final bool inSoundMode = <int?>[] is! List<int>;
main() {}

class Class1 {
  final int field;
  Class1([this.field = 42]);
}

class Class2 {
  final int field;
  Class2({this.field: 42});
}

void testDefaultValues() {}
expect(expected, actual) {}
throws(Function() f, {bool inSoundModeOnly: false}) {}