From c469e80cad74b417e0d5aa946a98d2e0315b5cc6 Mon Sep 17 00:00:00 2001
From: jregan <jregan@google.com>
Date: Sun, 9 Aug 2020 12:36:15 -0700
Subject: [PATCH] Add RNode.IsNilOrEmpty and test.

---
 kyaml/yaml/types.go      |  9 +++++++++
 kyaml/yaml/types_test.go | 32 ++++++++++++++++++++++++++++++++
 2 files changed, 41 insertions(+)

diff --git a/kyaml/yaml/types.go b/kyaml/yaml/types.go
index 6750c5be3..cdaa6ecdb 100644
--- a/kyaml/yaml/types.go
+++ b/kyaml/yaml/types.go
@@ -383,6 +383,15 @@ func (rn *RNode) IsTaggedNull() bool {
 	return !rn.IsNil() && IsYNodeTaggedNull(rn.YNode())
 }
 
+// IsNilOrEmpty is true if the node is nil,
+// has no YNode, or has YNode that appears empty.
+func (rn *RNode) IsNilOrEmpty() bool {
+	return rn.IsNil() ||
+		IsYNodeTaggedNull(rn.YNode()) ||
+		IsYNodeEmptyMap(rn.YNode()) ||
+		IsYNodeEmptySeq(rn.YNode())
+}
+
 // GetMeta returns the ResourceMeta for an RNode
 func (rn *RNode) GetMeta() (ResourceMeta, error) {
 	if IsMissingOrNull(rn) {
diff --git a/kyaml/yaml/types_test.go b/kyaml/yaml/types_test.go
index 0e4447ddf..2b3da83a3 100644
--- a/kyaml/yaml/types_test.go
+++ b/kyaml/yaml/types_test.go
@@ -323,3 +323,35 @@ func TestIsTaggedNull(t *testing.T) {
 		t.Fatalf("empty list should not be tagged null")
 	}
 }
+
+func TestRNodeIsNilOrEmpty(t *testing.T) {
+	var rn *RNode
+
+	if !rn.IsNilOrEmpty() {
+		t.Fatalf("uninitialized RNode should be empty")
+	}
+
+	if !NewRNode(nil).IsNilOrEmpty() {
+		t.Fatalf("missing value YNode should be empty")
+	}
+
+	if !MakeNullNode().IsNilOrEmpty() {
+		t.Fatalf("value tagged null should be empty")
+	}
+
+	if !NewMapRNode(nil).IsNilOrEmpty() {
+		t.Fatalf("empty map should be empty")
+	}
+
+	if NewMapRNode(&map[string]string{"foo": "bar"}).IsNilOrEmpty() {
+		t.Fatalf("non-empty map should not be empty")
+	}
+
+	if !NewListRNode().IsNilOrEmpty() {
+		t.Fatalf("empty list should be empty")
+	}
+
+	if NewListRNode("foo").IsNilOrEmpty() {
+		t.Fatalf("non-empty list should not be empty")
+	}
+}