code: public function fileExists($fileName): bool
      {
          if (! $this->exists()) {
              return false;
          }
          
          $file = sprintf("%s/%s", $this->path, $fileName);
          
          return file_exists($file);
      }
docs: Check whether a particular file exist in directory
  
  @param string $fileName
  The file name to check
  
  @throws DirectoryException
  
  @return bool