anchor.diff:  /// exit code.
   class DriveCommand extends RunCommandBase {
     DriveCommand() {
  +    usesPubOption();
       argParser.addFlag(
         'keep-app-running',
         negatable: true,
  
positive.code: Future<int> runTests(List<String> testArgs) async {
    printTrace('Running driver tests.');
  
    List<String> args = testArgs.toList()
      ..add('--packages=${PackageMap.globalPackagesPath}')
      ..add('-rexpanded');
  
negative.code: import '../application_package.dart';
  import '../base/file_system.dart';
  import '../base/common.dart';
  import '../base/os.dart';
  import '../build_info.dart';
  import '../cache.dart';
  import '../dart/package_map.dart';
  