feat(query-core): add retryAttempt to query error callback context

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

@@ -325,12 +325,36 @@ describe('queryCache', () => {
       })
       await vi.advanceTimersByTimeAsync(100)
       const query = testCache.find({ queryKey: key })
-      expect(onError).toHaveBeenCalledWith('error', query)
+      expect(onError).toHaveBeenCalledWith('error', query, {
+        retryAttempt: 0,
+      })
       expect(onError).toHaveBeenCalledTimes(1)
       expect(onSuccess).not.toHaveBeenCalled()
       expect(onSettled).toHaveBeenCalledTimes(1)
       expect(onSettled).toHaveBeenCalledWith(undefined, 'error', query)
     })
+
+    it('should include retryAttempt in the onError context', async () => {
+      const key = queryKey()
+      const onError = vi.fn()
+      const testCache = new QueryCache({ onError })
+      const testClient = new QueryClient({ queryCache: testCache })
+
+      testClient.prefetchQuery({
+        queryKey: key,
+        queryFn: () => sleep(0).then(() => Promise.reject('error')),
+        retry: 2,
+        retryDelay: 0,
+      })
+
+      await vi.advanceTimersByTimeAsync(10)
+
+      const query = testCache.find({ queryKey: key })
+      expect(onError).toHaveBeenCalledTimes(1)
+      expect(onError).toHaveBeenCalledWith('error', query, {
+        retryAttempt: 2,
+      })
+    })
   })
 
   describe('QueryCacheConfig success callbacks', () => {

packages/query-core/src/query.ts

@@ -533,6 +533,7 @@ export class Query<
     }
 
     // Try to fetch the data
+    let latestFailureRetryCount = 0
     this.#retryer = createRetryer({
       initialPromise: fetchOptions?.initialPromise as
         | Promise<TData>
@@ -548,6 +549,7 @@ export class Query<
         abortController.abort()
       },
       onFail: (failureCount, error) => {
+        latestFailureRetryCount = failureCount
         this.#dispatch({ type: 'failed', failureCount, error })
       },
       onPause: () => {
@@ -610,6 +612,7 @@ export class Query<
       this.#cache.config.onError?.(
         error as any,
         this as Query<any, any, any, any>,
+        { retryAttempt: latestFailureRetryCount },
       )
       this.#cache.config.onSettled?.(
         this.state.data,

packages/query-core/src/queryCache.ts

@@ -20,6 +20,9 @@ interface QueryCacheConfig {
   onError?: (
     error: DefaultError,
     query: Query<unknown, unknown, unknown>,
+    context: {
+      retryAttempt: number
+    },
   ) => void
   onSuccess?: (data: unknown, query: Query<unknown, unknown, unknown>) => void
   onSettled?: (