Mocking service calls that return observables in Angular 2?

Question

I have been trying to mock some service calls that return observables in my Angular app, but i simply can't create a valid observable that will trigger calls like catch() or map() in my code. For example:

My service:

create(): Observable<any> {
    return this.http
    .post('/api/stuff', { id: 123 })
    .catch(this.handleError)
    .map(this.extractData);
}

My spec:

let authHttpMock = mock(AuthHttp);
when(authHttpMock.post('/api/stuff', { id: 123 })).thenReturn(Observable.create(observer => {
  observer.error(new Error('500!'));
}));

const myService = new MyService(instance(authHttpMock));
myService.create({ id: 123 }).subscribe(
    result => {
    expect(result).toBeTruthy();
    }
);

The coverage analysis tells me that the handleError method has never been executed. On the case of a successful observable, it also doesn't go through the extractData method.

Where is that observable going to? How can i return a proper observable in order to test such calls?

Answer 1

Somewhere in your test code I believe you need to have this code:

AuthHttp.post('/api/stuff', {id : 123 }).subscribe(data => {});