NgRx effects test

books.effects.spec.ts

describe('getBooks action', function () {
  it("should call getBooks and redirect to booksLoaded action", (done) => {
    spyOn(booksService, "getBooks").and.returnValue(of(books))
    actions$ = of(BookStoreActions.loadBooks);
    effects.loadBooks$.subscribe(res => {
      expect(booksService.getBooks).toHaveBeenCalled()
      expect(res).toEqual(BookStoreActions.booksLoaded({books: books}))
      done()
    })
  })
});