File size: 2,998 Bytes
1e92f2d |
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 |
import { act, renderHook, RenderHookResult } from '@testing-library/react-hooks';
import { DependencyList } from 'react';
import { UseDebounceReturn } from '../src/useDebounce';
import { useDebounce } from '../src';
describe('useDebounce', () => {
beforeAll(() => {
jest.useFakeTimers();
});
afterEach(() => {
jest.clearAllTimers();
});
afterAll(() => {
jest.useRealTimers();
});
it('should be defined', () => {
expect(useDebounce).toBeDefined();
});
it('should return two functions', () => {
const hook = renderHook(() => useDebounce(() => {}, 5));
expect(hook.result.current.length).toBe(2);
expect(typeof hook.result.current[0]).toBe('function');
expect(typeof hook.result.current[1]).toBe('function');
});
function getHook(
ms: number = 5,
dep: DependencyList = []
): [jest.Mock, RenderHookResult<{ delay: number; deps: DependencyList }, UseDebounceReturn>] {
const spy = jest.fn();
return [
spy,
renderHook(({ delay = 5, deps = [] }) => useDebounce(spy, delay, deps), {
initialProps: {
delay: ms,
deps: dep,
},
}),
];
}
it('should call passed function after given amount of time', () => {
const [spy] = getHook();
expect(spy).not.toHaveBeenCalled();
jest.advanceTimersByTime(5);
expect(spy).toHaveBeenCalledTimes(1);
});
it('should cancel function call on unmount', () => {
const [spy, hook] = getHook();
expect(spy).not.toHaveBeenCalled();
hook.unmount();
jest.advanceTimersByTime(5);
expect(spy).not.toHaveBeenCalled();
});
it('first function should return actual state of debounce', () => {
let [, hook] = getHook();
let [isReady] = hook.result.current;
expect(isReady()).toBe(false);
hook.unmount();
expect(isReady()).toBe(null);
[, hook] = getHook();
[isReady] = hook.result.current;
jest.advanceTimersByTime(5);
expect(isReady()).toBe(true);
});
it('second function should cancel debounce', () => {
const [spy, hook] = getHook();
const [isReady, cancel] = hook.result.current;
expect(spy).not.toHaveBeenCalled();
expect(isReady()).toBe(false);
act(() => {
cancel();
});
jest.advanceTimersByTime(5);
expect(spy).not.toHaveBeenCalled();
expect(isReady()).toBe(null);
});
it('should reset timeout on delay change', () => {
const [spy, hook] = getHook(50);
expect(spy).not.toHaveBeenCalled();
hook.rerender({ delay: 5, deps: [] });
jest.advanceTimersByTime(5);
expect(spy).toHaveBeenCalledTimes(1);
});
it('should reset timeout on deps change', () => {
const [spy, hook] = getHook(50, [5, 6]);
jest.advanceTimersByTime(45);
expect(spy).not.toHaveBeenCalled();
hook.rerender({ delay: 50, deps: [6, 6] });
jest.advanceTimersByTime(45);
expect(spy).not.toHaveBeenCalled();
jest.advanceTimersByTime(5);
expect(spy).toHaveBeenCalledTimes(1);
});
});
|