From e3bca5adc7e7e5460c5f867468b27a3a9f04b438 Mon Sep 17 00:00:00 2001
From: Andrea Nodari <and.nodari@gmail.com>
Date: Wed, 3 Jun 2020 17:04:53 +0200
Subject: [PATCH] Add test case for a pod becoming schedulable when another pod
 is deleted

---
 test/integration/scheduler/predicates_test.go | 41 +++++++++++++++----
 1 file changed, 34 insertions(+), 7 deletions(-)

diff --git a/test/integration/scheduler/predicates_test.go b/test/integration/scheduler/predicates_test.go
index b889b3b5d12..728350f7f18 100644
--- a/test/integration/scheduler/predicates_test.go
+++ b/test/integration/scheduler/predicates_test.go
@@ -24,6 +24,7 @@ import (
 
 	v1 "k8s.io/api/core/v1"
 	apierrors "k8s.io/apimachinery/pkg/api/errors"
+	"k8s.io/apimachinery/pkg/api/resource"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 	"k8s.io/apimachinery/pkg/util/wait"
 	utilfeature "k8s.io/apiserver/pkg/util/feature"
@@ -1041,16 +1042,16 @@ var (
 func TestUnschedulablePodBecomesSchedulable(t *testing.T) {
 	tests := []struct {
 		name   string
-		init   func(kubernetes.Interface) error
+		init   func(kubernetes.Interface, string) error
 		pod    *pausePodConfig
-		update func(kubernetes.Interface) error
+		update func(kubernetes.Interface, string) error
 	}{
 		{
 			name: "node gets added",
 			pod: &pausePodConfig{
 				Name: "pod-1",
 			},
-			update: func(cs kubernetes.Interface) error {
+			update: func(cs kubernetes.Interface, _ string) error {
 				_, err := createNode(cs, "node-added", nil)
 				if err != nil {
 					return fmt.Errorf("cannot create node: %v", err)
@@ -1060,7 +1061,7 @@ func TestUnschedulablePodBecomesSchedulable(t *testing.T) {
 		},
 		{
 			name: "node gets taint removed",
-			init: func(cs kubernetes.Interface) error {
+			init: func(cs kubernetes.Interface, _ string) error {
 				node, err := createNode(cs, "node-tainted", nil)
 				if err != nil {
 					return fmt.Errorf("cannot create node: %v", err)
@@ -1074,7 +1075,7 @@ func TestUnschedulablePodBecomesSchedulable(t *testing.T) {
 			pod: &pausePodConfig{
 				Name: "pod-1",
 			},
-			update: func(cs kubernetes.Interface) error {
+			update: func(cs kubernetes.Interface, _ string) error {
 				taint := v1.Taint{Key: "test", Value: "test", Effect: v1.TaintEffectNoSchedule}
 				if err := testutils.RemoveTaintOffNode(cs, "node-tainted", taint); err != nil {
 					return fmt.Errorf("cannot remove taint off node: %v", err)
@@ -1082,6 +1083,32 @@ func TestUnschedulablePodBecomesSchedulable(t *testing.T) {
 				return nil
 			},
 		},
+		{
+			name: "other pod gets deleted",
+			init: func(cs kubernetes.Interface, ns string) error {
+				nodeResources := &v1.ResourceList{
+					v1.ResourcePods: *resource.NewQuantity(1, resource.DecimalSI),
+				}
+				_, err := createNode(cs, "node-scheduler-integration-test", nodeResources)
+				if err != nil {
+					return fmt.Errorf("cannot create node: %v", err)
+				}
+				_, err = createPausePod(cs, initPausePod(&pausePodConfig{Name: "pod-to-be-deleted", Namespace: ns}))
+				if err != nil {
+					return fmt.Errorf("cannot create pod: %v", err)
+				}
+				return nil
+			},
+			pod: &pausePodConfig{
+				Name: "pod-1",
+			},
+			update: func(cs kubernetes.Interface, ns string) error {
+				if err := deletePod(cs, "pod-to-be-deleted", ns); err != nil {
+					return fmt.Errorf("cannot delete pod: %v", err)
+				}
+				return nil
+			},
+		},
 		// TODO(#91111): Add more test cases.
 	}
 	for _, tt := range tests {
@@ -1090,7 +1117,7 @@ func TestUnschedulablePodBecomesSchedulable(t *testing.T) {
 			defer testutils.CleanupTest(t, testCtx)
 
 			if tt.init != nil {
-				if err := tt.init(testCtx.ClientSet); err != nil {
+				if err := tt.init(testCtx.ClientSet, testCtx.NS.Name); err != nil {
 					t.Fatal(err)
 				}
 			}
@@ -1102,7 +1129,7 @@ func TestUnschedulablePodBecomesSchedulable(t *testing.T) {
 			if err := waitForPodUnschedulable(testCtx.ClientSet, pod); err != nil {
 				t.Errorf("Pod %v got scheduled: %v", pod.Name, err)
 			}
-			if err := tt.update(testCtx.ClientSet); err != nil {
+			if err := tt.update(testCtx.ClientSet, testCtx.NS.Name); err != nil {
 				t.Fatal(err)
 			}
 			if err := testutils.WaitForPodToSchedule(testCtx.ClientSet, pod); err != nil {