protected function parseLinterOutput($output)
 {
     $json = json_decode($output, true);
     $files = $json['files'];
     $severityMap = array();
     $severityMap['refactor'] = 'warning';
     $severityMap['convention'] = 'warning';
     $severityMap['warning'] = 'warning';
     $severityMap['error'] = 'error';
     $severityMap['fatal'] = 'error';
     $messages = array();
     foreach ($files as $file) {
         foreach ($file['offenses'] as $offense) {
             $message = new ArcanistLintMessage();
             $message->setPath($file['path']);
             $message->setLine($offense['location']['line']);
             $message->setChar($offense['location']['column']);
             $message->setCode('RUBY');
             $message->setName($offense['cop_name']);
             $message->setDescription($offense['message']);
             $message->setseverity('error');
             $messages[] = $message;
         }
     }
     return $messages;
 }