Code generation for complex types with default value produces warning #1170
Description
When having a constructor with a not nullable parameter that is a complex type and has a default value, flutter gives me the following warning:
: Warning: Operand of null-aware operation '??' has type 'Duration' which excludes null.
lib/model/my_class.g.dart:13
- 'Duration' is from 'dart:core'.
d: Duration(microseconds: json['d'] as int) ?? Duration.zero,
See the following example code to reproduce it:
part 'my_class.g.dart';
@JsonSerializable()
class MyClass {
const MyClass({
required this.a,
required this.c,
this.b = '',
this.d = Duration.zero,
});
factory MyClass.fromJson(Map<String, dynamic> json) =>
_$MyClassFromJson(json);
final String a, b;
final Duration c, d;
Map<String, dynamic> toJson() => _$MyClassToJson(this);
}// GENERATED CODE - DO NOT MODIFY BY HAND
part of 'my_class.dart';
// **************************************************************************
// JsonSerializableGenerator
// **************************************************************************
MyClass _$MyClassFromJson(Map<String, dynamic> json) => MyClass(
a: json['a'] as String,
c: Duration(microseconds: json['c'] as int),
b: json['b'] as String? ?? '',
d: Duration(microseconds: json['d'] as int) ?? Duration.zero,
);
Map<String, dynamic> _$MyClassToJson(MyClass instance) => <String, dynamic>{
'a': instance.a,
'b': instance.b,
'c': instance.c.inMicroseconds,
'd': instance.d.inMicroseconds,
};
flutter --version
Flutter 3.0.2 • channel stable • https://github.com/flutter/flutter.git
Framework • revision cd41fdd495 (vor 4 Wochen) • 2022-06-08 09:52:13 -0700
Engine • revision f15f824b57
Tools • Dart 2.17.3 • DevTools 2.12.2