Angular 测试在运行孤立时有效，但在与其他测试一起时失败

Question

我运行遇到了一个问题，即当它与我的应用程序中的所有其他测试一起运行时，测试一直失败。返回的错误是

Uncaught TypeError: You provided 'undefined' where a stream was expected. You can provide an Observable, Promise, Array, or Iterable. thrown

以下是题目中的两个类和测试文件

通知Class

export class Notification {
  message: string;
  category: string;
  clearAll: boolean = false;

  constructor(message: string, category?: string, clear?: boolean) {
    this.message = message;
    if (category) {
      this.category = category;
    }
    if (clear) {
      this.clearAll = clear;
    }
  }
}

通知服务Class

import { Injectable } from '@angular/core';
import { Observable } from 'rxjs/Observable';
import { Notification } from '../shared/notification';;


@Injectable({
  providedIn: 'root'
})
export class NotificationsService {
  notificationSubject: Subject<Notification>;
  notification$: Observable<any>;


  constructor() {
    this.notificationSubject = new Subject<Notification>();
    this.notification$ = this.notificationSubject.asObservable();
  }

  getNotificationObservable(): Observable<Notification> {
    return this.notification$;
  }

  /**
   * Method allowing a notification to be added so that subsribers can deal with is     according.
   * @param {Notification}notification
   */
  addNotifications(notification: Notification): void {
    this.notificationSubject.next(notification);
  }
}

notificationService.spec.ts

import { NotificationsService } from './notifications.service';

describe('NotificationService', () => {
  let service: NotificationsService;

  beforeEach(() => { service = new NotificationsService(); });

  it('to be created', () => {
    expect(1 === 1).toBeTruthy();
  });

});

如果我运行专注于此测试，它就会通过。即

fit('to be created', () => {
    expect(1 === 1).toBeTruthy();
  });

根据我所做的搜索，似乎有以下建议：

以前的测试没有正确地重置测试台，这就是为什么测试单独成功但在运行与其他
或者通知 Class 在测试之间共享属性，这导致了问题。

我怀疑第二个项目符号可能是这种情况，但我似乎无法确定问题所在。

Answer 1

我遇到了同样的问题。问题不在于失败的测试，而在于之前的测试。我最终删除了之前的测试，并解决了这个问题。

Angular 测试在运行孤立时有效，但在与其他测试一起时失败

Angular test works when run in isolation, but fails when when with other tets

karma-jasmine

angular

angular-test

Angular 测试在 运行 孤立时有效，但在与其他测试一起时失败

Angular test works when run in isolation, but fails when when with other tets

karma-jasmine

angular

angular-test

Angular 测试在运行孤立时有效，但在与其他测试一起时失败