`useInfiniteQuery` sends page param with value `0` on first page when `initialPageParam` is `undefined`

[sbalay]

openapi-react-query version

0.5.4

Description

Bug

When calling useInfiniteQuery with initialPageParam: undefined, the first page request still includes the page parameter in the query string with value 0.

Root cause

In the queryFn implementation, pageParam defaults to 0:

queryFn: async ({ pageParam = 0, signal }) => {
  query: {
    [pageParamName]: pageParam, // sends e.g. after=0 on first page
  }
}

When initialPageParam is undefined, pageParam is undefined, which the destructuring default then replaces with 0. The page param is then always included in the query — even for the first page.

Expected behavior

When pageParam is undefined (i.e. the initial page), the page param should be omitted from the query entirely.

Suggested fix

queryFn: async ({ pageParam, signal }) => {
  query: {
    ...(pageParam !== undefined ? { [pageParamName]: pageParam } : {}),
  }
}

Impact

APIs that use cursor-based pagination receive an unexpected cursor=0 (or equivalent) on the first request, which they may not handle gracefully — since 0 is not a valid cursor value.

Reproduction

Craft an infinite query and set the initialPageParam as undefined. See that the request includes the page param as 0

Expected result

When pageParam is undefined (i.e. the initial page), the page param should be omitted from the query entirely.

Extra

• I’m willing to open a PR (see CONTRIBUTING.md)