public function addOption(string $option, $value = null, string $glue = '=') : Executable
    {
        if ($value !== null) {
            // force space for multiple arguments e.g. --option 'foo' 'bar'
            if (is_array($value)) {
                $glue = ' ';
            }
            $value = $glue . $this->escapeArgument($value);
        } else {
            $value = '';
        }
        $this->options[] = $option . $value;

        return $this;
    }