anchor.diff:    stderr.write(message);
     exit(2);
   }
  +
  +final bool assertsEnabled = () {
  +  try {
  +    assert(false);
  +    return false;
  +  } catch (_) {
  +    return true;
  +  }
  +}();
  
positive.code:     arguments.addAll(remainingArguments);
      arguments.addAll(scriptArguments);
  
      print('Running: ${script} ${arguments.join(' ')}');
      await mainFunction(arguments);
    }
  }
  
negative.code:       stop("'$command' isn't a valid subcommand.");
    }
  
    if (extraVmArguments.isNotEmpty || !assertsEnabled) {
      List<String> arguments = [];
      arguments.addAll(extraVmArguments);
      arguments.add('--enable-asserts');
  