fix(react-query): Allow optional initialData in infiniteQueryOptions (#8154)

* fix(react-query): Allow optional initialData in infiniteQueryoptions

* fixup! fix(react-query): Allow optional initialData in infiniteQueryoptions

---------

Co-authored-by: chosunghoon <shcho@team-everywhere.com>
Co-authored-by: Dominik Dorfmeister <office@dorfmeister.cc>

Author: 3 people

packages/react-query/src/__tests__/infiniteQueryOptions.test-d.tsx

@@ -4,7 +4,7 @@ import { infiniteQueryOptions } from '../infiniteQueryOptions'
 import { useInfiniteQuery } from '../useInfiniteQuery'
 import { useSuspenseInfiniteQuery } from '../useSuspenseInfiniteQuery'
 import { useQuery } from '../useQuery'
-import type { InfiniteData } from '@tanstack/query-core'
+import type { InfiniteData, InitialDataFunction } from '@tanstack/query-core'
 
 describe('queryOptions', () => {
   it('should not allow excess properties', () => {
@@ -152,4 +152,23 @@ describe('queryOptions', () => {
     // @ts-expect-error cannot pass infinite options to non-infinite query functions
     queryClient.prefetchQuery(options)
   })
+
+  test('allow optional initialData', () => {
+    const initialData: { example: boolean } | undefined = { example: true }
+    const queryOptions = infiniteQueryOptions({
+      queryKey: ['example'],
+      queryFn: async () => initialData,
+      // initialData below errors
+      initialData: initialData
+        ? () => ({ pages: [initialData], pageParams: [] })
+        : undefined,
+      getNextPageParam: () => 1,
+      initialPageParam: 1,
+    })
+    queryOptions.initialData
+    expectTypeOf(queryOptions.initialData).toMatchTypeOf<
+      | InitialDataFunction<InfiniteData<{ example: boolean }, number>>
+      | undefined
+    >()
+  })
 })

packages/react-query/src/infiniteQueryOptions.ts

@@ -2,6 +2,7 @@ import type {
   DataTag,
   DefaultError,
   InfiniteData,
+  InitialDataFunction,
   QueryKey,
 } from '@tanstack/query-core'
 import type { UseInfiniteQueryOptions } from './types'
@@ -20,7 +21,11 @@ export type UndefinedInitialDataInfiniteOptions<
   TQueryKey,
   TPageParam
 > & {
-  initialData?: undefined
+  initialData?:
+    | undefined
+    | InitialDataFunction<
+        NonUndefinedGuard<InfiniteData<TQueryFnData, TPageParam>>
+      >
 }
 
 type NonUndefinedGuard<T> = T extends undefined ? never : T