pages in the getNextPageParam method in infiniteQueryBehavior is undefined. about query HOT 3 CLOSED

we only call the getNextPageParam function after we've already successfully fetched at least one page, so the access you're showing is safe. Also, we have tests for this.

the place your stacktrace points to comes likely from here:

so I think you wind up with corrupted data in your cache, e.g. an empty array that doesn't conform to the InfiniteData type structure. This should be trivial to debug by looking into the query devtools or by setting a logpoint / breakpoint at the location where the error occurs.

one wild guess is that you call setQueryData on this entry, or have a global intitialData that gets applied and puts the wrong structure in the cache. This is as far as my guesswork goes without seeing a proper reproduction. If you file another issue about this without showing a reproduction, I will close it without comment.

from query.

I have this problem today. It occured because the queryKey is the same as another query ( not an infinite one)

from query.

keys need to be unique, see: https://tkdodo.eu/blog/effective-react-query-keys#caching-data

from query.