public function resolve($parent, $child)
    {
        if ($child === "") {
            return $parent;
        }

        if ($child{0} === '/') {
            if ($parent === '/') {
                return $child;
            }

            return $parent . $child;
        }

        if ($parent === '/') {
            return $parent . $child;
        }

        return $parent . '/' . $child;
    }