x-component does not work with self-closing tag

[nodesiremonk]

It seems the self-closing tag (e.g. <x-component key="value" />) somehow will make the match[4] undefined in the callback function.

I tested the regex in preg_replace_callback() function and it seems the $match[4] should be empty rather than undefined in the case of using self-closing tag /> Not sure why it will throw an undefined error here.

As a temporary workaround, I have to add the ?? '' after $match[4] parameter to make it work for now.
$match[4] = $this->compileComponents( $match[4] ?? '');

Might need to investigate more for a better solution to fix the problem.

protected function compileComponents($value)
    {
        /**
         * @param array $match
         *                    [0]=full expression with @ and parenthesis
         *                    [1]=Component name
         *                    [2]=parameters
         *                    [3]=...
         *                    [4]=content
         *
         * @return string
         */

        $callback = function($match) {

            if(static::contains($match[0], 'x-')) {
                $match[4] = $this->compileComponents( $match[4]);
            }
            $paramsCompiled = $this->parseParams($match[2]);
            $str =  "('components.".$match[1]."',".$paramsCompiled.")";

            return self::compileComponent($str).$match[4].self::compileEndComponent();
        };
        return preg_replace_callback('/<x-([a-z0-9.-]+)(\s[^>]*)?(>((?:(?!<\/x-\1>).)*)<\/x-\1>|\/>)/ms', $callback, $value);

    }