Use hermesc from node_modules when consuming prebuilt hermes (#53581)

Summary:
Pull Request resolved: #53581

Changelog: [General][Changed] - Changed the source of hermesc binary to be an npm package

Reviewed By: cipolleschi, cortinico

Differential Revision: D81224001

fbshipit-source-id: 552d0e66fb891974d7b688bfc0bec95e19345d86

Author: j-piasecki

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

@@ -94,7 +94,12 @@ abstract class BundleHermesCTask : DefaultTask() {
     runCommand(bundleCommand)
 
     if (hermesEnabled.get()) {
-      val detectedHermesCommand = detectOSAwareHermesCommand(root.get().asFile, hermesCommand.get())
+      val hermesV1Enabled =
+          if (project.rootProject.hasProperty("hermesV1Enabled"))
+              project.rootProject.findProperty("hermesV1Enabled") == "true"
+          else false
+      val detectedHermesCommand =
+          detectOSAwareHermesCommand(root.get().asFile, hermesCommand.get(), hermesV1Enabled)
       val bytecodeFile = File("${bundleFile}.hbc")
       val outputSourceMap = resolveOutputSourceMap(bundleAssetFilename)
       val compilerSourceMap = resolveCompilerSourceMap(bundleAssetFilename)

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

@@ -122,11 +122,16 @@ private fun detectCliFile(reactNativeRoot: File, preconfiguredCliFile: File?): F
  *    used if the user is building Hermes from source.
  * 3. The file located in `node_modules/react-native/sdks/hermesc/%OS-BIN%/hermesc` where `%OS-BIN%`
  *    is substituted with the correct OS arch. This will be used if the user is using a precompiled
- *    hermes-engine package.
+ *    hermes-engine package. Or, if the user has opted in to use Hermes V1, the used file will be
+ *    located in `node_modules/hermes-compiler/%OS-BIN%/hermesc` where `%OS-BIN%` is substituted
+ *    with the correct OS arch.
  * 4. Fails otherwise
  */
-internal fun detectOSAwareHermesCommand(projectRoot: File, hermesCommand: String): String {
-  // 1. If the project specifies a Hermes command, don't second guess it.
+internal fun detectOSAwareHermesCommand(
+    projectRoot: File,
+    hermesCommand: String,
+    hermesV1Enabled: Boolean = false,
+): String { // 1. If the project specifies a Hermes command, don't second guess it.
   if (hermesCommand.isNotBlank()) {
     val osSpecificHermesCommand =
         if ("%OS-BIN%" in hermesCommand) {
@@ -146,9 +151,12 @@ internal fun detectOSAwareHermesCommand(projectRoot: File, hermesCommand: String
     return builtHermesc.cliPath(projectRoot)
   }
 
-  // 3. If the react-native contains a pre-built hermesc, use it.
+  // 3. If Hermes V1 is enabled, use hermes-compiler from npm, otherwise, if the
+  // react-native contains a pre-built hermesc, use it.
+  val hermesCPath = if (hermesV1Enabled) HERMES_COMPILER_NPM_DIR else HERMESC_IN_REACT_NATIVE_DIR
   val prebuiltHermesPath =
-      HERMESC_IN_REACT_NATIVE_DIR.plus(getHermesCBin())
+      hermesCPath
+          .plus(getHermesCBin())
           .replace("%OS-BIN%", getHermesOSBin())
           // Execution on Windows fails with / as separator
           .replace('/', File.separatorChar)
@@ -233,6 +241,7 @@ internal fun readPackageJsonFile(
   return packageJson?.let { JsonUtils.fromPackageJson(it) }
 }
 
+private const val HERMES_COMPILER_NPM_DIR = "node_modules/hermes-compiler/%OS-BIN%/"
 private const val HERMESC_IN_REACT_NATIVE_DIR = "node_modules/react-native/sdks/hermesc/%OS-BIN%/"
 private const val HERMESC_BUILT_FROM_SOURCE_DIR =
     "node_modules/react-native/ReactAndroid/hermes-engine/build/hermes/bin/"

packages/gradle-plugin/react-native-gradle-plugin/src/test/kotlin/com/facebook/react/utils/PathUtilsTest.kt

@@ -162,6 +162,16 @@ class PathUtilsTest {
     assertThat(detectOSAwareHermesCommand(tempFolder.root, "")).isEqualTo(expected.toString())
   }
 
+  @Test
+  @WithOs(OS.MAC)
+  fun detectOSAwareHermesCommand_withHermesV1Enabled() {
+    tempFolder.newFolder("node_modules/hermes-compiler/osx-bin/")
+    val expected = tempFolder.newFile("node_modules/hermes-compiler/osx-bin//hermesc")
+
+    assertThat(detectOSAwareHermesCommand(tempFolder.root, "", hermesV1Enabled = true))
+        .isEqualTo(expected.toString())
+  }
+
   @Test(expected = IllegalStateException::class)
   @WithOs(OS.MAC)
   fun detectOSAwareHermesCommand_failsIfNotFound() {

packages/react-native/sdks/hermes-engine/hermes-engine.podspec

@@ -63,6 +63,21 @@ Pod::Spec.new do |spec|
       ss.osx.vendored_frameworks = "destroot/Library/Frameworks/macosx/hermesvm.framework"
     end
 
+    # When using the local prebuilt tarball, it should include hermesc compatible with the used VM.
+    # In other cases, when using Hermes V1, the prebuilt versioned binaries can be used.
+    # TODO: T236142916 hermesc should be consumed from NPM even when not using Hermes V1
+    if source_type != HermesEngineSourceType::LOCAL_PREBUILT_TARBALL && ENV['RCT_HERMES_V1_ENABLED'] == "1"
+      hermes_compiler_path = File.dirname(Pod::Executable.execute_command('node', ['-p',
+        'require.resolve(
+        "hermes-compiler",
+        {paths: [process.argv[1]]}
+        )', __dir__]).strip
+      )
+
+      spec.user_target_xcconfig = {
+        'HERMES_CLI_PATH' => "#{hermes_compiler_path}/osx-bin/hermesc"
+      }
+    end
 
     # Right now, even reinstalling pods with the PRODUCTION flag turned on, does not change the version of hermes that is downloaded
     # To remove the PRODUCTION flag, we want to download the right version of hermes on the flight