Angular2 测试异步 Http.MockBackend.connections 承诺不屈服

Question

我在使用 injectAsync 和 http.MockBackend 时遇到问题。 auth.ngOnInit() 方法调用 Http.get()，但在本次测试中从未调用 MockBackend.connections.toPromise().then() 方法：

it('should check if the user is authenticated',
   injectAsync([Auth, MockBackend], (auth, backend) => {
     let promise = backend.connections.toPromise().then(
       (connection) => {
         let link = document.createElement('a');
         link.href = connection.request.url;
         expect(link.pathname).toBe('/api/auth/user/');
       });
     auth.ngOnInit();
     return promise;
}));

我已经在调试器中确认正在调用 MockBackend.connections.next() 方法。然而，当我运行测试时，它失败了 Error: Timeout - Async callback was not invoked within timeout specified by jasmine.DEFAULT_TIMEOUT_INTERVAL. 我在这里错过了什么？

Answer 1

感谢@alxhub 和@ericmartinezr in gitter，问题是我需要在调用 toPromise() 之前将可观察范围缩小到单个结果。所以这有效：

it('should check if the user is authenticated',
   injectAsync([Auth, MockBackend], (auth, backend) => {
     let promise = backend.connections.first().toPromise().then(
       (connection) => {
         let link = document.createElement('a');
         link.href = connection.request.url;
         expect(link.pathname).toBe('/api/auth/user/');
       });
     auth.ngOnInit();
     return promise;
}));

Angular2 测试异步 Http.MockBackend.connections 承诺不屈服

Angular2 test async Http.MockBackend.connections promise not yielding

javascript

promise

observable

jasmine

angularjs