fix bug with migrating annotations

kyaml/kio/kioutil/kioutil.go

@@ -55,6 +55,10 @@ func GetFileAnnotations(rn *yaml.RNode) (string, string, error) {
 func CopyLegacyAnnotations(rn *yaml.RNode) error {
 	meta, err := rn.GetMeta()
 	if err != nil {
+		if err == yaml.ErrMissingMetadata {
+			// resource has no metadata, this should be a no-op
+			return nil
+		}
 		return err
 	}
 	if err := copyAnnotations(meta, rn, LegacyPathAnnotation, PathAnnotation); err != nil {
@@ -71,12 +75,14 @@ func CopyLegacyAnnotations(rn *yaml.RNode) error {
 
 func copyAnnotations(meta yaml.ResourceMeta, rn *yaml.RNode, legacyKey string, newKey string) error {
 	newValue := meta.Annotations[newKey]
+	legacyValue := meta.Annotations[legacyKey]
 	if newValue != "" {
-		if err := rn.PipeE(yaml.SetAnnotation(legacyKey, newValue)); err != nil {
-			return err
+		if legacyValue == "" {
+			if err := rn.PipeE(yaml.SetAnnotation(legacyKey, newValue)); err != nil {
+				return err
+			}
 		}
 	} else {
-		legacyValue := meta.Annotations[legacyKey]
 		if legacyValue != "" {
 			if err := rn.PipeE(yaml.SetAnnotation(newKey, legacyValue)); err != nil {
 				return err

kyaml/kio/kioutil/kioutil_test.go

@@ -374,3 +374,80 @@ func TestCreatePathAnnotationValue(t *testing.T) {
 		}
 	}
 }
+
+func TestCopyLegacyAnnotations(t *testing.T) {
+	var tests = []struct {
+		input    string
+		expected string
+	}{
+		{
+			input: `apiVersion: v1
+kind: Foo
+metadata:
+  name: foobar
+  annotations:
+    config.kubernetes.io/path: 'a/b.yaml'
+    config.kubernetes.io/index: '5'
+`,
+			expected: `apiVersion: v1
+kind: Foo
+metadata:
+  name: foobar
+  annotations:
+    config.kubernetes.io/path: 'a/b.yaml'
+    config.kubernetes.io/index: '5'
+    internal.config.kubernetes.io/path: 'a/b.yaml'
+    internal.config.kubernetes.io/index: '5'
+`,
+		},
+		{
+			input: `apiVersion: v1
+kind: Foo
+metadata:
+  name: foobar
+  annotations:
+    internal.config.kubernetes.io/path: 'a/b.yaml'
+    internal.config.kubernetes.io/index: '5'
+`,
+			expected: `apiVersion: v1
+kind: Foo
+metadata:
+  name: foobar
+  annotations:
+    internal.config.kubernetes.io/path: 'a/b.yaml'
+    internal.config.kubernetes.io/index: '5'
+    config.kubernetes.io/path: 'a/b.yaml'
+    config.kubernetes.io/index: '5'
+`,
+		},
+		{
+			input: `apiVersion: v1
+kind: Foo
+metadata:
+ name: foobar
+ annotations:
+   internal.config.kubernetes.io/path: 'a/b.yaml'
+   config.kubernetes.io/path: 'c/d.yaml'
+`,
+			expected: `apiVersion: v1
+kind: Foo
+metadata:
+  name: foobar
+  annotations:
+    internal.config.kubernetes.io/path: 'a/b.yaml'
+    config.kubernetes.io/path: 'c/d.yaml'
+`,
+		},
+	}
+
+	for _, tc := range tests {
+		rw := kio.ByteReadWriter{
+			Reader:                bytes.NewBufferString(tc.input),
+			OmitReaderAnnotations: true,
+		}
+		nodes, err := rw.Read()
+		assert.NoError(t, err)
+		assert.NoError(t, kioutil.CopyLegacyAnnotations(nodes[0]))
+		assert.Equal(t, tc.expected, nodes[0].MustString())
+	}
+}