public function sniffFileList($file_list) {
    $this->say("Sniffing directories containing changed files...");
    $files = explode("\n", $file_list);
    $files = array_filter($files);
    if ($files) {
      $temp_path = $this->getConfigValue('repo.root') . '/tmp/phpcs-fileset';
      $this->taskWriteToFile($temp_path)
        ->lines($files)
        ->run();
      $arguments = "--file-list='$temp_path' -l";
      $exit_code = $this->doSniff($arguments);
      unlink($temp_path);

      return $exit_code;
    }

    return 0;
  }