unicode calls __str__ for acquisition wrapped objects

[Michael Howitz]

unicode(<some_object>) calls the __unicode__ method of the object
but unicode(<some_aq_wrapped_object>) calls __str__

See the following bin/zopectl debug session:

$ bin/zinstance debug
Starting debugger (the name "app" is bound to the top-level Zope object)
>>> import OFS.SimpleItem
>>> class A(OFS.SimpleItem.SimpleItem):
... def __str__(self): return '__str__ called'
... def __unicode__(self): return '__unicode__ called'
...
>>> a = A()
>>> print unicode(a)
__unicode__ called
>>> print unicode(a.__of__(app))
__str__ called
>>> print type(a.__of__(app))
<type 'Acquisition.ImplicitAcquisitionWrapper'>

This happens for Python 2.6 and 2.7 on Zope 2.13.4.

[Michael Howitz (mh-gocept)]

Fix released in 2.13.6.