From 01b34c8ea0f8ee9bbe0267f458fc5a134a5acfac Mon Sep 17 00:00:00 2001
From: jregan <jregan@google.com>
Date: Sun, 9 Aug 2020 11:27:25 -0700
Subject: [PATCH] Add tests for IsNil

---
 kyaml/yaml/types.go      | 14 +++++++-------
 kyaml/yaml/types_test.go | 24 ++++++++++++++++++++++++
 2 files changed, 31 insertions(+), 7 deletions(-)

diff --git a/kyaml/yaml/types.go b/kyaml/yaml/types.go
index f44aa65e2..46c4c92d7 100644
--- a/kyaml/yaml/types.go
+++ b/kyaml/yaml/types.go
@@ -36,7 +36,7 @@ func MakeNullNode() *RNode {
 // IsMissingOrNull is true if the RNode is nil or explicitly tagged null.
 // TODO: make this a method on RNode.
 func IsMissingOrNull(node *RNode) bool {
-	return IsNil(node) || node.YNode().Tag == NodeTagNull
+	return node.IsNil() || node.YNode().Tag == NodeTagNull
 }
 
 // Deprecated.  Use IsMissingOrNull instead.
@@ -49,13 +49,8 @@ func IsEmptyMap(node *RNode) bool {
 	return IsMissingOrNull(node) || IsYNodeEmptyMap(node.YNode())
 }
 
-// IsNil return true if the node is nil, or its underlying YNode is nil.
-func IsNil(node *RNode) bool {
-	return node == nil || node.YNode() == nil
-}
-
 func IsNull(node *RNode) bool {
-	return !IsNil(node) && node.YNode().Tag == NodeTagNull
+	return !node.IsNil() && node.YNode().Tag == NodeTagNull
 }
 
 func IsFieldEmpty(node *MapNode) bool {
@@ -377,6 +372,11 @@ const (
 	LabelsField      = "labels"
 )
 
+// IsNil is true if the node is nil, or its underlying YNode is nil.
+func (rn *RNode) IsNil() bool {
+	return rn == nil || rn.YNode() == nil
+}
+
 // 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 53b687e9a..27c60d4b8 100644
--- a/kyaml/yaml/types_test.go
+++ b/kyaml/yaml/types_test.go
@@ -220,3 +220,27 @@ func TestIsEmptyMap(t *testing.T) {
 		t.Fatalf("input: empty map")
 	}
 }
+
+func TestIsNil(t *testing.T) {
+	var rn *RNode
+
+	if !rn.IsNil() {
+		t.Fatalf("uninitialized RNode should be nil")
+	}
+
+	if !NewRNode(nil).IsNil() {
+		t.Fatalf("missing value YNode should be nil")
+	}
+
+	if MakeNullNode().IsNil() {
+		t.Fatalf("value tagged null is not nil")
+	}
+
+	if NewMapRNode(nil).IsNil() {
+		t.Fatalf("empty map not nil")
+	}
+
+	if NewListRNode().IsNil() {
+		t.Fatalf("empty list not nil")
+	}
+}