Ensure Collection commits its updated information when nodes are removed (#5735)

Author: richardbann

packages/react-aria-components/src/Collection.tsx

@@ -605,7 +605,7 @@ export class Document<T, C extends BaseCollection<T> = BaseCollection<T>> extend
 
     this.dirtyNodes.clear();
 
-    if (this.mutatedNodes.size) {
+    if (this.mutatedNodes.size || this.collectionMutated) {
       let collection = this.getMutableCollection();
       for (let element of this.mutatedNodes) {
         if (element.isConnected) {
@@ -664,6 +664,7 @@ export function useCachedChildren<T extends object>(props: CachedChildrenOptions
   let {children, items, idScope, addIdAndValue, dependencies = []} = props;
 
   // Invalidate the cache whenever the parent value changes.
+  // eslint-disable-next-line react-hooks/exhaustive-deps
   let cache = useMemo(() => new WeakMap(), dependencies);
   return useMemo(() => {
     if (items && typeof children === 'function') {

packages/react-aria-components/test/Collection.test.js

@@ -0,0 +1,34 @@
+import {ListBoxItem} from '../src/ListBox';
+import React from 'react';
+import {render} from '@testing-library/react';
+import {useCollection} from '../src/Collection';
+
+
+const CollectionTest = (props) => {
+  const result = useCollection(props);
+  props.spyCollection.current = result.collection;
+  return <>{result.portal}</>;
+};
+
+const renderItems = (items, spyCollection) => (
+  <CollectionTest spyCollection={spyCollection}>
+    {items.map((item) => <ListBoxItem key={item} />)}
+  </CollectionTest>
+);
+
+describe('Collection', () => {
+  it('should be frozen even in case of empty initial collection', () => {
+    let spyCollection = {};
+    render(renderItems([], spyCollection));
+    expect(spyCollection.current.frozen).toBe(true);
+  });
+
+  it('should have correct firstKey, lastKey and should be frozen after all items are deleted', () => {
+    let spyCollection = {};
+    const {rerender} = render(renderItems(['a'], spyCollection));
+    rerender(renderItems([], spyCollection));
+    expect(spyCollection.current.frozen).toBe(true);
+    expect(spyCollection.current.firstKey).toBe(null);
+    expect(spyCollection.current.lastKey).toBe(null);
+  });
+});