使用具有列表类型参数的 dart 类，如何使其具有等价性

Question

我正在使用新的库 bloc_test 进行颤振，并实现了以下测试

blocTest('should return ReservationsLoadSucess when the use case returns a list of reservationsList',

    build: () {
      when(mockGetReservations(any)).thenAnswer((_) async => Right(reservationsList));
      return ReservationBloc(getReservations: mockGetReservations);
    },
    act: (bloc) async {
      bloc.add(ReservationsRequested(user));
    },
    expect: [
      ReservationsInitial(),
      ReservationsLoadInProgress(),
      ReservationsLoadSuccess(reservationsList),
    ],
  );

这是ReservationsLoadSuccess的实现

class ReservationsLoadSuccess extends ReservationState {
  final List<Reservation> list;

  ReservationsLoadSuccess(this.list);

  @override
  List<Object> get props => [list];
}

ReservationState 扩展 Equatable 的地方 现在，在运行测试时，您会收到以下错误

should return ReservationsLoadSucess when the use case returns a list of reservationsList:

ERROR: Expected: [
            ReservationsInitial:ReservationsInitial,
            ReservationsLoadInProgress:ReservationsLoadInProgress,
            ReservationsLoadSuccess:ReservationsLoadSuccess
          ]
  Actual: [
            ReservationsInitial:ReservationsInitial,
            ReservationsLoadInProgress:ReservationsLoadInProgress,
            ReservationsLoadSuccess:ReservationsLoadSuccess
          ]
   Which: was ReservationsLoadSuccess:<ReservationsLoadSuccess> instead of ReservationsLoadSuccess:<ReservationsLoadSuccess> at location [2]

基本上说实际列表中位置 2 的状态 ReservationsLoadSuccess 不等于预期列表中的对等点。

我尝试在 ReservationsLoadSuccess 类中覆盖 == 运算符，如下所示

class ReservationsLoadSuccess extends ReservationState {
  final List<Reservation> list;

  ReservationsLoadSuccess(this.list);

  final Function eq = const ListEquality().equals;
  @override
  List<Object> get props => [];

  @override
  bool operator ==(Object other) =>
      identical(this, other) ||
      other is ReservationsLoadSuccess &&
          runtimeType == other.runtimeType &&
          eq(list, other.list);
}

但这似乎不起作用，运行测试仍然输出相同的错误。我让它工作的唯一方法是让 props 方法返回一个空列表或添加任何其他虚拟变量并将其传递给 props 列表。

有什么方法可以使类在列表参数方面相等？

Answer 1

您是否尝试查看包裹equatable。在应用 BLoC 模式时经常使用它。