[Checkins] [zopefoundation/persistent] c4116a: new_ghost doesn't clear object state, preserving _...

[GitHub]

  Branch: refs/heads/new_ghost_doesnt_clear_newargs
  Home:   https://github.com/zopefoundation/persistent
  Commit: c4116ac1345b3ae690590b4455e927c3ae3728ad
      https://github.com/zopefoundation/persistent/commit/c4116ac1345b3ae690590b4455e927c3ae3728ad
  Author: Jason Madden <jamadden at gmail.com>
  Date:   2016-10-28 (Fri, 28 Oct 2016)

  Changed paths:
    M persistent/persistence.py
    M persistent/picklecache.py

  Log Message:
  -----------
  new_ghost doesn't clear object state, preserving __getnewargs__ values.


  Commit: ac51dff1512477b4afa5a7f760327730a198053d
      https://github.com/zopefoundation/persistent/commit/ac51dff1512477b4afa5a7f760327730a198053d
  Author: Kirill Smelkov <kirr at nexedi.com>
  Date:   2016-10-28 (Fri, 28 Oct 2016)

  Changed paths:
    M persistent/persistence.py
    M persistent/tests/test_persistence.py

  Log Message:
  -----------
  py/deactivate vs slots: A slot variable could not be initialized at all

fe2219f4 (On deactivate release in-slots objects too) started to release
objects from slotted variables but was not careful enough while doing so: we
have to be careful while deleting as for unset variables it will raise
AttributeError:

    class C(object):
  __slots__ = ['aaa', 'unset']
   def __init__(self, aaa):
      self.aaa = 1

    c = C(111)
    del c.aaa
    del c.unset

    Traceback (most recent call last):
      File "y.py", line 9, in <module>
  del c.unset
    AttributeError: unset

Caught by preparing fix for https://github.com/zopefoundation/persistent/pull/44#issuecomment-256768600

C version already have this protection in the original fe2219f4 patch:

    +            if (PyObject_GenericSetAttr((PyObject *)self, name, NULL) < 0)
    +                /* delattr of non-set slot will raise AttributeError - we
    +                 * simply ignore. */
    +                PyErr_Clear();


  Commit: 7fb761e0a86ad56f2b7dfe4c244c19fd6535a61c
      https://github.com/zopefoundation/persistent/commit/7fb761e0a86ad56f2b7dfe4c244c19fd6535a61c
  Author: Jason Madden <jamadden at gmail.com>
  Date:   2016-10-28 (Fri, 28 Oct 2016)

  Changed paths:
    M persistent/persistence.py
    M persistent/picklecache.py
    M persistent/tests/test_persistence.py
    M persistent/tests/test_picklecache.py

  Log Message:
  -----------
  Don't clear the slots/dict when adding a new_ghost to Python
PickleCache.

Fixes #49.

Unfortunately, this doesn't fix the whole problem, because
_p_deactivate() still clears them, and so we lose what we set in __new__.


Compare: https://github.com/zopefoundation/persistent/compare/c4116ac1345b^...7fb761e0a86a