Question

我对Jasmine和Angular的单元测试很新，所以请耐心等待我：）

我正在尝试为一个方法编写单元测试，该方法应该返回类型为ArtworkDetail的对象，但不希望服务进行实际的http调用。我听说过嘲笑数据和嘲弄服务，但我不知道如何自己做。我在单元测试文件中制作模拟对象还是创建模拟服务？任何指针都表示赞赏！

app.component.ts

public setArtworkDetail(id: string): void {
  this.details = undefined;

  this.artworksService.getArtworkDetail(id)
    .subscribe((detailData: ArtworkDetail) => {
      this.details = detailData;
    });
}

app.component.spec.ts

describe('AppComponent', () => {
  beforeEach(async(() => {
    TestBed.configureTestingModule({
      declarations: [
        AppComponent,
        IndexComponent,
        DetailsComponent,
        NavbarComponent
      ],
      providers: [
        {provide: ArtworksService, class: MockArtworksService}
      ]
    }).compileComponents();
  }));

  it('should return an ArtworkDetail when calling setArtworkDetail()', (() => {

  ...

  }));

艺术品-detail.model.ts

export interface ArtworkDetail {
  id: string;
  title: string;
  url: string;
  year: number;
  description: string;
  artist: string;
}

Answer 1

您说明要使用模拟是正确的。 Angular实际上有一个很好的tutorial page on it

一般要点是，您在before方法中提供此类，然后让它返回相关数据。 IMO是该页面的最佳例子：

  it('getHeroes() should return some heroes', fakeAsync(() => {
       let result: String[];
       this.heroService.getHeroes().then((heroes: String[]) => result = heroes);
       this.lastConnection.mockRespond(new Response(new ResponseOptions({
         body: JSON.stringify({data: [HERO_ONE, HERO_TWO]}),
       })));
       tick();
       expect(result.length).toEqual(2, 'should contain given amount of heroes');
       expect(result[0]).toEqual(HERO_ONE, ' HERO_ONE should be the first hero');
       expect(result[1]).toEqual(HERO_TWO, ' HERO_TWO should be the second hero');
     }));

要验证调用某个方法，您需要创建a spy。创建后，您只需致电

expect(ArtworkServiceSpy.setArtworkDetail.calls.count())
      .toBe(1, 'spy method was called once');

Angular Jasmine：单元测试正在调用服务而不执行实际http调用的方法

1 个答案: