def read_rule_tokens_until()

in cqlsh-expansion/pylib/cqlshlib/pylexotron.py [0:0]

• 53 lines of code
• 23 McCabe index (conditional complexity)

    def read_rule_tokens_until(cls, endtoks, tokeniter):
        if isinstance(endtoks, basestring):
            endtoks = (endtoks,)
        counttarget = None
        if isinstance(endtoks, int):
            counttarget = endtoks
            endtoks = ()
        countsofar = 0
        myrules = []
        mybranches = [myrules]
        for t in tokeniter:
            countsofar += 1
            if t in endtoks:
                if len(mybranches) == 1:
                    return cls.mkrule(mybranches[0])
                return choice(map(cls.mkrule, mybranches))
            if isinstance(t, tuple):
                if t[0] == 'reference':
                    t = rule_reference(t[1])
                elif t[0] == 'litstring':
                    if t[1][1].isalnum() or t[1][1] == '_':
                        t = word_match(t[1])
                    else:
                        t = text_match(t[1])
                elif t[0] == 'regex':
                    t = regex_rule(t[1])
                elif t[0] == 'named_collector':
                    t = named_collector(t[1], cls.read_rule_tokens_until(1, tokeniter))
                elif t[0] == 'named_symbol':
                    t = named_symbol(t[1], cls.read_rule_tokens_until(1, tokeniter))
            elif t == '(':
                t = cls.read_rule_tokens_until(')', tokeniter)
            elif t == '?':
                t = one_or_none(myrules.pop(-1))
            elif t == '*':
                t = repeat(myrules.pop(-1))
            elif t == '@':
                x = tokeniter.next()
                if not isinstance(x, tuple) or x[0] != 'litstring':
                    raise ValueError("Unexpected token %r following '@'" % (x,))
                t = case_match(x[1])
            elif t == '|':
                myrules = []
                mybranches.append(myrules)
                continue
            else:
                raise ValueError('Unparseable rule token %r after %r' % (t, myrules[-1]))
            myrules.append(t)
            if countsofar == counttarget:
                if len(mybranches) == 1:
                    return cls.mkrule(mybranches[0])
                return choice(map(cls.mkrule, mybranches))
        raise ValueError('Unexpected end of rule tokens')