Clear dict py314

[mamico]

Fix: #218

IMHO in python 3.14 dictionary and/or garbage optimization requires to explicitly clear the dictionary.

Although this change seems to fix the tests in python 3.14 (tested with python 3.14.0b2), I suggest double-checking the change with someone more familiar with the internals of the library to exclude any side effects related to the change

[dataflake]

I ran the latest zope.meta configuration so that the addition of Python 3.14 is reflected everywhere instead of just the GHA version specification. I have no idea why the pypy-3.10 test on Windows is failing while looking for setuptools 78.1.1, that makes no sense.

[dataflake]

After reverting the setuptools version change the tests are turning green again. So there's yet another setuptools issue.

What confuses me about the PyPy build (as a non-expert) is that the C extensions are built and that the build instructions in the cffi_modules argument to setup in setup.py are run, even though cffi is only a dependency for CPython. I thought PyPy code doesn't build or use the C extensions?

[dataflake]

The setuptools issue is a separate problem, the dictionary fix should go ahead. I can't judge if that dictionary clearing has unwanted side effects, though.

[davisagli]

Before this change, you can assign obj.__dict__ to another variable, then call obj._p_deactivate(), and still access the dict items via the other variable. After the change, the dict will be empty even if it's accessed via another reference. I'm not sure if that will cause problems but it seems worth noting.

[jamadden]

Before this change, you can assign obj.__dict__ to another variable, then call obj._p_deactivate(), and still access the dict items via the other variable. After the change, the dict will be empty even if it's accessed via another reference. I'm not sure if that will cause problems but it seems worth noting.

This is how the pure-Python implementation already works, so I believe that should be the expected behaviour:

persistent/src/persistent/persistence.py

Lines 453 to 458 in a5bafe1

	try:
	idict = _OGA(self, '__dict__')
	except AttributeError:
	pass
	else:
	idict.clear()

Relstorage has tests that fail without this change, and which pass with this change and pass in PURE_PYTHON=1. The entire RelStorage test suite passes with this change.

+1 from me, and for getting this merged and released.

[icemac]

Just released in https://pypi.org/project/persistent/6.2/.