PageFinder::arrangeFields PHP Method

    protected function arrangeFields(array $fields)
    {
        $custom = array();
        $native = array();
        foreach ($fields as $name) {
            if ($this->wire('fields')->isNative($name)) {
                $native[] = $name;
            } else {
                $custom[] = $name;
            }
        }
        return array_merge($native, $custom);
    }