angular2 / jasmine注入模拟服务而不是调用间谍

Question

尝试使用jasmine对angular2应用程序进行单元测试，但是当我尝试注入服务时，间谍不会接受注入的调用。

测试套件：

import { TestBed, inject, tick, fakeAsync, ComponentFixture } from '@angular/core/testing';
import { By } from '@angular/platform-browser';
import { RouterTestingModule } from '@angular/router/testing';

import { RoomComponent } from './room.component';

import { Room } from './room';
import { RoomService } from './room.service';
import { MockRoomService } from '../mock/mock.room.service';
import { BaseRequestOptions, Http, ConnectionBackend, Response, ResponseOptions } from '@angular/http';
import { MockBackend } from '@angular/http/testing';

...

beforeEach(fakeAsync(() => {
TestBed.configureTestingModule({
  declarations: [
    RoomComponent
  ],
  providers: [
    {
      provide: Http, useFactory: (backend: ConnectionBackend, defaultOptions: BaseRequestOptions) => {
        return new Http(backend, defaultOptions);
      },
      deps: [MockBackend, BaseRequestOptions]
    },
    RoomService,
    {provide: MockBackend, useClass: MockBackend},
    {provide: BaseRequestOptions, useClass: BaseRequestOptions}
  ],
  imports: [
    RouterTestingModule
  ]
})
.overrideComponent(RoomComponent, {
  set: {
    providers: [{provide: RoomService, useClass: MockRoomService}]
  }
})

...

it('should have rooms after getRooms', inject([RoomService], fakeAsync((mockRoomService: MockRoomService) => {
  let spy = spyOn(mockRoomService, 'getRooms').and.callThrough();
  fixture.detectChanges();
  tick();
  expect(spy).toHaveBeenCalled(); //Does not return true
  expect(component.rooms).toBeDefined();
})));

测试间谍自己的工作（使用模拟服务和直接调用），并且组件调用模拟服务而不是真实服务，返回测试数据：

LOG: 'ngInitified'
PhantomJS 2.1.1 (Windows 7 0.0.0): Executed 6 of 21 (skipped 3) SUCCESS (0 secs / 1.156 secs)
LOG: 'method reached'
PhantomJS 2.1.1 (Windows 7 0.0.0): Executed 6 of 21 (skipped 3) SUCCESS (0 secs / 1.156 secs)
LOG: 'mock service reached'
PhantomJS 2.1.1 (Windows 7 0.0.0): Executed 6 of 21 (skipped 3) SUCCESS (0 secs / 1.156 secs)
LOG: [Object{_id: '12', gitrepo: 'repository', channel: 'slack channel'}, Object{_id: '42', gitrepo: 'newrepo', channel: 'dev'}]
PhantomJS 2.1.1 (Windows 7 0.0.0): Executed 6 of 21 (skipped 3) SUCCESS (0 secs / 1.156 secs)
PhantomJS 2.1.1 (Windows 7 0.0.0) Component: Room should have rooms after getRooms FAILED
    Expected spy getRooms to have been called.

尝试过直接注入MockRoomService。 尝试将间谍放在RoomService对象上而不是模拟对象上。 没有回复间谍被召唤。

模拟服务：

import { Injectable } from '@angular/core';
import { Http } from '@angular/http';
import { Room } from '../room/room';

@Injectable()
export class MockRoomService {
    testData: Room[] = [{"_id":"12","gitrepo": "repository", "channel": "slack channel"}, {"_id":"42","gitrepo": "newrepo", "channel": "dev"}];

    constructor(http: Http) { }

    getRooms(): Promise<Room[]> {
        console.log("mock service reached");
        return new Promise((resolve, reject) => {
            resolve(this.testData);
        });
    }

...

真实服务：

import { Room } from './room';
import { Http, Headers, RequestOptions } from '@angular/http';

import 'rxjs/add/operator/toPromise';

import { Injectable } from '@angular/core';

@Injectable()
export class RoomService {
    constructor (private http: Http) {}

    getRooms(): Promise<Room[]> {
        console.log("real service reached");
        return this.http.get('api/rooms/get')
        .toPromise()
        .then(res => res.json() as Room[]);
    }

...

零件：

import { Component, OnInit } from '@angular/core';
import { Router } from '@angular/router';

import { Room } from './room';
import { RoomService } from './room.service';

@Component({
  selector: 'app-room',
  templateUrl: './room.component.html',
  styleUrls: ['./room.component.css'],
  providers: [RoomService]
})
export class RoomComponent implements OnInit {
  title = 'Repos and Channels';
  rooms: Room[] = [];
  constructor(
    private roomService: RoomService,
    private router: Router,
    ) {}

  ngOnInit() {
    console.log("ngInitified");
    this.getRooms();
  }

  getRooms() {
    console.log("method reached!");
    this.roomService.getRooms()
      .then(room => { this.rooms = room;
        console.log(this.rooms); }
    );
  }

...

救命？

Answer 1

你得到了RoomService提供商的错误实例。

it('should have rooms after getRooms', inject([RoomService], fakeAsync((mockRoomService: MockRoomService) => {
  let componentMockRoomService = fixture.debugElement.injector.get(RoomService);
  console.log(mockRoomService instanceof RoomService);         // true
  console.log(componentMockRoomService instanceof RoomService);// false

mockRoomService是来自root提供程序的实例，而您需要测试与您的组件相对应的类

所以这是你的考试

let componentMockRoomService = fixture.debugElement.injector.get(RoomService);
let spy = spyOn(componentMockRoomService, 'getRooms').and.callThrough();

Plunker示例