'L{ServerSupportedFeatures._parsePrefixParam} parses the ISUPPORT PREFIX
parameter into a mapping from modes to prefix symbols, returns
L{None} if there is no parseable prefix parameter or raises
C{ValueError} if the prefix parameter is malformed.'

def test_parsePrefixParam(self):

    _parsePrefixParam = irc.ServerSupportedFeatures._parsePrefixParam
    self.assertEqual(_parsePrefixParam(''), None)
    self.assertRaises(ValueError, _parsePrefixParam, 'hello')
    self.assertEqual(_parsePrefixParam('(ov)@+'), {'o': ('@', 0), 'v': ('+', 1)})
