Merge pull request #40844 from k82cn/admin_deny

Automatic merge from submit-queue

Improve the code coverage of /plugin/pkg/admission/deny

part of #39559

refer to attachment for the coverage report: [combined-coverage.html.gz](https://github.com/kubernetes/kubernetes/files/746779/combined-coverage.html.gz)

plugin/pkg/admission/deny/admission_test.go

@@ -27,6 +27,17 @@ func TestAdmission(t *testing.T) {
 	handler := NewAlwaysDeny()
 	err := handler.Admit(admission.NewAttributesRecord(nil, nil, api.Kind("kind").WithVersion("version"), "namespace", "name", api.Resource("resource").WithVersion("version"), "subresource", admission.Create, nil))
 	if err == nil {
-		t.Errorf("Expected error returned from admission handler")
+		t.Error("Expected error returned from admission handler")
+	}
+}
+
+func TestHandles(t *testing.T) {
+	handler := NewAlwaysDeny()
+	tests := []admission.Operation{admission.Create, admission.Connect, admission.Update, admission.Delete}
+
+	for _, test := range tests {
+		if !handler.Handles(test) {
+			t.Errorf("Expected handling all operations, including: %v", test)
+		}
 	}
 }