开玩笑地创建从存储角度读取的属性的模拟

Question

我正在使用 Angular、NgRx 和 Jest。

我正在使用从商店读取的服务

export class MyFacade {
  configuration$ = this.store.select(selectors.selectConfiguration);
}

我在我的规范文件中使用它来测试效果。我已经创建了像这样实现它的模拟类

export class MyMockFacade {
  configuration$ = of(configObject);
}

我的规格文件看起来像这样：

describe('Config Effects', () => {
  const mockStore = new MockStore();
    ....
  const mockFacade  = new MyMockFacade();

  let actions;
  let effects: ConfigEffects;

  beforeAll(() => {
    Object.defineProperty(window, 'location', {
      configurable: true,
      value: { reload: jest.fn() }
    });
  });
  beforeEach(() => {
    TestBed.configureTestingModule({
     
      providers: [
        ConfigEffects,
        HttpClientModule,
        provideMockActions(() => actions),
        { provide: Store, useValue: mockStore },
        ...
        { provide: MyFacade , useValue: mockFacade  },
      ]
    });
    effects = TestBed.inject(ConfigEffects);
  });
});

我希望能够更改测试中配置$返回的值。我怎样才能实现它

 it('should call ....', () => {
    
    //I would like to be able to assigned new value here!

    
      expect(effects.loadXXX$).toSatisfyOnFlush(() => {
        ...
      });
    });

Answer 1

将

configuration$

设为

BehaviorSubject

，以便您可以指定它应发出的值：

export class MyMockFacade {
  configuration$ = new BehaviorSubject<ConfigObject>(null);
}

it('should call ....', () => {
    mockFacade.configuration$.next(someConfigObject); 

    expect(effects.loadXXX$).toSatisfyOnFlush(() => {
      ...
    });
});