Migrate enableEagerRootViewAttachment to ReactNativeFeatureFlags (#45604

)

Summary:
Pull Request resolved: #45604

Migrate enableEagerRootViewAttachment to ReactNativeFeatureFlags

changelog: [internal] internal

Reviewed By: NickGerleman

Differential Revision: D60022934

packages/react-native/ReactAndroid/api/ReactAndroid.api

@@ -1965,7 +1965,6 @@ public class com/facebook/react/config/ReactFeatureFlags {
 	public static field dispatchPointerEvents Z
 	public static field enableBridgelessArchitecture Z
 	public static field enableCppPropsIteratorSetter Z
-	public static field enableEagerRootViewAttachment Z
 	public static field enableFabricLogs Z
 	public static field enableFabricRenderer Z
 	public static field enableViewRecycling Z

packages/react-native/ReactAndroid/src/main/java/com/facebook/react/ReactRootView.java

@@ -49,6 +49,7 @@
 import com.facebook.react.bridge.WritableNativeMap;
 import com.facebook.react.common.annotations.VisibleForTesting;
 import com.facebook.react.config.ReactFeatureFlags;
+import com.facebook.react.internal.featureflags.ReactNativeFeatureFlags;
 import com.facebook.react.modules.appregistry.AppRegistry;
 import com.facebook.react.modules.deviceinfo.DeviceInfoModule;
 import com.facebook.react.uimanager.DisplayMetricsHolder;
@@ -478,7 +479,7 @@ public void startReactApplication(
       mReactInstanceManager.createReactContextInBackground();
       // if in this experiment, we initialize the root earlier in startReactApplication
       // instead of waiting for the initial measure
-      if (ReactFeatureFlags.enableEagerRootViewAttachment) {
+      if (ReactNativeFeatureFlags.enableEagerRootViewAttachment()) {
         if (!mWasMeasured) {
           // Ideally, those values will be used by default, but we only update them here to scope
           // this change to `enableEagerRootViewAttachment` experiment.

packages/react-native/ReactAndroid/src/main/java/com/facebook/react/config/ReactFeatureFlags.java

@@ -61,9 +61,6 @@ public class ReactFeatureFlags {
   /** This feature flag enables logs for Fabric */
   public static boolean enableFabricLogs = false;
 
-  /** Feature flag to configure eager attachment of the root view/initialisation of the JS code */
-  public static boolean enableEagerRootViewAttachment = false;
-
   public static boolean dispatchPointerEvents = false;
 
   /**

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<<ca939ab47fa68fbb5acf5ea34481def9>>
+ * @generated SignedSource<<fe2b592db8339808bf8ab727594ec6e0>>
  */
 
 /**
@@ -82,6 +82,12 @@ public object ReactNativeFeatureFlags {
   @JvmStatic
   public fun enableCleanTextInputYogaNode(): Boolean = accessor.enableCleanTextInputYogaNode()
 
+  /**
+   * Feature flag to configure eager attachment of the root view/initialisation of the JS code.
+   */
+  @JvmStatic
+  public fun enableEagerRootViewAttachment(): Boolean = accessor.enableEagerRootViewAttachment()
+
   /**
    * When the app is completely migrated to Fabric, set this flag to true to disable parts of Paper infrastructure that are not needed anymore but consume memory and CPU. Specifically, UIViewOperationQueue and EventDispatcherImpl will no longer work as they will not subscribe to ReactChoreographer for updates.
    */

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<<2a8d5ca8a0ac46b4d3177cb8b12ad7ac>>
+ * @generated SignedSource<<0341c3c0f1eb484c305ee8732d6fd26f>>
  */
 
 /**
@@ -29,6 +29,7 @@ public class ReactNativeFeatureFlagsCxxAccessor : ReactNativeFeatureFlagsAccesso
   private var destroyFabricSurfacesInReactInstanceManagerCache: Boolean? = null
   private var enableAlignItemsBaselineOnFabricIOSCache: Boolean? = null
   private var enableCleanTextInputYogaNodeCache: Boolean? = null
+  private var enableEagerRootViewAttachmentCache: Boolean? = null
   private var enableFabricRendererExclusivelyCache: Boolean? = null
   private var enableGranularShadowTreeStateReconciliationCache: Boolean? = null
   private var enableLongTaskAPICache: Boolean? = null
@@ -139,6 +140,15 @@ public class ReactNativeFeatureFlagsCxxAccessor : ReactNativeFeatureFlagsAccesso
     return cached
   }
 
+  override fun enableEagerRootViewAttachment(): Boolean {
+    var cached = enableEagerRootViewAttachmentCache
+    if (cached == null) {
+      cached = ReactNativeFeatureFlagsCxxInterop.enableEagerRootViewAttachment()
+      enableEagerRootViewAttachmentCache = cached
+    }
+    return cached
+  }
+
   override fun enableFabricRendererExclusively(): Boolean {
     var cached = enableFabricRendererExclusivelyCache
     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<<aaf205098eaac9171aa15bc8f7bda805>>
+ * @generated SignedSource<<82a0b829cbc75d864dba1ae4c65b2036>>
  */
 
 /**
@@ -46,6 +46,8 @@ public object ReactNativeFeatureFlagsCxxInterop {
 
   @DoNotStrip @JvmStatic public external fun enableCleanTextInputYogaNode(): Boolean
 
+  @DoNotStrip @JvmStatic public external fun enableEagerRootViewAttachment(): Boolean
+
   @DoNotStrip @JvmStatic public external fun enableFabricRendererExclusively(): Boolean
 
   @DoNotStrip @JvmStatic public external fun enableGranularShadowTreeStateReconciliation(): 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<<abdee8d0b85b0d9940207b9cbe6d3f78>>
+ * @generated SignedSource<<7a16361098f54ac7a114d511fce10825>>
  */
 
 /**
@@ -41,6 +41,8 @@ public open class ReactNativeFeatureFlagsDefaults : ReactNativeFeatureFlagsProvi
 
   override fun enableCleanTextInputYogaNode(): Boolean = false
 
+  override fun enableEagerRootViewAttachment(): Boolean = false
+
   override fun enableFabricRendererExclusively(): Boolean = false
 
   override fun enableGranularShadowTreeStateReconciliation(): 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<<82f6d4eda4011bee81810af366f5d677>>
+ * @generated SignedSource<<833b024aec14737d59abd02092fcfa11>>
  */
 
 /**
@@ -33,6 +33,7 @@ public class ReactNativeFeatureFlagsLocalAccessor : ReactNativeFeatureFlagsAcces
   private var destroyFabricSurfacesInReactInstanceManagerCache: Boolean? = null
   private var enableAlignItemsBaselineOnFabricIOSCache: Boolean? = null
   private var enableCleanTextInputYogaNodeCache: Boolean? = null
+  private var enableEagerRootViewAttachmentCache: Boolean? = null
   private var enableFabricRendererExclusivelyCache: Boolean? = null
   private var enableGranularShadowTreeStateReconciliationCache: Boolean? = null
   private var enableLongTaskAPICache: Boolean? = null
@@ -152,6 +153,16 @@ public class ReactNativeFeatureFlagsLocalAccessor : ReactNativeFeatureFlagsAcces
     return cached
   }
 
+  override fun enableEagerRootViewAttachment(): Boolean {
+    var cached = enableEagerRootViewAttachmentCache
+    if (cached == null) {
+      cached = currentProvider.enableEagerRootViewAttachment()
+      accessedFeatureFlags.add("enableEagerRootViewAttachment")
+      enableEagerRootViewAttachmentCache = cached
+    }
+    return cached
+  }
+
   override fun enableFabricRendererExclusively(): Boolean {
     var cached = enableFabricRendererExclusivelyCache
     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<<ece587d5e6643fb906cfee816824f224>>
+ * @generated SignedSource<<69c396cad1d473c5793df517fa183f95>>
  */
 
 /**
@@ -41,6 +41,8 @@ public interface ReactNativeFeatureFlagsProvider {
 
   @DoNotStrip public fun enableCleanTextInputYogaNode(): Boolean
 
+  @DoNotStrip public fun enableEagerRootViewAttachment(): Boolean
+
   @DoNotStrip public fun enableFabricRendererExclusively(): Boolean
 
   @DoNotStrip public fun enableGranularShadowTreeStateReconciliation(): Boolean

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<<7c14f956fd20226acfb532d806c6eb7a>>
+ * @generated SignedSource<<e1a5c4bfa72b16c95464432e449b4ba8>>
  */
 
 /**
@@ -93,6 +93,12 @@ class ReactNativeFeatureFlagsProviderHolder
     return method(javaProvider_);
   }
 
+  bool enableEagerRootViewAttachment() override {
+    static const auto method =
+        getReactNativeFeatureFlagsProviderJavaClass()->getMethod<jboolean()>("enableEagerRootViewAttachment");
+    return method(javaProvider_);
+  }
+
   bool enableFabricRendererExclusively() override {
     static const auto method =
         getReactNativeFeatureFlagsProviderJavaClass()->getMethod<jboolean()>("enableFabricRendererExclusively");
@@ -310,6 +316,11 @@ bool JReactNativeFeatureFlagsCxxInterop::enableCleanTextInputYogaNode(
   return ReactNativeFeatureFlags::enableCleanTextInputYogaNode();
 }
 
+bool JReactNativeFeatureFlagsCxxInterop::enableEagerRootViewAttachment(
+    facebook::jni::alias_ref<JReactNativeFeatureFlagsCxxInterop> /*unused*/) {
+  return ReactNativeFeatureFlags::enableEagerRootViewAttachment();
+}
+
 bool JReactNativeFeatureFlagsCxxInterop::enableFabricRendererExclusively(
     facebook::jni::alias_ref<JReactNativeFeatureFlagsCxxInterop> /*unused*/) {
   return ReactNativeFeatureFlags::enableFabricRendererExclusively();
@@ -494,6 +505,9 @@ void JReactNativeFeatureFlagsCxxInterop::registerNatives() {
       makeNativeMethod(
         "enableCleanTextInputYogaNode",
         JReactNativeFeatureFlagsCxxInterop::enableCleanTextInputYogaNode),
+      makeNativeMethod(
+        "enableEagerRootViewAttachment",
+        JReactNativeFeatureFlagsCxxInterop::enableEagerRootViewAttachment),
       makeNativeMethod(
         "enableFabricRendererExclusively",
         JReactNativeFeatureFlagsCxxInterop::enableFabricRendererExclusively),

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<<f06779455d65f78f561eaca745262a99>>
+ * @generated SignedSource<<1722d711f77b3f47cc3c665fce026b5a>>
  */
 
 /**
@@ -57,6 +57,9 @@ class JReactNativeFeatureFlagsCxxInterop
   static bool enableCleanTextInputYogaNode(
     facebook::jni::alias_ref<JReactNativeFeatureFlagsCxxInterop>);
 
+  static bool enableEagerRootViewAttachment(
+    facebook::jni::alias_ref<JReactNativeFeatureFlagsCxxInterop>);
+
   static bool enableFabricRendererExclusively(
     facebook::jni::alias_ref<JReactNativeFeatureFlagsCxxInterop>);
 

packages/react-native/ReactAndroid/src/test/java/com/facebook/react/RootViewTest.kt

@@ -24,6 +24,7 @@ import com.facebook.react.bridge.ReactTestHelper
 import com.facebook.react.bridge.WritableArray
 import com.facebook.react.bridge.WritableMap
 import com.facebook.react.common.SystemClock
+import com.facebook.react.internal.featureflags.ReactNativeFeatureFlags
 import com.facebook.react.uimanager.DisplayMetricsHolder
 import com.facebook.react.uimanager.UIManagerModule
 import com.facebook.react.uimanager.events.Event
@@ -54,8 +55,16 @@ class RootViewTest {
   private lateinit var arguments: MockedStatic<Arguments>
   private lateinit var systemClock: MockedStatic<SystemClock>
 
+  private lateinit var featureFlags: MockedStatic<ReactNativeFeatureFlags>
+
   @Before
   fun setUp() {
+    // Avoid trying to load ReactNativeFeatureFlags JNI library
+    featureFlags = mockStatic(ReactNativeFeatureFlags::class.java)
+    featureFlags
+        .`when`<Boolean> { ReactNativeFeatureFlags.enableEagerRootViewAttachment() }
+        .thenAnswer { false }
+
     arguments = Mockito.mockStatic(Arguments::class.java)
     arguments.`when`<WritableArray> { Arguments.createArray() }.thenAnswer { JavaOnlyArray() }
     arguments.`when`<WritableMap> { Arguments.createMap() }.thenAnswer { JavaOnlyMap() }
@@ -78,6 +87,7 @@ class RootViewTest {
   fun tearDown() {
     systemClock.close()
     arguments.close()
+    featureFlags.close()
   }
 
   @Test

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<<bab53ba585938b3bf458dbe0874931f8>>
+ * @generated SignedSource<<459682475d0fcefcdfce6ebeb7d1db19>>
  */
 
 /**
@@ -57,6 +57,10 @@ bool ReactNativeFeatureFlags::enableCleanTextInputYogaNode() {
   return getAccessor().enableCleanTextInputYogaNode();
 }
 
+bool ReactNativeFeatureFlags::enableEagerRootViewAttachment() {
+  return getAccessor().enableEagerRootViewAttachment();
+}
+
 bool ReactNativeFeatureFlags::enableFabricRendererExclusively() {
   return getAccessor().enableFabricRendererExclusively();
 }

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<<55d6c0f7ab8abe8411194235ab362cd2>>
+ * @generated SignedSource<<83a6879d27dd7dbcb181f30c3b6f0225>>
  */
 
 /**
@@ -82,6 +82,11 @@ class ReactNativeFeatureFlags {
    */
   RN_EXPORT static bool enableCleanTextInputYogaNode();
 
+  /**
+   * Feature flag to configure eager attachment of the root view/initialisation of the JS code.
+   */
+  RN_EXPORT static bool enableEagerRootViewAttachment();
+
   /**
    * When the app is completely migrated to Fabric, set this flag to true to disable parts of Paper infrastructure that are not needed anymore but consume memory and CPU. Specifically, UIViewOperationQueue and EventDispatcherImpl will no longer work as they will not subscribe to ReactChoreographer for updates.
    */