我有这个试图模拟的 Angular 服务：@Injectable({ providedIn: 'root',})export class NotificationsService { private _notifications = new Subject （）; 民众

我正在尝试模拟这个 Angular 服务：

@Injectable({
  providedIn: 'root',
})
export class NotificationsService {
  private _notifications = new Subject<Notification>();
  public notifications: Observable<Notification> = this._notifications.asObservable();
  public crudNotifications: Observable<CrudNotification> = this._notifications.asObservable().pipe(
    filter(notification => notification.notificationType === 'crud-notification'),
    map(notification => notification as CrudNotification)
  );
//....
}

我刚刚将其迁移到 Jest，并试图弄清楚当我的测试服务尝试访问时如何模拟返回自定义可观察对象 NotificationsService.crudNotifications

目前，我有这个：

describe('OrganizationUsersService', () => {
  let organizationUsersService: OrganizationUsersService;
  let crudNotifications!: Subject<CrudNotification>;
  let notificationServiceMock!: Spy<NotificationsService>
  let storeMock!: Spy<Store>;
  let httpTestingController! :HttpTestingController;
  
  beforeEach(()=>{
    

    TestBed.configureTestingModule({
      providers:[
      {provide: NotificationsService, useValue: createSpyFromClass(NotificationsService)},
      {provide: Store, useValue:     createSpyFromClass(Store)  },
      {provide: Router, useValue:     createSpyFromClass(Router)  },
      provideHttpClient(),
      provideHttpClientTesting(),
      ]
    })
    httpTestingController = TestBed.inject(HttpTestingController);
    notificationServiceMock = TestBed.inject<any>(NotificationsService);
    storeMock = TestBed.inject<any>(Store);

    //Common mocked stuff behavior for every methods here    
    crudNotifications = new Subject<CrudNotification>();
    notificationServiceMock.crudNotifications = crudNotifications.asObservable();

    storeMock.dispatch.mockReturnValue(of());
    storeMock.select.mockReturnValue(of({ id: 'some-id' }));

    //Finally create the service to test:    
    organizationUsersService = TestBed.inject(OrganizationUsersService);
  })

    fit('should refresh the store when the backend inform a new role attribution has been added for the current organization id', fakeAsync(() => {
    //Arrange
    organizationUsersService.initialize(); //Required to register

    //Act
    crudNotifications.next({
      dataType: 'organization.role-attribution',
      operationType: 'add',
      id: 'some-id',
      notificationType: 'crud-notification',
    });
    tick();

    //Assert
    httpTestingController.expectOne(environment.backendUrl + 'some/stuff').flush({});
    httpTestingController.expectOne(environment.backendUrl + 'some/other/stuff').flush({});

    expect(storeMock.dispatch).toHaveBeenCalledWith(expect.any(SetLoadingAction));
    organizationUsersService.dispose();
  }));
}));

这不起作用，因为我尝试设置的可观察对象没有启用 Spy 方法。我尝试过这个：

notificationServiceMock.crudNotifications.mockReturnValue(crudNotifications);

但公共字段上不存在 mockReturnValue 方法。

有没有办法在公共领域模拟价值？

• object-literal
• ng-modules