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内容：测试返回依赖于嵌套 http 调用的 Promise 的异步函数

有：Angular 9，茉莉花 3.4.0

问题：错误：超时 - 异步回调未在 5000 毫秒内调用（由 jasmine.DEFAULT_TIMEOUT_INTERVAL 设置）错误：预期没有打开请求，发现 1：GET http://localhost:9876/24a27be6-9f62-4156-8fd4-adcd945ec909

import ...

export interface UserData {...}

@Injectable()
export class UserDataManagementService {
  private userID: string | undefined;
  public userData: UserData;

  constructor(...) {}

  private async loadUserData() {
    const headers = await this.getHeaders();
    return this.httpClient
      .get<UserData>(window.location.origin + '/' + this.userID, { headers })
      .toPromise()
      .then((data) => {
         this.userData = data;
      })
      .catch((e) => {
        this.logger.error('Error in loadUserData: ', e);
      });
  }

  private async getHeaders() {...}
}

这是我的测试：

import ...
const mockUserData: UserData = {...};

describe('UserDataManagementService', () => {
  let httpTestingController: HttpTestingController;
  let service: UserDataManagementService;
  beforeEach(() => {
    TestBed.configureTestingModule({
      imports: [HttpClientTestingModule],
      providers: [
        UserDataManagementService,
        ...
      ],
    });
    httpTestingController = TestBed.get(HttpTestingController);
    service = TestBed.get(UserDataManagementService);
 });

  afterEach(() => {
    httpTestingController.verify();
  });


describe('loadUserData', () => {
    it('should return user data on success', (done) => {
      (service as any).userID = '24a27be6-9f62-4156-8fd4-adcd945ec909';
      (service as any).loadUserData().then(() => {
        expect((service as any).userData).toEqual(mockUserData);
        const req = httpTestingController.expectOne( 
          'http://localhost:9876/24a27be6-9f62-4156-8fd4-adcd945ec909',
        );
        expect(req.request.method).toEqual('GET');
        req.flush(mockUserData);
        done();
      });
    });
  });
});

到目前为止我尝试了什么：

  • 试图将默认超时时间增加到 20000 毫秒 -没有用
  • done / async / await 等的不同组合。
  • 在 then() 之外放置 httpTestingController.expectOne （实际上没有意义，但我已经尝试了一切）
  • 如果我将 httpTestingController.verify() 放入此测试，则错误“预期没有打开的请求...”消失

这不是以下内容的重复：

  • 我的函数返回一个承诺，就像这里
  • 我使用 done()，就像这里
  • 我没有像这里这样的长期任务
  • fakeAsync 对我也没有帮助......
4

1 回答 1

1

虽然我无法重现您的测试环境，但您的测试似乎正在超时，因为您的模拟请求从未得到满足。它从未实现的原因是因为您在旨在处理响应的回调中刷新了测试请求。

(service as any).loadUserData().then(() => {
        const req = httpTestingController.expectOne(
          'http://localhost:9876/24a27be6-9f62-4156-8fd4-adcd945ec909',
        );
        expect((service as any).userData).toEqual(mockUserData);
        expect(getHeadersSpy).toHaveBeenCalled();
        expect(req.request.method).toEqual('GET');
        // this line tells the test scaffolding to fulfill the request
        req.flush(mockUserData); 
        done();
      });

我希望如果您重构以刷新请求，那么您的测试将不会超时（可能仍因其他原因而失败）。

const req = httpTestingController.expectOne('http://localhost:9876/24a27be6-9f62-4156-8fd4-adcd945ec909');
(service as any).loadUserData().then(() => {
    expect((service as any).userData).toEqual(mockUserData);
    expect(getHeadersSpy).toHaveBeenCalled();
    expect(req.request.method).toEqual('GET');
    done();
});

req.flush(mockUserData); // <= essentially: 'call my callback now!'
于 2020-05-19T19:15:28.483 回答