Remove Hermes V1 opt-out mechanism for Android

build.gradle.kts

@@ -137,15 +137,7 @@ if (project.findProperty("react.internal.useHermesStable")?.toString()?.toBoolea
     )
   }
 
-  val hermesV1Enabled = project.findProperty("hermesV1Enabled")?.toString()?.toBoolean() ?: true
-  // Hermes V1 stable releases are published without the -SNAPSHOT suffix.
-  // Legacy nightly builds use -SNAPSHOT.
-  val resolvedVersion =
-      if (hermesV1Enabled) hermesCompilerVersion else "$hermesCompilerVersion-SNAPSHOT"
-  val reason =
-      if (hermesV1Enabled) "Users opted to use hermes V1 stable"
-      else "Users opted to use hermes nightly"
-  hermesSubstitution = resolvedVersion to reason
+  hermesSubstitution = hermesCompilerVersion to "Users opted to use prebuilt hermes release"
 } else {
   logger.warn(
       """

gradle.properties

@@ -24,6 +24,3 @@ react.internal.useHermesStable=false
 # Controls whether to use Hermes from nightly builds. This will speed up builds
 # but should NOT be turned on for CI or release builds.
 react.internal.useHermesNightly=true
-
-# Controls whether to use Hermes 1.0. Clean and rebuild when changing.
-hermesV1Enabled=true

packages/gradle-plugin/react-native-gradle-plugin/src/main/kotlin/com/facebook/react/ReactPlugin.kt

@@ -28,8 +28,8 @@ import com.facebook.react.utils.DependencyUtils.readVersionAndGroupStrings
 import com.facebook.react.utils.JdkConfiguratorUtils.configureJavaToolChains
 import com.facebook.react.utils.JsonUtils
 import com.facebook.react.utils.NdkConfiguratorUtils.configureReactNativeNdk
-import com.facebook.react.utils.ProjectUtils.isHermesV1Enabled
 import com.facebook.react.utils.ProjectUtils.needsCodegenFromPackageJson
+import com.facebook.react.utils.PropertyUtils
 import com.facebook.react.utils.findPackageJsonFile
 import java.io.File
 import kotlin.system.exitProcess
@@ -55,8 +55,25 @@ class ReactPlugin : Plugin<Project> {
                 project,
             )
 
-    if (!project.rootProject.isHermesV1Enabled) {
-      rootExtension.hermesV1Enabled.set(false)
+    // Warn users if they still have the hermesV1Enabled property set.
+    if (
+        project.rootProject.hasProperty(PropertyUtils.HERMES_V1_ENABLED) ||
+            project.rootProject.hasProperty(PropertyUtils.SCOPED_HERMES_V1_ENABLED)
+    ) {
+      val value =
+          (project.rootProject.findProperty(PropertyUtils.HERMES_V1_ENABLED)
+                  ?: project.rootProject.findProperty(PropertyUtils.SCOPED_HERMES_V1_ENABLED))
+              .toString()
+              .toBoolean()
+      if (value) {
+        project.logger.warn(
+            "WARNING: The 'hermesV1Enabled' property is no longer needed. Hermes V1 is now always enabled. You can safely remove this property from your gradle.properties."
+        )
+      } else {
+        project.logger.warn(
+            "WARNING: Opting out of Hermes V1 is no longer supported. The 'hermesV1Enabled=false' property will be ignored. Hermes V1 is now always enabled. Please remove this property from your gradle.properties."
+        )
+      }
     }
 
     // App Only Configuration
@@ -75,8 +92,7 @@ class ReactPlugin : Plugin<Project> {
             File(reactNativeDir, "sdks/hermes-engine/version.properties")
         val versionAndGroupStrings =
             readVersionAndGroupStrings(project, propertiesFile, hermesVersionPropertiesFile)
-        val hermesV1Enabled = rootExtension.hermesV1Enabled.get()
-        configureDependencies(project, versionAndGroupStrings, hermesV1Enabled)
+        configureDependencies(project, versionAndGroupStrings)
         configureRepositories(project, versionAndGroupStrings.isNightly)
       }
 

packages/gradle-plugin/react-native-gradle-plugin/src/main/kotlin/com/facebook/react/internal/PrivateReactExtension.kt

@@ -59,5 +59,4 @@ abstract class PrivateReactExtension @Inject constructor(project: Project) {
   val codegenDir: DirectoryProperty =
       objects.directoryProperty().convention(root.dir("node_modules/@react-native/codegen"))
 
-  val hermesV1Enabled: Property<Boolean> = objects.property(Boolean::class.java).convention(true)
 }

packages/gradle-plugin/react-native-gradle-plugin/src/main/kotlin/com/facebook/react/utils/DependencyUtils.kt

@@ -119,23 +119,16 @@ internal object DependencyUtils {
   fun configureDependencies(
       project: Project,
       coordinates: Coordinates,
-      hermesV1Enabled: Boolean = true,
   ) {
-    if (
-        coordinates.versionString.isBlank() ||
-            (!hermesV1Enabled && coordinates.hermesVersionString.isBlank()) ||
-            (hermesV1Enabled && coordinates.hermesV1VersionString.isBlank())
-    )
-        return
+    if (coordinates.versionString.isBlank() || coordinates.hermesV1VersionString.isBlank()) return
     project.rootProject.allprojects { eachProject ->
       eachProject.configurations.all { configuration ->
         // Here we set a dependencySubstitution for both react-native and hermes-engine as those
         // coordinates are voided due to https://github.com/facebook/react-native/issues/35210
         // This allows users to import libraries that are still using
         // implementation("com.facebook.react:react-native:+") and resolve the right dependency.
         configuration.resolutionStrategy.dependencySubstitution {
-          getDependencySubstitutions(coordinates, hermesV1Enabled).forEach { (module, dest, reason)
-            ->
+          getDependencySubstitutions(coordinates).forEach { (module, dest, reason) ->
             it.substitute(it.module(module)).using(it.module(dest)).because(reason)
           }
         }
@@ -146,7 +139,7 @@ internal object DependencyUtils {
           // Contributors only: The hermes-engine version is forced only if the user has
           // not opted into using nightlies for local development.
           configuration.resolutionStrategy.force(
-              "${coordinates.hermesGroupString}:hermes-android:${if (hermesV1Enabled) coordinates.hermesV1VersionString else coordinates.hermesVersionString}"
+              "${coordinates.hermesGroupString}:hermes-android:${coordinates.hermesV1VersionString}"
           )
         }
       }
@@ -155,12 +148,10 @@ internal object DependencyUtils {
 
   internal fun getDependencySubstitutions(
       coordinates: Coordinates,
-      hermesV1Enabled: Boolean = true,
   ): List<Triple<String, String, String>> {
     val dependencySubstitution = mutableListOf<Triple<String, String, String>>()
-    val hermesVersion =
-        if (hermesV1Enabled) coordinates.hermesV1VersionString else coordinates.hermesVersionString
-    val hermesVersionString = "${coordinates.hermesGroupString}:hermes-android:${hermesVersion}"
+    val hermesVersionString =
+        "${coordinates.hermesGroupString}:hermes-android:${coordinates.hermesV1VersionString}"
     dependencySubstitution.add(
         Triple(
             "com.facebook.react:react-native",

packages/gradle-plugin/react-native-gradle-plugin/src/main/kotlin/com/facebook/react/utils/ProjectUtils.kt

@@ -13,11 +13,9 @@ import com.facebook.react.utils.KotlinStdlibCompatUtils.lowercaseCompat
 import com.facebook.react.utils.KotlinStdlibCompatUtils.toBooleanStrictOrNullCompat
 import com.facebook.react.utils.PropertyUtils.EDGE_TO_EDGE_ENABLED
 import com.facebook.react.utils.PropertyUtils.HERMES_ENABLED
-import com.facebook.react.utils.PropertyUtils.HERMES_V1_ENABLED
 import com.facebook.react.utils.PropertyUtils.REACT_NATIVE_ARCHITECTURES
 import com.facebook.react.utils.PropertyUtils.SCOPED_EDGE_TO_EDGE_ENABLED
 import com.facebook.react.utils.PropertyUtils.SCOPED_HERMES_ENABLED
-import com.facebook.react.utils.PropertyUtils.SCOPED_HERMES_V1_ENABLED
 import com.facebook.react.utils.PropertyUtils.SCOPED_REACT_NATIVE_ARCHITECTURES
 import com.facebook.react.utils.PropertyUtils.SCOPED_USE_THIRD_PARTY_JSC
 import com.facebook.react.utils.PropertyUtils.USE_THIRD_PARTY_JSC
@@ -29,7 +27,6 @@ internal object ProjectUtils {
 
   const val HERMES_FALLBACK = true
 
-  const val HERMES_V1_ENABLED_FALLBACK = true
 
   internal fun Project.isNewArchEnabled(): Boolean = true
 
@@ -73,23 +70,6 @@ internal object ProjectUtils {
             (project.hasProperty(SCOPED_USE_THIRD_PARTY_JSC) &&
                 project.property(SCOPED_USE_THIRD_PARTY_JSC).toString().toBoolean())
 
-  internal val Project.isHermesV1Enabled: Boolean
-    get() =
-        if (
-            project.hasProperty(HERMES_V1_ENABLED) || project.hasProperty(SCOPED_HERMES_V1_ENABLED)
-        ) {
-          (project.hasProperty(HERMES_V1_ENABLED) &&
-              project.property(HERMES_V1_ENABLED).toString().toBoolean()) ||
-              (project.hasProperty(SCOPED_HERMES_V1_ENABLED) &&
-                  project.property(SCOPED_HERMES_V1_ENABLED).toString().toBoolean()) ||
-              (project.extraProperties.has(HERMES_V1_ENABLED) &&
-                  project.extraProperties.get(HERMES_V1_ENABLED).toString().toBoolean()) ||
-              (project.extraProperties.has(SCOPED_HERMES_V1_ENABLED) &&
-                  project.extraProperties.get(SCOPED_HERMES_V1_ENABLED).toString().toBoolean())
-        } else {
-          HERMES_V1_ENABLED_FALLBACK
-        }
-
   internal fun Project.needsCodegenFromPackageJson(rootProperty: DirectoryProperty): Boolean {
     val parsedPackageJson = readPackageJsonFile(this, rootProperty)
     return needsCodegenFromPackageJson(parsedPackageJson)