angular2 testing using jasmine for subscribe method

Question

I have a spec code to test like this

 it(\'login test\', () => {

      const fixture = TestBed.createComponent(component);
      fixture.detectChanges();         


        

Answer 1

Change your spy for the 'login' method on your authService to return an observable instead of a value. You'll need to import:

import 'rxjs/add/observable/from';
import {Observable} from 'rxjs/Observable';

Setup your spy:

const loginResult = '';
const spy = spyOn(authService, 'login').and.callFake(() => {
    return Observable.from([loginResult]);
})

Call login:

fixture.componentInstance.login();

Assert:

expect(spy).toHaveBeenCalled();