我的Angular 8 Web应用程序具有一个组件,该组件根据路由执行不同的操作。在ngOnInit
中,我使用路由数据来检查是否存在cached
参数。我正在尝试编写一个将cached
设置为true的单元测试,以便它进入if
中的ngOnInit
语句中,但是它不起作用。我在做什么错了?
home.component.ts
cached = false;
constructor(private backend: APIService, private activatedRoute: ActivatedRoute) { }
ngOnInit() {
this.cached = this.activatedRoute.snapshot.data['cached'];
if (this.cached)
{
this.getCached();
}
else
{
this.fetchFromAPI();
}
}
home.component.spec.ts
describe('HomeComponent', () => {
let component: HomeComponent;
let fixture: ComponentFixture<HomeComponent>;
let service: APIService;
beforeEach(async(() => {
TestBed.configureTestingModule({
imports: [
HttpClientTestingModule,
RouterTestingModule,
],
declarations: [
HomeComponent,
],
providers: [
APIService
]
})
.compileComponents();
}));
beforeEach(() => {
fixture = TestBed.createComponent(HomeComponent);
component = fixture.componentInstance;
service = TestBed.get(APIService);
fixture.detectChanges();
});
it('should create', () => {
expect(component).toBeTruthy();
});
it('should go into if cached statement', fakeAsync(() => {
component.cached = true;
component.ngOnInit();
const dummyData = [
{ id: 1, name: 'testing' }
];
spyOn(service, 'fetchCachedData').and.callFake(() => {
return from([dummyData]);
});
expect(service.fetchCachedData).toHaveBeenCalled();
}));
})
路由器模块
const routes: Routes = [
{ path: 'home', component: HomeComponent },
{ path: '', redirectTo: 'home', pathMatch: 'full' },
{ path: 'view-cache', component: HomeComponent, data: {cached: true}},
];
答案 0 :(得分:1)
您可以在测试中模拟ActivatedRoute
。在规范文件的ActivatedRoute
中使用所需的值创建一个对象。
const mockActivatedRoute = {
snapshot: {
data: {
cached: true
}
}
}
在TestBed.configureTestingModule
中,提供此值而不是ActivatedRoute
。如下修改您的提供商:
providers: [
APIService,
{ provide: ActivatedRoute, useValue: mockActivatedRoute }
]
现在,您的组件将在单元测试期间将这个模拟值用于ActivatedRoute。