fix[devtools/useTransition]: don't check for dispatch property when determining if hook is stateful (#27365)

hoxyq · web-flow · commit 56b14477e902 · 2023-09-21T21:26:20.000+01:00
#26740 introduced regression: React DevTools doesn't record updates for `useTransition` hook. I can add more details about things on DevTools side, if needed. The root cause is https://github.com/facebook/react/blob/491aec5d6113ce5bae7c10966bc38a4a8fc091a8/packages/react-reconciler/src/ReactFiberHooks.js#L2728-L2730 React DevTools expects dispatch to be present for stateful hooks that can schedule an update - https://github.com/facebook/react/blob/2eed1328478e8c923fcb4e6abf5efbd9e1233402/packages/react-devtools-shared/src/backend/renderer.js#L1422-L1428 With these changes, we still call dispatch in `startTransition`, but also patch `queue` object with it, so that React DevTools can recognise `useTransition` as stateful hook that can schedule update. I am not sure if this is the right approach to fix this, can we distinguish if `startTransition` was called from `useTransition` hook or as a standalone function?
diff --git a/packages/react-devtools-shared/src/backend/renderer.js b/packages/react-devtools-shared/src/backend/renderer.js
@@ -1419,22 +1419,20 @@ export function attach(
 
     const boundHasOwnProperty = hasOwnProperty.bind(queue);
 
-    // Detect the shape of useState() or useReducer()
+    // Detect the shape of useState() / useReducer() / useTransition()
     // using the attributes that are unique to these hooks
     // but also stable (e.g. not tied to current Lanes implementation)
-    const isStateOrReducer =
-      boundHasOwnProperty('pending') &&
-      boundHasOwnProperty('dispatch') &&
-      typeof queue.dispatch === 'function';
+    // We don't check for dispatch property, because useTransition doesn't have it
+    if (boundHasOwnProperty('pending')) {
+      return true;
+    }
 
     // Detect useSyncExternalStore()
-    const isSyncExternalStore =
+    return (
       boundHasOwnProperty('value') &&
       boundHasOwnProperty('getSnapshot') &&
-      typeof queue.getSnapshot === 'function';
-
-    // These are the only types of hooks that can schedule an update.
-    return isStateOrReducer || isSyncExternalStore;
+      typeof queue.getSnapshot === 'function'
+    );
   }
 
   function didStatefulHookChange(prev: any, next: any): boolean {
