gist for medium

interval.test.js

it('someMethod would be ran with iterator each second', fakeAsync(() => {
    myService.someMethod();

    tick(2 * 1000);

    expect(logger.logObservable).toHaveBeenCalledTimes(2);
    expect(logger.logInterval).toHaveBeenCalledTimes(1);

    // tell jasmine we don't need to emulate async anymore in this case
    discardPeriodicTasks();
}));