import { renderHook, act } from '@testing-library/react-hooks'; import Cookies from 'js-cookie'; import { useCookie } from '../src'; const setup = (cookieName: string) => renderHook(() => useCookie(cookieName)); it('should have initial value of null if no cookie exists', () => { const { result } = setup('some-cookie'); expect(result.current[0]).toBeNull(); }); it('should have initial value of the cookie if it exists', () => { const cookieName = 'some-cookie'; const value = 'some-value'; Cookies.set(cookieName, value); const { result } = setup(cookieName); expect(result.current[0]).toBe(value); // cleanup Cookies.remove(cookieName); }); it('should update the cookie on call to updateCookie', () => { const spy = jest.spyOn(Cookies, 'set'); const cookieName = 'some-cookie'; const { result } = setup(cookieName); const newValue = 'some-new-value'; act(() => { result.current[1](newValue); }); expect(result.current[0]).toBe(newValue); expect(spy).toHaveBeenCalledTimes(1); expect(spy).toHaveBeenCalledWith(cookieName, newValue, undefined); // cleanup spy.mockRestore(); Cookies.remove(cookieName); }); it('should delete the cookie on call to deleteCookie', () => { const cookieName = 'some-cookie'; const value = 'some-value'; Cookies.set(cookieName, value); const spy = jest.spyOn(Cookies, 'remove'); const { result } = setup(cookieName); expect(result.current[0]).toBe(value); act(() => { result.current[2](); }); expect(result.current[0]).toBeNull(); expect(spy).toHaveBeenCalledTimes(1); expect(spy).toHaveBeenLastCalledWith(cookieName); // cleanup spy.mockRestore(); Cookies.remove(cookieName); });