--- a/hgext/states.py	Tue Sep 27 11:25:13 2011 +0200
+++ b/hgext/states.py	Wed Sep 28 12:35:55 2011 +0200
@@ -1038,35 +1038,28 @@
 
     def strip(ui, repo, node, backup="all"):
         cl = repo.changelog
-
         striprev = cl.rev(node)
         revstostrip = set(cl.descendants(striprev))
         revstostrip.add(striprev)
-        tostrip = set(cl.node(rev) for rev in revstostrip) # XXX stay in nodes?
-
-        baserevstostrip = revstostrip - set(cl.descendants(*revstostrip))
-        basetostrip = set(cl.node(rev) for rev in baserevstostrip) # XXX stay in nodes?
-        newstatesheads = reduce(or_,
-                                (set(cl.parents(n)) for n in basetostrip),
-                                set([]))
-
-        statesheads={} # use this cache as repo.nodestate shall work
-        for nd in newstatesheads:
+        tostrip = set(map(cl.node, revstostrip))
+        # compute the potentially new created states bondaries which are any
+        # parent of the stripped node that are not stripped (may not be heads)
+        newbondaries = set(par for nod in tostrip for par in cl.parents(nod)
+                           if par not in tostrip)
+        # save the current states of newbondaries in a chache as repo.nodestate
+        # must work along the loop. We will use the next loop to add them.
+        statesheads={}
+        for nd in newbondaries:
             state = repo.nodestate(nd)
-            if not state.trackheads:
-                continue
-            statesheads.setdefault(state, set([])).add(nd)
+            if state.trackheads:
+                statesheads.setdefault(state, set([])).add(nd)
 
         for state, heads in repo._statesheads.iteritems():
-            if not state.trackheads:
-                continue
-            heads = set(heads)
-            headstostrip = tostrip & heads
-            heads.difference_update(headstostrip)
-            heads.update(statesheads.get(state, set([])))
-            repo._statesheads[state] = list(heads)
-        _writestateshead(repo) # after ostrip ?
-
+            if state.trackheads:
+                heads = set(heads) - tostrip | statesheads.get(state, set([]))
+                repo._statesheads[state] = list(heads)
+        _writestateshead(repo)
 
         return ostrip(ui, repo, node, backup)
+
     mercurial.repair.strip = strip