FunnyGhost

  it('should throw if the backend returns an error ', () => {
    let bubblesUpTheError = false;
    serviceUnderTest.getFavoriteMovies().subscribe(() => {}, () => (bubblesUpTheError = true));

    const req = http.expectOne(environment.favoriteUrl, 'expected to make a request');
    expect(req.request.method).toEqual('GET');
    req.flush('ERROR', { status: 500, statusText: 'Internal server error' });

    expect(bubblesUpTheError).toBeTruthy();
    http.verify();

FunnyGhost

export class FavoriteMoviesService {
  constructor(private http: HttpClient) {}

  getFavoriteMovies(): Observable<Movie[]> {
    return this.http.get<Movie[]>(environment.favoriteUrl);
  }
}

FunnyGhost

describe('FavoriteMoviesService', () => {
  let serviceUnderTest: FavoriteMoviesService;
  let http: HttpTestingController;

  beforeEach(() => {
    TestBed.configureTestingModule({
      imports: [HttpClientTestingModule],
      providers: [FavoriteMoviesService]
    });

FunnyGhost

const favoriteUrl = 'test.favorite.com';

export const environment = {
  production: false,
  favoriteUrl
};

FunnyGhost

  getFavoriteMovies(): Observable<Movie[]> {
    return of([
      { title: 'Interstellar' } as Movie,
      { title: 'The Green Book' } as Movie,
      { title: 'Dark Knight' } as Movie
    ]);
  }

FunnyGhost

  it('should return the favorite movies', () => {
    let result: Movie[] = [];
    serviceUnderTest.getFavoriteMovies().subscribe(data => {
      result = data;
    });

    expect(result).toEqual(moviesToUse);
  });

FunnyGhost

const moviesToUse = [
  { title: 'Interstellar' } as Movie,
  { title: 'The Green Book' } as Movie,
  { title: 'Dark Knight' } as Movie
];

describe('FavoriteMoviesService', () => {
  let serviceUnderTest: FavoriteMoviesService;

  beforeEach(() => {

FunnyGhost

export class FavoriteMoviesService {
  constructor() {}

  getFavoriteMovies(): Observable<Movie[]> {
    return of([]);
  }
}

FunnyGhost

<div class="error" *ngIf="error">
  {{ error }}
</div>

FunnyGhost

  ngOnInit() {
    this.favoriteMovies$ = this.favoriteMovieService.getFavoriteMovies().pipe(
      catchError((error: any) => {
        this.error = error;

        return of([]);
      })
    );
  }