From 83ff8a2f49f820fb355b24c65b8629710dca8a54 Mon Sep 17 00:00:00 2001
From: Vandit Singh <107131545+Vandit1604@users.noreply.github.com>
Date: Thu, 18 Jan 2024 13:14:19 +0530
Subject: [PATCH] Negative index regression test for json-patch (#122625)

* add testcase with negative index

* exercise successful negative index patching

* use different values for testing

Co-authored-by: Chris Bandy <bandy.chris@gmail.com>

---------

Co-authored-by: Chris Bandy <bandy.chris@gmail.com>
---
 .../pkg/endpoints/handlers/rest_test.go       |  5 +++++
 .../kubectl/pkg/cmd/util/helpers_test.go      | 20 +++++++++++++++++++
 2 files changed, 25 insertions(+)

diff --git a/staging/src/k8s.io/apiserver/pkg/endpoints/handlers/rest_test.go b/staging/src/k8s.io/apiserver/pkg/endpoints/handlers/rest_test.go
index 465986319a3..54931785da1 100644
--- a/staging/src/k8s.io/apiserver/pkg/endpoints/handlers/rest_test.go
+++ b/staging/src/k8s.io/apiserver/pkg/endpoints/handlers/rest_test.go
@@ -244,6 +244,10 @@ func TestJSONPatch(t *testing.T) {
 			expectedError:     "the server rejected our request due to an error in our request",
 			expectedErrorType: metav1.StatusReasonInvalid,
 		},
+		{
+			name:  "valid-negative-index-patch",
+			patch: `[{"op": "test", "value": "foo", "path": "/metadata/finalizers/-1"}]`,
+		},
 	} {
 		p := &patcher{
 			patchType:  types.JSONPatchType,
@@ -253,6 +257,7 @@ func TestJSONPatch(t *testing.T) {
 		codec := codecs.LegacyCodec(examplev1.SchemeGroupVersion)
 		pod := &examplev1.Pod{}
 		pod.Name = "podA"
+		pod.ObjectMeta.Finalizers = []string{"foo"}
 		versionedJS, err := runtime.Encode(codec, pod)
 		if err != nil {
 			t.Errorf("%s: unexpected error: %v", test.name, err)
diff --git a/staging/src/k8s.io/kubectl/pkg/cmd/util/helpers_test.go b/staging/src/k8s.io/kubectl/pkg/cmd/util/helpers_test.go
index 7cf0d70832b..955532ca9c8 100644
--- a/staging/src/k8s.io/kubectl/pkg/cmd/util/helpers_test.go
+++ b/staging/src/k8s.io/kubectl/pkg/cmd/util/helpers_test.go
@@ -289,6 +289,26 @@ func TestJSONPatch(t *testing.T) {
 			fragment:  `[ {"op": "add", "path": "/metadata/labels/foo", "value": "bar"} ]`,
 			expectErr: true,
 		},
+		{
+			obj: &corev1.Pod{
+				ObjectMeta: metav1.ObjectMeta{
+					Name:       "foo",
+					Finalizers: []string{"foo", "bar", "test"},
+				},
+			},
+			fragment: `[ {"op": "replace", "path": "/metadata/finalizers/-1", "value": "baz"} ]`,
+			expected: &corev1.Pod{
+				TypeMeta: metav1.TypeMeta{
+					Kind:       "Pod",
+					APIVersion: "v1",
+				},
+				ObjectMeta: metav1.ObjectMeta{
+					Name:       "foo",
+					Finalizers: []string{"foo", "bar", "baz"},
+				},
+				Spec: corev1.PodSpec{},
+			},
+		},
 	}
 
 	codec := runtime.NewCodec(scheme.DefaultJSONEncoder(),