Vendor godep v79 and use it

vendor/github.com/tools/godep/go.go

@@ -0,0 +1,129 @@
+package main
+
+import (
+	"fmt"
+	"log"
+	"os"
+	"os/exec"
+	"path/filepath"
+	"strings"
+)
+
+var cmdGo = &Command{
+	Name:  "go",
+	Args:  "command [arguments]",
+	Short: "run the go tool with saved dependencies",
+	Long: `
+Go runs the go tool with a modified GOPATH giving access to
+dependencies saved in Godeps.
+
+Any go tool command can run this way, but "godep go get"
+is unnecessary and has been disabled. Instead, use
+"godep go install".
+`,
+	Run:          runGo,
+	OnlyInGOPATH: true,
+}
+
+// Find the godep GOPATH for this file tree and run the go tool.
+func runGo(cmd *Command, args []string) {
+	gopath := prepareGopath()
+	if s := os.Getenv("GOPATH"); s != "" {
+		gopath += string(os.PathListSeparator) + os.Getenv("GOPATH")
+	}
+	if len(args) > 0 && args[0] == "get" {
+		log.Printf("invalid subcommand: %q", "go get")
+		fmt.Fprintln(os.Stderr, "Use 'godep go install' instead.")
+		fmt.Fprintln(os.Stderr, "Run 'godep help go' for usage.")
+		os.Exit(2)
+	}
+	c := exec.Command("go", args...)
+	c.Env = append(envNoGopath(), "GOPATH="+gopath)
+	c.Stdin = os.Stdin
+	c.Stdout = os.Stdout
+	c.Stderr = os.Stderr
+	err := c.Run()
+	if err != nil {
+		log.Fatalln("go", err)
+	}
+}
+
+// prepareGopath reads dependency information from the filesystem
+// entry name, fetches any necessary code, and returns a gopath
+// causing the specified dependencies to be used.
+func prepareGopath() (gopath string) {
+	dir, isDir := findGodeps()
+	if dir == "" {
+		log.Fatalln("No Godeps found (or in any parent directory)")
+	}
+	if !isDir {
+		log.Fatalln(strings.TrimSpace(needSource))
+	}
+	return filepath.Join(dir, "Godeps", "_workspace")
+}
+
+// findGodeps looks for a directory entry "Godeps" in the
+// current directory or any parent, and returns the containing
+// directory and whether the entry itself is a directory.
+// If Godeps can't be found, findGodeps returns "".
+// For any other error, it exits the program.
+func findGodeps() (dir string, isDir bool) {
+	wd, err := os.Getwd()
+	if err != nil {
+		log.Fatalln(err)
+	}
+	return findInParents(wd, "Godeps")
+}
+
+// isRoot returns true iff a path is a root.
+// On Unix: "/".
+// On Windows: "C:\", "D:\", ...
+func isRoot(p string) bool {
+	p = filepath.Clean(p)
+	volume := filepath.VolumeName(p)
+
+	p = strings.TrimPrefix(p, volume)
+	p = filepath.ToSlash(p)
+
+	return p == "/"
+}
+
+// findInParents returns the path to the directory containing name
+// in dir or any ancestor, and whether name itself is a directory.
+// If name cannot be found, findInParents returns the empty string.
+func findInParents(dir, name string) (container string, isDir bool) {
+	for {
+		fi, err := os.Stat(filepath.Join(dir, name))
+		if os.IsNotExist(err) && isRoot(dir) {
+			return "", false
+		}
+		if os.IsNotExist(err) {
+			dir = filepath.Dir(dir)
+			continue
+		}
+		if err != nil {
+			log.Fatalln(err)
+		}
+		return dir, fi.IsDir()
+	}
+}
+
+func envNoGopath() (a []string) {
+	for _, s := range os.Environ() {
+		if !strings.HasPrefix(s, "GOPATH=") {
+			a = append(a, s)
+		}
+	}
+	return a
+}
+
+const needSource = `
+outdated Godeps missing source code
+
+This dependency list was created with an old version of godep.
+
+To work around this, you have two options:
+1. Run 'godep restore', and try again.
+2. Ask the maintainer to switch to a newer version of godep,
+then try again with the updated package.
+`