angular - 提供された模擬サービスからの応答を取得できません

Question

テスト モジュールで提供されているモック サービスからの応答を受信できません。

私は何かを省略していますか？

エラーが表示されます: TypeError: undefined is not a constructor (evaluating 'service.getUser.subscribe')*

class MockUserService {
  getUser: jasmine.createSpy('getUser').and.returnValue(Observable.of({'name': 'user1'})),
  getUser2: jasmine.createSpy('getUser2').and.returnValue(new BehaviorSubject({'name': 'user2'}))   
}

fdescribe('should use mocked services', () => {
  let component: TestComponent;
  let fixture: ComponentFixture<TestComponent>;
  let service;

  beforeEach(async(() => {
    TestBed.configureTestingModule({
      imports: [.....],
      providers: [{provide: UserService, useClass: MockUserService}],
      declarations: [TestComponent],
      schemas: [NO_ERRORS_SCHEMA]
    })
    .compileComponents();

    service = TestBed.get(UserService);
  }));

  beforeEach(() => {
    fixture = TestBed.createComponent(TestComponent);
    component = fixture.componentInstance;
  });

  it(`should provide mocked service`, () => {
     service.getUser.subscribe(user => {
       console.log(`user: ${user}`);
       expect(user.name).toBe('user1');
     });

    service.getUser2.subscribe(user => {
       console.log(`user: ${user}`);
       expect(user.name).toBe('user2');
     });
  });
});