Don't reassign cls.__new__ for Python 3.10+

[cdce8p]

I've started testing Home Assistant with Python 3.12. One common error is

TypeError: int() can't convert non-string with explicit base

After some investigation I tracked it back to zigpy-znp and indeed, running the test suite results in this error

ImportError while loading conftest '/usr/src/tests/conftest.py'.
tests/conftest.py:27: in <module>
    import zigpy_znp.config as conf
zigpy_znp/config.py:23: in <module>
    from zigpy_znp.commands.util import LEDMode
zigpy_znp/commands/__init__.py:1: in <module>
    from .af import AF
zigpy_znp/commands/af.py:28: in <module>
    class AF(t.CommandsBase, subsystem=t.Subsystem.AF):
zigpy_znp/types/commands.py:192: in __new__
    .with_id(definition.command_id)
zigpy_znp/types/commands.py:122: in with_id
    return type(self)(self & 0x00FF | (value & 0xFF) << 8)
zigpy_znp/types/commands.py:98: in __new__
    instance = super().__new__(cls, value)
zigpy_znp/types/basic.py:48: in __new__
    instance = super().__new__(cls, *args, **kwargs)
E   TypeError: int() can't convert non-string with explicit base

It can be reproduced by executing just

from zigpy_znp.types.commands import CommandHeader
CommandHeader().with_id(4)

It is likely related to a change in cpython regarding reassignments of cls.__new__ and super(), see python/cpython#106917.

As it turns out though, the reassignment isn't actually needed anymore. The tests added in 72402da pass for Python 3.10.0+ without it. Likely a side effect of python/cpython#26658.

The complete code I used to validate this change (tested with Python 3.8 - 3.12.0b4)

import enum
import sys


class FixedIntType(int):
    _signed: bool
    _size: bool

    def __new__(cls, *args, **kwargs):
        if getattr(cls, "_signed", None) is None or getattr(cls, "_size", None) is None:
            raise TypeError(f"{cls} is abstract and cannot be created")

        print(f"=> {cls}, {args=}")
        instance = super().__new__(cls, *args, **kwargs)
        return instance

    def __init_subclass__(cls, signed=None, size=None) -> None:
        super().__init_subclass__()
        if signed is not None:
            cls._signed = signed

        if size is not None:
            cls._size = size

        print(cls.__dict__)
        if sys.version_info < (3, 10):
            if "__new__" not in cls.__dict__:
                cls.__new__ = cls.__new__
                print(cls.__dict__)


class uint_t(FixedIntType, signed=False):
    pass

class uint8_t(uint_t, size=1):
    pass

class uint16_t(uint_t, size=2):
    pass


class CustomInt(uint16_t):
    def __new__(cls, value: int = 0):
        instance = super().__new__(cls, value)
        return instance

    def with_id(self, value: int):
        return type(self)(self & 0x00FF | (value & 0xFF) << 8)

CustomInt().with_id(4)



class enum_uint(uint8_t, enum.Enum):
    pass

class AddrMode(enum_uint):
    """Address mode."""

    NOT_PRESENT = 0x00
    Group = 0x01
    NWK = 0x02
    IEEE = 0x03

    Broadcast = 0x0F

[puddly]

Thanks for the PR! Could you run it through the pre-commit hooks and push a commit to fix the lint errors?

pip install pre-commit
pre-commit install
pre-commit run --files zigpy_znp/types/basic.py

You can also make a whitespace-only change and the hook will run automatically upon commit to correct things.

[codecov]

Codecov Report

Patch coverage: 100.00% and project coverage change: +0.05 🎉

Comparison is base (686cb6c) 98.46% compared to head (fefb3a0) 98.52%.

❗ Current head fefb3a0 differs from pull request most recent head 1f160f3. Consider uploading reports for the commit 1f160f3 to get more accurate results

Additional details and impacted files

@@            Coverage Diff             @@
##              dev     #219      +/-   ##
==========================================
+ Coverage   98.46%   98.52%   +0.05%     
==========================================
  Files          43       43              
  Lines        3785     3787       +2     
==========================================
+ Hits         3727     3731       +4     
+ Misses         58       56       -2     

Impacted Files	Coverage Δ
zigpy_znp/types/basic.py	100.00% <100.00%> (ø)

... and 1 file with indirect coverage changes

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