def test_extraBytesPassedBack(self):
        """
        If extra bytes are received past the end of a response, they are passed
        to the finish callback.
        """
        finished = []
        protocol = HTTPClientParser(
            Request(b'GET', b'/', _boringHeaders, None),
            finished.append)

        protocol.makeConnection(StringTransport())
        protocol.dataReceived(b'HTTP/1.1 200 OK\r\n')
        protocol.dataReceived(b'Content-Length: 0\r\n')
        protocol.dataReceived(b'\r\nHere is another thing!')
        self.assertEqual(protocol.state, DONE)
        self.assertEqual(finished, [b'Here is another thing!'])

        If extra bytes are received past the end of a response, they are passed
        to the finish callback.
        
stackoverflow/venv/lib/python3.6/site-packages/twisted/web/test/test_newclient.py