Fix Android JSC compatibility - replaceAll -> replace

Summary:
JSC for Android does not implement `String.prototype.replaceAll`:

 {F1971791988} 

https://github.com/facebook/react-native/pull/47466 introduced a use of it into runtime code, breaking JSC compatibility.

This.. replaces it.. with `replace`. Since the argument is already a regex with a `g` modifier, `replaceAll` wasn't necessary anyway.

Changelog:
[ANDROID][FIXED] Fix JSC by avoiding use of unavailable `str.replaceAll()`

Differential Revision: D66712312

packages/polyfills/console.js

@@ -559,7 +559,7 @@ if (global.nativeLoggingHook) {
     let originalConsoleError = console.error;
     console.reportErrorsAsExceptions = true;
     function stringifySafe(arg) {
-      return inspect(arg, {depth: 10}).replaceAll(/\n\s*/g, ' ');
+      return inspect(arg, {depth: 10}).replace(/\n\s*/g, ' ');
     }
     console.error = function (...args) {
       originalConsoleError.apply(this, args);

packages/react-native/ReactAndroid/src/main/java/com/facebook/react/internal/featureflags/ReactNativeFeatureFlags.kt

@@ -4,7 +4,7 @@
  * This source code is licensed under the MIT license found in the
  * LICENSE file in the root directory of this source tree.
  *
- * @generated SignedSource<<6d8d8f4b81d7be882b315d0960499dcb>>
+ * @generated SignedSource<<4a219bb47b1b9d988a164bca19eb4fa9>>
  */
 
 /**
@@ -202,6 +202,12 @@ public object ReactNativeFeatureFlags {
   @JvmStatic
   public fun excludeYogaFromRawProps(): Boolean = accessor.excludeYogaFromRawProps()
 
+  /**
+   * Fixes a bug in Differentiator where parent views may be referenced before they're created
+   */
+  @JvmStatic
+  public fun fixDifferentiatorEmittingUpdatesWithWrongParentTag(): Boolean = accessor.fixDifferentiatorEmittingUpdatesWithWrongParentTag()
+
   /**
    * Uses the default event priority instead of the discreet event priority by default when dispatching events from Fabric to React.
    */

packages/react-native/ReactAndroid/src/main/java/com/facebook/react/internal/featureflags/ReactNativeFeatureFlagsCxxAccessor.kt

@@ -4,7 +4,7 @@
  * This source code is licensed under the MIT license found in the
  * LICENSE file in the root directory of this source tree.
  *
- * @generated SignedSource<<031fce8e8b4c20a3e3d6dbecf94d138a>>
+ * @generated SignedSource<<d75efd6beee8dd9d38b5d648fbecbcda>>
  */
 
 /**
@@ -49,6 +49,7 @@ public class ReactNativeFeatureFlagsCxxAccessor : ReactNativeFeatureFlagsAccesso
   private var enableUIConsistencyCache: Boolean? = null
   private var enableViewRecyclingCache: Boolean? = null
   private var excludeYogaFromRawPropsCache: Boolean? = null
+  private var fixDifferentiatorEmittingUpdatesWithWrongParentTagCache: Boolean? = null
   private var fixMappingOfEventPrioritiesBetweenFabricAndReactCache: Boolean? = null
   private var fixMountingCoordinatorReportedPendingTransactionsOnAndroidCache: Boolean? = null
   private var fuseboxEnabledDebugCache: Boolean? = null
@@ -328,6 +329,15 @@ public class ReactNativeFeatureFlagsCxxAccessor : ReactNativeFeatureFlagsAccesso
     return cached
   }
 
+  override fun fixDifferentiatorEmittingUpdatesWithWrongParentTag(): Boolean {
+    var cached = fixDifferentiatorEmittingUpdatesWithWrongParentTagCache
+    if (cached == null) {
+      cached = ReactNativeFeatureFlagsCxxInterop.fixDifferentiatorEmittingUpdatesWithWrongParentTag()
+      fixDifferentiatorEmittingUpdatesWithWrongParentTagCache = cached
+    }
+    return cached
+  }
+
   override fun fixMappingOfEventPrioritiesBetweenFabricAndReact(): Boolean {
     var cached = fixMappingOfEventPrioritiesBetweenFabricAndReactCache
     if (cached == null) {

packages/react-native/ReactAndroid/src/main/java/com/facebook/react/internal/featureflags/ReactNativeFeatureFlagsCxxInterop.kt

@@ -4,7 +4,7 @@
  * This source code is licensed under the MIT license found in the
  * LICENSE file in the root directory of this source tree.
  *
- * @generated SignedSource<<35811667ac2543e1f64e27bbdb483ec1>>
+ * @generated SignedSource<<7454ab19a01cfbb0a54f14bd83fc3a90>>
  */
 
 /**
@@ -86,6 +86,8 @@ public object ReactNativeFeatureFlagsCxxInterop {
 
   @DoNotStrip @JvmStatic public external fun excludeYogaFromRawProps(): Boolean
 
+  @DoNotStrip @JvmStatic public external fun fixDifferentiatorEmittingUpdatesWithWrongParentTag(): Boolean
+
   @DoNotStrip @JvmStatic public external fun fixMappingOfEventPrioritiesBetweenFabricAndReact(): Boolean
 
   @DoNotStrip @JvmStatic public external fun fixMountingCoordinatorReportedPendingTransactionsOnAndroid(): Boolean

packages/react-native/ReactAndroid/src/main/java/com/facebook/react/internal/featureflags/ReactNativeFeatureFlagsDefaults.kt

@@ -4,7 +4,7 @@
  * This source code is licensed under the MIT license found in the
  * LICENSE file in the root directory of this source tree.
  *
- * @generated SignedSource<<9d829c58e49164a0b2b6b66bc0ce088a>>
+ * @generated SignedSource<<70d951b2956759280afae4af8f9a2869>>
  */
 
 /**
@@ -81,6 +81,8 @@ public open class ReactNativeFeatureFlagsDefaults : ReactNativeFeatureFlagsProvi
 
   override fun excludeYogaFromRawProps(): Boolean = false
 
+  override fun fixDifferentiatorEmittingUpdatesWithWrongParentTag(): Boolean = true
+
   override fun fixMappingOfEventPrioritiesBetweenFabricAndReact(): Boolean = false
 
   override fun fixMountingCoordinatorReportedPendingTransactionsOnAndroid(): Boolean = false

packages/react-native/ReactAndroid/src/main/java/com/facebook/react/internal/featureflags/ReactNativeFeatureFlagsLocalAccessor.kt

@@ -4,7 +4,7 @@
  * This source code is licensed under the MIT license found in the
  * LICENSE file in the root directory of this source tree.
  *
- * @generated SignedSource<<0121e113410a5b0e14eaf74a3076df2f>>
+ * @generated SignedSource<<f60000cb58a9632c3aa193854be3de4e>>
  */
 
 /**
@@ -53,6 +53,7 @@ public class ReactNativeFeatureFlagsLocalAccessor : ReactNativeFeatureFlagsAcces
   private var enableUIConsistencyCache: Boolean? = null
   private var enableViewRecyclingCache: Boolean? = null
   private var excludeYogaFromRawPropsCache: Boolean? = null
+  private var fixDifferentiatorEmittingUpdatesWithWrongParentTagCache: Boolean? = null
   private var fixMappingOfEventPrioritiesBetweenFabricAndReactCache: Boolean? = null
   private var fixMountingCoordinatorReportedPendingTransactionsOnAndroidCache: Boolean? = null
   private var fuseboxEnabledDebugCache: Boolean? = null
@@ -361,6 +362,16 @@ public class ReactNativeFeatureFlagsLocalAccessor : ReactNativeFeatureFlagsAcces
     return cached
   }
 
+  override fun fixDifferentiatorEmittingUpdatesWithWrongParentTag(): Boolean {
+    var cached = fixDifferentiatorEmittingUpdatesWithWrongParentTagCache
+    if (cached == null) {
+      cached = currentProvider.fixDifferentiatorEmittingUpdatesWithWrongParentTag()
+      accessedFeatureFlags.add("fixDifferentiatorEmittingUpdatesWithWrongParentTag")
+      fixDifferentiatorEmittingUpdatesWithWrongParentTagCache = cached
+    }
+    return cached
+  }
+
   override fun fixMappingOfEventPrioritiesBetweenFabricAndReact(): Boolean {
     var cached = fixMappingOfEventPrioritiesBetweenFabricAndReactCache
     if (cached == null) {

packages/react-native/ReactAndroid/src/main/java/com/facebook/react/internal/featureflags/ReactNativeFeatureFlagsProvider.kt

@@ -4,7 +4,7 @@
  * This source code is licensed under the MIT license found in the
  * LICENSE file in the root directory of this source tree.
  *
- * @generated SignedSource<<2787d9027695dd14ec6b917a32a1a6de>>
+ * @generated SignedSource<<d62af893c5d18a2152f098ff305ae41e>>
  */
 
 /**
@@ -81,6 +81,8 @@ public interface ReactNativeFeatureFlagsProvider {
 
   @DoNotStrip public fun excludeYogaFromRawProps(): Boolean
 
+  @DoNotStrip public fun fixDifferentiatorEmittingUpdatesWithWrongParentTag(): Boolean
+
   @DoNotStrip public fun fixMappingOfEventPrioritiesBetweenFabricAndReact(): Boolean
 
   @DoNotStrip public fun fixMountingCoordinatorReportedPendingTransactionsOnAndroid(): Boolean

packages/react-native/ReactAndroid/src/main/java/com/facebook/react/uimanager/RootView.kt

@@ -5,10 +5,10 @@
  * LICENSE file in the root directory of this source tree.
  */
 
-package com.facebook.react.uimanager;
+package com.facebook.react.uimanager
 
-import android.view.MotionEvent;
-import android.view.View;
+import android.view.MotionEvent
+import android.view.View
 
 /** Interface for the root native view of a React native application. */
 public interface RootView {
@@ -17,21 +17,20 @@ public interface RootView {
    * Called when a child starts a native gesture (e.g. a scroll in a ScrollView). Should be called
    * from the child's onTouchIntercepted implementation.
    */
-  void onChildStartedNativeGesture(View childView, MotionEvent ev);
+  public fun onChildStartedNativeGesture(childView: View?, ev: MotionEvent)
 
-  /**
-   * @deprecated
-   */
-  @Deprecated
-  default void onChildStartedNativeGesture(MotionEvent ev) {
-    onChildStartedNativeGesture(null, ev);
+  @Deprecated(
+      message = "Use onChildStartedNativeGesture with a childView parameter.",
+      replaceWith = ReplaceWith("onChildStartedNativeGesture"))
+  public fun onChildStartedNativeGesture(ev: MotionEvent) {
+    onChildStartedNativeGesture(null, ev)
   }
 
   /**
    * Called when a child ends a native gesture. Should be called from the child's onTouchIntercepted
    * implementation.
    */
-  void onChildEndedNativeGesture(View childView, MotionEvent ev);
+  public fun onChildEndedNativeGesture(childView: View, ev: MotionEvent)
 
-  void handleException(Throwable t);
+  public fun handleException(t: Throwable)
 }

packages/react-native/ReactAndroid/src/main/java/com/facebook/react/views/modal/ReactModalHostView.kt

@@ -495,7 +495,7 @@ public class ReactModalHostView(context: ThemedReactContext) :
       return super.onHoverEvent(event)
     }
 
-    override fun onChildStartedNativeGesture(childView: View, ev: MotionEvent) {
+    override fun onChildStartedNativeGesture(childView: View?, ev: MotionEvent) {
       eventDispatcher?.let { eventDispatcher ->
         jSTouchDispatcher.onChildStartedNativeGesture(ev, eventDispatcher)
         jSPointerDispatcher?.onChildStartedNativeGesture(childView, ev, eventDispatcher)

packages/react-native/ReactAndroid/src/main/jni/react/featureflags/JReactNativeFeatureFlagsCxxInterop.cpp

@@ -4,7 +4,7 @@
  * This source code is licensed under the MIT license found in the
  * LICENSE file in the root directory of this source tree.
  *
- * @generated SignedSource<<902b269e45fcb4970c6f8a86818e1940>>
+ * @generated SignedSource<<640630d7a40b53f7d507569aa6409f69>>
  */
 
 /**
@@ -213,6 +213,12 @@ class ReactNativeFeatureFlagsProviderHolder
     return method(javaProvider_);
   }
 
+  bool fixDifferentiatorEmittingUpdatesWithWrongParentTag() override {
+    static const auto method =
+        getReactNativeFeatureFlagsProviderJavaClass()->getMethod<jboolean()>("fixDifferentiatorEmittingUpdatesWithWrongParentTag");
+    return method(javaProvider_);
+  }
+
   bool fixMappingOfEventPrioritiesBetweenFabricAndReact() override {
     static const auto method =
         getReactNativeFeatureFlagsProviderJavaClass()->getMethod<jboolean()>("fixMappingOfEventPrioritiesBetweenFabricAndReact");
@@ -464,6 +470,11 @@ bool JReactNativeFeatureFlagsCxxInterop::excludeYogaFromRawProps(
   return ReactNativeFeatureFlags::excludeYogaFromRawProps();
 }
 
+bool JReactNativeFeatureFlagsCxxInterop::fixDifferentiatorEmittingUpdatesWithWrongParentTag(
+    facebook::jni::alias_ref<JReactNativeFeatureFlagsCxxInterop> /*unused*/) {
+  return ReactNativeFeatureFlags::fixDifferentiatorEmittingUpdatesWithWrongParentTag();
+}
+
 bool JReactNativeFeatureFlagsCxxInterop::fixMappingOfEventPrioritiesBetweenFabricAndReact(
     facebook::jni::alias_ref<JReactNativeFeatureFlagsCxxInterop> /*unused*/) {
   return ReactNativeFeatureFlags::fixMappingOfEventPrioritiesBetweenFabricAndReact();
@@ -667,6 +678,9 @@ void JReactNativeFeatureFlagsCxxInterop::registerNatives() {
       makeNativeMethod(
         "excludeYogaFromRawProps",
         JReactNativeFeatureFlagsCxxInterop::excludeYogaFromRawProps),
+      makeNativeMethod(
+        "fixDifferentiatorEmittingUpdatesWithWrongParentTag",
+        JReactNativeFeatureFlagsCxxInterop::fixDifferentiatorEmittingUpdatesWithWrongParentTag),
       makeNativeMethod(
         "fixMappingOfEventPrioritiesBetweenFabricAndReact",
         JReactNativeFeatureFlagsCxxInterop::fixMappingOfEventPrioritiesBetweenFabricAndReact),

packages/react-native/ReactAndroid/src/main/jni/react/featureflags/JReactNativeFeatureFlagsCxxInterop.h

@@ -4,7 +4,7 @@
  * This source code is licensed under the MIT license found in the
  * LICENSE file in the root directory of this source tree.
  *
- * @generated SignedSource<<17da0d7937c5c0c533293b86c8cdc9be>>
+ * @generated SignedSource<<4218168e779a2241d0752771c1f51b12>>
  */
 
 /**
@@ -117,6 +117,9 @@ class JReactNativeFeatureFlagsCxxInterop
   static bool excludeYogaFromRawProps(
     facebook::jni::alias_ref<JReactNativeFeatureFlagsCxxInterop>);
 
+  static bool fixDifferentiatorEmittingUpdatesWithWrongParentTag(
+    facebook::jni::alias_ref<JReactNativeFeatureFlagsCxxInterop>);
+
   static bool fixMappingOfEventPrioritiesBetweenFabricAndReact(
     facebook::jni::alias_ref<JReactNativeFeatureFlagsCxxInterop>);
 

packages/react-native/ReactCommon/jsinspector-modern/React-jsinspector.podspec

@@ -20,31 +20,39 @@ folly_config = get_folly_config()
 folly_compiler_flags = folly_config[:compiler_flags]
 folly_version = folly_config[:version]
 
-use_frameworks = ENV['USE_FRAMEWORKS'] != nil
+header_search_paths = [
+  "\"$(PODS_TARGET_SRCROOT)/..\"",
+  "\"$(PODS_ROOT)/boost\"",
+  "\"$(PODS_ROOT)/DoubleConversion\"",
+  "\"$(PODS_ROOT)/fast_float/include\"",
+  "\"$(PODS_ROOT)/fmt/include\"",
+  "\"$(PODS_ROOT)/RCT-Folly\"",
+]
 
 header_dir = 'jsinspector-modern'
 module_name = "jsinspector_modern"
+
 Pod::Spec.new do |s|
   s.name                   = "React-jsinspector"
   s.version                = version
-  s.summary                = "-"  # TODO
+  s.summary                = "React Native subsystem for modern debugging over the Chrome DevTools Protocol (CDP)"
   s.homepage               = "https://reactnative.dev/"
   s.license                = package["license"]
   s.author                 = "Meta Platforms, Inc. and its affiliates"
   s.platforms              = min_supported_versions
   s.source                 = source
   s.source_files           = "*.{cpp,h,def}"
-  s.header_dir             = 'jsinspector-modern'
+  s.header_dir             = header_dir
   s.compiler_flags         = folly_compiler_flags
   s.pod_target_xcconfig    = {
-                               "HEADER_SEARCH_PATHS" => "\"$(PODS_TARGET_SRCROOT)/..\" \"$(PODS_ROOT)/boost\" \"$(PODS_ROOT)/RCT-Folly\" \"$(PODS_ROOT)/DoubleConversion\" \"$(PODS_ROOT)/fast_float/include\" \"$(PODS_ROOT)/fmt/include\"",
+                               "HEADER_SEARCH_PATHS" => header_search_paths.join(' '),
                                "CLANG_CXX_LANGUAGE_STANDARD" => rct_cxx_language_standard(),
                                "DEFINES_MODULE" => "YES"
-  }.merge!(use_frameworks ? {
+  }.merge!(ENV['USE_FRAMEWORKS'] ? {
     "PUBLIC_HEADERS_FOLDER_PATH" => "#{module_name}.framework/Headers/#{header_dir}"
   } : {})
 
-  if use_frameworks
+  if ENV['USE_FRAMEWORKS']
     s.module_name = module_name
   end
 

packages/react-native/ReactCommon/react/featureflags/ReactNativeFeatureFlags.cpp

@@ -4,7 +4,7 @@
  * This source code is licensed under the MIT license found in the
  * LICENSE file in the root directory of this source tree.
  *
- * @generated SignedSource<<ef215623465d45c563030d724287b1c9>>
+ * @generated SignedSource<<2409869111055ff0b32c1f40c10042d7>>
  */
 
 /**
@@ -142,6 +142,10 @@ bool ReactNativeFeatureFlags::excludeYogaFromRawProps() {
   return getAccessor().excludeYogaFromRawProps();
 }
 
+bool ReactNativeFeatureFlags::fixDifferentiatorEmittingUpdatesWithWrongParentTag() {
+  return getAccessor().fixDifferentiatorEmittingUpdatesWithWrongParentTag();
+}
+
 bool ReactNativeFeatureFlags::fixMappingOfEventPrioritiesBetweenFabricAndReact() {
   return getAccessor().fixMappingOfEventPrioritiesBetweenFabricAndReact();
 }

packages/react-native/ReactCommon/react/featureflags/ReactNativeFeatureFlags.h

@@ -4,7 +4,7 @@
  * This source code is licensed under the MIT license found in the
  * LICENSE file in the root directory of this source tree.
  *
- * @generated SignedSource<<f741660e4cf2528defe0ab1f61858aab>>
+ * @generated SignedSource<<e628af8109a1d8bb6425515d824852a3>>
  */
 
 /**
@@ -184,6 +184,11 @@ class ReactNativeFeatureFlags {
    */
   RN_EXPORT static bool excludeYogaFromRawProps();
 
+  /**
+   * Fixes a bug in Differentiator where parent views may be referenced before they're created
+   */
+  RN_EXPORT static bool fixDifferentiatorEmittingUpdatesWithWrongParentTag();
+
   /**
    * Uses the default event priority instead of the discreet event priority by default when dispatching events from Fabric to React.
    */

packages/react-native/ReactCommon/react/featureflags/ReactNativeFeatureFlagsAccessor.cpp

@@ -4,7 +4,7 @@
  * This source code is licensed under the MIT license found in the
  * LICENSE file in the root directory of this source tree.
  *
- * @generated SignedSource<<4c3956150bbf826c2abf4f8daf569b88>>
+ * @generated SignedSource<<1e5b87b564e880cfb1423a85692092ba>>
  */
 
 /**
@@ -551,6 +551,24 @@ bool ReactNativeFeatureFlagsAccessor::excludeYogaFromRawProps() {
   return flagValue.value();
 }
 
+bool ReactNativeFeatureFlagsAccessor::fixDifferentiatorEmittingUpdatesWithWrongParentTag() {
+  auto flagValue = fixDifferentiatorEmittingUpdatesWithWrongParentTag_.load();
+
+  if (!flagValue.has_value()) {
+    // This block is not exclusive but it is not necessary.
+    // If multiple threads try to initialize the feature flag, we would only
+    // be accessing the provider multiple times but the end state of this
+    // instance and the returned flag value would be the same.
+
+    markFlagAsAccessed(29, "fixDifferentiatorEmittingUpdatesWithWrongParentTag");
+
+    flagValue = currentProvider_->fixDifferentiatorEmittingUpdatesWithWrongParentTag();
+    fixDifferentiatorEmittingUpdatesWithWrongParentTag_ = flagValue;
+  }
+
+  return flagValue.value();
+}
+
 bool ReactNativeFeatureFlagsAccessor::fixMappingOfEventPrioritiesBetweenFabricAndReact() {
   auto flagValue = fixMappingOfEventPrioritiesBetweenFabricAndReact_.load();
 
@@ -560,7 +578,7 @@ bool ReactNativeFeatureFlagsAccessor::fixMappingOfEventPrioritiesBetweenFabricAn
     // be accessing the provider multiple times but the end state of this
     // instance and the returned flag value would be the same.
 
-    markFlagAsAccessed(29, "fixMappingOfEventPrioritiesBetweenFabricAndReact");
+    markFlagAsAccessed(30, "fixMappingOfEventPrioritiesBetweenFabricAndReact");
 
     flagValue = currentProvider_->fixMappingOfEventPrioritiesBetweenFabricAndReact();
     fixMappingOfEventPrioritiesBetweenFabricAndReact_ = flagValue;
@@ -578,7 +596,7 @@ bool ReactNativeFeatureFlagsAccessor::fixMountingCoordinatorReportedPendingTrans
     // be accessing the provider multiple times but the end state of this
     // instance and the returned flag value would be the same.
 
-    markFlagAsAccessed(30, "fixMountingCoordinatorReportedPendingTransactionsOnAndroid");
+    markFlagAsAccessed(31, "fixMountingCoordinatorReportedPendingTransactionsOnAndroid");
 
     flagValue = currentProvider_->fixMountingCoordinatorReportedPendingTransactionsOnAndroid();
     fixMountingCoordinatorReportedPendingTransactionsOnAndroid_ = flagValue;
@@ -596,7 +614,7 @@ bool ReactNativeFeatureFlagsAccessor::fuseboxEnabledDebug() {
     // be accessing the provider multiple times but the end state of this
     // instance and the returned flag value would be the same.
 
-    markFlagAsAccessed(31, "fuseboxEnabledDebug");
+    markFlagAsAccessed(32, "fuseboxEnabledDebug");
 
     flagValue = currentProvider_->fuseboxEnabledDebug();
     fuseboxEnabledDebug_ = flagValue;
@@ -614,7 +632,7 @@ bool ReactNativeFeatureFlagsAccessor::fuseboxEnabledRelease() {
     // be accessing the provider multiple times but the end state of this
     // instance and the returned flag value would be the same.
 
-    markFlagAsAccessed(32, "fuseboxEnabledRelease");
+    markFlagAsAccessed(33, "fuseboxEnabledRelease");
 
     flagValue = currentProvider_->fuseboxEnabledRelease();
     fuseboxEnabledRelease_ = flagValue;
@@ -632,7 +650,7 @@ bool ReactNativeFeatureFlagsAccessor::initEagerTurboModulesOnNativeModulesQueueA
     // be accessing the provider multiple times but the end state of this
     // instance and the returned flag value would be the same.
 
-    markFlagAsAccessed(33, "initEagerTurboModulesOnNativeModulesQueueAndroid");
+    markFlagAsAccessed(34, "initEagerTurboModulesOnNativeModulesQueueAndroid");
 
     flagValue = currentProvider_->initEagerTurboModulesOnNativeModulesQueueAndroid();
     initEagerTurboModulesOnNativeModulesQueueAndroid_ = flagValue;
@@ -650,7 +668,7 @@ bool ReactNativeFeatureFlagsAccessor::lazyAnimationCallbacks() {
     // be accessing the provider multiple times but the end state of this
     // instance and the returned flag value would be the same.
 
-    markFlagAsAccessed(34, "lazyAnimationCallbacks");
+    markFlagAsAccessed(35, "lazyAnimationCallbacks");
 
     flagValue = currentProvider_->lazyAnimationCallbacks();
     lazyAnimationCallbacks_ = flagValue;
@@ -668,7 +686,7 @@ bool ReactNativeFeatureFlagsAccessor::loadVectorDrawablesOnImages() {
     // be accessing the provider multiple times but the end state of this
     // instance and the returned flag value would be the same.
 
-    markFlagAsAccessed(35, "loadVectorDrawablesOnImages");
+    markFlagAsAccessed(36, "loadVectorDrawablesOnImages");
 
     flagValue = currentProvider_->loadVectorDrawablesOnImages();
     loadVectorDrawablesOnImages_ = flagValue;
@@ -686,7 +704,7 @@ bool ReactNativeFeatureFlagsAccessor::traceTurboModulePromiseRejectionsOnAndroid
     // be accessing the provider multiple times but the end state of this
     // instance and the returned flag value would be the same.
 
-    markFlagAsAccessed(36, "traceTurboModulePromiseRejectionsOnAndroid");
+    markFlagAsAccessed(37, "traceTurboModulePromiseRejectionsOnAndroid");
 
     flagValue = currentProvider_->traceTurboModulePromiseRejectionsOnAndroid();
     traceTurboModulePromiseRejectionsOnAndroid_ = flagValue;
@@ -704,7 +722,7 @@ bool ReactNativeFeatureFlagsAccessor::useAlwaysAvailableJSErrorHandling() {
     // be accessing the provider multiple times but the end state of this
     // instance and the returned flag value would be the same.
 
-    markFlagAsAccessed(37, "useAlwaysAvailableJSErrorHandling");
+    markFlagAsAccessed(38, "useAlwaysAvailableJSErrorHandling");
 
     flagValue = currentProvider_->useAlwaysAvailableJSErrorHandling();
     useAlwaysAvailableJSErrorHandling_ = flagValue;
@@ -722,7 +740,7 @@ bool ReactNativeFeatureFlagsAccessor::useFabricInterop() {
     // be accessing the provider multiple times but the end state of this
     // instance and the returned flag value would be the same.
 
-    markFlagAsAccessed(38, "useFabricInterop");
+    markFlagAsAccessed(39, "useFabricInterop");
 
     flagValue = currentProvider_->useFabricInterop();
     useFabricInterop_ = flagValue;
@@ -740,7 +758,7 @@ bool ReactNativeFeatureFlagsAccessor::useImmediateExecutorInAndroidBridgeless()
     // be accessing the provider multiple times but the end state of this
     // instance and the returned flag value would be the same.
 
-    markFlagAsAccessed(39, "useImmediateExecutorInAndroidBridgeless");
+    markFlagAsAccessed(40, "useImmediateExecutorInAndroidBridgeless");
 
     flagValue = currentProvider_->useImmediateExecutorInAndroidBridgeless();
     useImmediateExecutorInAndroidBridgeless_ = flagValue;
@@ -758,7 +776,7 @@ bool ReactNativeFeatureFlagsAccessor::useNativeViewConfigsInBridgelessMode() {
     // be accessing the provider multiple times but the end state of this
     // instance and the returned flag value would be the same.
 
-    markFlagAsAccessed(40, "useNativeViewConfigsInBridgelessMode");
+    markFlagAsAccessed(41, "useNativeViewConfigsInBridgelessMode");
 
     flagValue = currentProvider_->useNativeViewConfigsInBridgelessMode();
     useNativeViewConfigsInBridgelessMode_ = flagValue;
@@ -776,7 +794,7 @@ bool ReactNativeFeatureFlagsAccessor::useOptimisedViewPreallocationOnAndroid() {
     // be accessing the provider multiple times but the end state of this
     // instance and the returned flag value would be the same.
 
-    markFlagAsAccessed(41, "useOptimisedViewPreallocationOnAndroid");
+    markFlagAsAccessed(42, "useOptimisedViewPreallocationOnAndroid");
 
     flagValue = currentProvider_->useOptimisedViewPreallocationOnAndroid();
     useOptimisedViewPreallocationOnAndroid_ = flagValue;
@@ -794,7 +812,7 @@ bool ReactNativeFeatureFlagsAccessor::useOptimizedEventBatchingOnAndroid() {
     // be accessing the provider multiple times but the end state of this
     // instance and the returned flag value would be the same.
 
-    markFlagAsAccessed(42, "useOptimizedEventBatchingOnAndroid");
+    markFlagAsAccessed(43, "useOptimizedEventBatchingOnAndroid");
 
     flagValue = currentProvider_->useOptimizedEventBatchingOnAndroid();
     useOptimizedEventBatchingOnAndroid_ = flagValue;
@@ -812,7 +830,7 @@ bool ReactNativeFeatureFlagsAccessor::useRuntimeShadowNodeReferenceUpdate() {
     // be accessing the provider multiple times but the end state of this
     // instance and the returned flag value would be the same.
 
-    markFlagAsAccessed(43, "useRuntimeShadowNodeReferenceUpdate");
+    markFlagAsAccessed(44, "useRuntimeShadowNodeReferenceUpdate");
 
     flagValue = currentProvider_->useRuntimeShadowNodeReferenceUpdate();
     useRuntimeShadowNodeReferenceUpdate_ = flagValue;
@@ -830,7 +848,7 @@ bool ReactNativeFeatureFlagsAccessor::useTurboModuleInterop() {
     // be accessing the provider multiple times but the end state of this
     // instance and the returned flag value would be the same.
 
-    markFlagAsAccessed(44, "useTurboModuleInterop");
+    markFlagAsAccessed(45, "useTurboModuleInterop");
 
     flagValue = currentProvider_->useTurboModuleInterop();
     useTurboModuleInterop_ = flagValue;
@@ -848,7 +866,7 @@ bool ReactNativeFeatureFlagsAccessor::useTurboModules() {
     // be accessing the provider multiple times but the end state of this
     // instance and the returned flag value would be the same.
 
-    markFlagAsAccessed(45, "useTurboModules");
+    markFlagAsAccessed(46, "useTurboModules");
 
     flagValue = currentProvider_->useTurboModules();
     useTurboModules_ = flagValue;

packages/react-native/ReactCommon/react/featureflags/ReactNativeFeatureFlagsAccessor.h

@@ -4,7 +4,7 @@
  * This source code is licensed under the MIT license found in the
  * LICENSE file in the root directory of this source tree.
  *
- * @generated SignedSource<<3d98085a73dfc51541342dbb42ed89ab>>
+ * @generated SignedSource<<eb44aabe7e352481267aa9a6bf035ff1>>
  */
 
 /**
@@ -61,6 +61,7 @@ class ReactNativeFeatureFlagsAccessor {
   bool enableUIConsistency();
   bool enableViewRecycling();
   bool excludeYogaFromRawProps();
+  bool fixDifferentiatorEmittingUpdatesWithWrongParentTag();
   bool fixMappingOfEventPrioritiesBetweenFabricAndReact();
   bool fixMountingCoordinatorReportedPendingTransactionsOnAndroid();
   bool fuseboxEnabledDebug();
@@ -89,7 +90,7 @@ class ReactNativeFeatureFlagsAccessor {
   std::unique_ptr<ReactNativeFeatureFlagsProvider> currentProvider_;
   bool wasOverridden_;
 
-  std::array<std::atomic<const char*>, 46> accessedFeatureFlags_;
+  std::array<std::atomic<const char*>, 47> accessedFeatureFlags_;
 
   std::atomic<std::optional<bool>> commonTestFlag_;
   std::atomic<std::optional<bool>> completeReactInstanceCreationOnBgThreadOnAndroid_;
@@ -120,6 +121,7 @@ class ReactNativeFeatureFlagsAccessor {
   std::atomic<std::optional<bool>> enableUIConsistency_;
   std::atomic<std::optional<bool>> enableViewRecycling_;
   std::atomic<std::optional<bool>> excludeYogaFromRawProps_;
+  std::atomic<std::optional<bool>> fixDifferentiatorEmittingUpdatesWithWrongParentTag_;
   std::atomic<std::optional<bool>> fixMappingOfEventPrioritiesBetweenFabricAndReact_;
   std::atomic<std::optional<bool>> fixMountingCoordinatorReportedPendingTransactionsOnAndroid_;
   std::atomic<std::optional<bool>> fuseboxEnabledDebug_;

packages/react-native/ReactCommon/react/featureflags/ReactNativeFeatureFlagsDefaults.h

@@ -4,7 +4,7 @@
  * This source code is licensed under the MIT license found in the
  * LICENSE file in the root directory of this source tree.
  *
- * @generated SignedSource<<aff3c46b8d2db3bde519e1392569d53d>>
+ * @generated SignedSource<<ee899be30798eb6d386b44bc6bc027ea>>
  */
 
 /**
@@ -143,6 +143,10 @@ class ReactNativeFeatureFlagsDefaults : public ReactNativeFeatureFlagsProvider {
     return false;
   }
 
+  bool fixDifferentiatorEmittingUpdatesWithWrongParentTag() override {
+    return true;
+  }
+
   bool fixMappingOfEventPrioritiesBetweenFabricAndReact() override {
     return false;
   }

packages/react-native/ReactCommon/react/featureflags/ReactNativeFeatureFlagsProvider.h

@@ -4,7 +4,7 @@
  * This source code is licensed under the MIT license found in the
  * LICENSE file in the root directory of this source tree.
  *
- * @generated SignedSource<<8f8c7a372cdf9a3c06bc0d71f1ed85ad>>
+ * @generated SignedSource<<e5d1c60102f7444332bd34627c02eddd>>
  */
 
 /**
@@ -54,6 +54,7 @@ class ReactNativeFeatureFlagsProvider {
   virtual bool enableUIConsistency() = 0;
   virtual bool enableViewRecycling() = 0;
   virtual bool excludeYogaFromRawProps() = 0;
+  virtual bool fixDifferentiatorEmittingUpdatesWithWrongParentTag() = 0;
   virtual bool fixMappingOfEventPrioritiesBetweenFabricAndReact() = 0;
   virtual bool fixMountingCoordinatorReportedPendingTransactionsOnAndroid() = 0;
   virtual bool fuseboxEnabledDebug() = 0;

packages/react-native/ReactCommon/react/nativemodule/featureflags/NativeReactNativeFeatureFlags.cpp

@@ -4,7 +4,7 @@
  * This source code is licensed under the MIT license found in the
  * LICENSE file in the root directory of this source tree.
  *
- * @generated SignedSource<<4808c1455f8e17c42036055dd6a81d7d>>
+ * @generated SignedSource<<4055a9b5e34ff6740a99d4e08853fe7d>>
  */
 
 /**
@@ -189,6 +189,11 @@ bool NativeReactNativeFeatureFlags::excludeYogaFromRawProps(
   return ReactNativeFeatureFlags::excludeYogaFromRawProps();
 }
 
+bool NativeReactNativeFeatureFlags::fixDifferentiatorEmittingUpdatesWithWrongParentTag(
+    jsi::Runtime& /*runtime*/) {
+  return ReactNativeFeatureFlags::fixDifferentiatorEmittingUpdatesWithWrongParentTag();
+}
+
 bool NativeReactNativeFeatureFlags::fixMappingOfEventPrioritiesBetweenFabricAndReact(
     jsi::Runtime& /*runtime*/) {
   return ReactNativeFeatureFlags::fixMappingOfEventPrioritiesBetweenFabricAndReact();

packages/react-native/ReactCommon/react/nativemodule/featureflags/NativeReactNativeFeatureFlags.h

@@ -4,7 +4,7 @@
  * This source code is licensed under the MIT license found in the
  * LICENSE file in the root directory of this source tree.
  *
- * @generated SignedSource<<6b4909879b76908792d89e3f24c1453a>>
+ * @generated SignedSource<<9541abe6da92d991557ca6d2f1e36a9a>>
  */
 
 /**
@@ -95,6 +95,8 @@ class NativeReactNativeFeatureFlags
 
   bool excludeYogaFromRawProps(jsi::Runtime& runtime);
 
+  bool fixDifferentiatorEmittingUpdatesWithWrongParentTag(jsi::Runtime& runtime);
+
   bool fixMappingOfEventPrioritiesBetweenFabricAndReact(jsi::Runtime& runtime);
 
   bool fixMountingCoordinatorReportedPendingTransactionsOnAndroid(jsi::Runtime& runtime);

packages/react-native/ReactCommon/react/renderer/animations/LayoutAnimationKeyFrameManager.cpp

@@ -13,7 +13,7 @@
 
 #include <react/debug/flags.h>
 #include <react/debug/react_native_assert.h>
-
+#include <react/featureflags/ReactNativeFeatureFlags.h>
 #include <react/renderer/animations/conversions.h>
 #include <react/renderer/animations/utils.h>
 #include <react/renderer/components/image/ImageProps.h>
@@ -392,6 +392,14 @@ LayoutAnimationKeyFrameManager::pullTransaction(
                 if (keyframe.type == AnimationConfigurationType::Update &&
                     mutation.newChildShadowView.tag > 0) {
                   keyframe.viewPrev = mutation.newChildShadowView;
+                  if (ReactNativeFeatureFlags::
+                          fixDifferentiatorEmittingUpdatesWithWrongParentTag()) {
+                    keyframe.parentView = mutation.parentShadowView;
+                    react_native_assert(
+                        keyframe.finalMutationsForKeyFrame.size() == 1);
+                    keyframe.finalMutationsForKeyFrame[0].parentShadowView =
+                        mutation.parentShadowView;
+                  }
                 }
               }
             }

packages/react-native/ReactCommon/react/renderer/mounting/Differentiator.cpp

@@ -50,6 +50,33 @@ bool ShadowViewNodePair::operator!=(const ShadowViewNodePair& rhs) const {
   return !(*this == rhs);
 }
 
+#ifdef DEBUG_LOGS_DIFFER
+static std::ostream& operator<<(
+    std::ostream& out,
+    const ShadowViewNodePair& pair) {
+  out << pair.shadowNode->getTag();
+  if (!pair.isConcreteView) {
+    out << '\'';
+  }
+  if (pair.flattened) {
+    out << '*';
+  }
+  return out;
+}
+
+static std::ostream& operator<<(
+    std::ostream& out,
+    std::vector<ShadowViewNodePair*> vec) {
+  for (int i = 0; i < vec.size(); i++) {
+    if (i > 0) {
+      out << ", ";
+    }
+    out << *vec[i];
+  }
+  return out;
+}
+#endif
+
 /*
  * Extremely simple and naive implementation of a map.
  * The map is simple but it's optimized for particular constraints that we have
@@ -182,6 +209,21 @@ class TinyMap final {
   size_t erasedAtFront_{0};
 };
 
+#ifdef DEBUG_LOGS_DIFFER
+template <typename KeyT, typename ValueT>
+static std::ostream& operator<<(std::ostream& out, TinyMap<KeyT, ValueT>& map) {
+  auto it = map.begin();
+  if (it != map.end()) {
+    out << *it->second;
+    ++it;
+  }
+  for (; it != map.end(); ++it) {
+    out << ", " << *it->second;
+  }
+  return out;
+}
+#endif
+
 /*
  * Sorting comparator for `reorderInPlaceIfNeeded`.
  */
@@ -403,6 +445,7 @@ static void calculateShadowViewMutationsFlattener(
     const ShadowView& parentShadowView,
     TinyMap<Tag, ShadowViewNodePair*>& unvisitedOtherNodes,
     const ShadowViewNodePair& node,
+    const ShadowView& parentShadowViewForUpdate,
     TinyMap<Tag, ShadowViewNodePair*>* parentSubVisitedOtherNewNodes = nullptr,
     TinyMap<Tag, ShadowViewNodePair*>* parentSubVisitedOtherOldNodes = nullptr);
 
@@ -431,11 +474,10 @@ static void updateMatchedPairSubtrees(
   // We are either flattening or unflattening this node.
   if (oldPair.flattened != newPair.flattened) {
     DEBUG_LOGS({
-      LOG(ERROR)
-          << "Differ: flattening or unflattening in updateMatchedPairSubtrees: ["
-          << oldPair.shadowView.tag << "] [" << newPair.shadowView.tag << "] "
-          << oldPair.flattened << " " << newPair.flattened << " with parent: ["
-          << parentShadowView.tag << "]";
+      LOG(ERROR) << "Differ: "
+                 << (newPair.flattened ? "flattening" : "unflattening")
+                 << " in updateMatchedPairSubtrees: " << oldPair << " and "
+                 << newPair << " with parent [" << parentShadowView.tag << "]";
     });
 
     // Flattening
@@ -450,7 +492,8 @@ static void updateMatchedPairSubtrees(
           mutationContainer,
           parentShadowView,
           newRemainingPairs,
-          oldPair);
+          oldPair,
+          oldPair.shadowView);
     }
     // Unflattening
     else {
@@ -480,7 +523,8 @@ static void updateMatchedPairSubtrees(
           mutationContainer,
           parentShadowView,
           unvisitedOldChildPairs,
-          newPair);
+          newPair,
+          parentShadowView);
 
       // If old nodes were not visited, we know that we can delete
       // them now. They will be removed from the hierarchy by the
@@ -621,6 +665,10 @@ static void updateMatchedPair(
  *    performed in the subtree. If it *is* in the map, it means the node is not
  *    in the Tree, and should be Deleted/Created  **after this function is
  *    called**, by the caller.
+ *
+ * @param parentShadowView shadowView under which nodes should be mounted
+ * @param parentShadowViewForUpdate current parent in which node is mounted,
+ *    used for update mutations
  */
 static void calculateShadowViewMutationsFlattener(
     ViewNodePairScope& scope,
@@ -629,44 +677,20 @@ static void calculateShadowViewMutationsFlattener(
     const ShadowView& parentShadowView,
     TinyMap<Tag, ShadowViewNodePair*>& unvisitedOtherNodes,
     const ShadowViewNodePair& node,
+    const ShadowView& parentShadowViewForUpdate,
     TinyMap<Tag, ShadowViewNodePair*>* parentSubVisitedOtherNewNodes,
     TinyMap<Tag, ShadowViewNodePair*>* parentSubVisitedOtherOldNodes) {
-  DEBUG_LOGS({
-    LOG(ERROR) << "Differ Flattener 1: "
-               << (reparentMode == ReparentMode::Unflatten ? "Unflattening"
-                                                           : "Flattening")
-               << " [" << node.shadowView.tag << "]";
-  });
-
   // Step 1: iterate through entire tree
   std::vector<ShadowViewNodePair*> treeChildren =
       sliceChildShadowNodeViewPairsFromViewNodePair(node, scope);
 
   DEBUG_LOGS({
-    LOG(ERROR) << "Differ Flattener 1.4: "
+    LOG(ERROR) << "Differ Flattener: "
                << (reparentMode == ReparentMode::Unflatten ? "Unflattening"
                                                            : "Flattening")
                << " [" << node.shadowView.tag << "]";
-    LOG(ERROR) << "Differ Flattener Entry: Child Pairs: ";
-    std::string strTreeChildPairs;
-    for (size_t k = 0; k < treeChildren.size(); k++) {
-      strTreeChildPairs.append(std::to_string(treeChildren[k]->shadowView.tag));
-      strTreeChildPairs.append(treeChildren[k]->isConcreteView ? "" : "'");
-      strTreeChildPairs.append(treeChildren[k]->flattened ? "*" : "");
-      strTreeChildPairs.append(", ");
-    }
-    std::string strListChildPairs;
-    for (auto& unvisitedNode : unvisitedOtherNodes) {
-      strListChildPairs.append(
-          std::to_string(unvisitedNode.second->shadowView.tag));
-      strListChildPairs.append(unvisitedNode.second->isConcreteView ? "" : "'");
-      strListChildPairs.append(unvisitedNode.second->flattened ? "*" : "");
-      strListChildPairs.append(", ");
-    }
-    LOG(ERROR) << "Differ Flattener Entry: Tree Child Pairs: "
-               << strTreeChildPairs;
-    LOG(ERROR) << "Differ Flattener Entry: List Child Pairs: "
-               << strListChildPairs;
+    LOG(ERROR) << "> Tree Child Pairs: " << treeChildren;
+    LOG(ERROR) << "> List Child Pairs: " << unvisitedOtherNodes;
   });
 
   // Views in other tree that are visited by sub-flattening or
@@ -838,11 +862,18 @@ static void calculateShadowViewMutationsFlattener(
       // ShadowNode.
       if (newTreeNodePair.shadowView != oldTreeNodePair.shadowView &&
           newTreeNodePair.isConcreteView && oldTreeNodePair.isConcreteView) {
+        // We execute updates before creates, so pass the current parent in when
+        // unflattening.
+        // TODO: whenever we insert, we already update the relevant properties,
+        // so this update is redundant. We should remove this.
         mutationContainer.updateMutations.push_back(
             ShadowViewMutation::UpdateMutation(
                 oldTreeNodePair.shadowView,
                 newTreeNodePair.shadowView,
-                node.shadowView));
+                ReactNativeFeatureFlags::
+                        fixDifferentiatorEmittingUpdatesWithWrongParentTag()
+                    ? parentShadowViewForUpdate
+                    : node.shadowView));
       }
 
       // Update children if appropriate.
@@ -877,6 +908,9 @@ static void calculateShadowViewMutationsFlattener(
                    : newTreeNodePair.shadowView),
               unvisitedOtherNodes,
               treeChildPair,
+              (reparentMode == ReparentMode::Flatten
+                   ? oldTreeNodePair.shadowView
+                   : parentShadowView),
               subVisitedNewMap,
               subVisitedOldMap);
         } else {
@@ -918,6 +952,9 @@ static void calculateShadowViewMutationsFlattener(
                      : newTreeNodePair.shadowView),
                 unvisitedRecursiveChildPairs,
                 oldTreeNodePair,
+                (reparentMode == ReparentMode::Flatten
+                     ? oldTreeNodePair.shadowView
+                     : parentShadowView),
                 subVisitedNewMap,
                 subVisitedOldMap);
           }
@@ -933,6 +970,9 @@ static void calculateShadowViewMutationsFlattener(
                      : newTreeNodePair.shadowView),
                 unvisitedRecursiveChildPairs,
                 newTreeNodePair,
+                (reparentMode == ReparentMode::Flatten
+                     ? oldTreeNodePair.shadowView
+                     : parentShadowView),
                 subVisitedNewMap,
                 subVisitedOldMap);
 
@@ -1069,26 +1109,8 @@ static void calculateShadowViewMutations(
   DEBUG_LOGS({
     LOG(ERROR) << "Differ Entry: Child Pairs of node: [" << parentShadowView.tag
                << "]";
-    std::string strOldChildPairs;
-    for (size_t oldIndex = 0; oldIndex < oldChildPairs.size(); oldIndex++) {
-      strOldChildPairs.append(
-          std::to_string(oldChildPairs[oldIndex]->shadowView.tag));
-      strOldChildPairs.append(
-          oldChildPairs[oldIndex]->isConcreteView ? "" : "'");
-      strOldChildPairs.append(oldChildPairs[oldIndex]->flattened ? "*" : "");
-      strOldChildPairs.append(", ");
-    }
-    std::string strNewChildPairs;
-    for (size_t newIndex = 0; newIndex < newChildPairs.size(); newIndex++) {
-      strNewChildPairs.append(
-          std::to_string(newChildPairs[newIndex]->shadowView.tag));
-      strNewChildPairs.append(
-          newChildPairs[newIndex]->isConcreteView ? "" : "'");
-      strNewChildPairs.append(newChildPairs[newIndex]->flattened ? "*" : "");
-      strNewChildPairs.append(", ");
-    }
-    LOG(ERROR) << "Differ Entry: Old Child Pairs: " << strOldChildPairs;
-    LOG(ERROR) << "Differ Entry: New Child Pairs: " << strNewChildPairs;
+    LOG(ERROR) << "> Old Child Pairs: " << oldChildPairs;
+    LOG(ERROR) << "> New Child Pairs: " << newChildPairs;
   });
 
   // Stage 1: Collecting `Update` mutations
@@ -1117,14 +1139,9 @@ static void calculateShadowViewMutations(
     }
 
     DEBUG_LOGS({
-      LOG(ERROR) << "Differ Branch 1.2: Same tags, update and recurse: ["
-                 << oldChildPair.shadowView.tag << "]"
-                 << (oldChildPair.flattened ? " (flattened)" : "")
-                 << (oldChildPair.isConcreteView ? " (concrete)" : "") << "["
-                 << newChildPair.shadowView.tag << "]"
-                 << (newChildPair.flattened ? " (flattened)" : "")
-                 << (newChildPair.isConcreteView ? " (concrete)" : "")
-                 << " with parent: [" << parentShadowView.tag << "]";
+      LOG(ERROR) << "Differ Branch 1.2: Same tags, update and recurse: "
+                 << oldChildPair << " and " << newChildPair << " with parent: ["
+                 << parentShadowView.tag << "]";
     });
 
     if (newChildPair.isConcreteView &&
@@ -1165,9 +1182,8 @@ static void calculateShadowViewMutations(
       const auto& oldChildPair = *oldChildPairs[index];
 
       DEBUG_LOGS({
-        LOG(ERROR) << "Differ Branch 2: Deleting Tag/Tree: ["
-                   << oldChildPair.shadowView.tag << "]" << " with parent: ["
-                   << parentShadowView.tag << "]";
+        LOG(ERROR) << "Differ Branch 2: Deleting Tag/Tree: " << oldChildPair
+                   << " with parent: [" << parentShadowView.tag << "]";
       });
 
       if (!oldChildPair.isConcreteView) {
@@ -1200,9 +1216,8 @@ static void calculateShadowViewMutations(
       const auto& newChildPair = *newChildPairs[index];
 
       DEBUG_LOGS({
-        LOG(ERROR) << "Differ Branch 3: Creating Tag/Tree: ["
-                   << newChildPair.shadowView.tag << "]" << " with parent: ["
-                   << parentShadowView.tag << "]";
+        LOG(ERROR) << "Differ Branch 3: Creating Tag/Tree: " << newChildPair
+                   << " with parent: [" << parentShadowView.tag << "]";
       });
 
       if (!newChildPair.isConcreteView) {
@@ -1257,14 +1272,9 @@ static void calculateShadowViewMutations(
 
         if (newTag == oldTag) {
           DEBUG_LOGS({
-            LOG(ERROR) << "Differ Branch 5: Matched Tags at indices: "
-                       << oldIndex << " " << newIndex << ": ["
-                       << oldChildPair.shadowView.tag << "]"
-                       << (oldChildPair.flattened ? "(flattened)" : "")
-                       << (oldChildPair.isConcreteView ? "(concrete)" : "")
-                       << " [" << newChildPair.shadowView.tag << "]"
-                       << (newChildPair.flattened ? "(flattened)" : "")
-                       << (newChildPair.isConcreteView ? "(concrete)" : "")
+            LOG(ERROR) << "Differ Branch 4: Matched Tags at indices: "
+                       << oldIndex << " and " << newIndex << ": "
+                       << oldChildPair << " and " << newChildPair
                        << " with parent: [" << parentShadowView.tag << "]";
           });
 
@@ -1306,6 +1316,13 @@ static void calculateShadowViewMutations(
         if (insertedIt != newInsertedPairs.end()) {
           const auto& newChildPair = *insertedIt->second;
 
+          DEBUG_LOGS({
+            LOG(ERROR) << "Differ Branch 5: Founded reordered tags at indices: "
+                       << oldIndex << ": " << oldChildPair << " and "
+                       << newChildPair << " with parent: ["
+                       << parentShadowView.tag << "]";
+          });
+
           updateMatchedPair(
               mutationContainer,
               true,
@@ -1345,13 +1362,10 @@ static void calculateShadowViewMutations(
 
           DEBUG_LOGS({
             LOG(ERROR)
-                << "Differ Branch 9: Removing tag that was not reinserted: "
-                << oldIndex << ": [" << oldChildPair.shadowView.tag << "]"
-                << (oldChildPair.flattened ? " (flattened)" : "")
-                << (oldChildPair.isConcreteView ? " (concrete)" : "")
-                << " with parent: [" << parentShadowView.tag << "] "
-                << "node is in other tree? "
-                << (oldChildPair.inOtherTree() ? "yes" : "no");
+                << "Differ Branch 6: Removing tag that was not re-inserted: "
+                << oldChildPair << " with parent: [" << parentShadowView.tag
+                << "], which is " << (oldChildPair.inOtherTree() ? "" : "not ")
+                << "in other tree";
           });
 
           // Edge case: node is not found in `newRemainingPairs`, due to
@@ -1398,11 +1412,8 @@ static void calculateShadowViewMutations(
       auto& newChildPair = *newChildPairs[newIndex];
       DEBUG_LOGS({
         LOG(ERROR)
-            << "Differ Branch 10: Inserting tag/tree that was not (yet?) removed from hierarchy: "
-            << newIndex << "/" << newSize << ": ["
-            << newChildPair.shadowView.tag << "]"
-            << (newChildPair.flattened ? " (flattened)" : "")
-            << (newChildPair.isConcreteView ? " (concrete)" : "")
+            << "Differ Branch 7: Inserting tag/tree that was not (yet?) removed from hierarchy: "
+            << newChildPair << " @ " << newIndex << "/" << newSize
             << " with parent: [" << parentShadowView.tag << "]";
       });
       if (newChildPair.isConcreteView) {
@@ -1438,10 +1449,8 @@ static void calculateShadowViewMutations(
 
       DEBUG_LOGS({
         LOG(ERROR)
-            << "Differ Branch 11: Deleting tag/tree that was not in new hierarchy: "
-            << "[" << oldChildPair.shadowView.tag << "]"
-            << (oldChildPair.flattened ? "(flattened)" : "")
-            << (oldChildPair.isConcreteView ? "(concrete)" : "")
+            << "Differ Branch 8: Deleting tag/tree that was not in new hierarchy: "
+            << oldChildPair
             << (oldChildPair.inOtherTree() ? "(in other tree)" : "")
             << " with parent: [" << parentShadowView.tag << "] ##"
             << std::hash<ShadowView>{}(oldChildPair.shadowView);
@@ -1480,10 +1489,8 @@ static void calculateShadowViewMutations(
 
       DEBUG_LOGS({
         LOG(ERROR)
-            << "Differ Branch 12: Inserting tag/tree that was not in old hierarchy: "
-            << "[" << newChildPair.shadowView.tag << "]"
-            << (newChildPair.flattened ? "(flattened)" : "")
-            << (newChildPair.isConcreteView ? "(concrete)" : "")
+            << "Differ Branch 9: Inserting tag/tree that was not in old hierarchy: "
+            << newChildPair
             << (newChildPair.inOtherTree() ? "(in other tree)" : "")
             << " with parent: [" << parentShadowView.tag << "]";
       });
@@ -1575,6 +1582,40 @@ ShadowViewMutation::List calculateShadowViewMutations(
           ShadowViewNodePair{.shadowNode = &newRootShadowNode},
           viewNodePairScope));
 
+  DEBUG_LOGS({
+    LOG(ERROR) << "Differ Completed: " << mutations.size() << " mutations";
+    for (size_t i = 0; i < mutations.size(); i++) {
+      auto& mutation = mutations[i];
+      switch (mutation.type) {
+        case ShadowViewMutation::Type::Create:
+          LOG(ERROR) << "[" << i << "] CREATE "
+                     << mutation.newChildShadowView.tag;
+          break;
+        case ShadowViewMutation::Type::Delete:
+          LOG(ERROR) << "[" << i << "] DELETE "
+                     << mutation.oldChildShadowView.tag;
+          break;
+        case ShadowViewMutation::Type::Insert:
+          LOG(ERROR) << "[" << i << "] INSERT "
+                     << mutation.newChildShadowView.tag << " INTO "
+                     << mutation.parentShadowView.tag << " @ "
+                     << mutation.index;
+          break;
+        case ShadowViewMutation::Type::Remove:
+          LOG(ERROR) << "[" << i << "] REMOVE "
+                     << mutation.oldChildShadowView.tag << " FROM "
+                     << mutation.parentShadowView.tag << " @ "
+                     << mutation.index;
+          break;
+        case ShadowViewMutation::Type::Update:
+          LOG(ERROR) << "[" << i << "] UPDATE "
+                     << mutation.newChildShadowView.tag << " IN "
+                     << mutation.parentShadowView.tag;
+          break;
+      }
+    }
+  });
+
   return mutations;
 }
 

packages/react-native/ReactCommon/react/renderer/mounting/stubs/StubViewTree.cpp

@@ -221,6 +221,11 @@ void StubViewTree::mutate(const ShadowViewMutationList& mutations) {
         react_native_assert(hasTag(mutation.newChildShadowView.tag));
         auto oldStubView = registry_[mutation.newChildShadowView.tag];
         react_native_assert(oldStubView->tag != 0);
+        if (mutation.parentShadowView.tag != 0) {
+          react_native_assert(hasTag(mutation.parentShadowView.tag));
+          react_native_assert(
+              oldStubView->parentTag == mutation.parentShadowView.tag);
+        }
         if ((ShadowView)(*oldStubView) != mutation.oldChildShadowView) {
           LOG(ERROR)
               << "StubView: ASSERT FAILURE: UPDATE mutation assertion failure: oldChildShadowView does not match oldStubView: ["

packages/react-native/ReactCommon/react/renderer/mounting/tests/MountingTest.cpp

@@ -558,8 +558,7 @@ TEST(MountingTest, testViewReparentingInstructionGeneration) {
   EXPECT_EQ(mutations1[0].oldChildShadowView.tag, childG->getTag());
   EXPECT_EQ(mutations1[1].type, ShadowViewMutation::Update);
   EXPECT_EQ(mutations1[1].oldChildShadowView.tag, reparentedViewA->getTag());
-  // This is incorrect! ChildH does not exist yet at this point
-  EXPECT_EQ(mutations1[1].parentShadowView.tag, childH->getTag());
+  EXPECT_EQ(mutations1[1].parentShadowView.tag, childG->getTag());
   EXPECT_EQ(mutations1[2].type, ShadowViewMutation::Remove);
   EXPECT_EQ(mutations1[2].oldChildShadowView.tag, reparentedViewA->getTag());
   EXPECT_EQ(mutations1[3].type, ShadowViewMutation::Create);

packages/react-native/scripts/featureflags/ReactNativeFeatureFlags.config.js

@@ -292,6 +292,14 @@ const definitions: FeatureFlagDefinitions = {
         purpose: 'experimentation',
       },
     },
+    fixDifferentiatorEmittingUpdatesWithWrongParentTag: {
+      defaultValue: true,
+      metadata: {
+        description:
+          "Fixes a bug in Differentiator where parent views may be referenced before they're created",
+        purpose: 'release',
+      },
+    },
     fixMappingOfEventPrioritiesBetweenFabricAndReact: {
       defaultValue: false,
       metadata: {

packages/react-native/src/private/featureflags/ReactNativeFeatureFlags.js

@@ -4,7 +4,7 @@
  * This source code is licensed under the MIT license found in the
  * LICENSE file in the root directory of this source tree.
  *
- * @generated SignedSource<<38ad29621eeb29a9f82735dc187c13d4>>
+ * @generated SignedSource<<ceb682684f8c9df33a3f432033ab266a>>
  * @flow strict
  */
 
@@ -80,6 +80,7 @@ export type ReactNativeFeatureFlags = {
   enableUIConsistency: Getter<boolean>,
   enableViewRecycling: Getter<boolean>,
   excludeYogaFromRawProps: Getter<boolean>,
+  fixDifferentiatorEmittingUpdatesWithWrongParentTag: Getter<boolean>,
   fixMappingOfEventPrioritiesBetweenFabricAndReact: Getter<boolean>,
   fixMountingCoordinatorReportedPendingTransactionsOnAndroid: Getter<boolean>,
   fuseboxEnabledDebug: Getter<boolean>,
@@ -304,6 +305,10 @@ export const enableViewRecycling: Getter<boolean> = createNativeFlagGetter('enab
  * When enabled, rawProps in Props will not include Yoga specific props.
  */
 export const excludeYogaFromRawProps: Getter<boolean> = createNativeFlagGetter('excludeYogaFromRawProps', false);
+/**
+ * Fixes a bug in Differentiator where parent views may be referenced before they're created
+ */
+export const fixDifferentiatorEmittingUpdatesWithWrongParentTag: Getter<boolean> = createNativeFlagGetter('fixDifferentiatorEmittingUpdatesWithWrongParentTag', true);
 /**
  * Uses the default event priority instead of the discreet event priority by default when dispatching events from Fabric to React.
  */

packages/react-native/src/private/featureflags/specs/NativeReactNativeFeatureFlags.js

@@ -4,7 +4,7 @@
  * This source code is licensed under the MIT license found in the
  * LICENSE file in the root directory of this source tree.
  *
- * @generated SignedSource<<17c0e677f7b308795e836c558b15d1d1>>
+ * @generated SignedSource<<b36732a4a633b239ebd6d12d1ef460cb>>
  * @flow strict
  */
 
@@ -53,6 +53,7 @@ export interface Spec extends TurboModule {
   +enableUIConsistency?: () => boolean;
   +enableViewRecycling?: () => boolean;
   +excludeYogaFromRawProps?: () => boolean;
+  +fixDifferentiatorEmittingUpdatesWithWrongParentTag?: () => boolean;
   +fixMappingOfEventPrioritiesBetweenFabricAndReact?: () => boolean;
   +fixMountingCoordinatorReportedPendingTransactionsOnAndroid?: () => boolean;
   +fuseboxEnabledDebug?: () => boolean;

scripts/release-testing/test-e2e-local.js

@@ -300,10 +300,9 @@ async function testRNTestProject(
     'reactNativeArchitectures=arm64-v8a',
     'android/gradle.properties',
   );
-  const hermesEnabled = (await argv).hermes === true;
 
   // Update gradle properties to set Hermes as false
-  if (!hermesEnabled) {
+  if (argv.hermes == null) {
     sed(
       '-i',
       'hermesEnabled=true',
@@ -318,7 +317,7 @@ async function testRNTestProject(
     exec('bundle install');
     exec(
       `HERMES_ENGINE_TARBALL_PATH=${hermesPath} USE_HERMES=${
-        hermesEnabled ? 1 : 0
+        argv.hermes === true ? 1 : 0
       } bundle exec pod install --ansi`,
     );
 

scripts/release-testing/utils/github-actions-utils.js

@@ -11,6 +11,7 @@
 
 'use strict';
 
+const chalk = require('chalk');
 const {execSync: exec} = require('child_process');
 const fetch = require('node-fetch');
 
@@ -30,6 +31,18 @@ type WorkflowRun = {
   url: string,
   created_at: string,
   conclusion: "success" | "failure" | "neutral" | "cancelled" | "skipped" | "timed_out" | "action_required" | null,
+  head_commit: {
+    author: {
+      name: string,
+    },
+    message: string,
+    ...
+  };
+  triggering_actor: {
+    login: string,
+    ...
+  };
+  run_started_at: string,
 };
 
 
@@ -102,6 +115,13 @@ async function _getArtifacts(run_id /*: number */) /*: Promise<Artifacts> */ {
   return body;
 }
 
+function quote(text /*: string*/, prefix /*: string */ = ' > ') {
+  return text
+    .split('\n')
+    .map(line => prefix + line)
+    .join('\n');
+}
+
 // === Public Interface === //
 async function initialize(
   ciToken /*: string */,
@@ -149,6 +169,21 @@ async function initialize(
       ) ?? workflow;
   }
 
+  const commit = workflow.head_commit;
+  const hours =
+    (new Date().getTime() - new Date(workflow.run_started_at).getTime()) /
+    (60 * 60 * 1000);
+  const started_by = workflow.triggering_actor.login;
+
+  console.log(
+    chalk.green(`The artifact being used is from a workflow started ${chalk.bold.magentaBright(hours.toFixed(0))} hours ago by ${chalk.bold.magentaBright(started_by)}:
+
+Author: ${chalk.bold(commit.author.name)}
+Message:
+${chalk.magentaBright(quote(commit.message))}
+  `),
+  );
+
   artifacts = await _getArtifacts(workflow.id);
 }