Replace apimachinery diff.StringDiff with cmp

I forced failures of most of these tests and verified readability

Kubernetes-commit: 97bab44cae3857710bfb072d233e654784082ee3

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)
 			}
 		}

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))
 	}
 }
 

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))
 	}
 }