angular 2+ 中可观察的单元测试

Question

How to write the unit test case of the function which returns an observable

public notificationStream(): Observable<Notification> {
return this.notificationSubject.asObservable();

}

Answer 1

One approach can be like this

it('should check if notificationStream works correctly', () => {
   let mockResponse = { prepare your mock Response}
   this.component.notificationStream().subscribe(resoponse => {
     expect(response).toBe(mockResponse)
   })
   //call function from you component which contains following line 
   //this.notificationSubject.next(mockResponse);
  });

After subscription you will get all values in response that you pass to .next()