FluentDOM\Nodes\Modifier::insertNodesBefore PHP Method

    public function insertNodesBefore($contentNodes)
    {
        $result = array();
        if ($this->_node instanceof \DOMNode && !empty($contentNodes)) {
            foreach ($contentNodes as $contentNode) {
                /** @var \DOMNode $contentNode */
                $result[] = $this->getParentNode()->insertBefore($contentNode->cloneNode(TRUE), $this->_node);
            }
        }
        return $result;
    }