Never rejects if Date.now is mocked in the test

[valignatev]

Hi there, thanks for a nice and convenient package!

This is mostly the same case as #4, but Date.now is mocked instead of setTimeout. And if the Date.now is mocked, this condition: https://github.com/TheBrainFamily/wait-for-expect/blob/master/src/index.ts#L21 will be either always true, or always false. So tests with mocked Date.now will either fail without retrying, or fail with temeout error.

The solution for this is always to use the real Date.now the same way we're doing with setTimeout. I'll provide a PR for this where we can continue the discussion.

[valignatev]

Bonus: example of such mock in the real world: https://github.com/facebook/jest/blob/6d3da9be06350bfa7414b609807ebd0cbdf0c416/examples/snapshot/__tests__/clock.react.test.js#L11

[lgandecki]

Merged and released, thank you so much :-)

[chetmurphy]

I am using typescript with react-hooks-testing-library that uses this library. To get tests to run, I had to mock Date in my tests

declare global {
  interface Window { Date: any; }
}
window.Date = Date;

And comment out the code in wait-for-expect starting at line 16:

var _ref = typeof window !== "undefined" ? window : global,
   setTimeout = _ref.setTimeout,
   now = _ref.Date.now;

Is this a bug?

[lgandecki]

Could you please make a small reproduction that shows the problem?

[chetmurphy]

Repro at https://github.com/chetmurphy/wait-for-expect-test After installing with yarn run yarn test – will fail ● Test suite failed to run TypeError: Cannot read property 'now' of undefined at Object.<anonymous> (node_modules/wait-for-expect/lib/index.js:16:21) at Object.<anonymous> (node_modules/dom-testing-library/dist/wait.js:10:45) at Object.<anonymous> (node_modules/dom-testing-library/dist/index.js:83:13) Test Suites: 1 failed, 1 total Comment out wait for expect section at wait-for-expect/lib/index.js:16 Rerun yarn test - should succeed.

…

--Chet

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