cut.py

import re
import pytest


def cut_by_re(s):
    return re.sub(r'\([^)]*$', '', s)


def cut_by_state(s):
    final = ''
    temp = ''
    in_parentheses = False

    for c in s:
        if c == '(':
            in_parentheses = True
            temp += c

        elif c == ')':
            in_parentheses = False
            final += temp + c
            temp = ''

        else:
            if in_parentheses:
                temp += c
            else:
                final += c

    if not in_parentheses:
        final += temp

    return final


checks = '''
esdfd((esdf)(esdf esdfd((esdf)
a a
a(b a
a(( a
a(b) a(b)
a(b)c a(b)c
a(b(c) a(b(c)
a(b(c a
a(()()( a(()()
a(b(c()b(c a(b(c()b
a((bb))()(c a((bb))()
'''.strip()


@pytest.mark.parametrize('func_name', ['cut_by_re', 'cut_by_state'])
def test_state(func_name):
    func = globals()[func_name]
    for check in checks.split('\n'):
        start, finish = check.split(' ')
        assert func(start) == finish