Optimize flutter run logic for iOS by "ONLY_ACTIVE_ARCH=YES" if possible (#27817)

packages/flutter_tools/lib/src/ios/devices.dart

@@ -243,6 +243,9 @@ class IOSDevice extends Device {
       // TODO(chinmaygarde): Use mainPath, route.
       printTrace('Building ${package.name} for $id');
 
+      final String cpuArchitecture = await iMobileDevice.getInfoForDevice(id, 'CPUArchitecture');
+      final IOSArch iosArch = getIOSArchForName(cpuArchitecture);
+
       // Step 1: Build the precompiled/DBC application if necessary.
       final XcodeBuildResult buildResult = await buildXcodeProject(
           app: package,
@@ -250,6 +253,7 @@ class IOSDevice extends Device {
           targetOverride: mainPath,
           buildForDevice: true,
           usesTerminalUi: usesTerminalUi,
+          activeArch: iosArch
       );
       if (!buildResult.success) {
         printError('Could not build the precompiled application for the device.');

packages/flutter_tools/lib/src/ios/mac.dart

@@ -134,7 +134,7 @@ class IMobileDevice {
 
   Future<String> getInfoForDevice(String deviceID, String key) async {
     try {
-      final ProcessResult result = await processManager.run(<String>['ideviceinfo', '-u', deviceID, '-k', key, '--simple']);
+      final ProcessResult result = await processManager.run(<String>['ideviceinfo', '-u', deviceID, '-k', key]);
       if (result.exitCode == 255 && result.stdout != null && result.stdout.contains('No device found'))
         throw IOSDeviceNotFoundError('ideviceinfo could not find device:\n${result.stdout}');
       if (result.exitCode != 0)
@@ -294,6 +294,7 @@ Future<XcodeBuildResult> buildXcodeProject({
   BuildInfo buildInfo,
   String targetOverride,
   bool buildForDevice,
+  IOSArch activeArch,
   bool codesign = true,
   bool usesTerminalUi = true,
 }) async {
@@ -435,6 +436,14 @@ Future<XcodeBuildResult> buildXcodeProject({
     buildCommands.addAll(<String>['-sdk', 'iphonesimulator', '-arch', 'x86_64']);
   }
 
+  if (activeArch != null) {
+    final String activeArchName = getNameForIOSArch(activeArch);
+    if (activeArchName != null) {
+      buildCommands.add('ONLY_ACTIVE_ARCH=YES');
+      buildCommands.add('ARCHS=$activeArchName');
+    }
+  }
+
   if (!codesign) {
     buildCommands.addAll(
       <String>[

packages/flutter_tools/test/ios/mac_test.dart

@@ -130,7 +130,7 @@ void main() {
     });
 
     testUsingContext('getInfoForDevice throws IOSDeviceNotFoundError when ideviceinfo returns specific error code and message', () async {
-      when(mockProcessManager.run(<String>['ideviceinfo', '-u', 'foo', '-k', 'bar', '--simple']))
+      when(mockProcessManager.run(<String>['ideviceinfo', '-u', 'foo', '-k', 'bar']))
           .thenAnswer((_) => Future<ProcessResult>.value(ProcessResult(1, 255, 'No device found with udid foo, is it plugged in?', '')));
       expect(() async => await iMobileDevice.getInfoForDevice('foo', 'bar'), throwsA(isInstanceOf<IOSDeviceNotFoundError>()));
     }, overrides: <Type, Generator>{