Replace apimachinery diff.StringDiff with cmp

I forced failures of most of these tests and verified readability

pkg/api/testing/copy_test.go

@@ -23,13 +23,12 @@ import (
 	"testing"
 
 	"github.com/google/go-cmp/cmp"
-	"github.com/google/gofuzz"
+	fuzz "github.com/google/gofuzz"
 
 	"k8s.io/apimachinery/pkg/api/apitesting/fuzzer"
 	"k8s.io/apimachinery/pkg/api/apitesting/roundtrip"
 	"k8s.io/apimachinery/pkg/runtime"
 	"k8s.io/apimachinery/pkg/runtime/schema"
-	"k8s.io/apimachinery/pkg/util/diff"
 	"k8s.io/kubernetes/pkg/api/legacyscheme"
 )
 
@@ -71,7 +70,7 @@ func doDeepCopyTest(t *testing.T, kind schema.GroupVersionKind, f *fuzz.Fuzzer)
 	}
 
 	if !bytes.Equal(prefuzzData.Bytes(), postfuzzData.Bytes()) {
-		t.Log(diff.StringDiff(prefuzzData.String(), postfuzzData.String()))
+		t.Log(cmp.Diff(prefuzzData.String(), postfuzzData.String()))
 		t.Errorf("Fuzzing copy modified original of %#v", kind)
 		return
 	}

plugin/pkg/auth/authorizer/rbac/bootstrappolicy/policy_test.go

@@ -22,13 +22,13 @@ import (
 	"reflect"
 	"testing"
 
+	"github.com/google/go-cmp/cmp"
 	"sigs.k8s.io/yaml"
 
 	v1 "k8s.io/api/core/v1"
 	rbacv1 "k8s.io/api/rbac/v1"
 	"k8s.io/apimachinery/pkg/api/meta"
 	"k8s.io/apimachinery/pkg/runtime"
-	"k8s.io/apimachinery/pkg/util/diff"
 	"k8s.io/apimachinery/pkg/util/sets"
 	"k8s.io/component-helpers/auth/rbac/validation"
 	"k8s.io/kubernetes/pkg/api/legacyscheme"
@@ -253,7 +253,7 @@ func testObjects(t *testing.T, list *api.List, fixtureFilename string) {
 				t.Logf("Could not update data in %s: %v", filename, err)
 			}
 		} else {
-			t.Logf("Diff between bootstrap data and fixture data in %s:\n-------------\n%s", filename, diff.StringDiff(string(yamlData), string(expectedYAML)))
+			t.Logf("Diff between bootstrap data and fixture data in %s:\n-------------\n%s", filename, cmp.Diff(string(yamlData), string(expectedYAML)))
 			t.Logf("If the change is expected, re-run with %s=true to update the fixtures", updateEnvVar)
 		}
 	}

staging/src/k8s.io/apiextensions-apiserver/pkg/controller/openapi/builder/builder_test.go

@@ -21,13 +21,13 @@ import (
 	"strings"
 	"testing"
 
+	"github.com/google/go-cmp/cmp"
 	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
 
 	apiextensionsinternal "k8s.io/apiextensions-apiserver/pkg/apis/apiextensions"
 	apiextensionsv1 "k8s.io/apiextensions-apiserver/pkg/apis/apiextensions/v1"
 	structuralschema "k8s.io/apiextensions-apiserver/pkg/apiserver/schema"
-	"k8s.io/apimachinery/pkg/util/diff"
 	"k8s.io/apimachinery/pkg/util/json"
 	"k8s.io/apimachinery/pkg/util/sets"
 	"k8s.io/apiserver/pkg/endpoints"
@@ -438,7 +438,7 @@ func TestNewBuilder(t *testing.T) {
 
 			gotListSchema := got.listSchema.Properties["items"].Items.Schema
 			if !reflect.DeepEqual(&wantedItemsSchema, gotListSchema) {
-				t.Errorf("unexpected list schema: %s (want/got)", schemaDiff(&wantedItemsSchema, gotListSchema))
+				t.Errorf("unexpected list schema:\n%s", schemaDiff(&wantedItemsSchema, gotListSchema))
 			}
 		})
 	}
@@ -560,15 +560,8 @@ func properties(p map[string]spec.Schema) sets.String {
 }
 
 func schemaDiff(a, b *spec.Schema) string {
-	as, err := json.Marshal(a)
+	// This option construct allows diffing all fields, even unexported ones.
-	if err != nil {
+	return cmp.Diff(a, b, cmp.Exporter(func(reflect.Type) bool { return true }))
-		panic(err)
-	}
-	bs, err := json.Marshal(b)
-	if err != nil {
-		panic(err)
-	}
-	return diff.StringDiff(string(as), string(bs))
 }
 
 func TestBuildOpenAPIV2(t *testing.T) {

staging/src/k8s.io/apimachinery/pkg/util/diff/diff.go

@@ -27,30 +27,16 @@ import (
 	"k8s.io/apimachinery/pkg/util/dump"
 )
 
-// StringDiff diffs a and b and returns a human readable diff.
-func StringDiff(a, b string) string {
-	ba := []byte(a)
-	bb := []byte(b)
-	out := []byte{}
-	i := 0
-	for ; i < len(ba) && i < len(bb); i++ {
-		if ba[i] != bb[i] {
-			break
-		}
-		out = append(out, ba[i])
-	}
-	out = append(out, []byte("\n\nA: ")...)
-	out = append(out, ba[i:]...)
-	out = append(out, []byte("\n\nB: ")...)
-	out = append(out, bb[i:]...)
-	out = append(out, []byte("\n\n")...)
-	return string(out)
-}
-
 func legacyDiff(a, b interface{}) string {
 	return cmp.Diff(a, b)
 }
 
+// StringDiff diffs a and b and returns a human readable diff.
+// DEPRECATED: use github.com/google/go-cmp/cmp.Diff
+func StringDiff(a, b string) string {
+	return legacyDiff(a, b)
+}
+
 // ObjectDiff prints the diff of two go objects and fails if the objects
 // contain unhandled unexported fields.
 // DEPRECATED: use github.com/google/go-cmp/cmp.Diff

staging/src/k8s.io/apimachinery/pkg/util/diff/diff_test.go

@@ -1,29 +0,0 @@
-/*
-Copyright 2016 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 diff
-
-import (
-	"testing"
-)
-
-func TestStringDiff(t *testing.T) {
-	diff := StringDiff("aaabb", "aaacc")
-	expect := "aaa\n\nA: bb\n\nB: cc\n\n"
-	if diff != expect {
-		t.Errorf("diff returned %v", diff)
-	}
-}

staging/src/k8s.io/apiserver/pkg/endpoints/apiserver_test.go

@@ -2061,12 +2061,6 @@ func TestWatchTable(t *testing.T) {
 				actual = append(actual, &event)
 			}
 			if !reflect.DeepEqual(test.expected, actual) {
-				for i := range test.expected {
-					if i >= len(actual) {
-						break
-					}
-					t.Logf("%s", diff.StringDiff(string(test.expected[i].Object.Raw), string(actual[i].Object.Raw)))
-				}
 				t.Fatalf("unexpected: %s", diff.ObjectReflectDiff(test.expected, actual))
 			}
 		})

staging/src/k8s.io/kubectl/pkg/cmd/edit/edit_test.go

@@ -27,12 +27,12 @@ import (
 	"strings"
 	"testing"
 
+	"github.com/google/go-cmp/cmp"
 	"github.com/spf13/cobra"
 
 	yaml "gopkg.in/yaml.v2"
 
 	"k8s.io/apimachinery/pkg/runtime/schema"
-	"k8s.io/apimachinery/pkg/util/diff"
 	"k8s.io/apimachinery/pkg/util/sets"
 	"k8s.io/cli-runtime/pkg/genericiooptions"
 	"k8s.io/cli-runtime/pkg/resource"
@@ -124,7 +124,7 @@ func TestEdit(t *testing.T) {
 					// Convenience to allow recapturing the input and persisting it here
 					os.WriteFile(inputFile, body, os.FileMode(0644))
 				} else {
-					t.Errorf("%s, step %d: diff in edit content:\n%s", name, i, diff.StringDiff(string(body), string(expectedInput)))
+					t.Errorf("%s, step %d: diff in edit content:\n%s", name, i, cmp.Diff(string(body), string(expectedInput)))
 					t.Logf("If the change in input is expected, rerun tests with %s=true to update input fixtures", updateEnvVar)
 				}
 			}
@@ -147,7 +147,7 @@ func TestEdit(t *testing.T) {
 				// Convenience to allow recapturing the input and persisting it here
 				os.WriteFile(inputFile, body, os.FileMode(0644))
 			} else {
-				t.Errorf("%s, step %d: diff in edit content:\n%s", name, i, diff.StringDiff(string(body), string(expectedInput)))
+				t.Errorf("%s, step %d: diff in edit content:\n%s", name, i, cmp.Diff(string(body), string(expectedInput)))
 				t.Logf("If the change in input is expected, rerun tests with %s=true to update input fixtures", updateEnvVar)
 			}
 		}

staging/src/k8s.io/kubectl/pkg/cmd/get/get_test.go

@@ -26,6 +26,7 @@ import (
 	"strings"
 	"testing"
 
+	"github.com/google/go-cmp/cmp"
 	appsv1 "k8s.io/api/apps/v1"
 	autoscalingv1 "k8s.io/api/autoscaling/v1"
 	batchv1 "k8s.io/api/batch/v1"
@@ -36,7 +37,6 @@ import (
 	metav1beta1 "k8s.io/apimachinery/pkg/apis/meta/v1beta1"
 	"k8s.io/apimachinery/pkg/runtime"
 	"k8s.io/apimachinery/pkg/runtime/serializer/streaming"
-	"k8s.io/apimachinery/pkg/util/diff"
 	"k8s.io/apimachinery/pkg/watch"
 	"k8s.io/cli-runtime/pkg/genericiooptions"
 	"k8s.io/cli-runtime/pkg/resource"
@@ -1497,7 +1497,7 @@ func TestGetMultipleTypeObjectsAsList(t *testing.T) {
 }
 `
 	if e, a := expected, buf.String(); e != a {
-		t.Errorf("did not match: %v", diff.StringDiff(e, a))
+		t.Errorf("did not match:\n%v", cmp.Diff(e, a))
 	}
 }
 

staging/src/k8s.io/kubectl/pkg/explain/formatter_test.go

@@ -20,7 +20,7 @@ import (
 	"bytes"
 	"testing"
 
-	"k8s.io/apimachinery/pkg/util/diff"
+	"github.com/google/go-cmp/cmp"
 )
 
 func TestFormatterWrite(t *testing.T) {
@@ -113,7 +113,7 @@ fringilla velit.
 `
 
 	if buf.String() != want {
-		t.Errorf("Diff:\n%s", diff.StringDiff(buf.String(), want))
+		t.Errorf("Diff:\n%s", cmp.Diff(buf.String(), want))
 	}
 }
 

staging/src/k8s.io/pod-security-admission/test/fixtures_test.go

@@ -24,9 +24,9 @@ import (
 	"strings"
 	"testing"
 
+	"github.com/google/go-cmp/cmp"
 	corev1 "k8s.io/api/core/v1"
 	"k8s.io/apimachinery/pkg/runtime"
-	"k8s.io/apimachinery/pkg/util/diff"
 	"k8s.io/apimachinery/pkg/util/sets"
 	"k8s.io/client-go/kubernetes/scheme"
 	"k8s.io/pod-security-admission/api"
@@ -167,7 +167,7 @@ func testFixtureFile(t *testing.T, dir, name string, pod *corev1.Pod) string {
 				t.Logf("Could not update data in %s: %v", filename, err)
 			}
 		} else {
-			t.Logf("Diff between generated data and fixture data in %s:\n-------------\n%s", filename, diff.StringDiff(string(yamlData), string(expectedYAML)))
+			t.Logf("Diff between generated data and fixture data in %s:\n-------------\n%s", filename, cmp.Diff(string(yamlData), string(expectedYAML)))
 			t.Logf("If the change is expected, re-run with %s=true to update the fixtures", updateEnvVar)
 		}
 	}