fix: collections in react canary & next 16 app router

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

@@ -2396,6 +2396,55 @@ describe('ListBox', () => {
       expect(queryAllByRole('option')).toHaveLength(0);
     });
   }
+
+  if (React.version.startsWith('19')) {
+    it('supports Activity into a portal', async () => {
+      let ReactCanaryContext = React.createContext(null);
+      let RouterContext = React.createContext(null);
+
+      function Page() {
+        let {mode} = React.useContext(ReactCanaryContext);
+        let {pathname} = React.useContext(RouterContext);
+
+        return (
+          <>
+            <ol>
+              <li>{pathname}</li>
+            </ol>
+            <ListBox aria-label="Activity Listbox">
+              {mode === 'visible' && <ListBoxItem>Item 1</ListBoxItem>}
+              {mode === 'visible' && <ListBoxItem>Item 2</ListBoxItem>}
+              {mode === 'visible' && <ListBoxItem>Item 3</ListBoxItem>}
+              {mode === 'visible' && <ListBoxItem>Item 4</ListBoxItem>}
+              {mode === 'visible' && <ListBoxItem>Item 5</ListBoxItem>}
+            </ListBox>
+          </>
+        );
+      }
+
+      function App({mode, pathname = '/', ready = false}) {
+        let react = React.useMemo(() => ({mode}), [mode]);
+        let router = React.useMemo(() => ({pathname, ready}), [pathname, ready]);
+
+        let route = React.useMemo(() => <Page />, []);
+
+        return (
+          <RouterContext.Provider value={router}>
+            <ReactCanaryContext.Provider value={react}>
+              <React.Activity mode={mode}>{route}</React.Activity>
+            </ReactCanaryContext.Provider>
+          </RouterContext.Provider>
+        );
+      }
+
+      let {rerender, queryAllByRole} = render(<App mode="visible" pathname="/" ready />);
+      expect(queryAllByRole('option')).toHaveLength(5);
+      rerender(<App mode="hidden" pathname="/other" />);
+      rerender(<App mode="hidden" pathname="/other" ready />);
+      rerender(<App mode="visible" pathname="/" ready />);
+      expect(queryAllByRole('option')).toHaveLength(5);
+    });
+  }
 });
 
 describe('keyboard modifier keys', () => {

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

@@ -2976,12 +2976,12 @@ describe('Table', () => {
 
       await act(() => stories.makePromise([]));
 
-      expect(mockCollectionUpdate).toHaveBeenCalledTimes(1);
+      expect(mockCollectionUpdate).toHaveBeenCalledTimes(2);
 
       let button = tree.getByRole('button');
       await act(() => button.click());
 
-      expect(mockCollectionUpdate).toHaveBeenCalledTimes(2);
+      expect(mockCollectionUpdate).toHaveBeenCalledTimes(3);
     });
   });
 

packages/react-aria/src/collections/Document.ts

@@ -577,6 +577,12 @@ export class Document<T, C extends BaseCollection<T> = BaseCollection<T>> extend
 
   subscribe(fn: () => void) {
     this.subscriptions.add(fn);
+    // Ensure that React reads the collection if we re-subscribe after updates were
+    // already queued. When a hidden Activity is revealed, child nodes re-attach and call
+    // queueUpdate before we can re-subscribe, so the notification is lost.
+    if (this.queuedRender) {
+      fn();
+    }
     return (): boolean => this.subscriptions.delete(fn);
   }