[BUG] Latest version 1.1.10 does not seem to work with Python 3.12

[ojc-orchestra]

Describe the bug

Version 1.1.10 does not seem to work as expected on Python 3.12. Version 1.1.9 works as expected. I have not tested 1.1.10 on Python versions before 3.12.

To Reproduce

Python 3.12.1 (main, Dec  7 2023, 20:45:44) [Clang 15.0.0 (clang-1500.1.0.2.5)] on darwin
Type "help", "copyright", "credits" or "license" for more information.
>>> from aws_cron_expression_validator.validator import AWSCronExpressionValidator
>>> AWSCronExpressionValidator.validate("0 8 1 * ? *")
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/Users/olivercrawford/Documents/things/venv/lib/python3.12/site-packages/aws_cron_expression_validator/validator.py", line 83, in validate
    if not re.fullmatch(cls.month_regex(), month):
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/opt/homebrew/Cellar/python@3.12/3.12.1_1/Frameworks/Python.framework/Versions/3.12/lib/python3.12/re/__init__.py", line 172, in fullmatch
    return _compile(pattern, flags).fullmatch(string)
           ^^^^^^^^^^^^^^^^^^^^^^^^
  File "/opt/homebrew/Cellar/python@3.12/3.12.1_1/Frameworks/Python.framework/Versions/3.12/lib/python3.12/re/__init__.py", line 307, in _compile
    p = _compiler.compile(pattern, flags)
        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/opt/homebrew/Cellar/python@3.12/3.12.1_1/Frameworks/Python.framework/Versions/3.12/lib/python3.12/re/_compiler.py", line 745, in compile
    p = _parser.parse(p, flags)
        ^^^^^^^^^^^^^^^^^^^^^^^
  File "/opt/homebrew/Cellar/python@3.12/3.12.1_1/Frameworks/Python.framework/Versions/3.12/lib/python3.12/re/_parser.py", line 979, in parse
    p = _parse_sub(source, state, flags & SRE_FLAG_VERBOSE, 0)
        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/opt/homebrew/Cellar/python@3.12/3.12.1_1/Frameworks/Python.framework/Versions/3.12/lib/python3.12/re/_parser.py", line 460, in _parse_sub
    itemsappend(_parse(source, state, verbose, nested + 1,
                ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/opt/homebrew/Cellar/python@3.12/3.12.1_1/Frameworks/Python.framework/Versions/3.12/lib/python3.12/re/_parser.py", line 862, in _parse
    p = _parse_sub(source, state, sub_verbose, nested + 1)
        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/opt/homebrew/Cellar/python@3.12/3.12.1_1/Frameworks/Python.framework/Versions/3.12/lib/python3.12/re/_parser.py", line 460, in _parse_sub
    itemsappend(_parse(source, state, verbose, nested + 1,
                ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/opt/homebrew/Cellar/python@3.12/3.12.1_1/Frameworks/Python.framework/Versions/3.12/lib/python3.12/re/_parser.py", line 862, in _parse
    p = _parse_sub(source, state, sub_verbose, nested + 1)
        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/opt/homebrew/Cellar/python@3.12/3.12.1_1/Frameworks/Python.framework/Versions/3.12/lib/python3.12/re/_parser.py", line 460, in _parse_sub
    itemsappend(_parse(source, state, verbose, nested + 1,
                ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/opt/homebrew/Cellar/python@3.12/3.12.1_1/Frameworks/Python.framework/Versions/3.12/lib/python3.12/re/_parser.py", line 862, in _parse
    p = _parse_sub(source, state, sub_verbose, nested + 1)
        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/opt/homebrew/Cellar/python@3.12/3.12.1_1/Frameworks/Python.framework/Versions/3.12/lib/python3.12/re/_parser.py", line 460, in _parse_sub
    itemsappend(_parse(source, state, verbose, nested + 1,
                ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/opt/homebrew/Cellar/python@3.12/3.12.1_1/Frameworks/Python.framework/Versions/3.12/lib/python3.12/re/_parser.py", line 862, in _parse
    p = _parse_sub(source, state, sub_verbose, nested + 1)
        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/opt/homebrew/Cellar/python@3.12/3.12.1_1/Frameworks/Python.framework/Versions/3.12/lib/python3.12/re/_parser.py", line 460, in _parse_sub
    itemsappend(_parse(source, state, verbose, nested + 1,
                ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/opt/homebrew/Cellar/python@3.12/3.12.1_1/Frameworks/Python.framework/Versions/3.12/lib/python3.12/re/_parser.py", line 840, in _parse
    raise source.error('global flags not at the start '
re.error: global flags not at the start of the expression at position 5

Expected behaviour
This cron expression should pass on Python 3.12

Additional context
There were changes to the re module in 3.12: https://docs.python.org/3/library/re.html. It is possible one of those changes has caused an issue.

[grumBit]

Hi @ojc-orchestra, thank you for reporting the problems. I'll take a look.

[grumBit]

Hi @ojc-orchestra, I think this is now fixed. I needed to make a change to the regexp syntax I was using for ignoring case. I'm guessing my original syntax wasn't entirely correct and 3.12 became less forgiving than previous versions. Also, thank you for the detailed bug info, it made it easier to investigate.