From e87d156eb1b3715b453072798cbb38d4413adc99 Mon Sep 17 00:00:00 2001
From: Dominik Dorfmeister <office@dorfmeister.cc>
Date: Sun, 30 Apr 2023 18:35:50 +0200
Subject: [PATCH] chore: remove createStore option

having the option to customize the internal store sound nice, but the problem is that the store holds Query instances, not data. So, the setter is only called once, not on every data update. This makes it relatively useless - every time we thought we could leverage createStore, it fell short of our requirements because of this.

The better way is usually to subscribe to the QueryCache directly
---
 docs/react/guides/migrating-to-v5.md            | 12 ------------
 docs/react/reference/QueryCache.md              |  3 ---
 packages/query-core/src/queryCache.ts           |  3 +--
 .../query-core/src/tests/queryCache.test.tsx    | 17 -----------------
 4 files changed, 1 insertion(+), 34 deletions(-)

diff --git a/docs/react/guides/migrating-to-v5.md b/docs/react/guides/migrating-to-v5.md
index 7a51885c13..0d674791a7 100644
--- a/docs/react/guides/migrating-to-v5.md
+++ b/docs/react/guides/migrating-to-v5.md
@@ -443,16 +443,4 @@ Note that the infinite list must be bi-directional, which requires both `getNext
 
 See the [Typescript Docs](../typescript#typing-query-options) for more details.
 
-### CreateStore
-
-We are now exposing a way to customize how queries are stored internally. Per default, a `Map` is used but, with the new `createStore` function, you can now use any data structure you want.
-
-```ts
-const queryClient = new QueryClient({
-  queryCache: new QueryCache({
-    createStore: () => new Map()
-  }),
-})
-```
-
 [//]: # 'NewFeatures'
diff --git a/docs/react/reference/QueryCache.md b/docs/react/reference/QueryCache.md
index b19e31f774..16a0434345 100644
--- a/docs/react/reference/QueryCache.md
+++ b/docs/react/reference/QueryCache.md
@@ -43,9 +43,6 @@ Its available methods are:
 - `onSettled?:` (data: unknown | undefined, error: unknown | null, query: Query) => void
   - Optional
   - This function will be called if some query is settled (either successful or errored).
-- `createStore?: () => QueryStore`
-  - Optional
-  - This function will be called to create the store that will be used to store the queries. By default, a `Map` is used.
 
 ## Global callbacks
 
diff --git a/packages/query-core/src/queryCache.ts b/packages/query-core/src/queryCache.ts
index 0b36901638..33ca767a2f 100644
--- a/packages/query-core/src/queryCache.ts
+++ b/packages/query-core/src/queryCache.ts
@@ -27,7 +27,6 @@ interface QueryCacheConfig {
     error: DefaultError | null,
     query: Query<unknown, unknown, unknown>,
   ) => void
-  createStore?: () => QueryStore
 }
 
 interface NotifyEventQueryAdded extends NotifyEvent {
@@ -95,7 +94,7 @@ export class QueryCache extends Subscribable<QueryCacheListener> {
 
   constructor(public config: QueryCacheConfig = {}) {
     super()
-    this.#queries = config.createStore?.() ?? new Map<string, Query>()
+    this.#queries = new Map<string, Query>()
   }
 
   build<TQueryFnData, TError, TData, TQueryKey extends QueryKey>(
diff --git a/packages/query-core/src/tests/queryCache.test.tsx b/packages/query-core/src/tests/queryCache.test.tsx
index 08edec68bb..8e328ae8fd 100644
--- a/packages/query-core/src/tests/queryCache.test.tsx
+++ b/packages/query-core/src/tests/queryCache.test.tsx
@@ -329,23 +329,6 @@ describe('queryCache', () => {
     })
   })
 
-  describe('QueryCacheConfig.createStore', () => {
-    test('should call createStore', async () => {
-      const createStore = vi.fn().mockImplementation(() => new Map())
-      new QueryCache({ createStore })
-      expect(createStore).toHaveBeenCalledWith()
-    })
-
-    test('should use created store', async () => {
-      const store = new Map()
-      const spy = vi.spyOn(store, 'get')
-
-      new QueryCache({ createStore: () => store }).get('key')
-
-      expect(spy).toHaveBeenCalledTimes(1)
-    })
-  })
-
   describe('QueryCache.add', () => {
     test('should not try to add a query already added to the cache', async () => {
       const key = queryKey()