def test_readNegative(self):
        """
        Calling L{_InputStream.read} with a negative integer as an argument
        returns all bytes in the input stream.
        """
        bytes = b"all of the input"
        d = self._renderAndReturnReaderResult(
            lambda input: input.read(-1), bytes)
        d.addCallback(self.assertEqual, bytes)
        return d

        Calling L{_InputStream.read} with a negative integer as an argument
        returns all bytes in the input stream.
        
stackoverflow/venv/lib/python3.6/site-packages/twisted/web/test/test_wsgi.py