为 HttpClient 帖子创建间谍会创建返回值错误

Question

我有一个将HttpClient服务作为值的服务，我想监视post那个类的方法，所以我创建了一个看起来像这样的间谍：spyOn(httpClient, 'post').and.returnValue(() => new Subject<any>().asObservable());但是，我收到以下错误：Argument of type '() => Observable<any>' is not assignable to parameter of type 'Observable<unknown>'.  Type '() => Observable<any>' is missing the following properties from type 'Observable<unknown>': _isScalar, source, operator, lift, and 6 more.这是它来自的规范：describe('GraphQLClientService', () => {  let service: GraphQLClientService;  let httpClient: HttpClient;  let postSpy: any;  beforeEach(() => {    httpClient = jasmine.createSpyObj('HttpClient', []);    postSpy = spyOn(httpClient, 'post').and.returnValue(() => new Subject<any>().asObservable());    service = new GraphQLClientService(httpClient);  });});

Answer 1

您正在返回一个函数，该函数返回一个 Observable 而不仅仅是一个 Observable

postSpy = spyOn(httpClient, 'post').and.returnValue(new Subject<any>().asObservable());

或者

postSpy = spyOn(httpClient, 'post').and.returnValue(of({}));