Implement renderHook

[thymikee]

Describe the Feature

See testing-library/react-testing-library#991 for details

Possible Implementations

Copy the implementation from RTL.

[MattAgn]

Hi @thymikee! I'd be glad to help on this, I'll make a PR shortly

[pierrezimmermannbam]

Hi @thymikee, @MattAgn told me he finally couldn't find time for this so I made a pr

[manugo-dev]

Hello there!

How about the waitForNextUpdate function ? Im trying to figured out how to upgrade my tests to be compatible with the new renderHook on the react-testing-library

[pierrezimmermannbam]

@manugo-dev you should be able to use react-native-testing-library's waitfor instead. If I'm correct, being able to use the async utils from the library instead of utils such as waitForNextUpdate that are a bit too focused on implementation detailswas one of the reasons why it was decided to implement a renderHook equivalent on react-native-testing-library and on react-testing-library's side

[mdjastrzebski]

Closing as implemented by #963.

[kylebake]

@manugo-dev you should be able to use react-native-testing-library's waitfor instead. If I'm correct, being able to use the async utils from the library instead of utils such as waitForNextUpdate that are a bit too focused on implementation detailswas one of the reasons why it was decided to implement a renderHook equivalent on react-native-testing-library and on react-testing-library's side

Am I correct in assuming that what you mean is there's no built in way to waitFor the return values of hooks directly anymore and we will need to always test the consumers of the hooks and have to waitFor elements to show/hide based on the values of the hook?

Edit: ignore this comment, moving discussions over to #1030

[AugustinLF]

I believe what they mean is that you can simply use waitFor to wait for the value of the hook to change. Something like that:

import {waitFor, renderHook} from '@testing-library/react-native'
import myHook from './myHook'

test('myHook', async () => {
  const {result} = renderHook(() => myHook())
  await waitFor(() => {
    expect(result.current).toBe(1)
  })
})

[kylebake]

Yes that's how the other libraries typically work with waitFor, but that's not the functionality I'm seeing with RNTL. I opened a separate issue here that I'm going to be looking more into