From cc3129dd65b455eb274e1437db87bd235620fffd Mon Sep 17 00:00:00 2001
From: helmutm <helmutm@fd906abe-77d9-0310-91a1-e0d9ade77398>
Date: Tue, 11 Nov 2008 11:45:15 +0000
Subject: [PATCH] avoid duplicates when adding to a parent relation set

git-svn-id: svn://svn.cy55.de/Zope3/src/loops/trunk@2977 fd906abe-77d9-0310-91a1-e0d9ade77398
---
 common.py | 1 +
 1 file changed, 1 insertion(+)

diff --git a/common.py b/common.py
index be4bd69..d4fd906 100644
--- a/common.py
+++ b/common.py
@@ -309,6 +309,7 @@ class ParentRelationSet(RelationSet):
     def add(self, related, order=0, relevance=1.0):
         if isinstance(related, AdapterBase):
             related = related.context
+        self.context.deassignParent(related, [self.predicate])
         self.context.assignParent(related, self.predicate, order, relevance)
 
     def remove(self, related):