anchor.diff:  
     final String outputPath = path.join(projectDir.path, outputDirectoryName);
   
  -  // Xcode changed the name of this generated directory in Xcode 12.
  -  const String xcode11ArmDirectoryName = 'ios-armv7_arm64';
  -  const String xcode12ArmDirectoryName = 'ios-arm64_armv7';
  -
  -  final String xcode11AppFrameworkDirectory = path.join(
  -    outputPath,
  -    'Debug',
  -    'App.xcframework',
  -    xcode11ArmDirectoryName,
  -    'App.framework',
  -    'App',
  -  );
  -  final String xcode12AppFrameworkDirectory = path.join(
  -    outputPath,
  -    'Debug',
  -    'App.xcframework',
  -    xcode12ArmDirectoryName,
  -    'App.framework',
  -    'App',
  -  );
  -
  -  // Based on the locally installed version of Xcode.
  -  String localXcodeArmDirectoryName;
  -  if (exists(File(xcode11AppFrameworkDirectory))) {
  -    localXcodeArmDirectoryName = xcode11ArmDirectoryName;
  -  } else if (exists(File(xcode12AppFrameworkDirectory))) {
  -    localXcodeArmDirectoryName = xcode12ArmDirectoryName;
  -  } else {
  -    throw const FileSystemException('Expected App.framework binary to exist.');
  -  }
  -
  -  final String xcode11FlutterFrameworkDirectory = path.join(
  +  checkFileExists(path.join(
       outputPath,
       'Debug',
       'Flutter.xcframework',
  -    xcode11ArmDirectoryName,
  +    'ios-arm64_armv7',
       'Flutter.framework',
       'Flutter',
  -  );
  -  final String xcode12FlutterFrameworkDirectory = path.join(
  -    outputPath,
  -    'Debug',
  -    'Flutter.xcframework',
  -    xcode12ArmDirectoryName,
  -    'Flutter.framework',
  -    'Flutter',
  -  );
  -
  -  // Based on the version of Xcode installed on the engine builder.
  -  String builderXcodeArmDirectoryName;
  -  if (exists(File(xcode11FlutterFrameworkDirectory))) {
  -    builderXcodeArmDirectoryName = xcode11ArmDirectoryName;
  -  } else if (exists(File(xcode12FlutterFrameworkDirectory))) {
  -    builderXcodeArmDirectoryName = xcode12ArmDirectoryName;
  -  } else {
  -    throw const FileSystemException('Expected Flutter.framework binary to exist.');
  -  }
  +  ));
   
     final String debugAppFrameworkPath = path.join(
       outputPath,
       'Debug',
       'App.xcframework',
  -    localXcodeArmDirectoryName,
  +    'ios-arm64_armv7',
       'App.framework',
       'App',
     );
  
positive.code:       outputPath,
        mode,
        'Flutter.xcframework',
        builderXcodeArmDirectoryName,
        'Flutter.framework',
        'Flutter',
      );
  
negative.code:       outputPath,
        mode,
        'App.xcframework',
        'ios-arm64_armv7',
        'App.framework',
        'flutter_assets',
        'vm_snapshot_data',
  