[Zope] Undo problem

[Pascal Peregrina]

Hi,

I have made 2 Zope products.

One of them is a content object that extends PropertyManager.
The  :
+ _update_property
+ _set_property
+ _del_property
methods have been redefined to add a call to my 2nd product, in order to
notify it about the changes.

--- code excerpt ---
def  _del_property(self,id):
 <call to the PropertyManager method>
 try:
  getToolByName(self,'change_tracker').manage_addChange(<params>)
 except:
  pass
-----

I created an object A of this type.

The 2nd product is a tool with a simple PersistentMapping() that store these
changes information.

--- code excerpt ---
def manage_addChange(self,<params>):
	...
	self._changes[<somekey>]=<somevalue> # self._changes is the
PersistentMapping
	self._changes=self._changes #to be sure PersistentMapping is updated
in ZODB
	...
-----

I created an object B of this type.

When I modify properties on A, I get the information added to B.
So I thought eveything was working fine.

Unfortunately, when I undo a change on A (using undo tab in ZMI),
information is not removed from B.

Can someone tell me what I did wrong ?

Thanks a lot.

Pascal


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