需要确保使用的mockito和bloc_test的版本兼容，并在when().thenAnswer()中添加异步回调。

示例代码：

dependencies: bloc_test: ^7.1.1 mockito: ^5.0.0

// 需要确保使用mockito和bloc_test的版本兼容 // 在这个例子中使用的是mockito 5.0.0和bloc_test 7.1.1 test('Test bloc with mockito', () async { final mockRepository = MockRepository(); when(mockRepository.getData()).thenAnswer((_) async => 'Mock Data');

final bloc = MyBloc(mockRepository);

expectLater( bloc.stream, emitsInOrder([ MyInitialState(), MyLoadingState(), MyLoadedState('Mock Data'), ]));

bloc.add(MyEvent()); });

class MockRepository extends Mock implements Repository {}

class MyBloc extends Bloc { final Repository repository;

MyBloc(this.repository) : super(MyInitialState());

@override Stream mapEventToState(MyEvent event) async* { if (event is MyEvent) { yield MyLoadingState(); try { final data = await repository.getData(); yield MyLoadedState(data); } catch (e) { yield MyErrorState(e.toString()); } } } }

class Repository { Future getData() async { await Future.delayed(Duration(seconds: 1)); return 'Real Data'; } }

class MyEvent {}

class MyState {}

class MyInitialState extends MyState {}

class MyLoadingState extends MyState {}

class MyLoadedState extends MyState { final String data;

MyLoadedState(this.data); }

class MyErrorState extends MyState { final String errorMessage;

MyErrorState(this.errorMessage); }