',
+	'\\': '\\',
+	'\'': '\'',
+	'"':  '"',
+}
+
+// esc maps escape-worthy bytes to the char that should follow \.
+var esc = [256]byte{
+	'\a': 'a',
+	'\b': 'b',
+	'\f': 'f',
+	'\n': 'n',
+	'\r': 'r',
+	'\t': 't',
+	'\v': 'v',
+	'\\': '\\',
+	'\'': '\'',
+	'"':  '"',
+}
+
+// notEsc is a list of characters that can follow a \ in a string value
+// without having to escape the \. That is, since ( is in this list, we
+// quote the Go string "foo\\(bar" as the Python literal "foo\(bar".
+// This really does happen in BUILD files, especially in strings
+// being used as shell arguments containing regular expressions.
+const notEsc = " !#$%&()*+,-./:;<=>?@ABCDEFGHIJKLMNOPQRSTUVWXYZ{|}~"
+
+// unquote unquotes the quoted string, returning the actual
+// string value, whether the original was triple-quoted, and
+// an error describing invalid input.
+func unquote(quoted string) (s string, triple bool, err error) {
+	// Check for raw prefix: means don't interpret the inner \.
+	raw := false
+	if strings.HasPrefix(quoted, "r") {
+		raw = true
+		quoted = quoted[1:]
+	}
+
+	if len(quoted) < 2 {
+		err = fmt.Errorf("string literal too short")
+		return
+	}
+
+	if quoted[0] != '"' && quoted[0] != '\'' || quoted[0] != quoted[len(quoted)-1] {
+		err = fmt.Errorf("string literal has invalid quotes")
+	}
+
+	// Check for triple quoted string.
+	quote := quoted[0]
+	if len(quoted) >= 6 && quoted[1] == quote && quoted[2] == quote && quoted[:3] == quoted[len(quoted)-3:] {
+		triple = true
+		quoted = quoted[3 : len(quoted)-3]
+	} else {
+		quoted = quoted[1 : len(quoted)-1]
+	}
+
+	// Now quoted is the quoted data, but no quotes.
+	// If we're in raw mode or there are no escapes, we're done.
+	if raw || !strings.Contains(quoted, `\`) {
+		s = quoted
+		return
+	}
+
+	// Otherwise process quoted string.
+	// Each iteration processes one escape sequence along with the
+	// plain text leading up to it.
+	var buf bytes.Buffer
+	for {
+		// Remove prefix before escape sequence.
+		i := strings.Index(quoted, `\`)
+		if i < 0 {
+			i = len(quoted)
+		}
+		buf.WriteString(quoted[:i])
+		quoted = quoted[i:]
+
+		if len(quoted) == 0 {
+			break
+		}
+
+		// Process escape sequence.
+		if len(quoted) == 1 {
+			err = fmt.Errorf(`truncated escape sequence \`)
+			return
+		}
+
+		switch quoted[1] {
+		default:
+			// In Python, if \z (for some byte z) is not a known escape sequence
+			// then it appears as literal text in the string.
+			buf.WriteString(quoted[:2])
+			quoted = quoted[2:]
+
+		case '\n':
+			// Ignore the escape and the line break.
+			quoted = quoted[2:]
+
+		case 'a', 'b', 'f', 'n', 'r', 't', 'v', '\\', '\'', '"':
+			// One-char escape
+			buf.WriteByte(unesc[quoted[1]])
+			quoted = quoted[2:]
+
+		case '0', '1', '2', '3', '4', '5', '6', '7':
+			// Octal escape, up to 3 digits.
+			n := int(quoted[1] - '0')
+			quoted = quoted[2:]
+			for i := 1; i < 3; i++ {
+				if len(quoted) == 0 || quoted[0] < '0' || '7' < quoted[0] {
+					break
+				}
+				n = n*8 + int(quoted[0]-'0')
+				quoted = quoted[1:]
+			}
+			if n >= 256 {
+				// NOTE: Python silently discards the high bit,
+				// so that '\541' == '\141' == 'a'.
+				// Let's see if we can avoid doing that in BUILD files.
+				err = fmt.Errorf(`invalid escape sequence \%03o`, n)
+				return
+			}
+			buf.WriteByte(byte(n))
+
+		case 'x':
+			// Hexadecimal escape, exactly 2 digits.
+			if len(quoted) < 4 {
+				err = fmt.Errorf(`truncated escape sequence %s`, quoted)
+				return
+			}
+			n, err1 := strconv.ParseInt(quoted[2:4], 16, 0)
+			if err1 != nil {
+				err = fmt.Errorf(`invalid escape sequence %s`, quoted[:4])
+				return
+			}
+			buf.WriteByte(byte(n))
+			quoted = quoted[4:]
+		}
+	}
+
+	s = buf.String()
+	return
+}
+
+// indexByte returns the index of the first instance of b in s, or else -1.
+func indexByte(s string, b byte) int {
+	for i := 0; i < len(s); i++ {
+		if s[i] == b {
+			return i
+		}
+	}
+	return -1
+}
+
+// hex is a list of the hexadecimal digits, for use in quoting.
+// We always print lower-case hexadecimal.
+const hex = "0123456789abcdef"
+
+// quote returns the quoted form of the string value "x".
+// If triple is true, quote uses the triple-quoted form """x""".
+func quote(unquoted string, triple bool) string {
+	q := `"`
+	if triple {
+		q = `"""`
+	}
+
+	var buf bytes.Buffer
+	buf.WriteString(q)
+
+	for i := 0; i < len(unquoted); i++ {
+		c := unquoted[i]
+		if c == '"' && triple && (i+1 < len(unquoted) && unquoted[i+1] != '"' || i+2 < len(unquoted) && unquoted[i+2] != '"') {
+			// Can pass up to two quotes through, because they are followed by a non-quote byte.
+			buf.WriteByte(c)
+			if i+1 < len(unquoted) && unquoted[i+1] == '"' {
+				buf.WriteByte(c)
+				i++
+			}
+			continue
+		}
+		if triple && c == '\n' {
+			// Can allow newline in triple-quoted string.
+			buf.WriteByte(c)
+			continue
+		}
+		if c == '\'' {
+			// Can allow ' since we always use ".
+			buf.WriteByte(c)
+			continue
+		}
+		if c == '\\' {
+			if i+1 < len(unquoted) && indexByte(notEsc, unquoted[i+1]) >= 0 {
+				// Can pass \ through when followed by a byte that
+				// known not to be a valid escape sequence and also
+				// that does not trigger an escape sequence of its own.
+				// Use this, because various BUILD files do.
+				buf.WriteByte('\\')
+				buf.WriteByte(unquoted[i+1])
+				i++
+				continue
+			}
+		}
+		if esc[c] != 0 {
+			buf.WriteByte('\\')
+			buf.WriteByte(esc[c])
+			continue
+		}
+		if c < 0x20 || c >= 0x80 {
+			// BUILD files are supposed to be Latin-1, so escape all control and high bytes.
+			// I'd prefer to use \x here, but Blaze does not implement
+			// \x in quoted strings (b/7272572).
+			buf.WriteByte('\\')
+			buf.WriteByte(hex[c>>6]) // actually octal but reusing hex digits 0-7.
+			buf.WriteByte(hex[(c>>3)&7])
+			buf.WriteByte(hex[c&7])
+			/*
+				buf.WriteByte('\\')
+				buf.WriteByte('x')
+				buf.WriteByte(hex[c>>4])
+				buf.WriteByte(hex[c&0xF])
+			*/
+			continue
+		}
+		buf.WriteByte(c)
+		continue
+	}
+
+	buf.WriteString(q)
+	return buf.String()
+}

vendor/github.com/bazelbuild/buildtools/build/rewrite.go

@@ -0,0 +1,817 @@
+/*
+Copyright 2016 Google Inc. All Rights Reserved.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+ WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ See the License for the specific language governing permissions and
+ limitations under the License.
+*/
+// Rewriting of high-level (not purely syntactic) BUILD constructs.
+
+package build
+
+import (
+	"path"
+	"regexp"
+	"sort"
+	"strings"
+
+	"github.com/bazelbuild/buildtools/tables"
+)
+
+// For debugging: flag to disable certain rewrites.
+var DisableRewrites []string
+
+// disabled reports whether the named rewrite is disabled.
+func disabled(name string) bool {
+	for _, x := range DisableRewrites {
+		if name == x {
+			return true
+		}
+	}
+	return false
+}
+
+// For debugging: allow sorting of these lists even with sorting otherwise disabled.
+var AllowSort []string
+
+// allowedSort reports whether sorting is allowed in the named context.
+func allowedSort(name string) bool {
+	for _, x := range AllowSort {
+		if name == x {
+			return true
+		}
+	}
+	return false
+}
+
+// Rewrite applies the high-level Buildifier rewrites to f, modifying it in place.
+// If info is non-nil, Rewrite updates it with information about the rewrite.
+func Rewrite(f *File, info *RewriteInfo) {
+	// Allocate an info so that helpers can assume it's there.
+	if info == nil {
+		info = new(RewriteInfo)
+	}
+
+	for _, r := range rewrites {
+		if !disabled(r.name) {
+			r.fn(f, info)
+		}
+	}
+}
+
+// RewriteInfo collects information about what Rewrite did.
+type RewriteInfo struct {
+	EditLabel      int      // number of label strings edited
+	NameCall       int      // number of calls with argument names added
+	SortCall       int      // number of call argument lists sorted
+	SortStringList int      // number of string lists sorted
+	UnsafeSort     int      // number of unsafe string lists sorted
+	Log            []string // log entries - may change
+}
+
+func (info *RewriteInfo) String() string {
+	s := ""
+	if info.EditLabel > 0 {
+		s += " label"
+	}
+	if info.NameCall > 0 {
+		s += " callname"
+	}
+	if info.SortCall > 0 {
+		s += " callsort"
+	}
+	if info.SortStringList > 0 {
+		s += " listsort"
+	}
+	if info.UnsafeSort > 0 {
+		s += " unsafesort"
+	}
+	if s != "" {
+		s = s[1:]
+	}
+	return s
+}
+
+// rewrites is the list of all Buildifier rewrites, in the order in which they are applied.
+// The order here matters: for example, label canonicalization must happen
+// before sorting lists of strings.
+var rewrites = []struct {
+	name string
+	fn   func(*File, *RewriteInfo)
+}{
+	{"callsort", sortCallArgs},
+	{"label", fixLabels},
+	{"listsort", sortStringLists},
+	{"multiplus", fixMultilinePlus},
+}
+
+// leaveAlone reports whether any of the nodes on the stack are marked
+// with a comment containing "buildifier: leave-alone".
+func leaveAlone(stk []Expr, final Expr) bool {
+	for _, x := range stk {
+		if leaveAlone1(x) {
+			return true
+		}
+	}
+	if final != nil && leaveAlone1(final) {
+		return true
+	}
+	return false
+}
+
+// hasComment reports whether x is marked with a comment that
+// after being converted to lower case, contains the specified text.
+func hasComment(x Expr, text string) bool {
+	for _, com := range x.Comment().Before {
+		if strings.Contains(strings.ToLower(com.Token), text) {
+			return true
+		}
+	}
+	return false
+}
+
+// leaveAlone1 reports whether x is marked with a comment containing
+// "buildifier: leave-alone", case-insensitive.
+func leaveAlone1(x Expr) bool {
+	return hasComment(x, "buildifier: leave-alone")
+}
+
+// doNotSort reports whether x is marked with a comment containing
+// "do not sort", case-insensitive.
+func doNotSort(x Expr) bool {
+	return hasComment(x, "do not sort")
+}
+
+// keepSorted reports whether x is marked with a comment containing
+// "keep sorted", case-insensitive.
+func keepSorted(x Expr) bool {
+	return hasComment(x, "keep sorted")
+}
+
+// fixLabels rewrites labels into a canonical form.
+//
+// First, it joins labels written as string addition, turning
+// "//x" + ":y" (usually split across multiple lines) into "//x:y".
+//
+// Second, it removes redundant target qualifiers, turning labels like
+// "//third_party/m4:m4" into "//third_party/m4" as well as ones like
+// "@foo//:foo" into "@foo".
+//
+func fixLabels(f *File, info *RewriteInfo) {
+	joinLabel := func(p *Expr) {
+		add, ok := (*p).(*BinaryExpr)
+		if !ok || add.Op != "+" {
+			return
+		}
+		str1, ok := add.X.(*StringExpr)
+		if !ok || !strings.HasPrefix(str1.Value, "//") || strings.Contains(str1.Value, " ") {
+			return
+		}
+		str2, ok := add.Y.(*StringExpr)
+		if !ok || strings.Contains(str2.Value, " ") {
+			return
+		}
+		info.EditLabel++
+		str1.Value += str2.Value
+
+		// Deleting nodes add and str2.
+		// Merge comments from add, str1, and str2 and save in str1.
+		com1 := add.Comment()
+		com2 := str1.Comment()
+		com3 := str2.Comment()
+		com1.Before = append(com1.Before, com2.Before...)
+		com1.Before = append(com1.Before, com3.Before...)
+		com1.Suffix = append(com1.Suffix, com2.Suffix...)
+		com1.Suffix = append(com1.Suffix, com3.Suffix...)
+		*str1.Comment() = *com1
+
+		*p = str1
+	}
+
+	labelPrefix := "//"
+	if tables.StripLabelLeadingSlashes {
+		labelPrefix = ""
+	}
+	// labelRE matches label strings, e.g. @r//x/y/z:abc
+	// where $1 is @r//x/y/z, $2 is @r//, $3 is r, $4 is z, $5 is abc.
+	labelRE := regexp.MustCompile(`^(((?:@(\w+))?//|` + labelPrefix + `)(?:.+/)?([^:]*))(?::([^:]+))?$`)
+
+	shortenLabel := func(v Expr) {
+		str, ok := v.(*StringExpr)
+		if !ok {
+			return
+		}
+		editPerformed := false
+
+		if tables.StripLabelLeadingSlashes && strings.HasPrefix(str.Value, "//") {
+			if path.Dir(f.Path) == "." || !strings.HasPrefix(str.Value, "//:") {
+				editPerformed = true
+				str.Value = str.Value[2:]
+			}
+		}
+
+		if tables.ShortenAbsoluteLabelsToRelative {
+			thisPackage := labelPrefix + path.Dir(f.Path)
+			if str.Value == thisPackage {
+				editPerformed = true
+				str.Value = ":" + path.Base(str.Value)
+			} else if strings.HasPrefix(str.Value, thisPackage+":") {
+				editPerformed = true
+				str.Value = str.Value[len(thisPackage):]
+			}
+		}
+
+		m := labelRE.FindStringSubmatch(str.Value)
+		if m == nil {
+			return
+		}
+		if m[4] != "" && m[4] == m[5] { // e.g. //foo:foo
+			editPerformed = true
+			str.Value = m[1]
+		} else if m[3] != "" && m[4] == "" && m[3] == m[5] { // e.g. @foo//:foo
+			editPerformed = true
+			str.Value = "@" + m[3]
+		}
+		if editPerformed {
+			info.EditLabel++
+		}
+	}
+
+	Walk(f, func(v Expr, stk []Expr) {
+		switch v := v.(type) {
+		case *CallExpr:
+			if leaveAlone(stk, v) {
+				return
+			}
+			for i := range v.List {
+				if leaveAlone1(v.List[i]) {
+					continue
+				}
+				as, ok := v.List[i].(*BinaryExpr)
+				if !ok || as.Op != "=" {
+					continue
+				}
+				key, ok := as.X.(*LiteralExpr)
+				if !ok || !tables.IsLabelArg[key.Token] || tables.LabelBlacklist[callName(v)+"."+key.Token] {
+					continue
+				}
+				if leaveAlone1(as.Y) {
+					continue
+				}
+				if list, ok := as.Y.(*ListExpr); ok {
+					for i := range list.List {
+						if leaveAlone1(list.List[i]) {
+							continue
+						}
+						joinLabel(&list.List[i])
+						shortenLabel(list.List[i])
+					}
+				}
+				if set, ok := as.Y.(*SetExpr); ok {
+					for i := range set.List {
+						if leaveAlone1(set.List[i]) {
+							continue
+						}
+						joinLabel(&set.List[i])
+						shortenLabel(set.List[i])
+					}
+				} else {
+					joinLabel(&as.Y)
+					shortenLabel(as.Y)
+				}
+			}
+		}
+	})
+}
+
+// callName returns the name of the rule being called by call.
+// If the call is not to a literal rule name, callName returns "".
+func callName(call *CallExpr) string {
+	rule, ok := call.X.(*LiteralExpr)
+	if !ok {
+		return ""
+	}
+	return rule.Token
+}
+
+// sortCallArgs sorts lists of named arguments to a call.
+func sortCallArgs(f *File, info *RewriteInfo) {
+	Walk(f, func(v Expr, stk []Expr) {
+		call, ok := v.(*CallExpr)
+		if !ok {
+			return
+		}
+		if leaveAlone(stk, call) {
+			return
+		}
+		rule := callName(call)
+		if rule == "" {
+			return
+		}
+
+		// Find the tail of the argument list with named arguments.
+		start := len(call.List)
+		for start > 0 && argName(call.List[start-1]) != "" {
+			start--
+		}
+
+		// Record information about each arg into a sortable list.
+		var args namedArgs
+		for i, x := range call.List[start:] {
+			name := argName(x)
+			args = append(args, namedArg{ruleNamePriority(rule, name), name, i, x})
+		}
+
+		// Sort the list and put the args back in the new order.
+		if sort.IsSorted(args) {
+			return
+		}
+		info.SortCall++
+		sort.Sort(args)
+		for i, x := range args {
+			call.List[start+i] = x.expr
+		}
+	})
+}
+
+// ruleNamePriority maps a rule argument name to its sorting priority.
+// It could use the auto-generated per-rule tables but for now it just
+// falls back to the original list.
+func ruleNamePriority(rule, arg string) int {
+	ruleArg := rule + "." + arg
+	if val, ok := tables.NamePriority[ruleArg]; ok {
+		return val
+	}
+	return tables.NamePriority[arg]
+	/*
+		list := ruleArgOrder[rule]
+		if len(list) == 0 {
+			return tables.NamePriority[arg]
+		}
+		for i, x := range list {
+			if x == arg {
+				return i
+			}
+		}
+		return len(list)
+	*/
+}
+
+// If x is of the form key=value, argName returns the string key.
+// Otherwise argName returns "".
+func argName(x Expr) string {
+	if as, ok := x.(*BinaryExpr); ok && as.Op == "=" {
+		if id, ok := as.X.(*LiteralExpr); ok {
+			return id.Token
+		}
+	}
+	return ""
+}
+
+// A namedArg records information needed for sorting
+// a named call argument into its proper position.
+type namedArg struct {
+	priority int    // kind of name; first sort key
+	name     string // name; second sort key
+	index    int    // original index; final sort key
+	expr     Expr   // name=value argument
+}
+
+// namedArgs is a slice of namedArg that implements sort.Interface
+type namedArgs []namedArg
+
+func (x namedArgs) Len() int      { return len(x) }
+func (x namedArgs) Swap(i, j int) { x[i], x[j] = x[j], x[i] }
+
+func (x namedArgs) Less(i, j int) bool {
+	p := x[i]
+	q := x[j]
+	if p.priority != q.priority {
+		return p.priority < q.priority
+	}
+	if p.name != q.name {
+		return p.name < q.name
+	}
+	return p.index < q.index
+}
+
+// sortStringLists sorts lists of string literals used as specific rule arguments.
+func sortStringLists(f *File, info *RewriteInfo) {
+	Walk(f, func(v Expr, stk []Expr) {
+		switch v := v.(type) {
+		case *CallExpr:
+			if leaveAlone(stk, v) {
+				return
+			}
+			rule := callName(v)
+			for _, arg := range v.List {
+				if leaveAlone1(arg) {
+					continue
+				}
+				as, ok := arg.(*BinaryExpr)
+				if !ok || as.Op != "=" || leaveAlone1(as) || doNotSort(as) {
+					continue
+				}
+				key, ok := as.X.(*LiteralExpr)
+				if !ok {
+					continue
+				}
+				context := rule + "." + key.Token
+				if !tables.IsSortableListArg[key.Token] || tables.SortableBlacklist[context] {
+					continue
+				}
+				if disabled("unsafesort") && !tables.SortableWhitelist[context] && !allowedSort(context) {
+					continue
+				}
+				sortStringList(as.Y, info, context)
+			}
+		case *BinaryExpr:
+			if disabled("unsafesort") {
+				return
+			}
+			// "keep sorted" comment on x = list forces sorting of list.
+			as := v
+			if as.Op == "=" && keepSorted(as) {
+				sortStringList(as.Y, info, "?")
+			}
+		case *KeyValueExpr:
+			if disabled("unsafesort") {
+				return
+			}
+			// "keep sorted" before key: list also forces sorting of list.
+			if keepSorted(v) {
+				sortStringList(v.Value, info, "?")
+			}
+		case *ListExpr:
+			if disabled("unsafesort") {
+				return
+			}
+			// "keep sorted" comment above first list element also forces sorting of list.
+			if len(v.List) > 0 && keepSorted(v.List[0]) {
+				sortStringList(v, info, "?")
+			}
+		}
+	})
+}
+
+// SortStringList sorts x, a list of strings.
+func SortStringList(x Expr) {
+	sortStringList(x, nil, "")
+}
+
+// sortStringList sorts x, a list of strings.
+// The list is broken by non-strings and by blank lines and comments into chunks.
+// Each chunk is sorted in place.
+func sortStringList(x Expr, info *RewriteInfo, context string) {
+	list, ok := x.(*ListExpr)
+	if !ok || len(list.List) < 2 || doNotSort(list.List[0]) {
+		return
+	}
+
+	forceSort := keepSorted(list.List[0])
+
+	// TODO(bazel-team): Decide how to recognize lists that cannot
+	// be sorted. Avoiding all lists with comments avoids sorting
+	// lists that say explicitly, in some form or another, why they
+	// cannot be sorted. For example, many cc_test rules require
+	// certain order in their deps attributes.
+	if !forceSort {
+		if line, _ := hasComments(list); line {
+			return
+		}
+	}
+
+	// Sort chunks of the list with no intervening blank lines or comments.
+	for i := 0; i < len(list.List); {
+		if _, ok := list.List[i].(*StringExpr); !ok {
+			i++
+			continue
+		}
+
+		j := i + 1
+		for ; j < len(list.List); j++ {
+			if str, ok := list.List[j].(*StringExpr); !ok || len(str.Before) > 0 {
+				break
+			}
+		}
+
+		var chunk []stringSortKey
+		for index, x := range list.List[i:j] {
+			chunk = append(chunk, makeSortKey(index, x.(*StringExpr)))
+		}
+		if !sort.IsSorted(byStringExpr(chunk)) || !isUniq(chunk) {
+			if info != nil {
+				info.SortStringList++
+				if !tables.SortableWhitelist[context] {
+					info.UnsafeSort++
+					info.Log = append(info.Log, "sort:"+context)
+				}
+			}
+			before := chunk[0].x.Comment().Before
+			chunk[0].x.Comment().Before = nil
+
+			sort.Sort(byStringExpr(chunk))
+			chunk = uniq(chunk)
+
+			chunk[0].x.Comment().Before = before
+			for offset, key := range chunk {
+				list.List[i+offset] = key.x
+			}
+			list.List = append(list.List[:(i+len(chunk))], list.List[j:]...)
+		}
+
+		i = j
+	}
+}
+
+// uniq removes duplicates from a list, which must already be sorted.
+// It edits the list in place.
+func uniq(sortedList []stringSortKey) []stringSortKey {
+	out := sortedList[:0]
+	for _, sk := range sortedList {
+		if len(out) == 0 || sk.value != out[len(out)-1].value {
+			out = append(out, sk)
+		}
+	}
+	return out
+}
+
+// isUniq reports whether the sorted list only contains unique elements.
+func isUniq(list []stringSortKey) bool {
+	for i := range list {
+		if i+1 < len(list) && list[i].value == list[i+1].value {
+			return false
+		}
+	}
+	return true
+}
+
+// If stk describes a call argument like rule(arg=...), callArgName
+// returns the name of that argument, formatted as "rule.arg".
+func callArgName(stk []Expr) string {
+	n := len(stk)
+	if n < 2 {
+		return ""
+	}
+	arg := argName(stk[n-1])
+	if arg == "" {
+		return ""
+	}
+	call, ok := stk[n-2].(*CallExpr)
+	if !ok {
+		return ""
+	}
+	rule, ok := call.X.(*LiteralExpr)
+	if !ok {
+		return ""
+	}
+	return rule.Token + "." + arg
+}
+
+// A stringSortKey records information about a single string literal to be
+// sorted. The strings are first grouped into four phases: most strings,
+// strings beginning with ":", strings beginning with "//", and strings
+// beginning with "@". The next significant part of the comparison is the list
+// of elements in the value, where elements are split at `.' and `:'. Finally
+// we compare by value and break ties by original index.
+type stringSortKey struct {
+	phase    int
+	split    []string
+	value    string
+	original int
+	x        Expr
+}
+
+func makeSortKey(index int, x *StringExpr) stringSortKey {
+	key := stringSortKey{
+		value:    x.Value,
+		original: index,
+		x:        x,
+	}
+
+	switch {
+	case strings.HasPrefix(x.Value, ":"):
+		key.phase = 1
+	case strings.HasPrefix(x.Value, "//") || (tables.StripLabelLeadingSlashes && !strings.HasPrefix(x.Value, "@")):
+		key.phase = 2
+	case strings.HasPrefix(x.Value, "@"):
+		key.phase = 3
+	}
+
+	key.split = strings.Split(strings.Replace(x.Value, ":", ".", -1), ".")
+	return key
+}
+
+// byStringExpr implements sort.Interface for a list of stringSortKey.
+type byStringExpr []stringSortKey
+
+func (x byStringExpr) Len() int      { return len(x) }
+func (x byStringExpr) Swap(i, j int) { x[i], x[j] = x[j], x[i] }
+
+func (x byStringExpr) Less(i, j int) bool {
+	xi := x[i]
+	xj := x[j]
+
+	if xi.phase != xj.phase {
+		return xi.phase < xj.phase
+	}
+	for k := 0; k < len(xi.split) && k < len(xj.split); k++ {
+		if xi.split[k] != xj.split[k] {
+			return xi.split[k] < xj.split[k]
+		}
+	}
+	if len(xi.split) != len(xj.split) {
+		return len(xi.split) < len(xj.split)
+	}
+	if xi.value != xj.value {
+		return xi.value < xj.value
+	}
+	return xi.original < xj.original
+}
+
+// fixMultilinePlus turns
+//
+//	... +
+//	[ ... ]
+//
+//	... +
+//	call(...)
+//
+// into
+//	... + [
+//		...
+//	]
+//
+//	... + call(
+//		...
+//	)
+//
+// which typically works better with our aggressively compact formatting.
+func fixMultilinePlus(f *File, info *RewriteInfo) {
+
+	// List manipulation helpers.
+	// As a special case, we treat f([...]) as a list, mainly
+	// for glob.
+
+	// isList reports whether x is a list.
+	var isList func(x Expr) bool
+	isList = func(x Expr) bool {
+		switch x := x.(type) {
+		case *ListExpr:
+			return true
+		case *CallExpr:
+			if len(x.List) == 1 {
+				return isList(x.List[0])
+			}
+		}
+		return false
+	}
+
+	// isMultiLine reports whether x is a multiline list.
+	var isMultiLine func(Expr) bool
+	isMultiLine = func(x Expr) bool {
+		switch x := x.(type) {
+		case *ListExpr:
+			return x.ForceMultiLine || len(x.List) > 1
+		case *CallExpr:
+			if x.ForceMultiLine || len(x.List) > 1 && !x.ForceCompact {
+				return true
+			}
+			if len(x.List) == 1 {
+				return isMultiLine(x.List[0])
+			}
+		}
+		return false
+	}
+
+	// forceMultiLine tries to force the list x to use a multiline form.
+	// It reports whether it was successful.
+	var forceMultiLine func(Expr) bool
+	forceMultiLine = func(x Expr) bool {
+		switch x := x.(type) {
+		case *ListExpr:
+			// Already multi line?
+			if x.ForceMultiLine {
+				return true
+			}
+			// If this is a list containing a list, force the
+			// inner list to be multiline instead.
+			if len(x.List) == 1 && forceMultiLine(x.List[0]) {
+				return true
+			}
+			x.ForceMultiLine = true
+			return true
+
+		case *CallExpr:
+			if len(x.List) == 1 {
+				return forceMultiLine(x.List[0])
+			}
+		}
+		return false
+	}
+
+	skip := map[Expr]bool{}
+	Walk(f, func(v Expr, stk []Expr) {
+		if skip[v] {
+			return
+		}
+		bin, ok := v.(*BinaryExpr)
+		if !ok || bin.Op != "+" {
+			return
+		}
+
+		// Found a +.
+		// w + x + y + z parses as ((w + x) + y) + z,
+		// so chase down the left side to make a list of
+		// all the things being added together, separated
+		// by the BinaryExprs that join them.
+		// Mark them as "skip" so that when Walk recurses
+		// into the subexpressions, we won't reprocess them.
+		var all []Expr
+		for {
+			all = append(all, bin.Y, bin)
+			bin1, ok := bin.X.(*BinaryExpr)
+			if !ok || bin1.Op != "+" {
+				break
+			}
+			bin = bin1
+			skip[bin] = true
+		}
+		all = append(all, bin.X)
+
+		// Because the outermost expression was the
+		// rightmost one, the list is backward. Reverse it.
+		for i, j := 0, len(all)-1; i < j; i, j = i+1, j-1 {
+			all[i], all[j] = all[j], all[i]
+		}
+
+		// The 'all' slice is alternating addends and BinaryExpr +'s:
+		//	w, +, x, +, y, +, z
+		// If there are no lists involved, don't rewrite anything.
+		haveList := false
+		for i := 0; i < len(all); i += 2 {
+			if isList(all[i]) {
+				haveList = true
+				break
+			}
+		}
+		if !haveList {
+			return
+		}
+
+		// Okay, there are lists.
+		// Consider each + next to a line break.
+		for i := 1; i < len(all); i += 2 {
+			bin := all[i].(*BinaryExpr)
+			if !bin.LineBreak {
+				continue
+			}
+
+			// We're going to break the line after the +.
+			// If it is followed by a list, force that to be
+			// multiline instead.
+			if forceMultiLine(all[i+1]) {
+				bin.LineBreak = false
+				continue
+			}
+
+			// If the previous list was multiline already,
+			// don't bother with the line break after
+			// the +.
+			if isMultiLine(all[i-1]) {
+				bin.LineBreak = false
+				continue
+			}
+		}
+	})
+}
+
+// hasComments reports whether any comments are associated with
+// the list or its elements.
+func hasComments(list *ListExpr) (line, suffix bool) {
+	com := list.Comment()
+	if len(com.Before) > 0 || len(com.After) > 0 || len(list.End.Before) > 0 {
+		line = true
+	}
+	if len(com.Suffix) > 0 {
+		suffix = true
+	}
+	for _, elem := range list.List {
+		com := elem.Comment()
+		if len(com.Before) > 0 {
+			line = true
+		}
+		if len(com.Suffix) > 0 {
+			suffix = true
+		}
+	}
+	return
+}

vendor/github.com/bazelbuild/buildtools/build/rule.go

@@ -0,0 +1,260 @@
+/*
+Copyright 2016 Google Inc. All Rights Reserved.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+ WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ See the License for the specific language governing permissions and
+ limitations under the License.
+*/
+
+// Rule-level API for inspecting and modifying a build.File syntax tree.
+
+package build
+
+import "strings"
+
+// A Rule represents a single BUILD rule.
+type Rule struct {
+	Call *CallExpr
+}
+
+// Rules returns the rules in the file of the given kind (such as "go_library").
+// If kind == "", Rules returns all rules in the file.
+func (f *File) Rules(kind string) []*Rule {
+	var all []*Rule
+	for _, stmt := range f.Stmt {
+		call, ok := stmt.(*CallExpr)
+		if !ok {
+			continue
+		}
+		rule := &Rule{call}
+		if kind != "" && rule.Kind() != kind {
+			continue
+		}
+		all = append(all, rule)
+	}
+	return all
+}
+
+// RuleAt returns the rule in the file that starts at the specified line, or null if no such rule.
+func (f *File) RuleAt(linenum int) *Rule {
+	for _, stmt := range f.Stmt {
+		call, ok := stmt.(*CallExpr)
+		if !ok {
+			continue
+		}
+		start, end := call.X.Span()
+		if start.Line <= linenum && linenum <= end.Line {
+			return &Rule{call}
+		}
+	}
+	return nil
+}
+
+// DelRules removes rules with the given kind and name from the file.
+// An empty kind matches all kinds; an empty name matches all names.
+// It returns the number of rules that were deleted.
+func (f *File) DelRules(kind, name string) int {
+	var i int
+	for _, stmt := range f.Stmt {
+		if call, ok := stmt.(*CallExpr); ok {
+			r := &Rule{call}
+			if (kind == "" || r.Kind() == kind) &&
+				(name == "" || r.AttrString("name") == name) {
+				continue
+			}
+		}
+		f.Stmt[i] = stmt
+		i++
+	}
+	n := len(f.Stmt) - i
+	f.Stmt = f.Stmt[:i]
+	return n
+}
+
+// Kind returns the rule's kind (such as "go_library").
+// The kind of the rule may be given by a literal or it may be a sequence of dot expressions that
+// begins with a literal, if the call expression does not conform to either of these forms, an
+// empty string will be returned
+func (r *Rule) Kind() string {
+	var names []string
+	expr := r.Call.X
+	for {
+		x, ok := expr.(*DotExpr)
+		if !ok {
+			break
+		}
+		names = append(names, x.Name)
+		expr = x.X
+	}
+	x, ok := expr.(*LiteralExpr)
+	if !ok {
+		return ""
+	}
+	names = append(names, x.Token)
+	// Reverse the elements since the deepest expression contains the leading literal
+	for l, r := 0, len(names)-1; l < r; l, r = l+1, r-1 {
+		names[l], names[r] = names[r], names[l]
+	}
+	return strings.Join(names, ".")
+}
+
+// SetKind changes rule's kind (such as "go_library").
+func (r *Rule) SetKind(kind string) {
+	names := strings.Split(kind, ".")
+	var expr Expr
+	expr = &LiteralExpr{Token: names[0]}
+	for _, name := range names[1:] {
+		expr = &DotExpr{X: expr, Name: name}
+	}
+	r.Call.X = expr
+}
+
+// Name returns the rule's target name.
+// If the rule has no target name, Name returns the empty string.
+func (r *Rule) Name() string {
+	return r.AttrString("name")
+}
+
+// AttrKeys returns the keys of all the rule's attributes.
+func (r *Rule) AttrKeys() []string {
+	var keys []string
+	for _, expr := range r.Call.List {
+		if binExpr, ok := expr.(*BinaryExpr); ok && binExpr.Op == "=" {
+			if keyExpr, ok := binExpr.X.(*LiteralExpr); ok {
+				keys = append(keys, keyExpr.Token)
+			}
+		}
+	}
+	return keys
+}
+
+// AttrDefn returns the BinaryExpr defining the rule's attribute with the given key.
+// That is, the result is a *BinaryExpr with Op == "=".
+// If the rule has no such attribute, AttrDefn returns nil.
+func (r *Rule) AttrDefn(key string) *BinaryExpr {
+	for _, kv := range r.Call.List {
+		as, ok := kv.(*BinaryExpr)
+		if !ok || as.Op != "=" {
+			continue
+		}
+		k, ok := as.X.(*LiteralExpr)
+		if !ok || k.Token != key {
+			continue
+		}
+		return as
+	}
+	return nil
+}
+
+// Attr returns the value of the rule's attribute with the given key
+// (such as "name" or "deps").
+// If the rule has no such attribute, Attr returns nil.
+func (r *Rule) Attr(key string) Expr {
+	as := r.AttrDefn(key)
+	if as == nil {
+		return nil
+	}
+	return as.Y
+}
+
+// DelAttr deletes the rule's attribute with the named key.
+// It returns the old value of the attribute, or nil if the attribute was not found.
+func (r *Rule) DelAttr(key string) Expr {
+	list := r.Call.List
+	for i, kv := range list {
+		as, ok := kv.(*BinaryExpr)
+		if !ok || as.Op != "=" {
+			continue
+		}
+		k, ok := as.X.(*LiteralExpr)
+		if !ok || k.Token != key {
+			continue
+		}
+		copy(list[i:], list[i+1:])
+		r.Call.List = list[:len(list)-1]
+		return as.Y
+	}
+	return nil
+}
+
+// SetAttr sets the rule's attribute with the given key to value.
+// If the rule has no attribute with the key, SetAttr appends
+// one to the end of the rule's attribute list.
+func (r *Rule) SetAttr(key string, val Expr) {
+	as := r.AttrDefn(key)
+	if as != nil {
+		as.Y = val
+		return
+	}
+
+	r.Call.List = append(r.Call.List,
+		&BinaryExpr{
+			X:  &LiteralExpr{Token: key},
+			Op: "=",
+			Y:  val,
+		},
+	)
+}
+
+// AttrLiteral returns the literal form of the rule's attribute
+// with the given key (such as "cc_api_version"), only when
+// that value is an identifier or number.
+// If the rule has no such attribute or the attribute is not an identifier or number,
+// AttrLiteral returns "".
+func (r *Rule) AttrLiteral(key string) string {
+	lit, ok := r.Attr(key).(*LiteralExpr)
+	if !ok {
+		return ""
+	}
+	return lit.Token
+}
+
+// AttrString returns the value of the rule's attribute
+// with the given key (such as "name"), as a string.
+// If the rule has no such attribute or the attribute has a non-string value,
+// Attr returns the empty string.
+func (r *Rule) AttrString(key string) string {
+	str, ok := r.Attr(key).(*StringExpr)
+	if !ok {
+		return ""
+	}
+	return str.Value
+}
+
+// AttrStrings returns the value of the rule's attribute
+// with the given key (such as "srcs"), as a []string.
+// If the rule has no such attribute or the attribute is not
+// a list of strings, AttrStrings returns a nil slice.
+func (r *Rule) AttrStrings(key string) []string {
+	return Strings(r.Attr(key))
+}
+
+// Strings returns expr as a []string.
+// If expr is not a list of string literals,
+// Strings returns a nil slice instead.
+// If expr is an empty list of string literals,
+// returns a non-nil empty slice.
+// (this allows differentiating between these two cases)
+func Strings(expr Expr) []string {
+	list, ok := expr.(*ListExpr)
+	if !ok {
+		return nil
+	}
+	all := []string{} // not nil
+	for _, l := range list.List {
+		str, ok := l.(*StringExpr)
+		if !ok {
+			return nil
+		}
+		all = append(all, str.Value)
+	}
+	return all
+}

vendor/github.com/bazelbuild/buildtools/build/syntax.go

@@ -0,0 +1,423 @@
+/*
+Copyright 2016 Google Inc. All Rights Reserved.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+ WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ See the License for the specific language governing permissions and
+ limitations under the License.
+*/
+
+// Package build implements parsing and printing of BUILD files.
+package build
+
+// Syntax data structure definitions.
+
+import (
+	"strings"
+	"unicode/utf8"
+)
+
+// A Position describes the position between two bytes of input.
+type Position struct {
+	Line     int // line in input (starting at 1)
+	LineRune int // rune in line (starting at 1)
+	Byte     int // byte in input (starting at 0)
+}
+
+// add returns the position at the end of s, assuming it starts at p.
+func (p Position) add(s string) Position {
+	p.Byte += len(s)
+	if n := strings.Count(s, "\n"); n > 0 {
+		p.Line += n
+		s = s[strings.LastIndex(s, "\n")+1:]
+		p.LineRune = 1
+	}
+	p.LineRune += utf8.RuneCountInString(s)
+	return p
+}
+
+// An Expr represents an input element.
+type Expr interface {
+	// Span returns the start and end position of the expression,
+	// excluding leading or trailing comments.
+	Span() (start, end Position)
+
+	// Comment returns the comments attached to the expression.
+	// This method would normally be named 'Comments' but that
+	// would interfere with embedding a type of the same name.
+	Comment() *Comments
+}
+
+// A Comment represents a single # comment.
+type Comment struct {
+	Start  Position
+	Token  string // without trailing newline
+	Suffix bool   // an end of line (not whole line) comment
+}
+
+// Comments collects the comments associated with an expression.
+type Comments struct {
+	Before []Comment // whole-line comments before this expression
+	Suffix []Comment // end-of-line comments after this expression
+
+	// For top-level expressions only, After lists whole-line
+	// comments following the expression.
+	After []Comment
+}
+
+// Comment returns the receiver. This isn't useful by itself, but
+// a Comments struct is embedded into all the expression
+// implementation types, and this gives each of those a Comment
+// method to satisfy the Expr interface.
+func (c *Comments) Comment() *Comments {
+	return c
+}
+
+// A File represents an entire BUILD file.
+type File struct {
+	Path string // file path, relative to workspace directory
+	Comments
+	Stmt []Expr
+}
+
+func (x *File) Span() (start, end Position) {
+	if len(x.Stmt) == 0 {
+		return
+	}
+	start, _ = x.Stmt[0].Span()
+	_, end = x.Stmt[len(x.Stmt)-1].Span()
+	return start, end
+}
+
+// A CommentBlock represents a top-level block of comments separate
+// from any rule.
+type CommentBlock struct {
+	Comments
+	Start Position
+}
+
+func (x *CommentBlock) Span() (start, end Position) {
+	return x.Start, x.Start
+}
+
+// A PythonBlock represents a blob of Python code, typically a def or for loop.
+type PythonBlock struct {
+	Comments
+	Start Position
+	Token string // raw Python code, including final newline
+}
+
+func (x *PythonBlock) Span() (start, end Position) {
+	return x.Start, x.Start.add(x.Token)
+}
+
+// A LiteralExpr represents a literal identifier or number.
+type LiteralExpr struct {
+	Comments
+	Start Position
+	Token string // identifier token
+}
+
+func (x *LiteralExpr) Span() (start, end Position) {
+	return x.Start, x.Start.add(x.Token)
+}
+
+// A StringExpr represents a single literal string.
+type StringExpr struct {
+	Comments
+	Start       Position
+	Value       string // string value (decoded)
+	TripleQuote bool   // triple quote output
+	End         Position
+
+	// To allow specific formatting of string literals,
+	// at least within our requirements, record the
+	// preferred form of Value. This field is a hint:
+	// it is only used if it is a valid quoted form for Value.
+	Token string
+}
+
+func (x *StringExpr) Span() (start, end Position) {
+	return x.Start, x.End
+}
+
+// An End represents the end of a parenthesized or bracketed expression.
+// It is a place to hang comments.
+type End struct {
+	Comments
+	Pos Position
+}
+
+func (x *End) Span() (start, end Position) {
+	return x.Pos, x.Pos.add(")")
+}
+
+// A CallExpr represents a function call expression: X(List).
+type CallExpr struct {
+	Comments
+	X              Expr
+	ListStart      Position // position of (
+	List           []Expr
+	End                 // position of )
+	ForceCompact   bool // force compact (non-multiline) form when printing
+	ForceMultiLine bool // force multiline form when printing
+}
+
+func (x *CallExpr) Span() (start, end Position) {
+	start, _ = x.X.Span()
+	return start, x.End.Pos.add(")")
+}
+
+// A DotExpr represents a field selector: X.Name.
+type DotExpr struct {
+	Comments
+	X       Expr
+	Dot     Position
+	NamePos Position
+	Name    string
+}
+
+func (x *DotExpr) Span() (start, end Position) {
+	start, _ = x.X.Span()
+	return start, x.NamePos.add(x.Name)
+}
+
+// A ListForExpr represents a list comprehension expression: [X for ... if ...].
+type ListForExpr struct {
+	Comments
+	ForceMultiLine bool   // split expression across multiple lines
+	Brack          string // "", "()", or "[]"
+	Start          Position
+	X              Expr
+	For            []*ForClauseWithIfClausesOpt
+	End
+}
+
+func (x *ListForExpr) Span() (start, end Position) {
+	return x.Start, x.End.Pos.add("]")
+}
+
+// A ForClause represents a for clause in a list comprehension: for Var in Expr.
+type ForClause struct {
+	Comments
+	For  Position
+	Var  []Expr
+	In   Position
+	Expr Expr
+}
+
+func (x *ForClause) Span() (start, end Position) {
+	_, end = x.Expr.Span()
+	return x.For, end
+}
+
+// An IfClause represents an if clause in a list comprehension: if Cond.
+type IfClause struct {
+	Comments
+	If   Position
+	Cond Expr
+}
+
+func (x *IfClause) Span() (start, end Position) {
+	_, end = x.Cond.Span()
+	return x.If, end
+}
+
+// A ForClauseWithIfClausesOpt represents a for clause in a list comprehension followed by optional
+// if expressions: for ... in ... [if ... if ...]
+type ForClauseWithIfClausesOpt struct {
+	Comments
+	For *ForClause
+	Ifs []*IfClause
+}
+
+func (x *ForClauseWithIfClausesOpt) Span() (start, end Position) {
+	start, end = x.For.Span()
+	if len(x.Ifs) > 0 {
+		_, end = x.Ifs[len(x.Ifs)-1].Span()
+	}
+
+	return start, end
+}
+
+// A KeyValueExpr represents a dictionary entry: Key: Value.
+type KeyValueExpr struct {
+	Comments
+	Key   Expr
+	Colon Position
+	Value Expr
+}
+
+func (x *KeyValueExpr) Span() (start, end Position) {
+	start, _ = x.Key.Span()
+	_, end = x.Value.Span()
+	return start, end
+}
+
+// A DictExpr represents a dictionary literal: { List }.
+type DictExpr struct {
+	Comments
+	Start Position
+	List  []Expr   // all *KeyValueExprs
+	Comma Position // position of trailing comma, if any
+	End
+	ForceMultiLine bool // force multiline form when printing
+}
+
+func (x *DictExpr) Span() (start, end Position) {
+	return x.Start, x.End.Pos.add("}")
+}
+
+// A ListExpr represents a list literal: [ List ].
+type ListExpr struct {
+	Comments
+	Start Position
+	List  []Expr
+	Comma Position // position of trailing comma, if any
+	End
+	ForceMultiLine bool // force multiline form when printing
+}
+
+func (x *ListExpr) Span() (start, end Position) {
+	return x.Start, x.End.Pos.add("]")
+}
+
+// A SetExpr represents a set literal: { List }.
+type SetExpr struct {
+	Comments
+	Start Position
+	List  []Expr
+	Comma Position // position of trailing comma, if any
+	End
+	ForceMultiLine bool // force multiline form when printing
+}
+
+func (x *SetExpr) Span() (start, end Position) {
+	return x.Start, x.End.Pos.add("}")
+}
+
+// A TupleExpr represents a tuple literal: (List)
+type TupleExpr struct {
+	Comments
+	Start Position
+	List  []Expr
+	Comma Position // position of trailing comma, if any
+	End
+	ForceCompact   bool // force compact (non-multiline) form when printing
+	ForceMultiLine bool // force multiline form when printing
+}
+
+func (x *TupleExpr) Span() (start, end Position) {
+	return x.Start, x.End.Pos.add(")")
+}
+
+// A UnaryExpr represents a unary expression: Op X.
+type UnaryExpr struct {
+	Comments
+	OpStart Position
+	Op      string
+	X       Expr
+}
+
+func (x *UnaryExpr) Span() (start, end Position) {
+	_, end = x.X.Span()
+	return x.OpStart, end
+}
+
+// A BinaryExpr represents a binary expression: X Op Y.
+type BinaryExpr struct {
+	Comments
+	X         Expr
+	OpStart   Position
+	Op        string
+	LineBreak bool // insert line break between Op and Y
+	Y         Expr
+}
+
+func (x *BinaryExpr) Span() (start, end Position) {
+	start, _ = x.X.Span()
+	_, end = x.Y.Span()
+	return start, end
+}
+
+// A ParenExpr represents a parenthesized expression: (X).
+type ParenExpr struct {
+	Comments
+	Start Position
+	X     Expr
+	End
+	ForceMultiLine bool // insert line break after opening ( and before closing )
+}
+
+func (x *ParenExpr) Span() (start, end Position) {
+	return x.Start, x.End.Pos.add(")")
+}
+
+// A SliceExpr represents a slice expression: X[Y:Z].
+type SliceExpr struct {
+	Comments
+	X          Expr
+	SliceStart Position
+	Y          Expr
+	Colon      Position
+	Z          Expr
+	End        Position
+}
+
+func (x *SliceExpr) Span() (start, end Position) {
+	start, _ = x.X.Span()
+	return start, x.End
+}
+
+// An IndexExpr represents an index expression: X[Y].
+type IndexExpr struct {
+	Comments
+	X          Expr
+	IndexStart Position
+	Y          Expr
+	End        Position
+}
+
+func (x *IndexExpr) Span() (start, end Position) {
+	start, _ = x.X.Span()
+	return start, x.End
+}
+
+// A LambdaExpr represents a lambda expression: lambda Var: Expr.
+type LambdaExpr struct {
+	Comments
+	Lambda Position
+	Var    []Expr
+	Colon  Position
+	Expr   Expr
+}
+
+func (x *LambdaExpr) Span() (start, end Position) {
+	_, end = x.Expr.Span()
+	return x.Lambda, end
+}
+
+// ConditionalExpr represents the conditional: X if TEST else ELSE.
+type ConditionalExpr struct {
+	Comments
+	Then      Expr
+	IfStart   Position
+	Test      Expr
+	ElseStart Position
+	Else      Expr
+}
+
+// Span returns the start and end position of the expression,
+// excluding leading or trailing comments.
+func (x *ConditionalExpr) Span() (start, end Position) {
+	start, _ = x.Then.Span()
+	_, end = x.Else.Span()
+	return start, end
+}

vendor/github.com/bazelbuild/buildtools/build/walk.go

@@ -0,0 +1,132 @@
+/*
+Copyright 2016 Google Inc. All Rights Reserved.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+ WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ See the License for the specific language governing permissions and
+ limitations under the License.
+*/
+
+package build
+
+// Walk walks the expression tree v, calling f on all subexpressions
+// in a preorder traversal.
+//
+// The stk argument is the stack of expressions in the recursion above x,
+// from outermost to innermost.
+//
+func Walk(v Expr, f func(x Expr, stk []Expr)) {
+	var stack []Expr
+	walk1(&v, &stack, func(x Expr, stk []Expr) Expr {
+		f(x, stk)
+		return nil
+	})
+}
+
+// WalkAndUpdate walks the expression tree v, calling f on all subexpressions
+// in a preorder traversal. If f returns a non-nil value, the tree is mutated.
+// The new value replaces the old one.
+//
+// The stk argument is the stack of expressions in the recursion above x,
+// from outermost to innermost.
+//
+func Edit(v Expr, f func(x Expr, stk []Expr) Expr) Expr {
+	var stack []Expr
+	return walk1(&v, &stack, f)
+}
+
+// walk1 is the actual implementation of Walk and WalkAndUpdate.
+// It has the same signature and meaning as Walk,
+// except that it maintains in *stack the current stack
+// of nodes. Using a pointer to a slice here ensures that
+// as the stack grows and shrinks the storage can be
+// reused for the next growth.
+func walk1(v *Expr, stack *[]Expr, f func(x Expr, stk []Expr) Expr) Expr {
+	if v == nil {
+		return nil
+	}
+
+	if res := f(*v, *stack); res != nil {
+		*v = res
+	}
+	*stack = append(*stack, *v)
+	switch v := (*v).(type) {
+	case *File:
+		for _, stmt := range v.Stmt {
+			walk1(&stmt, stack, f)
+		}
+	case *DotExpr:
+		walk1(&v.X, stack, f)
+	case *IndexExpr:
+		walk1(&v.X, stack, f)
+		walk1(&v.Y, stack, f)
+	case *KeyValueExpr:
+		walk1(&v.Key, stack, f)
+		walk1(&v.Value, stack, f)
+	case *SliceExpr:
+		walk1(&v.X, stack, f)
+		if v.Y != nil {
+			walk1(&v.Y, stack, f)
+		}
+		if v.Z != nil {
+			walk1(&v.Z, stack, f)
+		}
+	case *ParenExpr:
+		walk1(&v.X, stack, f)
+	case *UnaryExpr:
+		walk1(&v.X, stack, f)
+	case *BinaryExpr:
+		walk1(&v.X, stack, f)
+		walk1(&v.Y, stack, f)
+	case *LambdaExpr:
+		for i := range v.Var {
+			walk1(&v.Var[i], stack, f)
+		}
+		walk1(&v.Expr, stack, f)
+	case *CallExpr:
+		walk1(&v.X, stack, f)
+		for i := range v.List {
+			walk1(&v.List[i], stack, f)
+		}
+	case *ListExpr:
+		for i := range v.List {
+			walk1(&v.List[i], stack, f)
+		}
+	case *SetExpr:
+		for i := range v.List {
+			walk1(&v.List[i], stack, f)
+		}
+	case *TupleExpr:
+		for i := range v.List {
+			walk1(&v.List[i], stack, f)
+		}
+	case *DictExpr:
+		for i := range v.List {
+			walk1(&v.List[i], stack, f)
+		}
+	case *ListForExpr:
+		walk1(&v.X, stack, f)
+		for _, c := range v.For {
+			for j := range c.For.Var {
+				walk1(&c.For.Var[j], stack, f)
+			}
+			walk1(&c.For.Expr, stack, f)
+			for _, i := range c.Ifs {
+				walk1(&i.Cond, stack, f)
+			}
+		}
+	case *ConditionalExpr:
+		walk1(&v.Then, stack, f)
+		walk1(&v.Test, stack, f)
+		walk1(&v.Else, stack, f)
+	}
+	*stack = (*stack)[:len(*stack)-1]
+	return *v
+}

vendor/github.com/bazelbuild/buildtools/tables/BUILD

@@ -2,8 +2,11 @@ load("@io_bazel_rules_go//go:def.bzl", "go_library")
 
 go_library(
     name = "go_default_library",
-    srcs = ["buffruneio.go"],
-    importpath = "github.com/pelletier/go-buffruneio",
+    srcs = [
+        "jsonparser.go",
+        "tables.go",
+    ],
+    importpath = "github.com/bazelbuild/buildtools/tables",
     visibility = ["//visibility:public"],
 )
 

vendor/github.com/bazelbuild/buildtools/tables/jsonparser.go

@@ -0,0 +1,62 @@
+/*
+Copyright 2017 Google Inc. All Rights Reserved.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+ WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ See the License for the specific language governing permissions and
+ limitations under the License.
+*/
+
+package tables
+
+import (
+	"encoding/json"
+	"io/ioutil"
+)
+
+type Definitions struct {
+	IsLabelArg                      map[string]bool
+	LabelBlacklist                  map[string]bool
+	IsSortableListArg               map[string]bool
+	SortableBlacklist               map[string]bool
+	SortableWhitelist               map[string]bool
+	NamePriority                    map[string]int
+	StripLabelLeadingSlashes        bool
+	ShortenAbsoluteLabelsToRelative bool
+}
+
+// ParseJSONDefinitions reads and parses JSON table definitions from file.
+func ParseJSONDefinitions(file string) (Definitions, error) {
+	var definitions Definitions
+
+	data, err := ioutil.ReadFile(file)
+	if err != nil {
+		return definitions, err
+	}
+
+	err = json.Unmarshal(data, &definitions)
+	return definitions, err
+}
+
+// ParseAndUpdateJSONDefinitions reads definitions from file and merges or
+// overrides the values in memory.
+func ParseAndUpdateJSONDefinitions(file string, merge bool) error {
+	definitions, err := ParseJSONDefinitions(file)
+	if err != nil {
+		return err
+	}
+
+	if merge {
+		MergeTables(definitions.IsLabelArg, definitions.LabelBlacklist, definitions.IsSortableListArg, definitions.SortableBlacklist, definitions.SortableWhitelist, definitions.NamePriority, definitions.StripLabelLeadingSlashes, definitions.ShortenAbsoluteLabelsToRelative)
+	} else {
+		OverrideTables(definitions.IsLabelArg, definitions.LabelBlacklist, definitions.IsSortableListArg, definitions.SortableBlacklist, definitions.SortableWhitelist, definitions.NamePriority, definitions.StripLabelLeadingSlashes, definitions.ShortenAbsoluteLabelsToRelative)
+	}
+	return nil
+}

vendor/github.com/bazelbuild/buildtools/tables/tables.go

@@ -0,0 +1,237 @@
+/*
+Copyright 2016 Google Inc. All Rights Reserved.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+ WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ See the License for the specific language governing permissions and
+ limitations under the License.
+*/
+// Tables about what Buildifier can and cannot edit.
+// Perhaps eventually this will be
+// derived from the BUILD encyclopedia.
+
+package tables
+
+// IsLabelArg: a named argument to a rule call is considered to have a value
+// that can be treated as a label or list of labels if the name
+// is one of these names. There is a separate blacklist for
+// rule-specific exceptions.
+var IsLabelArg = map[string]bool{
+	"app_target":         true,
+	"appdir":             true,
+	"base_package":       true,
+	"build_deps":         true,
+	"cc_deps":            true,
+	"ccdeps":             true,
+	"common_deps":        true,
+	"compile_deps":       true,
+	"compiler":           true,
+	"data":               true,
+	"default_visibility": true,
+	"dep":                true,
+	"deps":               true,
+	"deps_java":          true,
+	"dont_depend_on":     true,
+	"env_deps":           true,
+	"envscripts":         true,
+	"exported_deps":      true,
+	"exports":            true,
+	"externs_list":       true,
+	"files":              true,
+	"globals":            true,
+	"implementation":     true,
+	"implements":         true,
+	"includes":           true,
+	"interface":          true,
+	"jar":                true,
+	"jars":               true,
+	"javadeps":           true,
+	"lib_deps":           true,
+	"library":            true,
+	"malloc":             true,
+	"model":              true,
+	"mods":               true,
+	"module_deps":        true,
+	"module_target":      true,
+	"of":                 true,
+	"plugins":            true,
+	"proto_deps":         true,
+	"proto_target":       true,
+	"protos":             true,
+	"resource":           true,
+	"resources":          true,
+	"runtime_deps":       true,
+	"scope":              true,
+	"shared_deps":        true,
+	"similar_deps":       true,
+	"source_jar":         true,
+	"src":                true,
+	"srcs":               true,
+	"stripped_targets":   true,
+	"suites":             true,
+	"swigdeps":           true,
+	"target":             true,
+	"target_devices":     true,
+	"target_platforms":   true,
+	"template":           true,
+	"test":               true,
+	"tests":              true,
+	"tests_deps":         true,
+	"tool":               true,
+	"tools":              true,
+	"visibility":         true,
+}
+
+// LabelBlacklist is the list of call arguments that cannot be
+// shortened, because they are not interpreted using the same
+// rules as for other labels.
+var LabelBlacklist = map[string]bool{
+	// Shortening this can cause visibility checks to fail.
+	"package_group.includes": true,
+}
+
+// IsSortableListArg: a named argument to a rule call is considered to be a sortable list
+// if the name is one of these names. There is a separate blacklist for
+// rule-specific exceptions.
+var IsSortableListArg = map[string]bool{
+	"cc_deps":             true,
+	"common_deps":         true,
+	"compile_deps":        true,
+	"configs":             true,
+	"constraints":         true,
+	"data":                true,
+	"default_visibility":  true,
+	"deps":                true,
+	"deps_java":           true,
+	"exported_deps":       true,
+	"exports":             true,
+	"filegroups":          true,
+	"files":               true,
+	"hdrs":                true,
+	"imports":             true,
+	"includes":            true,
+	"inherits":            true,
+	"javadeps":            true,
+	"lib_deps":            true,
+	"module_deps":         true,
+	"out":                 true,
+	"outs":                true,
+	"packages":            true,
+	"plugin_modules":      true,
+	"proto_deps":          true,
+	"protos":              true,
+	"pubs":                true,
+	"resources":           true,
+	"runtime_deps":        true,
+	"shared_deps":         true,
+	"similar_deps":        true,
+	"srcs":                true,
+	"swigdeps":            true,
+	"swig_includes":       true,
+	"tags":                true,
+	"tests":               true,
+	"tools":               true,
+	"to_start_extensions": true,
+	"visibility":          true,
+}
+
+// SortableBlacklist records specific rule arguments that must not be reordered.
+var SortableBlacklist = map[string]bool{
+	"genrule.outs": true,
+	"genrule.srcs": true,
+}
+
+// SortableWhitelist records specific rule arguments that are guaranteed
+// to be reorderable, because bazel re-sorts the list itself after reading the BUILD file.
+var SortableWhitelist = map[string]bool{
+	"cc_inc_library.hdrs":      true,
+	"cc_library.hdrs":          true,
+	"java_library.srcs":        true,
+	"java_library.resources":   true,
+	"java_binary.srcs":         true,
+	"java_binary.resources":    true,
+	"java_test.srcs":           true,
+	"java_test.resources":      true,
+	"java_library.constraints": true,
+	"java_import.constraints":  true,
+}
+
+// NamePriority maps an argument name to its sorting priority.
+//
+// NOTE(bazel-team): These are the old buildifier rules. It is likely that this table
+// will change, perhaps swapping in a separate table for each call,
+// derived from the order used in the Build Encyclopedia.
+var NamePriority = map[string]int{
+	"name":              -99,
+	"gwt_name":          -98,
+	"package_name":      -97,
+	"visible_node_name": -96, // for boq_initial_css_modules and boq_jswire_test_suite
+	"size":              -95,
+	"timeout":           -94,
+	"testonly":          -93,
+	"src":               -92,
+	"srcdir":            -91,
+	"srcs":              -90,
+	"out":               -89,
+	"outs":              -88,
+	"hdrs":              -87,
+	"has_services":      -86, // before api versions, for proto
+	"include":           -85, // before exclude, for glob
+	"of":                -84, // for check_dependencies
+	"baseline":          -83, // for searchbox_library
+	// All others sort here, at 0.
+	"destdir":        1,
+	"exports":        2,
+	"runtime_deps":   3,
+	"deps":           4,
+	"implementation": 5,
+	"implements":     6,
+	"alwayslink":     7,
+}
+
+var StripLabelLeadingSlashes = false
+
+var ShortenAbsoluteLabelsToRelative = false
+
+// OverrideTables allows a user of the build package to override the special-case rules. The user-provided tables replace the built-in tables.
+func OverrideTables(labelArg, blacklist, sortableListArg, sortBlacklist, sortWhitelist map[string]bool, namePriority map[string]int, stripLabelLeadingSlashes, shortenAbsoluteLabelsToRelative bool) {
+	IsLabelArg = labelArg
+	LabelBlacklist = blacklist
+	IsSortableListArg = sortableListArg
+	SortableBlacklist = sortBlacklist
+	SortableWhitelist = sortWhitelist
+	NamePriority = namePriority
+	StripLabelLeadingSlashes = stripLabelLeadingSlashes
+	ShortenAbsoluteLabelsToRelative = shortenAbsoluteLabelsToRelative
+}
+
+// MergeTables allows a user of the build package to override the special-case rules. The user-provided tables are merged into the built-in tables.
+func MergeTables(labelArg, blacklist, sortableListArg, sortBlacklist, sortWhitelist map[string]bool, namePriority map[string]int, stripLabelLeadingSlashes, shortenAbsoluteLabelsToRelative bool) {
+	for k, v := range labelArg {
+		IsLabelArg[k] = v
+	}
+	for k, v := range blacklist {
+		LabelBlacklist[k] = v
+	}
+	for k, v := range sortableListArg {
+		IsSortableListArg[k] = v
+	}
+	for k, v := range sortBlacklist {
+		SortableBlacklist[k] = v
+	}
+	for k, v := range sortWhitelist {
+		SortableWhitelist[k] = v
+	}
+	for k, v := range namePriority {
+		NamePriority[k] = v
+	}
+	StripLabelLeadingSlashes = stripLabelLeadingSlashes || StripLabelLeadingSlashes
+	ShortenAbsoluteLabelsToRelative = shortenAbsoluteLabelsToRelative || ShortenAbsoluteLabelsToRelative
+}

vendor/github.com/kubernetes/repo-infra/LICENSE

@@ -0,0 +1,201 @@
+                                 Apache License
+                           Version 2.0, January 2004
+                        http://www.apache.org/licenses/
+
+   TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION
+
+   1. Definitions.
+
+      "License" shall mean the terms and conditions for use, reproduction,
+      and distribution as defined by Sections 1 through 9 of this document.
+
+      "Licensor" shall mean the copyright owner or entity authorized by
+      the copyright owner that is granting the License.
+
+      "Legal Entity" shall mean the union of the acting entity and all
+      other entities that control, are controlled by, or are under common
+      control with that entity. For the purposes of this definition,
+      "control" means (i) the power, direct or indirect, to cause the
+      direction or management of such entity, whether by contract or
+      otherwise, or (ii) ownership of fifty percent (50%) or more of the
+      outstanding shares, or (iii) beneficial ownership of such entity.
+
+      "You" (or "Your") shall mean an individual or Legal Entity
+      exercising permissions granted by this License.
+
+      "Source" form shall mean the preferred form for making modifications,
+      including but not limited to software source code, documentation
+      source, and configuration files.
+
+      "Object" form shall mean any form resulting from mechanical
+      transformation or translation of a Source form, including but
+      not limited to compiled object code, generated documentation,
+      and conversions to other media types.
+
+      "Work" shall mean the work of authorship, whether in Source or
+      Object form, made available under the License, as indicated by a
+      copyright notice that is included in or attached to the work
+      (an example is provided in the Appendix below).
+
+      "Derivative Works" shall mean any work, whether in Source or Object
+      form, that is based on (or derived from) the Work and for which the
+      editorial revisions, annotations, elaborations, or other modifications
+      represent, as a whole, an original work of authorship. For the purposes
+      of this License, Derivative Works shall not include works that remain
+      separable from, or merely link (or bind by name) to the interfaces of,
+      the Work and Derivative Works thereof.
+
+      "Contribution" shall mean any work of authorship, including
+      the original version of the Work and any modifications or additions
+      to that Work or Derivative Works thereof, that is intentionally
+      submitted to Licensor for inclusion in the Work by the copyright owner
+      or by an individual or Legal Entity authorized to submit on behalf of
+      the copyright owner. For the purposes of this definition, "submitted"
+      means any form of electronic, verbal, or written communication sent
+      to the Licensor or its representatives, including but not limited to
+      communication on electronic mailing lists, source code control systems,
+      and issue tracking systems that are managed by, or on behalf of, the
+      Licensor for the purpose of discussing and improving the Work, but
+      excluding communication that is conspicuously marked or otherwise
+      designated in writing by the copyright owner as "Not a Contribution."
+
+      "Contributor" shall mean Licensor and any individual or Legal Entity
+      on behalf of whom a Contribution has been received by Licensor and
+      subsequently incorporated within the Work.
+
+   2. Grant of Copyright License. Subject to the terms and conditions of
+      this License, each Contributor hereby grants to You a perpetual,
+      worldwide, non-exclusive, no-charge, royalty-free, irrevocable
+      copyright license to reproduce, prepare Derivative Works of,
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+      Work and such Derivative Works in Source or Object form.
+
+   3. Grant of Patent License. Subject to the terms and conditions of
+      this License, each Contributor hereby grants to You a perpetual,
+      worldwide, non-exclusive, no-charge, royalty-free, irrevocable
+      (except as stated in this section) patent license to make, have made,
+      use, offer to sell, sell, import, and otherwise transfer the Work,
+      where such license applies only to those patent claims licensable
+      by such Contributor that are necessarily infringed by their
+      Contribution(s) alone or by combination of their Contribution(s)
+      with the Work to which such Contribution(s) was submitted. If You
+      institute patent litigation against any entity (including a
+      cross-claim or counterclaim in a lawsuit) alleging that the Work
+      or a Contribution incorporated within the Work constitutes direct
+      or contributory patent infringement, then any patent licenses
+      granted to You under this License for that Work shall terminate
+      as of the date such litigation is filed.
+
+   4. Redistribution. You may reproduce and distribute copies of the
+      Work or Derivative Works thereof in any medium, with or without
+      modifications, and in Source or Object form, provided that You
+      meet the following conditions:
+
+      (a) You must give any other recipients of the Work or
+          Derivative Works a copy of this License; and
+
+      (b) You must cause any modified files to carry prominent notices
+          stating that You changed the files; and
+
+      (c) You must retain, in the Source form of any Derivative Works
+          that You distribute, all copyright, patent, trademark, and
+          attribution notices from the Source form of the Work,
+          excluding those notices that do not pertain to any part of
+          the Derivative Works; and
+
+      (d) If the Work includes a "NOTICE" text file as part of its
+          distribution, then any Derivative Works that You distribute must
+          include a readable copy of the attribution notices contained
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+          pertain to any part of the Derivative Works, in at least one
+          of the following places: within a NOTICE text file distributed
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+          of the NOTICE file are for informational purposes only and
+          do not modify the License. You may add Your own attribution
+          notices within Derivative Works that You distribute, alongside
+          or as an addendum to the NOTICE text from the Work, provided
+          that such additional attribution notices cannot be construed
+          as modifying the License.
+
+      You may add Your own copyright statement to Your modifications and
+      may provide additional or different license terms and conditions
+      for use, reproduction, or distribution of Your modifications, or
+      for any such Derivative Works as a whole, provided Your use,
+      reproduction, and distribution of the Work otherwise complies with
+      the conditions stated in this License.
+
+   5. Submission of Contributions. Unless You explicitly state otherwise,
+      any Contribution intentionally submitted for inclusion in the Work
+      by You to the Licensor shall be under the terms and conditions of
+      this License, without any additional terms or conditions.
+      Notwithstanding the above, nothing herein shall supersede or modify
+      the terms of any separate license agreement you may have executed
+      with Licensor regarding such Contributions.
+
+   6. Trademarks. This License does not grant permission to use the trade
+      names, trademarks, service marks, or product names of the Licensor,
+      except as required for reasonable and customary use in describing the
+      origin of the Work and reproducing the content of the NOTICE file.
+
+   7. Disclaimer of Warranty. Unless required by applicable law or
+      agreed to in writing, Licensor provides the Work (and each
+      Contributor provides its Contributions) on an "AS IS" BASIS,
+      WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
+      implied, including, without limitation, any warranties or conditions
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+      PARTICULAR PURPOSE. You are solely responsible for determining the
+      appropriateness of using or redistributing the Work and assume any
+      risks associated with Your exercise of permissions under this License.
+
+   8. Limitation of Liability. In no event and under no legal theory,
+      whether in tort (including negligence), contract, or otherwise,
+      unless required by applicable law (such as deliberate and grossly
+      negligent acts) or agreed to in writing, shall any Contributor be
+      liable to You for damages, including any direct, indirect, special,
+      incidental, or consequential damages of any character arising as a
+      result of this License or out of the use or inability to use the
+      Work (including but not limited to damages for loss of goodwill,
+      work stoppage, computer failure or malfunction, or any and all
+      other commercial damages or losses), even if such Contributor
+      has been advised of the possibility of such damages.
+
+   9. Accepting Warranty or Additional Liability. While redistributing
+      the Work or Derivative Works thereof, You may choose to offer,
+      and charge a fee for, acceptance of support, warranty, indemnity,
+      or other liability obligations and/or rights consistent with this
+      License. However, in accepting such obligations, You may act only
+      on Your own behalf and on Your sole responsibility, not on behalf
+      of any other Contributor, and only if You agree to indemnify,
+      defend, and hold each Contributor harmless for any liability
+      incurred by, or claims asserted against, such Contributor by reason
+      of your accepting any such warranty or additional liability.
+
+   END OF TERMS AND CONDITIONS
+
+   APPENDIX: How to apply the Apache License to your work.
+
+      To apply the Apache License to your work, attach the following
+      boilerplate notice, with the fields enclosed by brackets "{}"
+      replaced with your own identifying information. (Don't include
+      the brackets!)  The text should be enclosed in the appropriate
+      comment syntax for the file format. We also recommend that a
+      file or class name and description of purpose be included on the
+      same "printed page" as the copyright notice for easier
+      identification within third-party archives.
+
+   Copyright {yyyy} {name of copyright owner}
+
+   Licensed under the Apache License, Version 2.0 (the "License");
+   you may not use this file except in compliance with the License.
+   You may obtain a copy of the License at
+
+       http://www.apache.org/licenses/LICENSE-2.0
+
+   Unless required by applicable law or agreed to in writing, software
+   distributed under the License is distributed on an "AS IS" BASIS,
+   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+   See the License for the specific language governing permissions and
+   limitations under the License.

vendor/github.com/kubernetes/repo-infra/kazel/BUILD

@@ -0,0 +1,46 @@
+package(default_visibility = ["//visibility:public"])
+
+licenses(["notice"])
+
+load(
+    "@io_bazel_rules_go//go:def.bzl",
+    "go_binary",
+    "go_library",
+)
+
+go_binary(
+    name = "kazel",
+    embed = [":go_default_library"],
+    tags = ["automanaged"],
+)
+
+go_library(
+    name = "go_default_library",
+    srcs = [
+        "config.go",
+        "diff.go",
+        "generator.go",
+        "kazel.go",
+        "sourcerer.go",
+    ],
+    importpath = "github.com/kubernetes/repo-infra/kazel",
+    tags = ["automanaged"],
+    deps = [
+        "//vendor/github.com/bazelbuild/buildtools/build:go_default_library",
+        "//vendor/github.com/golang/glog:go_default_library",
+    ],
+)
+
+filegroup(
+    name = "package-srcs",
+    srcs = glob(["**"]),
+    tags = ["automanaged"],
+    visibility = ["//visibility:private"],
+)
+
+filegroup(
+    name = "all-srcs",
+    srcs = [":package-srcs"],
+    tags = ["automanaged"],
+    visibility = ["//visibility:public"],
+)

vendor/github.com/kubernetes/repo-infra/kazel/README.rst

@@ -0,0 +1,90 @@
+kazel - a BUILD file generator for go and bazel
+===============================================
+
+Requirements:
+#############
+
+* Your project must be somewhat compatible with go tool because
+  kazel uses go tool to parse your import tree.
+* You must have a **GOPATH** and **GOROOT** setup and your project must
+  be in the correct location in your **GOPATH**.
+* Your ``./vendor`` directory may not contain ``BUILD`` files.
+
+Usage:
+######
+
+1. Get kazel by running ``go get k8s.io/repo-infra/kazel``.
+
+2. Create a ``.kazelcfg.json`` in the root of the repository. For the
+   kazel repository, the ``.kazelcfg.json`` would look like:
+
+  .. code-block:: json
+
+   {
+     "GoPrefix": "k8s.io/repo-infra",
+     "SrcDirs": [
+       "./kazel"
+     ],
+     "SkippedPaths": [
+       ".*foobar(baz)?.*$"
+     ]
+   }
+
+3. Run kazel:
+
+  .. code-block:: bash
+
+    $ kazel -root=$GOPATH/src/k8s.io/repo-infra
+
+Defaults:
+#########
+
+* **SrcDirs** in ``.kazelcfg.json`` defaults to ``["./"]``
+* ``-root`` option defaults to the current working directory
+
+Automanagement:
+###############
+
+kazel reconciles rules that have the "**automanaged**" tag. If
+you no longer want kazel to manage a rule, you can remove the
+**automanaged** tag and kazel will no longer manage that rule.
+
+kazel only manages srcs, deps, and library attributes of a
+rule after initial creation so you can add and managed other
+attributes like data and copts and kazel will respect your
+changes.
+
+kazel automatically formats all ``BUILD`` files in your repository
+except for those matching **SkippedPaths**.
+
+Adding "sources" rules:
+#######################
+
+If you set "**AddSourcesRules**": ``true`` in your ``.kazelcfg.json``,
+kazel will create "**package-srcs**" and "**all-srcs**" rules in every
+package.
+
+The "**package-srcs**" rule is a glob matching all files in the
+package recursively, but not any files owned by packages in
+subdirectories.
+
+The "**all-srcs**" rule includes both the "**package-srcs**" rule and
+the "**all-srcs**" rules of all subpackages; i.e. **//:all-srcs** will
+include all files in your repository.
+
+The "**package-srcs**" rule defaults to private visibility,
+since it is safer to depend on the "**all-srcs**" rule: if a
+subpackage is added, the "**package-srcs**" rule will no longer
+include those files.
+
+You can remove the "**automanaged**" tag from the "**package-srcs**"
+rule if you need to modify the glob (such as adding excludes).
+It's recommended that you leave the "**all-srcs**" rule
+automanaged.
+
+Validating BUILD files in CI:
+#############################
+
+If you run kazel with ``--validate``, it will not update any ``BUILD`` files, but it
+will exit nonzero if any ``BUILD`` files are out-of-date. You can add ``--print-diff``
+to print out the changes needed.

vendor/github.com/kubernetes/repo-infra/kazel/config.go

@@ -0,0 +1,61 @@
+/*
+Copyright 2017 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package main
+
+import (
+	"encoding/json"
+	"io/ioutil"
+)
+
+// Cfg defines the configuration options for kazel.
+type Cfg struct {
+	GoPrefix string
+	// evaluated recursively, defaults to ["."]
+	SrcDirs []string
+	// regexps that match packages to skip
+	SkippedPaths []string
+	// whether to add "pkg-srcs" and "all-srcs" filegroups
+	// note that this operates on the entire tree (not just SrcsDirs) but skips anything matching SkippedPaths
+	AddSourcesRules bool
+	// whether to have multiple build files in vendor/ or just one.
+	VendorMultipleBuildFiles bool
+	// whether to manage kubernetes' pkg/generated/openapi.
+	K8sOpenAPIGen bool
+	// Whether to manage the upstream Go rules provided by bazelbuild/rules_go.
+	// If using gazelle, set this to false (or omit).
+	ManageGoRules bool
+}
+
+// ReadCfg reads and unmarshals the specified json file into a Cfg struct.
+func ReadCfg(cfgPath string) (*Cfg, error) {
+	b, err := ioutil.ReadFile(cfgPath)
+	if err != nil {
+		return nil, err
+	}
+	var cfg Cfg
+	if err := json.Unmarshal(b, &cfg); err != nil {
+		return nil, err
+	}
+	defaultCfg(&cfg)
+	return &cfg, nil
+}
+
+func defaultCfg(c *Cfg) {
+	if len(c.SrcDirs) == 0 {
+		c.SrcDirs = []string{"."}
+	}
+}

vendor/github.com/kubernetes/repo-infra/kazel/diff.go

@@ -0,0 +1,60 @@
+/*
+Copyright 2017 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package main
+
+import (
+	"io/ioutil"
+	"os"
+	"os/exec"
+)
+
+// Diff prints the unified diff of the two provided byte slices
+// using the unix diff command.
+func Diff(left, right []byte) error {
+	lf, err := ioutil.TempFile("/tmp", "actual-file-")
+	if err != nil {
+		return err
+	}
+	defer lf.Close()
+	defer os.Remove(lf.Name())
+
+	rf, err := ioutil.TempFile("/tmp", "expected-file-")
+	if err != nil {
+		return err
+	}
+	defer rf.Close()
+	defer os.Remove(rf.Name())
+
+	_, err = lf.Write(left)
+	if err != nil {
+		return err
+	}
+	lf.Close()
+
+	_, err = rf.Write(right)
+	if err != nil {
+		return err
+	}
+	rf.Close()
+
+	cmd := exec.Command("/usr/bin/diff", "-u", lf.Name(), rf.Name())
+	cmd.Stdout = os.Stdout
+	cmd.Stderr = os.Stderr
+	cmd.Run()
+
+	return nil
+}

vendor/github.com/kubernetes/repo-infra/kazel/generator.go

@@ -0,0 +1,128 @@
+/*
+Copyright 2017 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package main
+
+import (
+	"bytes"
+	"fmt"
+	"io/ioutil"
+	"os"
+	"path/filepath"
+	"sort"
+	"strings"
+)
+
+const (
+	openAPIGenTag = "// +k8s:openapi-gen"
+
+	staging = "staging/src/"
+)
+
+// walkGenerated updates the rule for kubernetes' OpenAPI generated file.
+// This involves reading all go files in the source tree and looking for the
+// "+k8s:openapi-gen" tag. If present, then that package must be supplied to
+// the genrule.
+func (v *Vendorer) walkGenerated() error {
+	if !v.cfg.K8sOpenAPIGen {
+		return nil
+	}
+	v.managedAttrs = append(v.managedAttrs, "openapi_targets", "vendor_targets")
+	paths, err := v.findOpenAPI(".")
+	if err != nil {
+		return err
+	}
+	return v.addGeneratedOpenAPIRule(paths)
+}
+
+// findOpenAPI searches for all packages under root that request OpenAPI. It
+// returns the go import paths. It does not follow symlinks.
+func (v *Vendorer) findOpenAPI(root string) ([]string, error) {
+	for _, r := range v.skippedPaths {
+		if r.MatchString(root) {
+			return nil, nil
+		}
+	}
+	finfos, err := ioutil.ReadDir(root)
+	if err != nil {
+		return nil, err
+	}
+	var res []string
+	var includeMe bool
+	for _, finfo := range finfos {
+		path := filepath.Join(root, finfo.Name())
+		if finfo.IsDir() && (finfo.Mode()&os.ModeSymlink == 0) {
+			children, err := v.findOpenAPI(path)
+			if err != nil {
+				return nil, err
+			}
+			res = append(res, children...)
+		} else if strings.HasSuffix(path, ".go") && !strings.HasSuffix(path, "_test.go") {
+			b, err := ioutil.ReadFile(path)
+			if err != nil {
+				return nil, err
+			}
+			if bytes.Contains(b, []byte(openAPIGenTag)) {
+				includeMe = true
+			}
+		}
+	}
+	if includeMe {
+		pkg, err := v.ctx.ImportDir(filepath.Join(v.root, root), 0)
+		if err != nil {
+			return nil, err
+		}
+		res = append(res, pkg.ImportPath)
+	}
+	return res, nil
+}
+
+// addGeneratedOpenAPIRule updates the pkg/generated/openapi go_default_library
+// rule with the automanaged openapi_targets and vendor_targets.
+func (v *Vendorer) addGeneratedOpenAPIRule(paths []string) error {
+	var openAPITargets []string
+	var vendorTargets []string
+	baseImport := v.cfg.GoPrefix + "/"
+	for _, p := range paths {
+		if !strings.HasPrefix(p, baseImport) {
+			return fmt.Errorf("openapi-gen path outside of %s: %s", v.cfg.GoPrefix, p)
+		}
+		np := p[len(baseImport):]
+		if strings.HasPrefix(np, staging) {
+			vendorTargets = append(vendorTargets, np[len(staging):])
+		} else {
+			openAPITargets = append(openAPITargets, np)
+		}
+	}
+	sort.Strings(openAPITargets)
+	sort.Strings(vendorTargets)
+
+	pkgPath := filepath.Join("pkg", "generated", "openapi")
+	// If we haven't walked this package yet, walk it so there is a go_library rule to modify
+	if len(v.newRules[pkgPath]) == 0 {
+		if err := v.updateSinglePkg(pkgPath); err != nil {
+			return err
+		}
+	}
+	for _, r := range v.newRules[pkgPath] {
+		if r.Name() == "go_default_library" {
+			r.SetAttr("openapi_targets", asExpr(openAPITargets))
+			r.SetAttr("vendor_targets", asExpr(vendorTargets))
+			break
+		}
+	}
+	return nil
+}

vendor/github.com/kubernetes/repo-infra/kazel/kazel.go

@@ -0,0 +1,784 @@
+/*
+Copyright 2017 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package main
+
+import (
+	"bytes"
+	"flag"
+	"fmt"
+	"go/build"
+	"io/ioutil"
+	"os"
+	"path/filepath"
+	"reflect"
+	"regexp"
+	"runtime"
+	"sort"
+	"strings"
+
+	bzl "github.com/bazelbuild/buildtools/build"
+	"github.com/golang/glog"
+)
+
+const (
+	vendorPath     = "vendor/"
+	automanagedTag = "automanaged"
+)
+
+var (
+	root      = flag.String("root", ".", "root of go source")
+	dryRun    = flag.Bool("dry-run", false, "run in dry mode")
+	printDiff = flag.Bool("print-diff", false, "print diff to stdout")
+	validate  = flag.Bool("validate", false, "run in dry mode and exit nonzero if any BUILD files need to be updated")
+	cfgPath   = flag.String("cfg-path", ".kazelcfg.json", "path to kazel config (relative paths interpreted relative to -repo.")
+)
+
+func main() {
+	flag.Parse()
+	flag.Set("alsologtostderr", "true")
+	if *root == "" {
+		glog.Fatalf("-root argument is required")
+	}
+	if *validate {
+		*dryRun = true
+	}
+	v, err := newVendorer(*root, *cfgPath, *dryRun)
+	if err != nil {
+		glog.Fatalf("unable to build vendorer: %v", err)
+	}
+	if err = os.Chdir(v.root); err != nil {
+		glog.Fatalf("cannot chdir into root %q: %v", v.root, err)
+	}
+
+	if v.cfg.ManageGoRules {
+		if err = v.walkVendor(); err != nil {
+			glog.Fatalf("err walking vendor: %v", err)
+		}
+		if err = v.walkRepo(); err != nil {
+			glog.Fatalf("err walking repo: %v", err)
+		}
+	}
+	if err = v.walkGenerated(); err != nil {
+		glog.Fatalf("err walking generated: %v", err)
+	}
+	if _, err = v.walkSource("."); err != nil {
+		glog.Fatalf("err walking source: %v", err)
+	}
+	written := 0
+	if written, err = v.reconcileAllRules(); err != nil {
+		glog.Fatalf("err reconciling rules: %v", err)
+	}
+	if *validate && written > 0 {
+		fmt.Fprintf(os.Stderr, "\n%d BUILD files not up-to-date.\n", written)
+		os.Exit(1)
+	}
+}
+
+// Vendorer collects context, configuration, and cache while walking the tree.
+type Vendorer struct {
+	ctx          *build.Context
+	icache       map[icacheKey]icacheVal
+	skippedPaths []*regexp.Regexp
+	dryRun       bool
+	root         string
+	cfg          *Cfg
+	newRules     map[string][]*bzl.Rule // package path -> list of rules to add or update
+	managedAttrs []string
+}
+
+func newVendorer(root, cfgPath string, dryRun bool) (*Vendorer, error) {
+	absRoot, err := filepath.Abs(root)
+	if err != nil {
+		return nil, fmt.Errorf("could not get absolute path: %v", err)
+	}
+	if !filepath.IsAbs(cfgPath) {
+		cfgPath = filepath.Join(absRoot, cfgPath)
+	}
+	cfg, err := ReadCfg(cfgPath)
+	if err != nil {
+		return nil, err
+	}
+
+	v := Vendorer{
+		ctx:          context(),
+		dryRun:       dryRun,
+		root:         absRoot,
+		icache:       map[icacheKey]icacheVal{},
+		cfg:          cfg,
+		newRules:     make(map[string][]*bzl.Rule),
+		managedAttrs: []string{"srcs", "deps", "library"},
+	}
+
+	for _, sp := range cfg.SkippedPaths {
+		r, err := regexp.Compile(sp)
+		if err != nil {
+			return nil, err
+		}
+		v.skippedPaths = append(v.skippedPaths, r)
+	}
+	for _, builtinSkip := range []string{
+		"^\\.git",
+		"^bazel-*",
+	} {
+		v.skippedPaths = append(v.skippedPaths, regexp.MustCompile(builtinSkip))
+	}
+
+	return &v, nil
+
+}
+
+type icacheKey struct {
+	path, srcDir string
+}
+
+type icacheVal struct {
+	pkg *build.Package
+	err error
+}
+
+func (v *Vendorer) importPkg(path string, srcDir string) (*build.Package, error) {
+	k := icacheKey{path: path, srcDir: srcDir}
+	if val, ok := v.icache[k]; ok {
+		return val.pkg, val.err
+	}
+
+	// cache miss
+	pkg, err := v.ctx.Import(path, srcDir, build.ImportComment)
+	v.icache[k] = icacheVal{pkg: pkg, err: err}
+	return pkg, err
+}
+
+func writeHeaders(file *bzl.File) {
+	pkgRule := bzl.Rule{
+		Call: &bzl.CallExpr{
+			X: &bzl.LiteralExpr{Token: "package"},
+		},
+	}
+	pkgRule.SetAttr("default_visibility", asExpr([]string{"//visibility:public"}))
+
+	file.Stmt = append(file.Stmt,
+		[]bzl.Expr{
+			pkgRule.Call,
+			&bzl.CallExpr{
+				X: &bzl.LiteralExpr{Token: "load"},
+				List: asExpr([]string{
+					"@io_bazel_rules_go//go:def.bzl",
+				}).(*bzl.ListExpr).List,
+			},
+		}...,
+	)
+}
+
+func writeRules(file *bzl.File, rules []*bzl.Rule) {
+	for _, rule := range rules {
+		file.Stmt = append(file.Stmt, rule.Call)
+	}
+}
+
+func (v *Vendorer) resolve(ipath string) Label {
+	if ipath == v.cfg.GoPrefix {
+		return Label{
+			tag: "go_default_library",
+		}
+	} else if strings.HasPrefix(ipath, v.cfg.GoPrefix) {
+		return Label{
+			pkg: strings.TrimPrefix(ipath, v.cfg.GoPrefix+"/"),
+			tag: "go_default_library",
+		}
+	}
+	if v.cfg.VendorMultipleBuildFiles {
+		return Label{
+			pkg: "vendor/" + ipath,
+			tag: "go_default_library",
+		}
+	}
+	return Label{
+		pkg: "vendor",
+		tag: ipath,
+	}
+}
+
+func (v *Vendorer) walk(root string, f func(path, ipath string, pkg *build.Package) error) error {
+	skipVendor := true
+	if root == vendorPath {
+		skipVendor = false
+	}
+	return filepath.Walk(root, func(path string, info os.FileInfo, err error) error {
+		if err != nil {
+			return err
+		}
+		if !info.IsDir() {
+			return nil
+		}
+		if skipVendor && strings.HasPrefix(path, vendorPath) {
+			return filepath.SkipDir
+		}
+		for _, r := range v.skippedPaths {
+			if r.MatchString(path) {
+				return filepath.SkipDir
+			}
+		}
+		ipath, err := filepath.Rel(root, path)
+		if err != nil {
+			return err
+		}
+		pkg, err := v.importPkg(".", filepath.Join(v.root, path))
+		if err != nil {
+			if _, ok := err.(*build.NoGoError); err != nil && ok {
+				return nil
+			}
+			return err
+		}
+
+		return f(path, ipath, pkg)
+	})
+}
+
+func (v *Vendorer) walkRepo() error {
+	for _, root := range v.cfg.SrcDirs {
+		if err := v.walk(root, v.updatePkg); err != nil {
+			return err
+		}
+	}
+	return nil
+}
+
+func (v *Vendorer) updateSinglePkg(path string) error {
+	pkg, err := v.importPkg(".", "./"+path)
+	if err != nil {
+		if _, ok := err.(*build.NoGoError); err != nil && ok {
+			return nil
+		}
+		return err
+	}
+	return v.updatePkg(path, "", pkg)
+}
+
+type ruleType int
+
+// The RuleType* constants enumerate the bazel rules supported by this tool.
+const (
+	RuleTypeGoBinary ruleType = iota
+	RuleTypeGoLibrary
+	RuleTypeGoTest
+	RuleTypeGoXTest
+	RuleTypeCGoGenrule
+	RuleTypeFileGroup
+	RuleTypeOpenAPILibrary
+)
+
+// RuleKind converts a value of the RuleType* enum into the BUILD string.
+func (rt ruleType) RuleKind() string {
+	switch rt {
+	case RuleTypeGoBinary:
+		return "go_binary"
+	case RuleTypeGoLibrary:
+		return "go_library"
+	case RuleTypeGoTest:
+		return "go_test"
+	case RuleTypeGoXTest:
+		return "go_test"
+	case RuleTypeCGoGenrule:
+		return "cgo_genrule"
+	case RuleTypeFileGroup:
+		return "filegroup"
+	case RuleTypeOpenAPILibrary:
+		return "openapi_library"
+	}
+	panic("unreachable")
+}
+
+// NamerFunc is a function that returns the appropriate name for the rule for the provided RuleType.
+type NamerFunc func(ruleType) string
+
+func (v *Vendorer) updatePkg(path, _ string, pkg *build.Package) error {
+
+	srcNameMap := func(srcs ...[]string) *bzl.ListExpr {
+		return asExpr(merge(srcs...)).(*bzl.ListExpr)
+	}
+
+	srcs := srcNameMap(pkg.GoFiles, pkg.SFiles)
+	cgoSrcs := srcNameMap(pkg.CgoFiles, pkg.CFiles, pkg.CXXFiles, pkg.HFiles)
+	testSrcs := srcNameMap(pkg.TestGoFiles)
+	xtestSrcs := srcNameMap(pkg.XTestGoFiles)
+
+	v.addRules(path, v.emit(srcs, cgoSrcs, testSrcs, xtestSrcs, pkg, func(rt ruleType) string {
+		switch rt {
+		case RuleTypeGoBinary:
+			return filepath.Base(pkg.Dir)
+		case RuleTypeGoLibrary:
+			return "go_default_library"
+		case RuleTypeGoTest:
+			return "go_default_test"
+		case RuleTypeGoXTest:
+			return "go_default_xtest"
+		case RuleTypeCGoGenrule:
+			return "cgo_codegen"
+		}
+		panic("unreachable")
+	}))
+
+	return nil
+}
+
+func (v *Vendorer) emit(srcs, cgoSrcs, testSrcs, xtestSrcs *bzl.ListExpr, pkg *build.Package, namer NamerFunc) []*bzl.Rule {
+	var goLibAttrs = make(Attrs)
+	var rules []*bzl.Rule
+
+	deps := v.extractDeps(pkg.Imports)
+
+	if len(srcs.List) >= 0 {
+		goLibAttrs.Set("srcs", srcs)
+	} else if len(cgoSrcs.List) == 0 {
+		return nil
+	}
+
+	if len(deps.List) > 0 {
+		goLibAttrs.SetList("deps", deps)
+	}
+
+	if pkg.IsCommand() {
+		rules = append(rules, newRule(RuleTypeGoBinary, namer, map[string]bzl.Expr{
+			"library": asExpr(":" + namer(RuleTypeGoLibrary)),
+		}))
+	}
+
+	addGoDefaultLibrary := len(cgoSrcs.List) > 0 || len(srcs.List) > 0
+	if len(cgoSrcs.List) != 0 {
+		cgoRuleAttrs := make(Attrs)
+
+		cgoRuleAttrs.SetList("srcs", cgoSrcs)
+		cgoRuleAttrs.SetList("clinkopts", asExpr([]string{"-lz", "-lm", "-lpthread", "-ldl"}).(*bzl.ListExpr))
+
+		rules = append(rules, newRule(RuleTypeCGoGenrule, namer, cgoRuleAttrs))
+
+		goLibAttrs.Set("library", asExpr(":"+namer(RuleTypeCGoGenrule)))
+	}
+
+	if len(testSrcs.List) != 0 {
+		testRuleAttrs := make(Attrs)
+
+		testRuleAttrs.SetList("srcs", testSrcs)
+		testRuleAttrs.SetList("deps", v.extractDeps(pkg.TestImports))
+
+		if addGoDefaultLibrary {
+			testRuleAttrs.Set("library", asExpr(":"+namer(RuleTypeGoLibrary)))
+		}
+		rules = append(rules, newRule(RuleTypeGoTest, namer, testRuleAttrs))
+	}
+
+	if addGoDefaultLibrary {
+		rules = append(rules, newRule(RuleTypeGoLibrary, namer, goLibAttrs))
+	}
+
+	if len(xtestSrcs.List) != 0 {
+		xtestRuleAttrs := make(Attrs)
+
+		xtestRuleAttrs.SetList("srcs", xtestSrcs)
+		xtestRuleAttrs.SetList("deps", v.extractDeps(pkg.XTestImports))
+
+		rules = append(rules, newRule(RuleTypeGoXTest, namer, xtestRuleAttrs))
+	}
+
+	return rules
+}
+
+func (v *Vendorer) addRules(pkgPath string, rules []*bzl.Rule) {
+	cleanPath := filepath.Clean(pkgPath)
+	v.newRules[cleanPath] = append(v.newRules[cleanPath], rules...)
+}
+
+func (v *Vendorer) walkVendor() error {
+	var rules []*bzl.Rule
+	updateFunc := func(path, ipath string, pkg *build.Package) error {
+		srcNameMap := func(srcs ...[]string) *bzl.ListExpr {
+			return asExpr(
+				apply(
+					merge(srcs...),
+					mapper(func(s string) string {
+						return strings.TrimPrefix(filepath.Join(path, s), "vendor/")
+					}),
+				),
+			).(*bzl.ListExpr)
+		}
+
+		srcs := srcNameMap(pkg.GoFiles, pkg.SFiles)
+		cgoSrcs := srcNameMap(pkg.CgoFiles, pkg.CFiles, pkg.CXXFiles, pkg.HFiles)
+		testSrcs := srcNameMap(pkg.TestGoFiles)
+		xtestSrcs := srcNameMap(pkg.XTestGoFiles)
+
+		tagBase := v.resolve(ipath).tag
+
+		rules = append(rules, v.emit(srcs, cgoSrcs, testSrcs, xtestSrcs, pkg, func(rt ruleType) string {
+			switch rt {
+			case RuleTypeGoBinary:
+				return tagBase + "_bin"
+			case RuleTypeGoLibrary:
+				return tagBase
+			case RuleTypeGoTest:
+				return tagBase + "_test"
+			case RuleTypeGoXTest:
+				return tagBase + "_xtest"
+			case RuleTypeCGoGenrule:
+				return tagBase + "_cgo"
+			}
+			panic("unreachable")
+		})...)
+
+		return nil
+	}
+	if v.cfg.VendorMultipleBuildFiles {
+		updateFunc = v.updatePkg
+	}
+	if err := v.walk(vendorPath, updateFunc); err != nil {
+		return err
+	}
+	v.addRules(vendorPath, rules)
+
+	return nil
+}
+
+func (v *Vendorer) extractDeps(deps []string) *bzl.ListExpr {
+	return asExpr(
+		apply(
+			merge(deps),
+			filterer(func(s string) bool {
+				pkg, err := v.importPkg(s, v.root)
+				if err != nil {
+					if strings.Contains(err.Error(), `cannot find package "C"`) ||
+						// added in go1.7
+						strings.Contains(err.Error(), `cannot find package "context"`) ||
+						strings.Contains(err.Error(), `cannot find package "net/http/httptrace"`) {
+						return false
+					}
+					fmt.Fprintf(os.Stderr, "extract err: %v\n", err)
+					return false
+				}
+				if pkg.Goroot {
+					return false
+				}
+				return true
+			}),
+			mapper(func(s string) string {
+				return v.resolve(s).String()
+			}),
+		),
+	).(*bzl.ListExpr)
+}
+
+func (v *Vendorer) reconcileAllRules() (int, error) {
+	var paths []string
+	for path := range v.newRules {
+		paths = append(paths, path)
+	}
+	sort.Strings(paths)
+	written := 0
+	for _, path := range paths {
+		w, err := ReconcileRules(path, v.newRules[path], v.managedAttrs, v.dryRun, v.cfg.ManageGoRules)
+		if w {
+			written++
+		}
+		if err != nil {
+			return written, err
+		}
+	}
+	return written, nil
+}
+
+// Attrs collects the attributes for a rule.
+type Attrs map[string]bzl.Expr
+
+// Set sets the named attribute to the provided bazel expression.
+func (a Attrs) Set(name string, expr bzl.Expr) {
+	a[name] = expr
+}
+
+// SetList sets the named attribute to the provided bazel expression list.
+func (a Attrs) SetList(name string, expr *bzl.ListExpr) {
+	if len(expr.List) == 0 {
+		return
+	}
+	a[name] = expr
+}
+
+// Label defines a bazel label.
+type Label struct {
+	pkg, tag string
+}
+
+func (l Label) String() string {
+	return fmt.Sprintf("//%v:%v", l.pkg, l.tag)
+}
+
+func asExpr(e interface{}) bzl.Expr {
+	rv := reflect.ValueOf(e)
+	switch rv.Kind() {
+	case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64,
+		reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64:
+		return &bzl.LiteralExpr{Token: fmt.Sprintf("%d", e)}
+	case reflect.Float32, reflect.Float64:
+		return &bzl.LiteralExpr{Token: fmt.Sprintf("%f", e)}
+	case reflect.String:
+		return &bzl.StringExpr{Value: e.(string)}
+	case reflect.Slice, reflect.Array:
+		var list []bzl.Expr
+		for i := 0; i < rv.Len(); i++ {
+			list = append(list, asExpr(rv.Index(i).Interface()))
+		}
+		return &bzl.ListExpr{List: list}
+	default:
+		glog.Fatalf("Uh oh")
+		return nil
+	}
+}
+
+type sed func(s []string) []string
+
+func mapString(in []string, f func(string) string) []string {
+	var out []string
+	for _, s := range in {
+		out = append(out, f(s))
+	}
+	return out
+}
+
+func mapper(f func(string) string) sed {
+	return func(in []string) []string {
+		return mapString(in, f)
+	}
+}
+
+func filterString(in []string, f func(string) bool) []string {
+	var out []string
+	for _, s := range in {
+		if f(s) {
+			out = append(out, s)
+		}
+	}
+	return out
+}
+
+func filterer(f func(string) bool) sed {
+	return func(in []string) []string {
+		return filterString(in, f)
+	}
+}
+
+func apply(stream []string, seds ...sed) []string {
+	for _, sed := range seds {
+		stream = sed(stream)
+	}
+	return stream
+}
+
+func merge(streams ...[]string) []string {
+	var out []string
+	for _, stream := range streams {
+		out = append(out, stream...)
+	}
+	return out
+}
+
+func newRule(rt ruleType, namer NamerFunc, attrs map[string]bzl.Expr) *bzl.Rule {
+	rule := &bzl.Rule{
+		Call: &bzl.CallExpr{
+			X: &bzl.LiteralExpr{Token: rt.RuleKind()},
+		},
+	}
+	rule.SetAttr("name", asExpr(namer(rt)))
+	for k, v := range attrs {
+		rule.SetAttr(k, v)
+	}
+	rule.SetAttr("tags", asExpr([]string{automanagedTag}))
+	return rule
+}
+
+// findBuildFile determines the name of a preexisting BUILD file, returning
+// a default if no such file exists.
+func findBuildFile(pkgPath string) (bool, string) {
+	options := []string{"BUILD.bazel", "BUILD"}
+	for _, b := range options {
+		path := filepath.Join(pkgPath, b)
+		info, err := os.Stat(path)
+		if err == nil && !info.IsDir() {
+			return true, path
+		}
+	}
+	return false, filepath.Join(pkgPath, "BUILD")
+}
+
+// ReconcileRules reconciles, simplifies, and writes the rules for the specified package, adding
+// additional dependency rules as needed.
+func ReconcileRules(pkgPath string, rules []*bzl.Rule, managedAttrs []string, dryRun bool, manageGoRules bool) (bool, error) {
+	_, path := findBuildFile(pkgPath)
+	info, err := os.Stat(path)
+	if err != nil && os.IsNotExist(err) {
+		f := &bzl.File{}
+		writeHeaders(f)
+		if manageGoRules {
+			reconcileLoad(f, rules)
+		}
+		writeRules(f, rules)
+		return writeFile(path, f, false, dryRun)
+	} else if err != nil {
+		return false, err
+	}
+	if info.IsDir() {
+		return false, fmt.Errorf("%q cannot be a directory", path)
+	}
+	b, err := ioutil.ReadFile(path)
+	if err != nil {
+		return false, err
+	}
+	f, err := bzl.Parse(path, b)
+	if err != nil {
+		return false, err
+	}
+	oldRules := make(map[string]*bzl.Rule)
+	for _, r := range f.Rules("") {
+		oldRules[r.Name()] = r
+	}
+	for _, r := range rules {
+		o, ok := oldRules[r.Name()]
+		if !ok {
+			f.Stmt = append(f.Stmt, r.Call)
+			continue
+		}
+		if !RuleIsManaged(o, manageGoRules) {
+			continue
+		}
+		reconcileAttr := func(o, n *bzl.Rule, name string) {
+			if e := n.Attr(name); e != nil {
+				o.SetAttr(name, e)
+			} else {
+				o.DelAttr(name)
+			}
+		}
+		for _, attr := range managedAttrs {
+			reconcileAttr(o, r, attr)
+		}
+		delete(oldRules, r.Name())
+	}
+
+	for _, r := range oldRules {
+		if !RuleIsManaged(r, manageGoRules) {
+			continue
+		}
+		f.DelRules(r.Kind(), r.Name())
+	}
+	if manageGoRules {
+		reconcileLoad(f, f.Rules(""))
+	}
+
+	return writeFile(path, f, true, dryRun)
+}
+
+func reconcileLoad(f *bzl.File, rules []*bzl.Rule) {
+	usedRuleKindsMap := map[string]bool{}
+	for _, r := range rules {
+		// Select only the Go rules we need to import, excluding builtins like filegroup.
+		// TODO: make less fragile
+		switch r.Kind() {
+		case "go_prefix", "go_library", "go_binary", "go_test", "go_proto_library", "cgo_genrule", "cgo_library":
+			usedRuleKindsMap[r.Kind()] = true
+		}
+	}
+
+	usedRuleKindsList := []string{}
+	for k := range usedRuleKindsMap {
+		usedRuleKindsList = append(usedRuleKindsList, k)
+	}
+	sort.Strings(usedRuleKindsList)
+
+	for _, r := range f.Rules("load") {
+		const goRulesLabel = "@io_bazel_rules_go//go:def.bzl"
+		args := bzl.Strings(&bzl.ListExpr{List: r.Call.List})
+		if len(args) == 0 {
+			continue
+		}
+		if args[0] != goRulesLabel {
+			continue
+		}
+		if len(usedRuleKindsList) == 0 {
+			f.DelRules(r.Kind(), r.Name())
+			continue
+		}
+		r.Call.List = asExpr(append(
+			[]string{goRulesLabel}, usedRuleKindsList...,
+		)).(*bzl.ListExpr).List
+		break
+	}
+}
+
+// RuleIsManaged returns whether the provided rule is managed by this tool,
+// based on the tags set on the rule.
+func RuleIsManaged(r *bzl.Rule, manageGoRules bool) bool {
+	var automanaged bool
+	if !manageGoRules && (strings.HasPrefix(r.Kind(), "go_") || strings.HasPrefix(r.Kind(), "cgo_")) {
+		return false
+	}
+	for _, tag := range r.AttrStrings("tags") {
+		if tag == automanagedTag {
+			automanaged = true
+			break
+		}
+	}
+	return automanaged
+}
+
+func writeFile(path string, f *bzl.File, exists, dryRun bool) (bool, error) {
+	var info bzl.RewriteInfo
+	bzl.Rewrite(f, &info)
+	out := bzl.Format(f)
+	if exists {
+		orig, err := ioutil.ReadFile(path)
+		if err != nil {
+			return false, err
+		}
+		if bytes.Compare(orig, out) == 0 {
+			return false, nil
+		}
+		if *printDiff {
+			Diff(orig, out)
+		}
+	}
+	if dryRun {
+		fmt.Fprintf(os.Stderr, "DRY-RUN: wrote %q\n", path)
+		return true, nil
+	}
+	werr := ioutil.WriteFile(path, out, 0644)
+	if werr == nil {
+		fmt.Fprintf(os.Stderr, "wrote %q\n", path)
+	}
+	return werr == nil, werr
+}
+
+func context() *build.Context {
+	return &build.Context{
+		GOARCH:      "amd64",
+		GOOS:        "linux",
+		GOROOT:      build.Default.GOROOT,
+		GOPATH:      build.Default.GOPATH,
+		ReleaseTags: []string{"go1.1", "go1.2", "go1.3", "go1.4", "go1.5", "go1.6", "go1.7", "go1.8"},
+		Compiler:    runtime.Compiler,
+		CgoEnabled:  true,
+	}
+}
+
+func walk(root string, walkFn filepath.WalkFunc) error {
+	return nil
+}

vendor/github.com/kubernetes/repo-infra/kazel/sourcerer.go

@@ -0,0 +1,109 @@
+/*
+Copyright 2017 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package main
+
+import (
+	"fmt"
+	"io/ioutil"
+	"path/filepath"
+
+	bzl "github.com/bazelbuild/buildtools/build"
+)
+
+const (
+	pkgSrcsTarget = "package-srcs"
+	allSrcsTarget = "all-srcs"
+)
+
+// walkSource walks the source tree recursively from pkgPath, adding
+// any BUILD files to v.newRules to be formatted.
+//
+// If AddSourcesRules is enabled in the kazel config, then we additionally add
+// package-sources and recursive all-srcs filegroups rules to every BUILD file.
+//
+// Returns the list of children all-srcs targets that should be added to the
+// all-srcs rule of the enclosing package.
+func (v *Vendorer) walkSource(pkgPath string) ([]string, error) {
+	// clean pkgPath since we access v.newRules directly
+	pkgPath = filepath.Clean(pkgPath)
+	for _, r := range v.skippedPaths {
+		if r.MatchString(pkgPath) {
+			return nil, nil
+		}
+	}
+	files, err := ioutil.ReadDir(pkgPath)
+	if err != nil {
+		return nil, err
+	}
+
+	// Find any children packages we need to include in an all-srcs rule.
+	var children []string
+	for _, f := range files {
+		if f.IsDir() {
+			c, err := v.walkSource(filepath.Join(pkgPath, f.Name()))
+			if err != nil {
+				return nil, err
+			}
+			children = append(children, c...)
+		}
+	}
+
+	// This path is a package either if we've added rules or if a BUILD file already exists.
+	_, hasRules := v.newRules[pkgPath]
+	isPkg := hasRules
+	if !isPkg {
+		isPkg, _ = findBuildFile(pkgPath)
+	}
+
+	if !isPkg {
+		// This directory isn't a package (doesn't contain a BUILD file),
+		// but there might be subdirectories that are packages,
+		// so pass that up to our parent.
+		return children, nil
+	}
+
+	// Enforce formatting the BUILD file, even if we're not adding srcs rules
+	if !hasRules {
+		v.addRules(pkgPath, nil)
+	}
+
+	if !v.cfg.AddSourcesRules {
+		return nil, nil
+	}
+
+	pkgSrcsExpr := &bzl.LiteralExpr{Token: `glob(["**"])`}
+	if pkgPath == "." {
+		pkgSrcsExpr = &bzl.LiteralExpr{Token: `glob(["**"], exclude=["bazel-*/**", ".git/**"])`}
+	}
+
+	v.addRules(pkgPath, []*bzl.Rule{
+		newRule(RuleTypeFileGroup,
+			func(_ ruleType) string { return pkgSrcsTarget },
+			map[string]bzl.Expr{
+				"srcs":       pkgSrcsExpr,
+				"visibility": asExpr([]string{"//visibility:private"}),
+			}),
+		newRule(RuleTypeFileGroup,
+			func(_ ruleType) string { return allSrcsTarget },
+			map[string]bzl.Expr{
+				"srcs": asExpr(append(children, fmt.Sprintf(":%s", pkgSrcsTarget))),
+				// TODO: should this be more restricted?
+				"visibility": asExpr([]string{"//visibility:public"}),
+			}),
+	})
+	return []string{fmt.Sprintf("//%s:%s", pkgPath, allSrcsTarget)}, nil
+}

vendor/github.com/pelletier/go-buffruneio/.gitignore

@@ -1 +0,0 @@
-*.test

vendor/github.com/pelletier/go-buffruneio/.travis.yml

@@ -1,7 +0,0 @@
-language: go
-sudo: false
-go:
-    - 1.3.3
-    - 1.4.3
-    - 1.5.3
-    - tip

vendor/github.com/pelletier/go-buffruneio/README.md

@@ -1,62 +0,0 @@
-# buffruneio
-
-[![Tests Status](https://travis-ci.org/pelletier/go-buffruneio.svg?branch=master)](https://travis-ci.org/pelletier/go-buffruneio)
-[![GoDoc](https://godoc.org/github.com/pelletier/go-buffruneio?status.svg)](https://godoc.org/github.com/pelletier/go-buffruneio)
-
-Buffruneio is a wrapper around bufio to provide buffered runes access with
-unlimited unreads.
-
-```go
-import "github.com/pelletier/go-buffruneio"
-```
-
-## Examples
-
-```go
-import (
-    "fmt"
-    "github.com/pelletier/go-buffruneio"
-    "strings"
-)
-
-reader := buffruneio.NewReader(strings.NewReader("abcd"))
-fmt.Println(reader.ReadRune()) // 'a'
-fmt.Println(reader.ReadRune()) // 'b'
-fmt.Println(reader.ReadRune()) // 'c'
-reader.UnreadRune()
-reader.UnreadRune()
-fmt.Println(reader.ReadRune()) // 'b'
-fmt.Println(reader.ReadRune()) // 'c'
-```
-
-## Documentation
-
-The documentation and additional examples are available at
-[godoc.org](http://godoc.org/github.com/pelletier/go-buffruneio).
-
-## Contribute
-
-Feel free to report bugs and patches using GitHub's pull requests system on
-[pelletier/go-toml](https://github.com/pelletier/go-buffruneio). Any feedback is
-much appreciated!
-
-## LICENSE
-
-Copyright (c) 2016 Thomas Pelletier
-
-Permission is hereby granted, free of charge, to any person obtaining a copy of
-this software and associated documentation files (the "Software"), to deal in
-the Software without restriction, including without limitation the rights to
-use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
-the Software, and to permit persons to whom the Software is furnished to do so,
-subject to the following conditions:
-
-The above copyright notice and this permission notice shall be included in all
-copies or substantial portions of the Software.
-
-THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
-IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
-FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
-COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
-IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
-CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

vendor/github.com/pelletier/go-buffruneio/buffruneio.go

@@ -1,110 +0,0 @@
-// Package buffruneio is a wrapper around bufio to provide buffered runes access with unlimited unreads.
-package buffruneio
-
-import (
-	"bufio"
-	"container/list"
-	"errors"
-	"io"
-)
-
-// Rune to indicate end of file.
-const (
-	EOF = -(iota + 1)
-)
-
-// ErrNoRuneToUnread is returned by UnreadRune() when the read index is already at the beginning of the buffer.
-var ErrNoRuneToUnread = errors.New("no rune to unwind")
-
-// Reader implements runes buffering for an io.Reader object.
-type Reader struct {
-	buffer  *list.List
-	current *list.Element
-	input   *bufio.Reader
-}
-
-// NewReader returns a new Reader.
-func NewReader(rd io.Reader) *Reader {
-	return &Reader{
-		buffer: list.New(),
-		input:  bufio.NewReader(rd),
-	}
-}
-
-func (rd *Reader) feedBuffer() error {
-	r, _, err := rd.input.ReadRune()
-
-	if err != nil {
-		if err != io.EOF {
-			return err
-		}
-		r = EOF
-	}
-
-	rd.buffer.PushBack(r)
-	if rd.current == nil {
-		rd.current = rd.buffer.Back()
-	}
-	return nil
-}
-
-// ReadRune reads the next rune from buffer, or from the underlying reader if needed.
-func (rd *Reader) ReadRune() (rune, error) {
-	if rd.current == rd.buffer.Back() || rd.current == nil {
-		err := rd.feedBuffer()
-		if err != nil {
-			return EOF, err
-		}
-	}
-
-	r := rd.current.Value
-	rd.current = rd.current.Next()
-	return r.(rune), nil
-}
-
-// UnreadRune pushes back the previously read rune in the buffer, extending it if needed.
-func (rd *Reader) UnreadRune() error {
-	if rd.current == rd.buffer.Front() {
-		return ErrNoRuneToUnread
-	}
-	if rd.current == nil {
-		rd.current = rd.buffer.Back()
-	} else {
-		rd.current = rd.current.Prev()
-	}
-	return nil
-}
-
-// Forget removes runes stored before the current stream position index.
-func (rd *Reader) Forget() {
-	if rd.current == nil {
-		rd.current = rd.buffer.Back()
-	}
-	for ; rd.current != rd.buffer.Front(); rd.buffer.Remove(rd.current.Prev()) {
-	}
-}
-
-// Peek returns at most the next n runes, reading from the uderlying source if
-// needed. Does not move the current index. It includes EOF if reached.
-func (rd *Reader) Peek(n int) []rune {
-	res := make([]rune, 0, n)
-	cursor := rd.current
-	for i := 0; i < n; i++ {
-		if cursor == nil {
-			err := rd.feedBuffer()
-			if err != nil {
-				return res
-			}
-			cursor = rd.buffer.Back()
-		}
-		if cursor != nil {
-			r := cursor.Value.(rune)
-			res = append(res, r)
-			if r == EOF {
-				return res
-			}
-			cursor = cursor.Next()
-		}
-	}
-	return res
-}

vendor/github.com/pelletier/go-toml/.travis.yml

@@ -1,18 +1,23 @@
+sudo: false
 language: go
 go:
-  - 1.5.4
-  - 1.6.3
-  - 1.7
+  - 1.7.6
+  - 1.8.3
+  - 1.9
   - tip
 matrix:
   allow_failures:
     - go: tip
   fast_finish: true
 script:
+  - if [ -n "$(go fmt ./...)" ]; then exit 1; fi
   - ./test.sh
+  - ./benchmark.sh $TRAVIS_BRANCH https://github.com/$TRAVIS_REPO_SLUG.git
 before_install:
   - go get github.com/axw/gocov/gocov
   - go get github.com/mattn/goveralls
   - if ! go get code.google.com/p/go.tools/cmd/cover; then go get golang.org/x/tools/cmd/cover; fi
+branches:
+  only: [master]
 after_success:
-  - $HOME/gopath/bin/goveralls -service=travis-ci
+  - $HOME/gopath/bin/goveralls -service=travis-ci -coverprofile=coverage.out -repotoken $COVERALLS_TOKEN

vendor/github.com/pelletier/go-toml/BUILD

@@ -6,19 +6,16 @@ go_library(
         "doc.go",
         "keysparsing.go",
         "lexer.go",
-        "match.go",
+        "marshal.go",
         "parser.go",
         "position.go",
-        "query.go",
-        "querylexer.go",
-        "queryparser.go",
         "token.go",
         "toml.go",
-        "tomltree_conversions.go",
+        "tomltree_create.go",
+        "tomltree_write.go",
     ],
     importpath = "github.com/pelletier/go-toml",
     visibility = ["//visibility:public"],
-    deps = ["//vendor/github.com/pelletier/go-buffruneio:go_default_library"],
 )
 
 filegroup(

vendor/github.com/pelletier/go-toml/LICENSE

@@ -1,6 +1,6 @@
 The MIT License (MIT)
 
-Copyright (c) 2013 - 2016 Thomas Pelletier, Eric Anderton
+Copyright (c) 2013 - 2017 Thomas Pelletier, Eric Anderton
 
 Permission is hereby granted, free of charge, to any person obtaining a copy
 of this software and associated documentation files (the "Software"), to deal
@@ -19,4 +19,3 @@ AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 SOFTWARE.
-

vendor/github.com/pelletier/go-toml/README.md

@@ -6,73 +6,74 @@ This library supports TOML version
 [v0.4.0](https://github.com/toml-lang/toml/blob/master/versions/en/toml-v0.4.0.md)
 
 [![GoDoc](https://godoc.org/github.com/pelletier/go-toml?status.svg)](http://godoc.org/github.com/pelletier/go-toml)
+[![license](https://img.shields.io/github/license/pelletier/go-toml.svg)](https://github.com/pelletier/go-toml/blob/master/LICENSE)
 [![Build Status](https://travis-ci.org/pelletier/go-toml.svg?branch=master)](https://travis-ci.org/pelletier/go-toml)
 [![Coverage Status](https://coveralls.io/repos/github/pelletier/go-toml/badge.svg?branch=master)](https://coveralls.io/github/pelletier/go-toml?branch=master)
+[![Go Report Card](https://goreportcard.com/badge/github.com/pelletier/go-toml)](https://goreportcard.com/report/github.com/pelletier/go-toml)
 
 ## Features
 
 Go-toml provides the following features for using data parsed from TOML documents:
 
 * Load TOML documents from files and string data
-* Easily navigate TOML structure using TomlTree
+* Easily navigate TOML structure using Tree
+* Mashaling and unmarshaling to and from data structures
 * Line & column position data for all parsed elements
-* Query support similar to JSON-Path
+* [Query support similar to JSON-Path](query/)
 * Syntax errors contain line and column numbers
 
-Go-toml is designed to help cover use-cases not covered by reflection-based TOML parsing:
-
-* Semantic evaluation of parsed TOML
-* Informing a user of mistakes in the source document, after it has been parsed
-* Programatic handling of default values on a case-by-case basis
-* Using a TOML document as a flexible data-store
-
 ## Import
 
-    import "github.com/pelletier/go-toml"
-
-## Usage
-
-### Example
-
-Say you have a TOML file that looks like this:
-
-```toml
-[postgres]
-user = "pelletier"
-password = "mypassword"
+```go
+import "github.com/pelletier/go-toml"
 ```
 
-Read the username and password like this:
+## Usage example
+
+Read a TOML document:
 
 ```go
-import (
-    "fmt"
-    "github.com/pelletier/go-toml"
-)
+config, _ := toml.Load(`
+[postgres]
+user = "pelletier"
+password = "mypassword"`)
+// retrieve data directly
+user := config.Get("postgres.user").(string)
 
-config, err := toml.LoadFile("config.toml")
-if err != nil {
-    fmt.Println("Error ", err.Error())
-} else {
-    // retrieve data directly
-    user := config.Get("postgres.user").(string)
-    password := config.Get("postgres.password").(string)
+// or using an intermediate object
+postgresConfig := config.Get("postgres").(*toml.Tree)
+password := postgresConfig.Get("password").(string)
+```
 
-    // or using an intermediate object
-    configTree := config.Get("postgres").(*toml.TomlTree)
-    user = configTree.Get("user").(string)
-    password = configTree.Get("password").(string)
-    fmt.Println("User is ", user, ". Password is ", password)
+Or use Unmarshal:
 
-    // show where elements are in the file
-    fmt.Println("User position: %v", configTree.GetPosition("user"))
-    fmt.Println("Password position: %v", configTree.GetPosition("password"))
+```go
+type Postgres struct {
+    User     string
+    Password string
+}
+type Config struct {
+    Postgres Postgres
+}
 
-    // use a query to gather elements without walking the tree
-    results, _ := config.Query("$..[user,password]")
-    for ii, item := range results.Values() {
-      fmt.Println("Query result %d: %v", ii, item)
-    }
+doc := []byte(`
+[postgres]
+user = "pelletier"
+password = "mypassword"`)
+
+config := Config{}
+toml.Unmarshal(doc, &config)
+fmt.Println("user=", config.Postgres.User)
+```
+
+Or use a query:
+
+```go
+// use a query to gather elements without walking the tree
+q, _ := query.Compile("$..[user,password]")
+results := q.Execute(config)
+for ii, item := range results.Values() {
+    fmt.Println("Query result %d: %v", ii, item)
 }
 ```
 
@@ -94,7 +95,7 @@ Go-toml provides two handy command line tools:
 * `tomljson`: Reads a TOML file and outputs its JSON representation.
 
     ```
-    go install github.com/pelletier/go-toml/cmd/tomjson
+    go install github.com/pelletier/go-toml/cmd/tomljson
     tomljson --help
     ```
 

vendor/github.com/pelletier/go-toml/benchmark.json

@@ -0,0 +1,164 @@
+{
+    "array": {
+        "key1": [
+            1,
+            2,
+            3
+        ],
+        "key2": [
+            "red",
+            "yellow",
+            "green"
+        ],
+        "key3": [
+            [
+                1,
+                2
+            ],
+            [
+                3,
+                4,
+                5
+            ]
+        ],
+        "key4": [
+            [
+                1,
+                2
+            ],
+            [
+                "a",
+                "b",
+                "c"
+            ]
+        ],
+        "key5": [
+            1,
+            2,
+            3
+        ],
+        "key6": [
+            1,
+            2
+        ]
+    },
+    "boolean": {
+        "False": false,
+        "True": true
+    },
+    "datetime": {
+        "key1": "1979-05-27T07:32:00Z",
+        "key2": "1979-05-27T00:32:00-07:00",
+        "key3": "1979-05-27T00:32:00.999999-07:00"
+    },
+    "float": {
+        "both": {
+            "key": 6.626e-34
+        },
+        "exponent": {
+            "key1": 5e+22,
+            "key2": 1000000,
+            "key3": -0.02
+        },
+        "fractional": {
+            "key1": 1,
+            "key2": 3.1415,
+            "key3": -0.01
+        },
+        "underscores": {
+            "key1": 9224617.445991227,
+            "key2": 1e+100
+        }
+    },
+    "fruit": [{
+            "name": "apple",
+            "physical": {
+                "color": "red",
+                "shape": "round"
+            },
+            "variety": [{
+                    "name": "red delicious"
+                },
+                {
+                    "name": "granny smith"
+                }
+            ]
+        },
+        {
+            "name": "banana",
+            "variety": [{
+                "name": "plantain"
+            }]
+        }
+    ],
+    "integer": {
+        "key1": 99,
+        "key2": 42,
+        "key3": 0,
+        "key4": -17,
+        "underscores": {
+            "key1": 1000,
+            "key2": 5349221,
+            "key3": 12345
+        }
+    },
+    "products": [{
+            "name": "Hammer",
+            "sku": 738594937
+        },
+        {},
+        {
+            "color": "gray",
+            "name": "Nail",
+            "sku": 284758393
+        }
+    ],
+    "string": {
+        "basic": {
+            "basic": "I'm a string. \"You can quote me\". Name\tJosé\nLocation\tSF."
+        },
+        "literal": {
+            "multiline": {
+                "lines": "The first newline is\ntrimmed in raw strings.\n   All other whitespace\n   is preserved.\n",
+                "regex2": "I [dw]on't need \\d{2} apples"
+            },
+            "quoted": "Tom \"Dubs\" Preston-Werner",
+            "regex": "\u003c\\i\\c*\\s*\u003e",
+            "winpath": "C:\\Users\\nodejs\\templates",
+            "winpath2": "\\\\ServerX\\admin$\\system32\\"
+        },
+        "multiline": {
+            "continued": {
+                "key1": "The quick brown fox jumps over the lazy dog.",
+                "key2": "The quick brown fox jumps over the lazy dog.",
+                "key3": "The quick brown fox jumps over the lazy dog."
+            },
+            "key1": "One\nTwo",
+            "key2": "One\nTwo",
+            "key3": "One\nTwo"
+        }
+    },
+    "table": {
+        "inline": {
+            "name": {
+                "first": "Tom",
+                "last": "Preston-Werner"
+            },
+            "point": {
+                "x": 1,
+                "y": 2
+            }
+        },
+        "key": "value",
+        "subtable": {
+            "key": "another value"
+        }
+    },
+    "x": {
+        "y": {
+            "z": {
+                "w": {}
+            }
+        }
+    }
+}

vendor/github.com/pelletier/go-toml/benchmark.sh

@@ -0,0 +1,32 @@
+#!/bin/bash
+
+set -e
+
+reference_ref=${1:-master}
+reference_git=${2:-.}
+
+if ! `hash benchstat 2>/dev/null`; then
+    echo "Installing benchstat"
+    go get golang.org/x/perf/cmd/benchstat
+    go install golang.org/x/perf/cmd/benchstat
+fi
+
+tempdir=`mktemp -d /tmp/go-toml-benchmark-XXXXXX`
+ref_tempdir="${tempdir}/ref"
+ref_benchmark="${ref_tempdir}/benchmark-`echo -n ${reference_ref}|tr -s '/' '-'`.txt"
+local_benchmark="`pwd`/benchmark-local.txt"
+
+echo "=== ${reference_ref} (${ref_tempdir})"
+git clone ${reference_git} ${ref_tempdir} >/dev/null 2>/dev/null
+pushd ${ref_tempdir} >/dev/null
+git checkout ${reference_ref} >/dev/null 2>/dev/null
+go test -bench=. -benchmem | tee ${ref_benchmark}
+popd >/dev/null
+
+echo ""
+echo "=== local"
+go test -bench=. -benchmem  | tee ${local_benchmark}
+
+echo ""
+echo "=== diff"
+benchstat -delta-test=none ${ref_benchmark} ${local_benchmark}

vendor/github.com/pelletier/go-toml/benchmark.toml

@@ -0,0 +1,244 @@
+################################################################################
+## Comment
+
+# Speak your mind with the hash symbol. They go from the symbol to the end of
+# the line.
+
+
+################################################################################
+## Table
+
+# Tables (also known as hash tables or dictionaries) are collections of
+# key/value pairs. They appear in square brackets on a line by themselves.
+
+[table]
+
+key = "value" # Yeah, you can do this.
+
+# Nested tables are denoted by table names with dots in them. Name your tables
+# whatever crap you please, just don't use #, ., [ or ].
+
+[table.subtable]
+
+key = "another value"
+
+# You don't need to specify all the super-tables if you don't want to. TOML
+# knows how to do it for you.
+
+# [x] you
+# [x.y] don't
+# [x.y.z] need these
+[x.y.z.w] # for this to work
+
+
+################################################################################
+## Inline Table
+
+# Inline tables provide a more compact syntax for expressing tables. They are
+# especially useful for grouped data that can otherwise quickly become verbose.
+# Inline tables are enclosed in curly braces `{` and `}`. No newlines are
+# allowed between the curly braces unless they are valid within a value.
+
+[table.inline]
+
+name = { first = "Tom", last = "Preston-Werner" }
+point = { x = 1, y = 2 }
+
+
+################################################################################
+## String
+
+# There are four ways to express strings: basic, multi-line basic, literal, and
+# multi-line literal. All strings must contain only valid UTF-8 characters.
+
+[string.basic]
+
+basic = "I'm a string. \"You can quote me\". Name\tJos\u00E9\nLocation\tSF."
+
+[string.multiline]
+
+# The following strings are byte-for-byte equivalent:
+key1 = "One\nTwo"
+key2 = """One\nTwo"""
+key3 = """
+One
+Two"""
+
+[string.multiline.continued]
+
+# The following strings are byte-for-byte equivalent:
+key1 = "The quick brown fox jumps over the lazy dog."
+
+key2 = """
+The quick brown \
+
+
+  fox jumps over \
+    the lazy dog."""
+
+key3 = """\
+       The quick brown \
+       fox jumps over \
+       the lazy dog.\
+       """
+
+[string.literal]
+
+# What you see is what you get.
+winpath  = 'C:\Users\nodejs\templates'
+winpath2 = '\\ServerX\admin$\system32\'
+quoted   = 'Tom "Dubs" Preston-Werner'
+regex    = '<\i\c*\s*>'
+
+
+[string.literal.multiline]
+
+regex2 = '''I [dw]on't need \d{2} apples'''
+lines  = '''
+The first newline is
+trimmed in raw strings.
+   All other whitespace
+   is preserved.
+'''
+
+
+################################################################################
+## Integer
+
+# Integers are whole numbers. Positive numbers may be prefixed with a plus sign.
+# Negative numbers are prefixed with a minus sign.
+
+[integer]
+
+key1 = +99
+key2 = 42
+key3 = 0
+key4 = -17
+
+[integer.underscores]
+
+# For large numbers, you may use underscores to enhance readability. Each
+# underscore must be surrounded by at least one digit.
+key1 = 1_000
+key2 = 5_349_221
+key3 = 1_2_3_4_5     # valid but inadvisable
+
+
+################################################################################
+## Float
+
+# A float consists of an integer part (which may be prefixed with a plus or
+# minus sign) followed by a fractional part and/or an exponent part.
+
+[float.fractional]
+
+key1 = +1.0
+key2 = 3.1415
+key3 = -0.01
+
+[float.exponent]
+
+key1 = 5e+22
+key2 = 1e6
+key3 = -2E-2
+
+[float.both]
+
+key = 6.626e-34
+
+[float.underscores]
+
+key1 = 9_224_617.445_991_228_313
+key2 = 1e1_00
+
+
+################################################################################
+## Boolean
+
+# Booleans are just the tokens you're used to. Always lowercase.
+
+[boolean]
+
+True = true
+False = false
+
+
+################################################################################
+## Datetime
+
+# Datetimes are RFC 3339 dates.
+
+[datetime]
+
+key1 = 1979-05-27T07:32:00Z
+key2 = 1979-05-27T00:32:00-07:00
+key3 = 1979-05-27T00:32:00.999999-07:00
+
+
+################################################################################
+## Array
+
+# Arrays are square brackets with other primitives inside. Whitespace is
+# ignored. Elements are separated by commas. Data types may not be mixed.
+
+[array]
+
+key1 = [ 1, 2, 3 ]
+key2 = [ "red", "yellow", "green" ]
+key3 = [ [ 1, 2 ], [3, 4, 5] ]
+#key4 = [ [ 1, 2 ], ["a", "b", "c"] ] # this is ok
+
+# Arrays can also be multiline. So in addition to ignoring whitespace, arrays
+# also ignore newlines between the brackets.  Terminating commas are ok before
+# the closing bracket.
+
+key5 = [
+  1, 2, 3
+]
+key6 = [
+  1,
+  2, # this is ok
+]
+
+
+################################################################################
+## Array of Tables
+
+# These can be expressed by using a table name in double brackets. Each table
+# with the same double bracketed name will be an element in the array. The
+# tables are inserted in the order encountered.
+
+[[products]]
+
+name = "Hammer"
+sku = 738594937
+
+[[products]]
+
+[[products]]
+
+name = "Nail"
+sku = 284758393
+color = "gray"
+
+
+# You can create nested arrays of tables as well.
+
+[[fruit]]
+  name = "apple"
+
+  [fruit.physical]
+    color = "red"
+    shape = "round"
+
+  [[fruit.variety]]
+    name = "red delicious"
+
+  [[fruit.variety]]
+    name = "granny smith"
+
+[[fruit]]
+  name = "banana"
+
+  [[fruit.variety]]
+    name = "plantain"

vendor/github.com/pelletier/go-toml/benchmark.yml

@@ -0,0 +1,121 @@
+---
+array:
+  key1:
+  - 1
+  - 2
+  - 3
+  key2:
+  - red
+  - yellow
+  - green
+  key3:
+  - - 1
+    - 2
+  - - 3
+    - 4
+    - 5
+  key4:
+  - - 1
+    - 2
+  - - a
+    - b
+    - c
+  key5:
+  - 1
+  - 2
+  - 3
+  key6:
+  - 1
+  - 2
+boolean:
+  'False': false
+  'True': true
+datetime:
+  key1: '1979-05-27T07:32:00Z'
+  key2: '1979-05-27T00:32:00-07:00'
+  key3: '1979-05-27T00:32:00.999999-07:00'
+float:
+  both:
+    key: 6.626e-34
+  exponent:
+    key1: 5.0e+22
+    key2: 1000000
+    key3: -0.02
+  fractional:
+    key1: 1
+    key2: 3.1415
+    key3: -0.01
+  underscores:
+    key1: 9224617.445991227
+    key2: 1.0e+100
+fruit:
+- name: apple
+  physical:
+    color: red
+    shape: round
+  variety:
+  - name: red delicious
+  - name: granny smith
+- name: banana
+  variety:
+  - name: plantain
+integer:
+  key1: 99
+  key2: 42
+  key3: 0
+  key4: -17
+  underscores:
+    key1: 1000
+    key2: 5349221
+    key3: 12345
+products:
+- name: Hammer
+  sku: 738594937
+- {}
+- color: gray
+  name: Nail
+  sku: 284758393
+string:
+  basic:
+    basic: "I'm a string. \"You can quote me\". Name\tJosé\nLocation\tSF."
+  literal:
+    multiline:
+      lines: |
+        The first newline is
+        trimmed in raw strings.
+           All other whitespace
+           is preserved.
+      regex2: I [dw]on't need \d{2} apples
+    quoted: Tom "Dubs" Preston-Werner
+    regex: "<\\i\\c*\\s*>"
+    winpath: C:\Users\nodejs\templates
+    winpath2: "\\\\ServerX\\admin$\\system32\\"
+  multiline:
+    continued:
+      key1: The quick brown fox jumps over the lazy dog.
+      key2: The quick brown fox jumps over the lazy dog.
+      key3: The quick brown fox jumps over the lazy dog.
+    key1: |-
+      One
+      Two
+    key2: |-
+      One
+      Two
+    key3: |-
+      One
+      Two
+table:
+  inline:
+    name:
+      first: Tom
+      last: Preston-Werner
+    point:
+      x: 1
+      y: 2
+  key: value
+  subtable:
+    key: another value
+x:
+  y:
+    z:
+      w: {}

vendor/github.com/pelletier/go-toml/clean.sh

@@ -1,6 +0,0 @@
-#!/bin/bash
-# fail out of the script if anything here fails
-set -e
-
-# clear out stuff generated by test.sh
-rm -rf src test_program_bin toml-test