fix(query-core): refetch cached infinite query pages without getNextPageParam 🤖🤖🤖

.changeset/tidy-pages-refetch.md

@@ -0,0 +1,5 @@
+---
+'@tanstack/query-core': patch
+---
+
+Reuse cached `pageParams` when refetching an infinite query that has no `getNextPageParam`, instead of throwing `TypeError: options.getNextPageParam is not a function`.

packages/query-core/src/__tests__/infiniteQueryObserver.test.tsx

@@ -174,6 +174,24 @@ describe('InfiniteQueryObserver', () => {
     expect(observer.getCurrentResult().hasNextPage).toBe(false)
   })
 
+  it('should report no next page when getNextPageParam is not provided', () => {
+    const key = createKey()
+
+    queryClient.setQueryData(key, {
+      pages: ['page 0', 'page 1'],
+      pageParams: [0, 1],
+    })
+
+    // @ts-expect-error getNextPageParam is optional when no pages are requested
+    const observer = new InfiniteQueryObserver(queryClient, {
+      queryKey: key,
+      queryFn: () => sleep(10).then(() => 'page'),
+      initialPageParam: 0,
+    })
+
+    expect(observer.getCurrentResult().hasNextPage).toBe(false)
+  })
+
   it('should stop refetching if null is returned from getNextPageParam', async () => {
     const key = createKey()
     let next: number | null = 2

packages/query-core/src/__tests__/queryClient.test.tsx

@@ -1685,6 +1685,36 @@ describe('queryClient', () => {
       })
       expect(result).toStrictEqual([20])
     })
+
+    it('should refetch all cached pages using their pageParams when getNextPageParam is not provided', async () => {
+      const key = createKey()
+
+      queryClient.setQueryData(key, {
+        pages: ['cached page 0', 'cached page 1'],
+        pageParams: [0, 1],
+      })
+
+      const queryFn = vi.fn<
+        (context: { pageParam: number }) => Promise<string>
+      >(({ pageParam }: { pageParam: number }) =>
+        Promise.resolve(`page ${String(pageParam)}`),
+      )
+
+      const result = await queryClient.infiniteQuery({
+        queryKey: key,
+        queryFn,
+        initialPageParam: 0,
+      })
+
+      expect(result).toStrictEqual({
+        pages: ['page 0', 'page 1'],
+        pageParams: [0, 1],
+      })
+      expect(queryFn).toHaveBeenCalledTimes(2)
+      expect(
+        queryFn.mock.calls.map(([context]) => context.pageParam),
+      ).toStrictEqual([0, 1])
+    })
   })
 
   /** @deprecated */
@@ -1779,6 +1809,35 @@ describe('queryClient', () => {
       // this check ensures we're exiting the fetch loop early
       expect(count).toBe(3)
     })
+
+    it('should refetch cached pages using their pageParams when getNextPageParam is not provided', async () => {
+      const key = createKey()
+
+      queryClient.setQueryData(key, {
+        pages: ['cached page 0', 'cached page 1'],
+        pageParams: [0, 1],
+      })
+
+      const queryFn = vi.fn<
+        (context: { pageParam: number }) => Promise<string>
+      >(({ pageParam }: { pageParam: number }) =>
+        Promise.resolve(`page ${String(pageParam)}`),
+      )
+
+      // oxlint-disable-next-line tanstack-query/no-restricted-syntax -- grandfathered direct test
+      await queryClient.prefetchInfiniteQuery({
+        queryKey: key,
+        queryFn,
+        initialPageParam: 0,
+      })
+
+      expect(queryClient.getQueryState(key)?.status).toBe('success')
+      expect(queryClient.getQueryData(key)).toStrictEqual({
+        pages: ['page 0', 'page 1'],
+        pageParams: [0, 1],
+      })
+      expect(queryFn).toHaveBeenCalledTimes(2)
+    })
   })
 
   describe('infiniteQuery used for prefetching', () => {

packages/query-core/src/infiniteQueryBehavior.ts

@@ -112,7 +112,9 @@ export function infiniteQueryBehavior<TQueryFnData, TError, TData, TPageParam>(
                 ? oldPageParams[0] === undefined
                   ? options.initialPageParam
                   : oldPageParams[0]
-                : getNextPageParam(options, result)
+                : typeof options.getNextPageParam === 'function'
+                  ? getNextPageParam(options, result)
+                  : oldPageParams[currentPage]
             if (currentPage > 0 && param == null) {
               break
             }
@@ -191,7 +193,7 @@ export function hasNextPage(
   options: InfiniteQueryPageParamsOptions<any, any>,
   data?: InfiniteData<unknown>,
 ): boolean {
-  if (!data) return false
+  if (!data || !options.getNextPageParam) return false
   return getNextPageParam(options, data) != null
 }