'Calling L{_InputStream.readline} with a negative integer as an argument
returns one line from the input stream.'

def test_readlineNegative(self):

    bytes = 'input    stream    line    one\nline    two'
    d = self._renderAndReturnReaderResult((lambda input: input.readline((-1))), bytes)
    d.addCallback(self.assertEqual, 'input    stream    line    one\n')
    return d
