fix(core): retry for infinite queries (issue #8046) (#8049)

* Add reproduction test for infinite loop retries (issue #8046)

* ci: apply automated fixes

* fix: retry for infinite queries

The retryer lives above the fetchFn, and it re-runs the fetchFn whenever a retry happens. Usually, the fetchFn is a thin wrapper around the actual queryFn passed by the user. However, for infinite queries, it fetches all pages in a loop.
The retryer breaks out of this loop if an error occurs on e.g. the second page, and then retries by running the fetchFn - which will re-set the loop

This fix hoists the currentPage counter out of the fetchFn - into the closure created by onFetch. The outer closure is created from running `query.fetch` once, so it won't be re-set between retries.
The fix also re-writes the fetch loop to always take the `currentPage` into account, where it was previously treating the first page differently

---------

Co-authored-by: autofix-ci[bot] <114827586+autofix-ci[bot]@users.noreply.github.com>
Co-authored-by: Dominik Dorfmeister <office@dorfmeister.cc>

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

@@ -2,7 +2,12 @@ import { afterEach, beforeEach, describe, expect, test, vi } from 'vitest'
 import { waitFor } from '@testing-library/react'
 import { CancelledError, InfiniteQueryObserver } from '..'
 import { createQueryClient, queryKey, sleep } from './utils'
-import type { InfiniteQueryObserverResult, QueryCache, QueryClient } from '..'
+import type {
+  InfiniteData,
+  InfiniteQueryObserverResult,
+  QueryCache,
+  QueryClient,
+} from '..'
 
 describe('InfiniteQueryBehavior', () => {
   let queryClient: QueryClient
@@ -323,4 +328,72 @@ describe('InfiniteQueryBehavior', () => {
 
     unsubscribe()
   })
+
+  test('InfiniteQueryBehavior should not enter an infinite loop when a page errors while retry is on #8046', async () => {
+    let errorCount = 0
+    const key = queryKey()
+
+    interface TestResponse {
+      data: Array<{ id: string }>
+      nextToken?: number
+    }
+
+    const fakeData = [
+      { data: [{ id: 'item-1' }], nextToken: 1 },
+      { data: [{ id: 'item-2' }], nextToken: 2 },
+      { data: [{ id: 'item-3' }], nextToken: 3 },
+      { data: [{ id: 'item-4' }] },
+    ]
+
+    const fetchData = async ({ nextToken = 0 }: { nextToken?: number }) =>
+      new Promise<TestResponse>((resolve, reject) => {
+        setTimeout(() => {
+          if (nextToken == 2 && errorCount < 3) {
+            errorCount += 1
+            reject({ statusCode: 429 })
+            return
+          }
+          resolve(fakeData[nextToken] as TestResponse)
+        }, 10)
+      })
+
+    const observer = new InfiniteQueryObserver<
+      TestResponse,
+      Error,
+      InfiniteData<TestResponse>,
+      TestResponse,
+      typeof key,
+      number
+    >(queryClient, {
+      retry: 5,
+      staleTime: 0,
+      retryDelay: 10,
+
+      queryKey: key,
+      initialPageParam: 1,
+      getNextPageParam: (lastPage) => lastPage.nextToken,
+      queryFn: ({ pageParam }) => fetchData({ nextToken: pageParam }),
+    })
+
+    // Fetch Page 1
+    const page1Data = await observer.fetchNextPage()
+    expect(page1Data.data?.pageParams).toEqual([1])
+
+    // Fetch Page 2, as per the queryFn, this will reject 2 times then resolves
+    const page2Data = await observer.fetchNextPage()
+    expect(page2Data.data?.pageParams).toEqual([1, 2])
+
+    // Fetch Page 3
+    const page3Data = await observer.fetchNextPage()
+    expect(page3Data.data?.pageParams).toEqual([1, 2, 3])
+
+    // Now the real deal; re-fetching this query **should not** stamp into an
+    // infinite loop where the retryer every time restarts from page 1
+    // once it reaches the page where it errors.
+    // For this to work, we'd need to reset the error count so we actually retry
+    errorCount = 0
+    const reFetchedData = await observer.refetch()
+
+    expect(reFetchedData.data?.pageParams).toEqual([1, 2, 3])
+  })
 })

packages/query-core/src/infiniteQueryBehavior.ts

@@ -13,14 +13,15 @@ export function infiniteQueryBehavior<TQueryFnData, TError, TData, TPageParam>(
 ): QueryBehavior<TQueryFnData, TError, InfiniteData<TData, TPageParam>> {
   return {
     onFetch: (context, query) => {
+      const options = context.options as InfiniteQueryPageParamsOptions<TData>
+      const direction = context.fetchOptions?.meta?.fetchMore?.direction
+      const oldPages = context.state.data?.pages || []
+      const oldPageParams = context.state.data?.pageParams || []
+      let result: InfiniteData<unknown> = { pages: [], pageParams: [] }
+      let currentPage = 0
+
       const fetchFn = async () => {
-        const options = context.options as InfiniteQueryPageParamsOptions<TData>
-        const direction = context.fetchOptions?.meta?.fetchMore?.direction
-        const oldPages = context.state.data?.pages || []
-        const oldPageParams = context.state.data?.pageParams || []
-        const empty = { pages: [], pageParams: [] }
         let cancelled = false
-
         const addSignalProperty = (object: unknown) => {
           Object.defineProperty(object, 'signal', {
             enumerable: true,
@@ -78,8 +79,6 @@ export function infiniteQueryBehavior<TQueryFnData, TError, TData, TPageParam>(
           }
         }
 
-        let result: InfiniteData<unknown>
-
         // fetch next / previous page?
         if (direction && oldPages.length) {
           const previous = direction === 'backward'
@@ -92,22 +91,20 @@ export function infiniteQueryBehavior<TQueryFnData, TError, TData, TPageParam>(
 
           result = await fetchPage(oldData, param, previous)
         } else {
-          // Fetch first page
-          result = await fetchPage(
-            empty,
-            oldPageParams[0] ?? options.initialPageParam,
-          )
-
           const remainingPages = pages ?? oldPages.length
 
-          // Fetch remaining pages
-          for (let i = 1; i < remainingPages; i++) {
-            const param = getNextPageParam(options, result)
+          // Fetch all pages
+          do {
+            const param =
+              currentPage === 0
+                ? (oldPageParams[0] ?? options.initialPageParam)
+                : getNextPageParam(options, result)
             if (param == null) {
               break
             }
             result = await fetchPage(result, param)
-          }
+            currentPage++
+          } while (currentPage < remainingPages)
         }
 
         return result