Mark createStore as deprecated and add legacy_createStore

- Updated `createStore`'s doc description to mark it as `@deprecated`,
  so that it shows up with a visual strikethrough in editors.
- Added new descriptive text to `createStore` to encourage users to
  migrate to RTK, and pointing to the "RTK is Redux Today" docs page
- Rewrote TS typedefs for `createStore` to define it as a function with
  overloads, rather than a varible, to get correct docs tooltips when
  hovering over variable usages
- Added `legacy_createStore` API as an alias without the deprecation

index.d.ts

@@ -371,35 +371,135 @@ export interface StoreCreator {
   ): Store<S & StateExt, A> & Ext
 }
 
+/**
+ * @deprecated
+ *
+ * **We recommend using the `configureStore` method
+ * of the `@reduxjs/toolkit` package**, which replaces `createStore`.
+ *
+ * Redux Toolkit is our recommended approach for writing Redux logic today,
+ * including store setup, reducers, data fetching, and more.
+ *
+ * **For more details, please read this Redux docs page:**
+ * **https://redux.js.org/introduction/why-rtk-is-redux-today**
+ *
+ * `configureStore` from Redux Toolkit is an improved version of `createStore` that
+ * simplifies setup and helps avoid common bugs.
+ *
+ * You should not be using the `redux` core package by itself today, except for learning purposes.
+ * The `createStore` method from the core `redux` package will not be removed, but we encourage
+ * all users to migrate to using Redux Toolkit for all Redux code.
+ *
+ * If you want to use `createStore` without this visual deprecation warning, use
+ * the `legacy_createStore` import instead:
+ *
+ * `import { legacy_createStore as createStore} from 'redux'`
+ *
+ */
+export declare function createStore<S, A extends Action, Ext, StateExt>(
+  reducer: Reducer<S, A>,
+  enhancer?: StoreEnhancer<Ext, StateExt>
+): Store<S & StateExt, A> & Ext
+/**
+ * @deprecated
+ *
+ * **We recommend using the `configureStore` method
+ * of the `@reduxjs/toolkit` package**, which replaces `createStore`.
+ *
+ * Redux Toolkit is our recommended approach for writing Redux logic today,
+ * including store setup, reducers, data fetching, and more.
+ *
+ * **For more details, please read this Redux docs page:**
+ * **https://redux.js.org/introduction/why-rtk-is-redux-today**
+ *
+ * `configureStore` from Redux Toolkit is an improved version of `createStore` that
+ * simplifies setup and helps avoid common bugs.
+ *
+ * You should not be using the `redux` core package by itself today, except for learning purposes.
+ * The `createStore` method from the core `redux` package will not be removed, but we encourage
+ * all users to migrate to using Redux Toolkit for all Redux code.
+ *
+ * If you want to use `createStore` without this visual deprecation warning, use
+ * the `legacy_createStore` import instead:
+ *
+ * `import { legacy_createStore as createStore} from 'redux'`
+ *
+ */
+export declare function createStore<S, A extends Action, Ext, StateExt>(
+  reducer: Reducer<S, A>,
+  preloadedState?: PreloadedState<S>,
+  enhancer?: StoreEnhancer<Ext>
+): Store<S & StateExt, A> & Ext
+
 /**
  * Creates a Redux store that holds the state tree.
+ *
+ * **We recommend using `configureStore` from the
+ * `@reduxjs/toolkit` package**, which replaces `createStore`:
+ * **https://redux.js.org/introduction/why-rtk-is-redux-today**
+ *
  * The only way to change the data in the store is to call `dispatch()` on it.
  *
  * There should only be a single store in your app. To specify how different
- * parts of the state tree respond to actions, you may combine several
- * reducers
+ * parts of the state tree respond to actions, you may combine several reducers
  * into a single reducer function by using `combineReducers`.
  *
- * @template S State object type.
+ * @param {Function} reducer A function that returns the next state tree, given
+ * the current state tree and the action to handle.
  *
- * @param reducer A function that returns the next state tree, given the
- *   current state tree and the action to handle.
+ * @param {any} [preloadedState] The initial state. You may optionally specify it
+ * to hydrate the state from the server in universal apps, or to restore a
+ * previously serialized user session.
+ * If you use `combineReducers` to produce the root reducer function, this must be
+ * an object with the same shape as `combineReducers` keys.
  *
- * @param [preloadedState] The initial state. You may optionally specify it to
- *   hydrate the state from the server in universal apps, or to restore a
- *   previously serialized user session. If you use `combineReducers` to
- *   produce the root reducer function, this must be an object with the same
- *   shape as `combineReducers` keys.
+ * @param {Function} [enhancer] The store enhancer. You may optionally specify it
+ * to enhance the store with third-party capabilities such as middleware,
+ * time travel, persistence, etc. The only store enhancer that ships with Redux
+ * is `applyMiddleware()`.
+ *
+ * @returns {Store} A Redux store that lets you read the state, dispatch actions
+ * and subscribe to changes.
+ */
+export declare function legacy_createStore<S, A extends Action, Ext, StateExt>(
+  reducer: Reducer<S, A>,
+  enhancer?: StoreEnhancer<Ext, StateExt>
+): Store<S & StateExt, A> & Ext
+/**
+ * Creates a Redux store that holds the state tree.
  *
- * @param [enhancer] The store enhancer. You may optionally specify it to
- *   enhance the store with third-party capabilities such as middleware, time
- *   travel, persistence, etc. The only store enhancer that ships with Redux
- *   is `applyMiddleware()`.
+ * **We recommend using `configureStore` from the
+ * `@reduxjs/toolkit` package**, which replaces `createStore`:
+ * **https://redux.js.org/introduction/why-rtk-is-redux-today**
  *
- * @returns A Redux store that lets you read the state, dispatch actions and
- *   subscribe to changes.
+ * The only way to change the data in the store is to call `dispatch()` on it.
+ *
+ * There should only be a single store in your app. To specify how different
+ * parts of the state tree respond to actions, you may combine several reducers
+ * into a single reducer function by using `combineReducers`.
+ *
+ * @param {Function} reducer A function that returns the next state tree, given
+ * the current state tree and the action to handle.
+ *
+ * @param {any} [preloadedState] The initial state. You may optionally specify it
+ * to hydrate the state from the server in universal apps, or to restore a
+ * previously serialized user session.
+ * If you use `combineReducers` to produce the root reducer function, this must be
+ * an object with the same shape as `combineReducers` keys.
+ *
+ * @param {Function} [enhancer] The store enhancer. You may optionally specify it
+ * to enhance the store with third-party capabilities such as middleware,
+ * time travel, persistence, etc. The only store enhancer that ships with Redux
+ * is `applyMiddleware()`.
+ *
+ * @returns {Store} A Redux store that lets you read the state, dispatch actions
+ * and subscribe to changes.
  */
-export const createStore: StoreCreator
+export declare function legacy_createStore<S, A extends Action, Ext, StateExt>(
+  reducer: Reducer<S, A>,
+  preloadedState?: PreloadedState<S>,
+  enhancer?: StoreEnhancer<Ext>
+): Store<S & StateExt, A> & Ext
 
 /**
  * A store enhancer is a higher-order function that composes a store creator

src/createStore.js

@@ -5,31 +5,31 @@ import isPlainObject from './utils/isPlainObject'
 import { kindOf } from './utils/kindOf'
 
 /**
- * Creates a Redux store that holds the state tree.
- * The only way to change the data in the store is to call `dispatch()` on it.
+ * @deprecated
  *
- * There should only be a single store in your app. To specify how different
- * parts of the state tree respond to actions, you may combine several reducers
- * into a single reducer function by using `combineReducers`.
+ * **We recommend using the `configureStore` method
+ * of the `@reduxjs/toolkit` package**, which replaces `createStore`.
  *
- * @param {Function} reducer A function that returns the next state tree, given
- * the current state tree and the action to handle.
+ * Redux Toolkit is our recommended approach for writing Redux logic today,
+ * including store setup, reducers, data fetching, and more.
  *
- * @param {any} [preloadedState] The initial state. You may optionally specify it
- * to hydrate the state from the server in universal apps, or to restore a
- * previously serialized user session.
- * If you use `combineReducers` to produce the root reducer function, this must be
- * an object with the same shape as `combineReducers` keys.
+ * **For more details, please read this Redux docs page:**
+ * **https://redux.js.org/introduction/why-rtk-is-redux-today**
  *
- * @param {Function} [enhancer] The store enhancer. You may optionally specify it
- * to enhance the store with third-party capabilities such as middleware,
- * time travel, persistence, etc. The only store enhancer that ships with Redux
- * is `applyMiddleware()`.
+ * `configureStore` from Redux Toolkit is an improved version of `createStore` that
+ * simplifies setup and helps avoid common bugs.
+ *
+ * You should not be using the `redux` core package by itself today, except for learning purposes.
+ * The `createStore` method from the core `redux` package will not be removed, but we encourage
+ * all users to migrate to using Redux Toolkit for all Redux code.
+ *
+ * If you want to use `createStore` without this visual deprecation warning, use
+ * the `legacy_createStore` import instead:
+ *
+ * `import { legacy_createStore as createStore} from 'redux'`
  *
- * @returns {Store} A Redux store that lets you read the state, dispatch actions
- * and subscribe to changes.
  */
-export default function createStore(reducer, preloadedState, enhancer) {
+export function createStore(reducer, preloadedState, enhancer) {
   if (
     (typeof preloadedState === 'function' && typeof enhancer === 'function') ||
     (typeof enhancer === 'function' && typeof arguments[3] === 'function')
@@ -313,3 +313,35 @@ export default function createStore(reducer, preloadedState, enhancer) {
     [$$observable]: observable,
   }
 }
+
+/**
+ * Creates a Redux store that holds the state tree.
+ *
+ * **We recommend using `configureStore` from the
+ * `@reduxjs/toolkit` package**, which replaces `createStore`:
+ * **https://redux.js.org/introduction/why-rtk-is-redux-today**
+ *
+ * The only way to change the data in the store is to call `dispatch()` on it.
+ *
+ * There should only be a single store in your app. To specify how different
+ * parts of the state tree respond to actions, you may combine several reducers
+ * into a single reducer function by using `combineReducers`.
+ *
+ * @param {Function} reducer A function that returns the next state tree, given
+ * the current state tree and the action to handle.
+ *
+ * @param {any} [preloadedState] The initial state. You may optionally specify it
+ * to hydrate the state from the server in universal apps, or to restore a
+ * previously serialized user session.
+ * If you use `combineReducers` to produce the root reducer function, this must be
+ * an object with the same shape as `combineReducers` keys.
+ *
+ * @param {Function} [enhancer] The store enhancer. You may optionally specify it
+ * to enhance the store with third-party capabilities such as middleware,
+ * time travel, persistence, etc. The only store enhancer that ships with Redux
+ * is `applyMiddleware()`.
+ *
+ * @returns {Store} A Redux store that lets you read the state, dispatch actions
+ * and subscribe to changes.
+ */
+export const legacy_createStore = createStore

src/index.js

@@ -1,4 +1,4 @@
-import createStore from './createStore'
+import { createStore, legacy_createStore } from './createStore'
 import combineReducers from './combineReducers'
 import bindActionCreators from './bindActionCreators'
 import applyMiddleware from './applyMiddleware'
@@ -28,6 +28,7 @@ if (
 
 export {
   createStore,
+  legacy_createStore,
   combineReducers,
   bindActionCreators,
   applyMiddleware,