fix(query): gracefully handle CancelledError

[aulneau]

So this was a strange bug that I came upon. It would happen where I had an atomWithInfiniteQuery already loaded, and then navigated to a page that had that same query. It seems there is some default cancellation behavior in the way infiniteQueries work in react query.

I think this solution makes sense, and it fixes my bug (without this, the application breaks).

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[dai-shi]

I wasn't aware about the cancellation of promise. I think it's better if we can simply ignore it.
Is it the issue with atomWithQuery too?

[dai-shi]

Suggested change

	if (prevData) settlePromise(prevData)
	settlePromise = null
	if (prevData) {
	settlePromise(prevData)
	settlePromise = null
	}

settlePromise should be cleared only if it's invoked.

[dai-shi]

resolving with prevData is required for refetch? hm but this file is atomWithInfiniteQuery, not atomWithQuery.
I feel this a bit weird because settlePromise and setData are always paired.

Can we do

        if (result.error && !isCancelledError(result.error)) {

in L91?

[aulneau]

Yep that works too, wasn't sure if we needed to do the settledPromise stuff (tbh not clear on what it does exactly lol)

[dai-shi]

I know. This is because of very tricky suspense behavior. I'm not even 100% sure, so adding tests to check the behavior would be important.

[aulneau]

Is it the issue with atomWithQuery too?

I have not run into it, and looking at the source code of react query, it seems that there isn't this same kind of CancelledError usage in a non-infinite query.

[dai-shi]

Cool. This looks just fine.