import { renderHook } from '@testing-library/react-hooks'; import { useFirstMountState } from '../src'; describe('useFirstMountState', () => { it('should be defined', () => { expect(useFirstMountState).toBeDefined(); }); it('should return boolean', () => { expect(renderHook(() => useFirstMountState()).result.current).toEqual(expect.any(Boolean)); }); it('should return true on first render and false on all others', () => { const hook = renderHook(() => useFirstMountState()); expect(hook.result.current).toBe(true); hook.rerender(); expect(hook.result.current).toBe(false); hook.rerender(); expect(hook.result.current).toBe(false); }); });