Add tests to ensure type coercion handles errors correctly

Author: liggitt

pkg/api/compatibility_test.go

@@ -116,15 +116,17 @@ func TestAllowedGrouplessVersion(t *testing.T) {
 
 func TestAllowedTypeCoercion(t *testing.T) {
 	ten := int64(10)
+	twenty := int32(10)
 
 	testcases := []struct {
-		name     string
-		input    []byte
-		into     runtime.Object
-		expected runtime.Object
+		name        string
+		input       []byte
+		into        runtime.Object
+		expected    runtime.Object
+		expectedErr string
 	}{
 		{
-			name: "string to number",
+			name: "string to int64",
 			input: []byte(`{
 				"kind":"Pod",
 				"apiVersion":"v1",
@@ -135,6 +137,36 @@ func TestAllowedTypeCoercion(t *testing.T) {
 				Spec:     v1.PodSpec{ActiveDeadlineSeconds: &ten},
 			},
 		},
+		{
+			name: "string to int64 malformed",
+			input: []byte(`{
+				"kind":"Pod",
+				"apiVersion":"v1",
+				"spec":{"activeDeadlineSeconds":"1.1"}
+			}`),
+			expectedErr: "read int64: unexpected character: \"",
+		},
+		{
+			name: "string to int32",
+			input: []byte(`{
+				"kind":"Pod",
+				"apiVersion":"v1",
+				"spec":{"priority":"10"}
+			}`),
+			expected: &v1.Pod{
+				TypeMeta: metav1.TypeMeta{Kind: "Pod", APIVersion: "v1"},
+				Spec:     v1.PodSpec{Priority: &twenty},
+			},
+		},
+		{
+			name: "string to int32 malformed",
+			input: []byte(`{
+				"kind":"Pod",
+				"apiVersion":"v1",
+				"spec":{"priority":"1.1"}
+			}`),
+			expectedErr: "read int32: unexpected character: \"",
+		},
 		{
 			name: "empty object to array",
 			input: []byte(`{
@@ -144,9 +176,18 @@ func TestAllowedTypeCoercion(t *testing.T) {
 			}`),
 			expected: &v1.Pod{
 				TypeMeta: metav1.TypeMeta{Kind: "Pod", APIVersion: "v1"},
-				Spec:     v1.PodSpec{Containers: []v1.Container{}},
+				Spec:     v1.PodSpec{Containers: nil},
 			},
 		},
+		{
+			name: "non-empty object to array fails",
+			input: []byte(`{
+				"kind":"Pod",
+				"apiVersion":"v1",
+				"spec":{"containers":{"name":"somevalue"}}
+			}`),
+			expectedErr: "v1.PodSpec.Containers: decode slice: expect [ or n, but found {",
+		},
 	}
 
 	for i := range testcases {
@@ -155,8 +196,14 @@ func TestAllowedTypeCoercion(t *testing.T) {
 			t.Run(tc.name, func(t *testing.T) {
 				s := jsonserializer.NewSerializer(jsonserializer.DefaultMetaFactory, legacyscheme.Scheme, legacyscheme.Scheme, false)
 				obj, _, err := s.Decode(tc.input, nil, tc.into)
-				if err != nil {
-					t.Error(err)
+				if err != nil || len(tc.expectedErr) > 0 {
+					if len(tc.expectedErr) == 0 {
+						t.Error(err)
+					} else if err == nil {
+						t.Errorf("expected error %q, got none", tc.expectedErr)
+					} else if !strings.Contains(err.Error(), tc.expectedErr) {
+						t.Errorf("expected error %q, got %q", tc.expectedErr, err.Error())
+					}
 					return
 				}
 				if !reflect.DeepEqual(obj, tc.expected) {