Check if a function has been called, Angular unit testing

Question

I have called a function inside ngOnInit,

ngOnInit() {
 this.isSubscribable();
}

I wan to do unit testing for this ngOnInit like this:

    it('Check isSubscribable is called from ngOnInit', async(async() => {
      spyOn(component, 'isSubscribable').and.callThrough();
      fixture.detectChanges();
      await fixture.whenStable();
      expect(component.isSubscribable).toHaveBeenCalled();

    }))

This is not working. I need some help on this.

Answer 1

What if you try like this ?

it('Check isSubscribable is called from ngOnInit', () => {
  const spySubscribable = spyOn(component, 'isSubscribable');
  component.ngOnInit();
  expect(spySubscribable).toHaveBeenCalled();
});