'If L{_IdentityTransferDecoder} is constructed with L{None} for the
content length, it passes all data delivered to it through to the data
callback.'

def test_unknownContentLength(self):

    data = []
    finish = []
    decoder = _IdentityTransferDecoder(None, data.append, finish.append)
    decoder.dataReceived('x')
    self.assertEqual(data, ['x'])
    decoder.dataReceived('y')
    self.assertEqual(data, ['x', 'y'])
    self.assertEqual(finish, [])
