feat(Worklets): runAsyncGuardedOnUI

[tjzel]

Summary

Previously the AsyncQueue of UIRuntime was always set to nullptr, making it impossible to invoke runGuardedAsync on it. I created a simple implementation of AsyncQueue for UI Runtime to enable that invocation. It's needed for asynchronous promise resolution on the UI Runtime.

Test plan

Apply the following diff and see that runOnRuntime with UIRuntime works properly.

diff --git a/apps/common-app/src/apps/reanimated/examples/EmptyExample.tsx b/apps/common-app/src/apps/reanimated/examples/EmptyExample.tsx
index 7f3a1ac26c..10d21761ab 100644
--- a/apps/common-app/src/apps/reanimated/examples/EmptyExample.tsx
+++ b/apps/common-app/src/apps/reanimated/examples/EmptyExample.tsx
@@ -1,10 +1,21 @@
 import React from 'react';
-import { StyleSheet, Text, View } from 'react-native';
+import { Button, StyleSheet, Text, View } from 'react-native';
+import { runOnRuntime } from 'react-native-worklets';
 
 export default function EmptyExample() {
   return (
     <View style={styles.container}>
       <Text>Hello world!</Text>
+      <Button
+        title="Run on UI Runtime"
+        onPress={() => {
+          const UIRuntimeRef = globalThis.__UIRuntimeRef;
+          runOnRuntime(UIRuntimeRef, () => {
+            'worklet';
+            console.log('This is running on the UI runtime with UIAsyncQueue');
+          })();
+        }}
+      />
     </View>
   );
 }
diff --git a/packages/react-native-worklets/android/src/main/cpp/worklets/android/WorkletsModule.cpp b/packages/react-native-worklets/android/src/main/cpp/worklets/android/WorkletsModule.cpp
index 84979ee67e..6622d138fe 100644
--- a/packages/react-native-worklets/android/src/main/cpp/worklets/android/WorkletsModule.cpp
+++ b/packages/react-native-worklets/android/src/main/cpp/worklets/android/WorkletsModule.cpp
@@ -1,3 +1,4 @@
+#include <jsi/jsi.h>
 #include <worklets/NativeModules/JSIWorkletsModuleProxy.h>
 #include <worklets/Tools/WorkletsJSIUtils.h>
 #include <worklets/WorkletRuntime/RNRuntimeWorkletDecorator.h>
@@ -33,6 +34,11 @@ WorkletsModule::WorkletsModule(
           sourceURL)) {
   auto jsiWorkletsModuleProxy =
       workletsModuleProxy_->createJSIWorkletsModuleProxy();
+  auto uiRuntimeRef = jsi::Object::createFromHostObject(
+      *rnRuntime, jsiWorkletsModuleProxy->getRuntimeManager()->getUIRuntime());
+  rnRuntime_->global().setProperty(
+      *rnRuntime_, "__UIRuntimeRef", std::move(uiRuntimeRef));
+
   auto optimizedJsiWorkletsModuleProxy = jsi_utils::optimizedFromHostObject(
       *rnRuntime_,
       std::static_pointer_cast<jsi::HostObject>(

[Copilot]

Pull Request Overview

This PR adds asynchronous execution support to the UI Runtime by implementing an AsyncQueue for the UIRuntime. Previously, the UI Runtime's AsyncQueue was always null, preventing the use of runAsyncGuarded functionality needed for asynchronous promise resolution.

Key changes:

• Created AsyncQueueUI class that uses UIScheduler for async execution on UI thread
• Modified RuntimeManager to accept an AsyncQueue parameter for UI runtime creation
• Refactored runAsyncGuarded implementation to move from header to implementation file

Reviewed Changes

Copilot reviewed 7 out of 7 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
WorkletRuntime.h	Moved runAsyncGuarded method declaration from inline to separate implementation
WorkletRuntime.cpp	Added implementation of runAsyncGuarded with improved error messaging
RuntimeManager.h	Updated createUninitializedUIRuntime to accept AsyncQueue parameter
RuntimeManager.cpp	Modified UI runtime creation to use provided AsyncQueue
AsyncQueueImpl.h	Added AsyncQueueUI class declaration
AsyncQueueImpl.cpp	Implemented AsyncQueueUI using UIScheduler for UI thread execution
WorkletsModuleProxy.cpp	Updated to create UI runtime with new AsyncQueueUI instance