Gaufrette\Adapter\Ftp::isDir PHP Method

    private function isDir($directory)
    {
        if ('/' === $directory) {
            return true;
        }
        if (!@ftp_chdir($this->getConnection(), $directory)) {
            return false;
        }
        // change directory again to return in the base directory
        ftp_chdir($this->getConnection(), $this->directory);
        return true;
    }