Merge pull request #3948 from reduxjs/extractrehydrationinfo-circular

Author: markerikson

docs/rtk-query/usage/persistence-and-rehydration.mdx

@@ -37,28 +37,33 @@ box with the `autoMergeLevel1` or `autoMergeLevel2` [state reconcilers](https://
 when persisting the root reducer, or with the `autoMergeLevel1` reconciler when persisting just the api reducer.
 
 ```ts title="redux-persist rehydration example"
-import type { Action, PayloadAction } from '@reduxjs/toolkit'
+import type { Action } from '@reduxjs/toolkit'
 import { createApi, fetchBaseQuery } from '@reduxjs/toolkit/query/react'
 import { REHYDRATE } from 'redux-persist'
 
 type RootState = any // normally inferred from state
 
-function isHydrateAction(action: Action): action is PayloadAction<RootState> {
+function isHydrateAction(action: Action): action is Action<typeof REHYDRATE> & {
+  key: string
+  payload: RootState
+  err: unknown
+} {
   return action.type === REHYDRATE
 }
 
 export const api = createApi({
   baseQuery: fetchBaseQuery({ baseUrl: '/' }),
   // highlight-start
-  extractRehydrationInfo(action, { reducerPath }) {
+  // to prevent circular type issues, the return type needs to be annotated as any
+  extractRehydrationInfo(action, { reducerPath }): any {
     if (isHydrateAction(action)) {
-      if ((action as any).key === 'key used with redux-persist') {
-        // when persisting the api reducer
+      // when persisting the api reducer
+      if (action.key === 'key used with redux-persist') {
         return action.payload
       }
 
       // When persisting the root reducer
-      return action.payload[reducerPath]
+      return action.payload[api.reducerPath]
     }
   },
   // highlight-end

packages/toolkit/src/query/createApi.ts

@@ -182,7 +182,7 @@ export interface CreateApiOptions<
    * export const api = createApi({
    *   baseQuery: fetchBaseQuery({ baseUrl: '/' }),
    *   // highlight-start
-   *   extractRehydrationInfo(action, { reducerPath }) {
+   *   extractRehydrationInfo(action, { reducerPath }): any {
    *     if (isHydrateAction(action)) {
    *       return action.payload[reducerPath]
    *     }