[Question] Getting the error `ValueError: mutable default <class 'cminx.config.InputSettings'> for field input is not allowed: use default_factory`

[dschiller]

Before opening this issue I:

• [x] Checked the documentation for answers
• [x] Looked for similar issues
• [x] Did a quick internet search

When I execute cminx I get the following error:

cminx
Traceback (most recent call last):
  File "/Volumes/K2TB/Work/CMake/tools/develop/.venv/bin/cminx", line 5, in <module>
    from cminx import main
  File "/Volumes/K2TB/Work/CMake/tools/develop/.venv/lib/python3.11/site-packages/cminx/__init__.py", line 38, in <module>
    from .config import config_template, dict_to_settings, Settings
  File "/Volumes/K2TB/Work/CMake/tools/develop/.venv/lib/python3.11/site-packages/cminx/config.py", line 101, in <module>
    @dataclass
     ^^^^^^^^^
  File "/usr/local/Cellar/python@3.11/3.11.2/Frameworks/Python.framework/Versions/3.11/lib/python3.11/dataclasses.py", line 1220, in dataclass
    return wrap(cls)
           ^^^^^^^^^
  File "/usr/local/Cellar/python@3.11/3.11.2/Frameworks/Python.framework/Versions/3.11/lib/python3.11/dataclasses.py", line 1210, in wrap
    return _process_class(cls, init, repr, eq, order, unsafe_hash,
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/local/Cellar/python@3.11/3.11.2/Frameworks/Python.framework/Versions/3.11/lib/python3.11/dataclasses.py", line 958, in _process_class
    cls_fields.append(_get_field(cls, name, type, kw_only))
                      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/local/Cellar/python@3.11/3.11.2/Frameworks/Python.framework/Versions/3.11/lib/python3.11/dataclasses.py", line 815, in _get_field
    raise ValueError(f'mutable default {type(f.default)} for field '
ValueError: mutable default <class 'cminx.config.InputSettings'> for field input is not allowed: use default_factory

CMinx==1.1.0
Python 3.11.2

[dschiller]

With Python 3.8.2 it works.

[ryanmrichard]

I'm going to reopen this issue, but specify the issue as ensure CMinx works with Python 3.11 (we currently test with up to 3.10). Hopefully that takes care of the issue @dschiller saw too.

[AutonomicPerfectionist]

It appears restrictions on dataclass defaults mutability were tightened in 3.11, should be a very simple change to fix. I'll also try to get testing with 3.11 working as well