public function assertResponseStatusLineIsNot($line) {
        $this->requireResponse();

        try {
            $actualStatusLine = sprintf(
                '%d %s',
                $this->response->getStatusCode(),
                $this->response->getReasonPhrase()
            );

            Assertion::notSame($line, $actualStatusLine, sprintf(
                'Did not expect response status line "%s".',
                $line
            ));
        } catch (AssertionFailure $e) {
            throw new AssertionFailedException($e->getMessage());
        }
    }