protected function getShortOptionError($option)
    {
        $out = [sprintf('Unknown short option `%s`', $option)];
        $out[] = '';
        $out[] = 'Available short options are :';
        $out[] = '';

        foreach ($this->_shortOptions as $short => $long) {
            $out[] = sprintf(' - `%s` (short for `--%s`)', $short, $long);
        }

        return implode("\n", $out);
    }