angular - 如何测试返回多个操作的效果

Question

我有一个效果，先返回 Action A，然后返回 Action B

@Effect() myEffect$: Observable <Action> = this.actions$
  .ofType('MY_ACTION')
  .switchMap(() => Observable.of(
    // subscribers will be notified
    { type: 'ACTION_ONE' },
    // subscribers will be notified (again ...)
    { type: 'ACTION_TWO' }
  ));

如何测试两个连续的返回操作？

it('should return action one then action two', () => {
  runner.queue(new myAction());
  const expectedResult = twoSuccesiveActions;
  sessionEffect.myEffect$.subscribe(result => {
    // how do I test those two succesively returned actions
    expect(result).toEqual(expectedResult);
  });
});

Answer 1

您可以将一个与 take(1) 一起使用，另一个与 skip(1) 一起使用:

it('should return action one then action two', () => {
  const expectedResult = twoSuccesiveActions;
  sessionEffect.myEffect$.take(1).subscribe(result => {
    // first action
    expect(result).toEqual(expectedResult);
  });

  sessionEffect.myEffect$.skip(1).take(1).subscribe(result => {
    // second action
    expect(result).toEqual(expectedResult);
  });

  runner.queue(new myAction());
});

无论如何我建议您使用take(1) 如果您不手动取消订阅以确保不会泄漏到其他测试等...