Non-frozen bitarrays appear hashable on Windows installs

[andrew-vant]

I'm not sure what to make of this, but it tripped me up when isinstance(Hashable) unexpectedly returned true for bitarray objects. Example:

Python 3.12.9 (tags/v3.12.9:fdb8142, Feb  4 2025, 15:27:58) [MSC v.1942 64 bit (AMD64)] on win32
Type "help", "copyright", "credits" or "license" for more information.
>>> from bitarray import bitarray
>>> from collections.abc import Hashable
>>> ba = bitarray()
>>> isinstance(ba, Hashable)
True
>>> ba.__hash__
<method-wrapper '__hash__' of bitarray.bitarray object at 0x000001F1A18633C0>
>>> ba.__hash__()
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
TypeError: unhashable type: 'bitarray.bitarray'

The weird part is that it only happens on windows. The isinstance check correctly returns false on linux, and the __hash__ method doesn't exist.

Tested on python 3.12, bitarray 2.9.2 and 3.3.0. [edit: installed on windows via py -m pip install bitarray=={version}, on linux installed from apt)]

[ilanschnell]

That you for reporting this issue. I get the same on Windows using Python 3.7 and the latest bitarray. There is actually a test for this (which is skipped in Windows as well): https://github.com/ilanschnell/bitarray/blob/master/bitarray/test_bitarray.py#L1759

I'm curious what is going on, and will look into it some more. Thanks