public function checkSetting($setting) { $result = parent::checkSetting($setting); // Extra check to make sure the hosts file *does* exist if ($result) { $this->file_system = new FileSystem(); $hosts_file = drush_get_option('rum-hosts-file', ''); if ($this->file_system->checkFile($hosts_file)) { return TRUE; } else { throw new RumHostsFileDoesNotExist($hosts_file); } } return FALSE; }