protected function scan_file($file_name)
 {
     try {
         $this->logger->info('Scanning ' . $file_name);
         $code = file_get_contents($file_name);
         $this->traverser->traverse($this->parser->parse($code));
     } catch (Error $e) {
         $this->logger->error('Parse Error: ' . $e->getMessage());
     }
     foreach ($this->collector->get() as $result) {
         $this->logger->notice($result['function'] . '(): ' . $result['item']);
     }
     $this->collector->reset();
 }