使用Karma的Angular测试中的错误：未捕获（承诺）：错误：没有SessionUtil的提供程序

Question

I am trying to write some tests for my Angular application. I am writing my tests in Jasmin / Karma / PhantomJS and I keep getting an error which makes all my tests fail, this is Error: No provider for SessionUtil!

SessionUtil is a Utility Class / Service that has numerous public methods. in my main.component.ts file I inject it into my construtor like so

constructor(@Inject(SessionUtil) private sessionUtil: SessionUtil) 

and this is my test file (not all of it, just where I declare everything and import my services, etc)

describe('MainComponent', () => {
  let componentFixture: ComponentFixture<MainComponent>;
  let instance: any;
  let element: any;
  let sessionUtil: SessionUtil;
  let spyLocalizationsService;
  const firstLanguage = 'en-US';
  const secondLanguage = 'de-DE';
  const unknownLanguage = 'xx-XX';

  beforeEach(async(() => {

    spyLocalizationsService = sinon.createStubInstance(LocalizationsService);
    spyLocalizationsService.changeLanguage.withArgs(firstLanguage, sinon.match.any, sinon.match.any).callsArg(1);
    spyLocalizationsService.changeLanguage.withArgs(secondLanguage, sinon.match.any, sinon.match.any).callsArg(1);
    spyLocalizationsService.changeLanguage.withArgs(unknownLanguage, sinon.match.any, sinon.match.any).callsArg(2);
    spyLocalizationsService.getSupportedLanguages.returns([firstLanguage, secondLanguage]);

    (sinon.stub(spyLocalizationsService, 'currentLanguage') as any).get(() => firstLanguage);

    // Allows overriding default providers, directives, pipes
    TestBed.configureTestingModule({
      imports: [
        RouterTestingModule.withRoutes([
          // some Paths
        ]),
        TranslateI18NextTestingModule.forRoot(),
        AuthTestingModule.forRoot(),
        NoopAnimationsModule,
        MaterialModule
      ],
      declarations: [
        MainComponent,
        DummyComponent
      ],
      schemas:
        [CUSTOM_ELEMENTS_SCHEMA],
      providers:
        [{provide: LocalizationsService, useValue: spyLocalizationsService},
         {provide: MATERIAL_COMPATIBILITY_MODE, useValue: true}]
    }).compileComponents().then(() => {
      componentFixture = TestBed.createComponent(MainComponent);
      element = componentFixture.nativeElement;
      instance = componentFixture.componentInstance; // BannerComponent test instance
      sessionUtil = componentFixture.debugElement.injector.get(SessionUtil);
    });
  }));

  const isAuthenticated = () => Promise.resolve({
    isAuthenticated: true,
    username: 'Max Musterman'
  });

describe('on init', () => {

beforeEach(async(() => {
  sinon.stub(sessionUtil, 'isAuthenticated').returns(isAuthenticated());
}));

when I run my tests I just get the following error and none of my tests run, Uncaught (in promise): Error: No provider for SessionUtil! I am obviously doing something wrong. I tried to inject the SessionUtil in the TestBed.configureTestingModule object providers array, but this gave me just as many problems. Can anyone see how I am injecting this incorrectly?

Any advice would be appreciated!

Answer 1

{provide: SessionUtil, useValue: sessionUtil}

而且您需要使用存根启动sessionUtil