perf(query-core): useQueries have quadratic performance in relation to the number of queries(#8604)

Author: scl

packages/query-core/src/queriesObserver.ts

@@ -44,6 +44,7 @@ export class QueriesObserver<
   #lastCombine?: CombineFn<TCombinedResult>
   #lastResult?: Array<QueryObserverResult>
   #observerMatches: Array<QueryObserverMatch> = []
+  #observerMap: Map<QueryObserver, number> = new Map()
 
   constructor(
     client: QueryClient,
@@ -130,6 +131,11 @@ export class QueriesObserver<
       this.#observers = newObservers
       this.#result = newResult
 
+      this.#observerMap.clear()
+      newObservers.forEach((observer, index) => {
+        this.#observerMap.set(observer, index)
+      })
+
       if (!this.hasListeners()) {
         return
       }
@@ -253,8 +259,8 @@ export class QueriesObserver<
   }
 
   #onUpdate(observer: QueryObserver, result: QueryObserverResult): void {
-    const index = this.#observers.indexOf(observer)
-    if (index !== -1) {
+    const index = this.#observerMap.get(observer)
+    if (index !== undefined) {
       this.#result = replaceAt(this.#result, index, result)
       this.#notify()
     }