Cannot read property 'subscribe' of undefined after running npm test (Angular 2 unit testing)
Assuming you have a service that has a method that returns an observable, say
class SomeService { getData(): Observable<Data> {}}You could....
Create a spy1 where you return an object with a noop subscribe function.
let mockSomeService = { getData: () => {}}TestBed.configureTestingModule({ providers: [ { provide: SomeService, useValue: mockSomeService } ]})it('...', () => { spyOn(mockSomeService, 'getData').and.returnValue({ subscribe: () => {} }) // do stuff expect(mockSomService.getData).toHaveBeenCalled();})You could...
Return an actual observable in the spy
spyOn(mockSomeService, 'getData').and.returnValue(Observable.of(someData))Maybe this will be preferred over the noop subscribe method, because if the call on the service is changing something in the component, this is something you probably will want to test
You could...
Do something like in this post.