public function update($username, $repository, $pullRequest, $id, $body)
    {
        if (!is_string($body)) {
            throw new InvalidArgumentException(sprintf('"body" must be a valid string ("%s" given).', gettype($body)));
        }

        if (empty($body)) {
            throw new InvalidArgumentException('"body" is mandatory and cannot be empty');
        }

        return $this->put('/repos/'.rawurlencode($username).'/'.rawurlencode($repository).'/pulls/'.$pullRequest.'/reviews/'.$id, [
            'body' => $body,
        ]);
    }