服务器停止或玩笑测试结束时如何处理setTimeout

Question

I have a timeout that on api request POST /api/exchange-refresh-token run's a query to remove used refresh token with a delay (delay is required to allow multiple exchanges in small timeframe). While running jest tests I got an error Jest did not exit one second after the test run has completed because of this setTimeout

setTimeout(() => { removeRefreshToken(id).catch(err=>log(err)) }, 5000)

That issue forced me to think, what should I do with this setTimeout to run it without delay on server stop or jest test end (or to skip it)? What is a proper way to take care of timers in this cases?

Answer 1

You can use jest.useFakeTimers() to fake a timeout like this:

timerGame.js

function timerGame(callback) {
  console.log('Ready....go!');
  setTimeout(() => {
    console.log("Time's up -- stop!");
    callback && callback();
  }, 1000);
}

module.exports = timerGame;

tests /timerGame-test.js

jest.useFakeTimers();
jest.spyOn(global, 'setTimeout');

test('waits 1 second before ending the game', () => {
  const timerGame = require('../timerGame');
  timerGame();

  expect(setTimeout).toHaveBeenCalledTimes(1);
  expect(setTimeout).toHaveBeenLastCalledWith(expect.any(Function), 1000);
});

Have many way to fake a timeout for jet, you can see in here: https://jestjs.io/docs/timer-mocks