单元测试 queryParams 订阅 (Angular5)答案

【问题标题】：Unit test queryParams subscription (Angular5)单元测试 queryParams 订阅 (Angular5)
【发布时间】：2018-11-03 16:53:00
【问题描述】：

我在测试 ActivatedRoute queryParams 订阅中的逻辑时遇到问题。

constructor(private router: Router, private route: ActivatedRoute, private auth: AuthService) {}

ngOnInit(): void {
  this.route.queryParams.subscribe((params:any) => {
    if(params['data']) {
      this.handle(params['data']);
    } else {
      if (this.auth.isAuthenticated()) {
        this.router.navigate(['/home']);
      }
    }
  });
}

我想测试：

如果在提供 params['data'] 模拟时触发 this.handle()
如果没有参数并且this.auth.isAuthenticated() 返回true，则调用this.router.navigate

我已经尝试了多种方法，但我的想法已经不多了。

我的测试文件：

describe('TestComponent', () => {
  let component: TestComponent;
  let fixture: ComponentFixture<TestComponent>;

  const mockService = {
    navigate: jasmine.createSpy('navigate'),
    isAuthenticated: jasmine.createSpy('isAuthenticated'),
    queryParams: jasmine.createSpy('queryParams')
  };

  beforeEach(async(() => {
    TestBed.configureTestingModule({
      declarations: [TestComponent],
      providers: [
        { provide: Router, useValue: mockService },
        { provide: ActivatedRoute, useValue: mockService },
        { provide: AuthService, useValue: mockService }
      ]
    }).compileComponents();

    fixture = TestBed.createComponent(TestComponent);
    component = fixture.componentInstance;

    mockService.navigate.calls.reset();
  }));

  it('should create the test component', () => {
    expect(component).toBeTruthy();
  });

  it('should navigate away when authenticated', () => {
    mockService.isAuthenticated.and.returnValue(true);
    mockService.queryParams.and.callFake((data, params) => new Observable(o => o.next({ params: {} })));
    component.ngOnInit();
    expect(mockService.navigate).toHaveBeenCalledWith(['/home']);
  });
});

但是我得到TypeError: this.route.queryParams.subscribe is not a function。我知道mockService.isAuthenticated.and.returnValue(true); 工作正常，因为在使用订阅参数之前，我在ngOnInit() 中只有这个 if 语句。

我已尝试将 mockService 更改为：

const mockService = {
  navigate: jasmine.createSpy('navigate'),
  isAuthenticated: jasmine.createSpy('isAuthenticated'),
  queryParams: {
    subscribe: jasmine.create('subscribe')
  }
};

我也尝试过：

const mockService = {
  navigate: jasmine.createSpy('navigate'),
  isAuthenticated: jasmine.createSpy('isAuthenticated'),
  queryParams: {
    subscribe: Observable.of({ params: {} })
  }
};

但没有成功，对于最后两个我得到Expected spy navigate to have been called with [ [ '/home' ] ] but it was never called.

那么有人知道如何正确测试 querParams 订阅中的逻辑吗？

【问题讨论】：

标签： javascript angular unit-testing karma-jasmine

【解决方案1】：

我不能说现在回答这个问题是否为时已晚，但也许它会帮助新的谷歌员工......

我设法通过这种方式解决了这个问题：

class ActivatedRouteMock {
  queryParams = new Observable(observer => {
    const urlParams = {
      param1: 'some',
      param2: 'params'
    }
    observer.next(urlParams);
    observer.complete();
  });
}

beforeEach(async(() => {
  TestBed.configureTestingModule({
    imports: [
      HttpClientTestingModule
    ],
    providers: [
      HttpClient,
      HttpHandler,
      ControlContainer,
      {
        provide: ActivatedRoute,
        useClass: ActivatedRouteMock
      }
    ]
  }).compileComponents();

  injector = getTestBed();
  httpMock = injector.get(HttpTestingController);
}));

这允许您在 .subscribe(() => {}) 方法中声明逻辑..

希望对你有帮助

【讨论】：

【解决方案2】：

你可以在 useValue 中使用 rxjs observable 来模拟它。

const router = {
  navigate: jasmine.createSpy('navigate')
};
beforeEach(async(() => {    
TestBed.configureTestingModule({
  imports: [
    RouterTestingModule.withRoutes([]),
    RouterTestingModule,
    PlanPrimengModule
  ],
  declarations: [YourComponent],
  schemas: [CUSTOM_ELEMENTS_SCHEMA],
  providers: [
    provideMockStore(),
    {
      provide: ActivatedRoute,
      useValue: {
        queryParams: of({
          param1: "value1",
          param1: "value2"
        })
      }
    },
    { provide: Router, useValue: router }
  ]
}).compileComponents();   }));

【讨论】：