Merge pull request #124539 from Huang-Wei/ut-for-123465

test to catch illegal nodeNames returned by PreFilterResult

test/integration/scheduler/plugins/plugins_test.go

@@ -32,6 +32,7 @@ import (
 	"k8s.io/apimachinery/pkg/labels"
 	"k8s.io/apimachinery/pkg/runtime"
 	"k8s.io/apimachinery/pkg/types"
+	"k8s.io/apimachinery/pkg/util/sets"
 	"k8s.io/apimachinery/pkg/util/wait"
 	clientset "k8s.io/client-go/kubernetes"
 	listersv1 "k8s.io/client-go/listers/core/v1"
@@ -80,6 +81,7 @@ type PreFilterPlugin struct {
 	numPreFilterCalled   int
 	failPreFilter        bool
 	rejectPreFilter      bool
+	preFilterResultNodes sets.Set[string]
 }
 
 type ScorePlugin struct {
@@ -521,6 +523,9 @@ func (pp *PreFilterPlugin) PreFilter(ctx context.Context, state *framework.Cycle
 	if pp.rejectPreFilter {
 		return nil, framework.NewStatus(framework.Unschedulable, fmt.Sprintf("reject pod %v", pod.Name))
 	}
+	if len(pp.preFilterResultNodes) != 0 {
+		return &framework.PreFilterResult{NodeNames: pp.preFilterResultNodes}, nil
+	}
 	return nil, nil
 }
 
@@ -623,6 +628,7 @@ func TestPreFilterPlugin(t *testing.T) {
 		name                 string
 		fail                 bool
 		reject               bool
+		preFilterResultNodes sets.Set[string]
 	}{
 		{
 			name:   "disable fail and reject flags",
@@ -639,6 +645,18 @@ func TestPreFilterPlugin(t *testing.T) {
 			fail:   false,
 			reject: true,
 		},
+		{
+			name:                 "inject legal node names in PreFilterResult",
+			fail:                 false,
+			reject:               false,
+			preFilterResultNodes: sets.New[string]("test-node-0", "test-node-1"),
+		},
+		{
+			name:                 "inject legal and illegal node names in PreFilterResult",
+			fail:                 false,
+			reject:               false,
+			preFilterResultNodes: sets.New[string]("test-node-0", "non-existent-node"),
+		},
 	}
 
 	for _, test := range tests {
@@ -654,6 +672,7 @@ func TestPreFilterPlugin(t *testing.T) {
 
 			preFilterPlugin.failPreFilter = test.fail
 			preFilterPlugin.rejectPreFilter = test.reject
+			preFilterPlugin.preFilterResultNodes = test.preFilterResultNodes
 			// Create a best effort pod.
 			pod, err := testutils.CreatePausePod(testCtx.ClientSet,
 				testutils.InitPausePod(&testutils.PausePodConfig{Name: "test-pod", Namespace: testCtx.NS.Name}))