Fix not being able to return UnmarshalTypeError when it should be returned

decode_interface.go

@@ -214,7 +214,7 @@ func (d *interfaceDecoder) decodeStream(s *stream, p unsafe.Pointer) error {
 		if u, ok := rv.Interface().(encoding.TextUnmarshaler); ok {
 			return decodeStreamTextUnmarshaler(s, u, p)
 		}
-		return &UnsupportedTypeError{Type: rv.Type()}
+		return d.errUnmarshalType(rv.Type(), s.totalOffset())
 	}
 	iface := rv.Interface()
 	ifaceHeader := (*interfaceHeader)(unsafe.Pointer(&iface))
@@ -241,6 +241,16 @@ func (d *interfaceDecoder) decodeStream(s *stream, p unsafe.Pointer) error {
 	return decoder.decodeStream(s, ifaceHeader.ptr)
 }
 
+func (d *interfaceDecoder) errUnmarshalType(typ reflect.Type, offset int64) *UnmarshalTypeError {
+	return &UnmarshalTypeError{
+		Value:  typ.String(),
+		Type:   typ,
+		Offset: offset,
+		Struct: d.structName,
+		Field:  d.fieldName,
+	}
+}
+
 func (d *interfaceDecoder) decode(buf []byte, cursor int64, p unsafe.Pointer) (int64, error) {
 	runtimeInterfaceValue := *(*interface{})(unsafe.Pointer(&interfaceHeader{
 		typ: d.typ,
@@ -254,7 +264,7 @@ func (d *interfaceDecoder) decode(buf []byte, cursor int64, p unsafe.Pointer) (i
 		if u, ok := rv.Interface().(encoding.TextUnmarshaler); ok {
 			return decodeTextUnmarshaler(buf, cursor, u, p)
 		}
-		return 0, &UnsupportedTypeError{Type: rv.Type()}
+		return 0, d.errUnmarshalType(rv.Type(), cursor)
 	}
 
 	iface := rv.Interface()

decode_string.go

@@ -231,6 +231,8 @@ func (d *stringDecoder) decodeStreamByte(s *stream) ([]byte, error) {
 			continue
 		case '[':
 			return nil, d.errUnmarshalType("array", s.totalOffset())
+		case '{':
+			return nil, d.errUnmarshalType("object", s.totalOffset())
 		case '-', '0', '1', '2', '3', '4', '5', '6', '7', '8', '9':
 			return nil, d.errUnmarshalType("number", s.totalOffset())
 		case '"':
@@ -257,6 +259,8 @@ func (d *stringDecoder) decodeByte(buf []byte, cursor int64) ([]byte, int64, err
 			cursor++
 		case '[':
 			return nil, 0, d.errUnmarshalType("array", cursor)
+		case '{':
+			return nil, 0, d.errUnmarshalType("object", cursor)
 		case '-', '0', '1', '2', '3', '4', '5', '6', '7', '8', '9':
 			return nil, 0, d.errUnmarshalType("number", cursor)
 		case '"':

decode_test.go

@@ -2317,7 +2317,6 @@ var decodeTypeErrorTests = []struct {
 	{new(error), `true`},
 }
 
-/*
 func TestUnmarshalTypeError(t *testing.T) {
 	for _, item := range decodeTypeErrorTests {
 		err := json.Unmarshal([]byte(item.src), item.dest)
@@ -2327,7 +2326,6 @@ func TestUnmarshalTypeError(t *testing.T) {
 		}
 	}
 }
-*/
 
 var unmarshalSyntaxTests = []string{
 	"tru",