Bug in useMemo (?) about fre HOT 6 CLOSED

Looks good now, thanks!

from fre.

This seems to be a bug. The code here is not very clear. Maybe I need to refactor it.

from fre.

@mindplay-dk I refactored useMemo just now, and now it might work.

from fre.

Same problem as before, but it's not useMemo causing it anymore. 🤔

It could have something to do with the combination of useState and useEffect maybe?

I've been trying to write a test - it should be simple really:

test('useEffect with change detection', async () => {
  let updates = 0

  let effect = () => updates += 1

  const Component = ({ value }) => {
    useEffect(effect, [value])

    return <div>foo</div>
  }

  await testUpdates([
    { content: <Component value={1}/>, test: () => expect(updates).toBe(1) }, // mounted: should trigger effect
    { content: <Component value={2}/>, test: () => expect(updates).toBe(2) }, // updated: should trigger effect
    { content: <Component value={2}/>, test: () => expect(updates).toBe(2) }, // no change: should NOT trigger effect
  ])
})

For some reason, the test just runs forever, and jest doesn't time out like it should... I have no idea how to fix this. 😐

from fre.

I seem to know what you mean. Maybe my understanding of useEffect is biased.
Can you send me the url of sandbox? I need to debug the use case. Thank you very much.

from fre.

https://codesandbox.io/s/fre-demo-uxuic

from fre.