fix: MarshalJSON method name in error message

cloudfoundry · Jan 13, 2021 · a571e0c · a571e0c
1 parent 3de60c7
commit a571e0c
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Showing 2 changed files with 6 additions and 5 deletions.
diff --git a/marshal.go b/marshal.go
@@ -133,16 +133,17 @@ func marshalMap(ctx context.Context, in reflect.Value) (out map[string]interface
 }
 
 func marshalJSONMarshaler(ctx context.Context, in reflect.Value) (interface{}, error) {
-	t := in.MethodByName("MarshalJSON").Call(nil)
+	const method = "MarshalJSON"
+	t := in.MethodByName(method).Call(nil)
 
 	if err := checkForError(t[1]); err != nil {
-		return nil, fmt.Errorf("error from MarshaJSON() call at %s: %w", ctx, err)
+		return nil, fmt.Errorf("error from %s() call at %s: %w", method, ctx, err)
 	}
 
 	var r interface{}
 	err := json.Unmarshal(t[0].Bytes(), &r)
 	if err != nil {
-		return nil, fmt.Errorf(`error parsing MarshaJSON() output "%s" at %s: %w`, t[0].Bytes(), ctx, err)
+		return nil, fmt.Errorf(`error parsing %s() output "%s" at %s: %w`, method, t[0].Bytes(), ctx, err)
 	}
 
 	return r, nil

diff --git a/marshal_test.go b/marshal_test.go
@@ -216,8 +216,8 @@ var _ = Describe("Marshal", func() {
 			expectToMarshal(struct{ I *implementsJSONMarshaler }{I: &implementsJSONMarshaler{bytes: []byte(`"hello"`)}}, `{"I":"hello"}`)
 			expectToMarshal(struct{ I *implementsJSONMarshaler }{I: (*implementsJSONMarshaler)(nil)}, `{"I":null}`)
 
-			expectToFail(struct{ I implementsJSONMarshaler }{I: implementsJSONMarshaler{err: errors.New("ouch")}}, `error from MarshaJSON() call at field "I" (type "jsonry_test.implementsJSONMarshaler"): ouch`)
-			expectToFail(struct{ I implementsJSONMarshaler }{I: implementsJSONMarshaler{}}, `error parsing MarshaJSON() output "" at field "I" (type "jsonry_test.implementsJSONMarshaler"): unexpected end of JSON input`)
+			expectToFail(struct{ I implementsJSONMarshaler }{I: implementsJSONMarshaler{err: errors.New("ouch")}}, `error from MarshalJSON() call at field "I" (type "jsonry_test.implementsJSONMarshaler"): ouch`)
+			expectToFail(struct{ I implementsJSONMarshaler }{I: implementsJSONMarshaler{}}, `error parsing MarshalJSON() output "" at field "I" (type "jsonry_test.implementsJSONMarshaler"): unexpected end of JSON input`)
 		})
 
 		It("marshals from named types and type aliases", func() {