DiDom\Query::buildXpath PHP Method

    public static function buildXpath($segments, $prefix = '//')
    {
        $tagName = isset($segments['tag']) ? $segments['tag'] : '*';
        $attributes = [];
        // if the id attribute specified
        if (isset($segments['id'])) {
            $attributes[] = sprintf('@id="%s"', $segments['id']);
        }
        // if the class attribute specified
        if (isset($segments['classes'])) {
            foreach ($segments['classes'] as $class) {
                $attributes[] = sprintf('contains(concat(" ", normalize-space(@class), " "), " %s ")', $class);
            }
        }
        // if the attributes specified
        if (isset($segments['attributes'])) {
            foreach ($segments['attributes'] as $name => $value) {
                $attributes[] = self::convertAttribute($name, $value);
            }
        }
        // if the pseudo class specified
        if (isset($segments['pseudo'])) {
            $expression = isset($segments['expr']) ? trim($segments['expr']) : '';
            $parameters = explode(',', $expression);
            $attributes[] = self::convertPseudo($segments['pseudo'], $parameters, $tagName);
        }
        if (count($attributes) === 0 and !isset($segments['tag'])) {
            throw new InvalidArgumentException('The array of segments should contain the name of the tag or at least one attribute');
        }
        $xpath = $prefix . $tagName;
        if ($count = count($attributes)) {
            $xpath .= $count > 1 ? sprintf('[(%s)]', implode(') and (', $attributes)) : sprintf('[%s]', $attributes[0]);
        }
        return $xpath;
    }

 /**
  * @param string CSS selector
  * @param array
  *
  * @return NodeList
  */
 public function findByRule($selector, $rules, $wrapElement = true)
 {
     $segments = $selector !== null ? Query::getSegments($selector) : [];
     $xpath = Query::buildXpath(array_merge($segments, $rules));
     return $this->xpath($xpath, $wrapElement);
 }