Remove the option to use JSC from core

cipolleschi · facebook-github-bot · commit 22875fe9e483 · 2025-06-11T03:23:39.000-07:00
Summary:
This change simplified the setp disallowing to use JSC from core.
As a side effect, it simplified the setup by always falling back to hermes if the users decides not to use the third party JSC

## Changelog:
[iOS][Removed] - remove the option to use JSC from core

Differential Revision: D76342625
diff --git a/packages/react-native/Libraries/AppDelegate/React-RCTAppDelegate.podspec b/packages/react-native/Libraries/AppDelegate/React-RCTAppDelegate.podspec
@@ -17,12 +17,8 @@ else
 end
 
 is_new_arch_enabled = ENV["RCT_NEW_ARCH_ENABLED"] != "0"
-use_hermes = ENV['USE_HERMES'] == nil || ENV['USE_HERMES'] == '1'
-
 new_arch_enabled_flag = (is_new_arch_enabled ? " -DRCT_NEW_ARCH_ENABLED=1" : "")
-hermes_flag = (use_hermes ? " -DUSE_HERMES=1" : "")
-use_third_party_jsc_flag = ENV['USE_THIRD_PARTY_JSC'] == '1' ? " -DUSE_THIRD_PARTY_JSC=1" : ""
-other_cflags = "$(inherited) " + new_arch_enabled_flag + hermes_flag + use_third_party_jsc_flag
+other_cflags = "$(inherited) " + new_arch_enabled_flag + js_engine_flags()
 
 header_search_paths = [
   "$(PODS_TARGET_SRCROOT)/../../ReactCommon",
@@ -31,7 +27,7 @@ header_search_paths = [
   "$(PODS_ROOT)/Headers/Public/ReactCommon",
   "$(PODS_ROOT)/Headers/Public/React-RCTFabric",
   "$(PODS_ROOT)/Headers/Private/Yoga",
-].concat(use_hermes ? [
+].concat(use_hermes() ? [
   "$(PODS_ROOT)/Headers/Public/React-hermes",
   "$(PODS_ROOT)/Headers/Public/hermes-engine"
 ] : [])
@@ -66,7 +62,7 @@ Pod::Spec.new do |s|
   s.dependency "React-CoreModules"
   s.dependency "React-RCTFBReactNativeSpec"
   s.dependency "React-defaultsnativemodule"
-  if use_hermes
+  if use_hermes()
     s.dependency 'React-hermes'
   end
 
diff --git a/packages/react-native/Libraries/Blob/React-RCTBlob.podspec b/packages/react-native/Libraries/Blob/React-RCTBlob.podspec
@@ -50,7 +50,7 @@ Pod::Spec.new do |s|
   add_dependency(s, "React-jsinspectorcdp", :framework_name => 'jsinspector_moderncdp')
   add_dependency(s, "ReactCommon", :subspec => "turbomodule/core", :additional_framework_paths => ["react/nativemodule/core"])
 
-  if ENV["USE_HERMES"] == nil || ENV["USE_HERMES"] == "1"
+  if use_hermes()
     s.dependency "hermes-engine"
   end
 
diff --git a/packages/react-native/React-Core.podspec b/packages/react-native/React-Core.podspec
@@ -16,10 +16,6 @@ else
   source[:tag] = "v#{version}"
 end
 
-use_hermes = ENV['USE_HERMES'] == nil || ENV['USE_HERMES'] == '1'
-use_hermes_flag = use_hermes ? "-DUSE_HERMES=1" : ""
-use_third_party_jsc_flag = ENV['USE_THIRD_PARTY_JSC'] == '1' ? "-DUSE_THIRD_PARTY_JSC=1" : ""
-
 header_subspecs = {
   'CoreModulesHeaders'          => 'React/CoreModules/**/*.h',
   'RCTActionSheetHeaders'       => 'Libraries/ActionSheetIOS/*.h',
@@ -35,7 +31,7 @@ header_subspecs = {
 }
 
 frameworks_search_paths = []
-frameworks_search_paths << "\"$(PODS_CONFIGURATION_BUILD_DIR)/React-hermes\"" if use_hermes
+frameworks_search_paths << "\"$(PODS_CONFIGURATION_BUILD_DIR)/React-hermes\"" if use_hermes()
 
 header_search_paths = [
   "$(PODS_TARGET_SRCROOT)/ReactCommon",
@@ -56,7 +52,7 @@ Pod::Spec.new do |s|
   s.platforms              = min_supported_versions
   s.source                 = source
   s.resource_bundle        = { "RCTI18nStrings" => ["React/I18n/strings/*.lproj"]}
-  s.compiler_flags         = use_hermes_flag + ' ' + use_third_party_jsc_flag
+  s.compiler_flags         = js_engine_flags()
   s.header_dir             = "React"
   s.weak_framework         = "JavaScriptCore"
   s.pod_target_xcconfig    = {
@@ -80,13 +76,9 @@ Pod::Spec.new do |s|
       "React/Inspector/**/*",
       "React/Runtime/**/*",
     ]
-    # If we are using Hermes (the default is use hermes, so USE_HERMES can be nil), we don't have jsc installed
-    # So we have to exclude the JSCExecutorFactory
-    if use_hermes
-      exclude_files = exclude_files.append("React/CxxBridge/JSCExecutorFactory.{h,mm}")
-    elsif ENV['USE_THIRD_PARTY_JSC'] == '1'
-      exclude_files = exclude_files.append("React/CxxBridge/JSCExecutorFactory.{h,mm}")
-    end
+    
+    # The default is use hermes,  we don't have jsc installed
+    exclude_files = exclude_files.append("React/CxxBridge/JSCExecutorFactory.{h,mm}")
 
     ss.exclude_files = exclude_files
     ss.private_header_files   = "React/Cxx*/*.h"
@@ -123,7 +115,7 @@ Pod::Spec.new do |s|
   s.dependency "React-runtimescheduler"
   s.dependency "Yoga"
 
-  if use_hermes
+  if use_hermes()
     s.dependency "React-hermes"
   end
 
@@ -136,7 +128,6 @@ Pod::Spec.new do |s|
   add_dependency(s, "React-utils", :additional_framework_paths => ["react/utils/platform/ios"])
   add_dependency(s, "RCTDeprecation")
 
-
   depend_on_js_engine(s)
   add_rn_third_party_dependencies(s)
 end
diff --git a/packages/react-native/React/Runtime/React-RCTRuntime.podspec b/packages/react-native/React/Runtime/React-RCTRuntime.podspec
@@ -58,15 +58,14 @@ Pod::Spec.new do |s|
   add_dependency(s, "React-RuntimeCore")
   add_dependency(s, "React-RuntimeApple")
 
-  if ENV["USE_HERMES"] == nil || ENV["USE_HERMES"] == "1"
+  if use_third_party_jsc()
+    s.exclude_files = ["RCTHermesInstanceFactory.{mm,h}", "RCTJscInstanceFactory.{mm,h}"]
+  else
     s.dependency "hermes-engine"
     add_dependency(s, "React-RuntimeHermes")
     s.exclude_files = "RCTJscInstanceFactory.{h,mm}"
-  elsif ENV['USE_THIRD_PARTY_JSC'] == '1'
-    s.exclude_files = ["RCTHermesInstanceFactory.{mm,h}", "RCTJscInstanceFactory.{mm,h}"]
-  else
-    s.exclude_files = ["RCTHermesInstanceFactory.{mm,h}"]
   end
+
   depend_on_js_engine(s)
   add_rn_third_party_dependencies(s)
 end
diff --git a/packages/react-native/ReactCommon/ReactCommon.podspec b/packages/react-native/ReactCommon/ReactCommon.podspec
@@ -16,8 +16,6 @@ else
   source[:tag] = "v#{version}"
 end
 
-using_hermes = ENV['USE_HERMES'] == nil || ENV['USE_HERMES'] == "1"
-
 Pod::Spec.new do |s|
   s.name                   = "ReactCommon"
   s.module_name            = "ReactCommon"
@@ -48,7 +46,7 @@ Pod::Spec.new do |s|
     ss.dependency "React-cxxreact", version
     ss.dependency "React-jsi", version
     ss.dependency "React-logger", version
-    if using_hermes
+    if use_hermes()
       ss.dependency "hermes-engine"
     end
 
@@ -58,7 +56,7 @@ Pod::Spec.new do |s|
       sss.exclude_files        = "react/bridging/tests"
       sss.header_dir           = "react/bridging"
       sss.pod_target_xcconfig  = { "HEADER_SEARCH_PATHS" => "\"$(PODS_TARGET_SRCROOT)/ReactCommon\"" }
-      if using_hermes
+      if use_hermes()
         sss.dependency "hermes-engine"
       end
     end
diff --git a/packages/react-native/ReactCommon/cxxreact/React-cxxreact.podspec b/packages/react-native/ReactCommon/cxxreact/React-cxxreact.podspec
@@ -48,7 +48,7 @@ Pod::Spec.new do |s|
 
   s.resource_bundles = {'React-cxxreact_privacy' => 'PrivacyInfo.xcprivacy'}
 
-  if ENV['USE_HERMES'] == nil || ENV['USE_HERMES'] == "1"
+  if use_hermes()
     s.dependency 'hermes-engine'
   end
 
diff --git a/packages/react-native/ReactCommon/jserrorhandler/React-jserrorhandler.podspec b/packages/react-native/ReactCommon/jserrorhandler/React-jserrorhandler.podspec
@@ -44,7 +44,7 @@ Pod::Spec.new do |s|
   add_dependency(s, "React-featureflags")
   add_dependency(s, "React-debug")
 
-  if ENV['USE_HERMES'] == nil || ENV['USE_HERMES'] == "1"
+  if use_hermes()
     s.dependency 'hermes-engine'
   end
 
diff --git a/packages/react-native/ReactCommon/jsi/React-jsi.podspec b/packages/react-native/ReactCommon/jsi/React-jsi.podspec
@@ -5,10 +5,6 @@
 
 require "json"
 
-js_engine = ENV['USE_HERMES'] == "0" ?
-  :jsc :
-  :hermes
-
 package = JSON.parse(File.read(File.join(__dir__, "..", "..", "package.json")))
 version = package['version']
 
@@ -42,7 +38,7 @@ Pod::Spec.new do |s|
                       "jsi/jsilib-windows.cpp",
                       "**/test/*"
                      ]
-  if js_engine == :hermes
+  if use_hermes()
     # JSI is a part of hermes-engine. Including them also in react-native will violate the One Definition Rulle.
     files_to_exclude += [ "jsi/jsi.cpp" ]
     s.dependency "hermes-engine"
diff --git a/packages/react-native/ReactCommon/jsiexecutor/React-jsiexecutor.podspec b/packages/react-native/ReactCommon/jsiexecutor/React-jsiexecutor.podspec
@@ -36,7 +36,7 @@ Pod::Spec.new do |s|
   add_dependency(s, "React-jsinspector", :framework_name => 'jsinspector_modern')
   add_dependency(s, "React-jsinspectorcdp", :framework_name => 'jsinspector_moderncdp')
   add_dependency(s, "React-jsinspectortracing", :framework_name => 'jsinspector_moderntracing')
-  if ENV['USE_HERMES'] == nil || ENV['USE_HERMES'] == "1"
+  if use_hermes()
     s.dependency 'hermes-engine'
   end
 
diff --git a/packages/react-native/ReactCommon/jsinspector-modern/React-jsinspector.podspec b/packages/react-native/ReactCommon/jsinspector-modern/React-jsinspector.podspec
@@ -55,7 +55,7 @@ Pod::Spec.new do |s|
   add_dependency(s, "React-jsinspectornetwork", :framework_name => 'jsinspector_modernnetwork')
   add_dependency(s, "React-jsinspectortracing", :framework_name => 'jsinspector_moderntracing')
   s.dependency "React-perflogger", version
-  if ENV["USE_HERMES"] == nil || ENV["USE_HERMES"] == "1"
+  if use_hermes()
     s.dependency "hermes-engine"
   end
 
diff --git a/packages/react-native/ReactCommon/react/runtime/platform/ios/React-RuntimeApple.podspec b/packages/react-native/ReactCommon/react/runtime/platform/ios/React-RuntimeApple.podspec
@@ -62,15 +62,12 @@ Pod::Spec.new do |s|
   add_dependency(s, "React-RCTFBReactNativeSpec")
   add_dependency(s, "React-utils", :additional_framework_paths => ["react/utils/platform/ios"])
 
-  if ENV["USE_HERMES"] == nil || ENV["USE_HERMES"] == "1"
+  if use_third_party_jsc()
+    s.exclude_files = ["ReactCommon/RCTHermesInstance.{mm,h}", "ReactCommon/RCTJscInstance.{mm,h}"]
+  else
     s.dependency "hermes-engine"
     add_dependency(s, "React-RuntimeHermes")
     s.exclude_files = "ReactCommon/RCTJscInstance.{mm,h}"
-  elsif ENV['USE_THIRD_PARTY_JSC'] == '1'
-    s.exclude_files = ["ReactCommon/RCTHermesInstance.{mm,h}", "ReactCommon/RCTJscInstance.{mm,h}"]
-  else
-    s.dependency "React-jsc"
-    s.exclude_files = "ReactCommon/RCTHermesInstance.{mm,h}"
   end
 
   add_rn_third_party_dependencies(s)
diff --git a/packages/react-native/scripts/cocoapods/__tests__/jsengine-test.rb b/packages/react-native/scripts/cocoapods/__tests__/jsengine-test.rb
@@ -26,53 +26,9 @@ def teardown
         Pod::Config.reset()
         Pod::UI.reset()
         podSpy_cleanUp()
-        ENV['USE_HERMES'] = '1'
         ENV['CI'] = nil
     end
 
-    # =============== #
-    # TEST - setupJsc #
-    # =============== #
-    def test_setupJsc_installsPods
-        # Arrange
-        fabric_enabled = false
-
-        # Act
-        setup_jsc!(:react_native_path => @react_native_path, :fabric_enabled => fabric_enabled)
-
-        # Assert
-        assert_equal($podInvocationCount, 2)
-        assert_equal($podInvocation["React-jsi"][:path], "../../ReactCommon/jsi")
-        assert_equal($podInvocation["React-jsc"][:path], "../../ReactCommon/jsc")
-    end
-
-    def test_setupJsc_installsPods_installsFabricSubspecWhenFabricEnabled
-        # Arrange
-        fabric_enabled = true
-
-        # Act
-        setup_jsc!(:react_native_path => @react_native_path, :fabric_enabled => fabric_enabled)
-
-        # Assert
-        assert_equal($podInvocationCount, 3)
-        assert_equal($podInvocation["React-jsi"][:path], "../../ReactCommon/jsi")
-        assert_equal($podInvocation["React-jsc"][:path], "../../ReactCommon/jsc")
-        assert_equal($podInvocation["React-jsc/Fabric"][:path], "../../ReactCommon/jsc")
-    end
-
-    def test_setupJsc_installsPodsWithThirdPartyJSC
-        # Arrange
-        ENV['USE_THIRD_PARTY_JSC'] = '1'
-        fabric_enabled = false
-
-        # Act
-        setup_jsc!(:react_native_path => @react_native_path, :fabric_enabled => fabric_enabled)
-
-        # Assert
-        assert_equal($podInvocationCount, 1)
-        assert_equal($podInvocation["React-jsi"][:path], "../../ReactCommon/jsi")
-    end
-
     # ================== #
     # TEST - setupHermes #
     # ================== #
diff --git a/packages/react-native/scripts/cocoapods/__tests__/utils-test.rb b/packages/react-native/scripts/cocoapods/__tests__/utils-test.rb
@@ -34,7 +34,6 @@ def teardown
         Xcodeproj::Plist.reset()
         XcodebuildMock.reset()
         ENV['RCT_NEW_ARCH_ENABLED'] = '0'
-        ENV['USE_HERMES'] = '1'
         ENV['USE_FRAMEWORKS'] = nil
         system_reset_commands
         $RN_PLATFORMS = nil
@@ -106,21 +105,6 @@ def test_getDefaultFlag_whenOldArchitecture()
         })
     end
 
-    def test_getDefaultFlag_whenOldArchitectureButHermesDisabled()
-        # Arrange
-        ENV['RCT_NEW_ARCH_ENABLED'] = '0'
-        ENV['USE_HERMES'] = '0'
-
-        # Act
-        flags = ReactNativePodsUtils.get_default_flags()
-
-        # Assert
-        assert_equal(flags, {
-            :fabric_enabled => false,
-            :hermes_enabled => false,
-        })
-    end
-
     def test_getDefaultFlag_whenNewArchitecture()
         # Arrange
         ENV['RCT_NEW_ARCH_ENABLED'] = '1'
@@ -135,21 +119,6 @@ def test_getDefaultFlag_whenNewArchitecture()
         })
     end
 
-    def test_getDefaultFlag_whenNewArchitectureButHermesDisabled()
-        # Arrange
-        ENV['RCT_NEW_ARCH_ENABLED'] = '1'
-        ENV['USE_HERMES'] = '0'
-
-        # Act
-        flags = ReactNativePodsUtils.get_default_flags()
-
-        # Assert
-        assert_equal(flags, {
-            :fabric_enabled => true,
-            :hermes_enabled => false,
-        })
-    end
-
     # ============== #
     # TEST - has_pod #
     # ============== #
diff --git a/packages/react-native/scripts/cocoapods/jsengine.rb b/packages/react-native/scripts/cocoapods/jsengine.rb
@@ -5,19 +5,6 @@
 
 require_relative './utils.rb'
 
-# It sets up the JavaScriptCore.
-#
-# @parameter react_native_path: relative path to react-native
-# @parameter fabric_enabled: whether Fabirc is enabled
-def setup_jsc!(react_native_path: "../node_modules/react-native", fabric_enabled: false)
-    if ENV['USE_THIRD_PARTY_JSC'] != '1'
-        pod 'React-jsc', :path => "#{react_native_path}/ReactCommon/jsc"
-        if fabric_enabled
-            pod 'React-jsc/Fabric', :path => "#{react_native_path}/ReactCommon/jsc"
-        end
-    end
-end
-
 # It sets up the Hermes.
 #
 # @parameter react_native_path: relative path to react-native
@@ -32,11 +19,37 @@ def setup_hermes!(react_native_path: "../node_modules/react-native")
     pod 'React-hermes', :path => "#{react_native_path}/ReactCommon/hermes"
 end
 
+def use_third_party_jsc
+  return ENV['USE_THIRD_PARTY_JSC'] == '1'
+end
+
+# use Hermes is the default. The only other option is the third-party JSC
+# if the 3rd party JSC is not true, we always want to use Hermes.
+def use_hermes
+  return !use_third_party_jsc()
+end
+
+def use_hermes_flags
+  return "-DUSE_HERMES=1"
+end
+
+def use_third_party_jsc_flags
+  return "-DUSE_THIRD_PARTY_JSC=1"
+end
+
+def js_engine_flags()
+  if use_hermes()
+    return use_hermes_flags()
+  else
+    return use_third_party_jsc_flags()
+  end
+end
+
 # Utility function to depend on JS engine based on the environment variable.
 def depend_on_js_engine(s)
-  if ENV["USE_HERMES"] == nil || ENV["USE_HERMES"] == "1"
+  if use_hermes()
     s.dependency 'hermes-engine'
-  elsif ENV['USE_THIRD_PARTY_JSC'] != '1'
+  elsif use_third_party_jsc()
     s.dependency 'React-jsc'
   end
 end
diff --git a/packages/react-native/scripts/cocoapods/utils.rb b/packages/react-native/scripts/cocoapods/utils.rb
diff --git a/packages/react-native/scripts/react_native_pods.rb b/packages/react-native/scripts/react_native_pods.rb
diff --git a/packages/rn-tester/Podfile b/packages/rn-tester/Podfile
diff --git a/packages/rn-tester/README.md b/packages/rn-tester/README.md
diff --git a/scripts/release-testing/test-e2e-local.js b/scripts/release-testing/test-e2e-local.js
diff --git a/scripts/releases/__tests__/__fixtures__/remove-new-arch-flags-fixture.js b/scripts/releases/__tests__/__fixtures__/remove-new-arch-flags-fixture.js
