PHPMD\RuleSetFactory::parseRuleSetNode PHP Method

    private function parseRuleSetNode($fileName)
    {
        // Hide error messages
        $libxml = libxml_use_internal_errors(true);
        $xml = simplexml_load_string(file_get_contents($fileName));
        if ($xml === false) {
            // Reset error handling to previous setting
            libxml_use_internal_errors($libxml);
            throw new \RuntimeException(trim(libxml_get_last_error()->message));
        }
        $ruleSet = new RuleSet();
        $ruleSet->setFileName($fileName);
        $ruleSet->setName((string) $xml['name']);
        if ($this->strict) {
            $ruleSet->setStrict();
        }
        foreach ($xml->children() as $node) {
            if ($node->getName() === 'php-includepath') {
                $includePath = (string) $node;
                if (is_dir(dirname($fileName) . DIRECTORY_SEPARATOR . $includePath)) {
                    $includePath = dirname($fileName) . DIRECTORY_SEPARATOR . $includePath;
                    $includePath = realpath($includePath);
                }
                $includePath = get_include_path() . PATH_SEPARATOR . $includePath;
                set_include_path($includePath);
            }
        }
        foreach ($xml->children() as $node) {
            if ($node->getName() === 'description') {
                $ruleSet->setDescription((string) $node);
            } elseif ($node->getName() === 'rule') {
                $this->parseRuleNode($ruleSet, $node);
            }
        }
        return $ruleSet;
    }