feat: write initial doc separator when annotation present

Author: grothej

kyaml/kio/byteio_reader.go

@@ -356,7 +356,6 @@ func (r *ByteReader) setResourceAnnotations(n *yaml.RNode, index int, originalYA
 			r.SetAnnotations[kioutil.SeqIndentAnnotation] = seqIndentStyle
 		}
 	}
-	//
 	if index == 0 && r.PreserveInitialDocSep &&
 		strings.HasPrefix(originalYAML, "---") {
 		r.SetAnnotations[kioutil.InitialDocSepAnnotation] = "true"

kyaml/kio/byteio_writer.go

@@ -63,6 +63,14 @@ func (w ByteWriter) Write(inputNodes []*yaml.RNode) error {
 	// Even though we use the this value further down we must check this before removing annotations
 	jsonEncodeSingleBareNode := w.shouldJSONEncodeSingleBareNode(nodes)
 
+	// Check for InitialDocSepAnnotation on a node
+	var retainInitialDocSep bool
+	for i := range nodes {
+		if len(nodes[i].GetAnnotations(kioutil.InitialDocSepAnnotation)) > 0 {
+			retainInitialDocSep = true
+			break
+		}
+	}
 	// store seqindent annotation value for each node in order to set the encoder indentation
 	var seqIndentsForNodes []string
 	for i := range nodes {
@@ -85,6 +93,11 @@ func (w ByteWriter) Write(inputNodes []*yaml.RNode) error {
 			if err != nil {
 				return errors.Wrap(err)
 			}
+
+			_, err = nodes[i].Pipe(yaml.ClearAnnotation(kioutil.InitialDocSepAnnotation))
+			if err != nil {
+				return errors.Wrap(err)
+			}
 		}
 		for _, a := range w.ClearAnnotations {
 			_, err := nodes[i].Pipe(yaml.ClearAnnotation(a))
@@ -108,7 +121,13 @@ func (w ByteWriter) Write(inputNodes []*yaml.RNode) error {
 		return errors.Wrap(encoder.Encode(nodes[0]))
 	}
 
+	if retainInitialDocSep {
+		if _, err := w.Writer.Write([]byte("---\n")); err != nil {
+			return errors.Wrap(err)
+		}
+	}
 	encoder := yaml.NewEncoder(w.Writer)
+
 	defer encoder.Close()
 	// don't wrap the elements
 	if w.WrappingKind == "" {

kyaml/kio/byteio_writer_test.go

@@ -380,6 +380,71 @@ metadata:
 `,
 		},
 
+		//
+		// Test Case
+		//
+		{
+			name:     "add_initial_doc_sep",
+			instance: ByteWriter{KeepReaderAnnotations: true},
+			items: []string{
+				`a: b
+metadata:
+  annotations:
+    internal.config.kubernetes.io/index: 0
+    internal.config.kubernetes.io/path: "a/b/a_test.yaml"
+    internal.config.kubernetes.io/initial-doc-sep: "true"
+`,
+			},
+
+			expectedOutput: `---
+a: b
+metadata:
+  annotations:
+    internal.config.kubernetes.io/index: 0
+    internal.config.kubernetes.io/path: "a/b/a_test.yaml"
+    internal.config.kubernetes.io/initial-doc-sep: "true"
+`,
+		},
+		//
+		// Test Case
+		//
+		{
+			name:     "multiple_nodes_with_initial_doc_sep_annotations",
+			instance: ByteWriter{KeepReaderAnnotations: true},
+			items: []string{
+				`a: b
+metadata:
+  annotations:
+    internal.config.kubernetes.io/index: 0
+    internal.config.kubernetes.io/path: "a/b/a_test.yaml"
+    internal.config.kubernetes.io/initial-doc-sep: "true"
+`,
+				`c: d
+metadata:
+  annotations:
+    internal.config.kubernetes.io/index: 0
+    internal.config.kubernetes.io/path: "a/b/b_test.yaml"
+    internal.config.kubernetes.io/inital-doc-sep: "true"
+`,
+			},
+
+			expectedOutput: `---
+a: b
+metadata:
+  annotations:
+    internal.config.kubernetes.io/index: 0
+    internal.config.kubernetes.io/path: "a/b/a_test.yaml"
+    internal.config.kubernetes.io/initial-doc-sep: "true"
+---
+c: d
+metadata:
+  annotations:
+    internal.config.kubernetes.io/index: 0
+    internal.config.kubernetes.io/path: "a/b/b_test.yaml"
+    internal.config.kubernetes.io/initial-doc-sep: "true"
+`,
+		},
+
 		//
 		// Test Case
 		//