diff -r e7c0e5f81367 -r c38eaeb3b45e mercurial/branchmap.py
--- a/mercurial/branchmap.py	Tue Oct 01 00:12:34 2013 +0900
+++ b/mercurial/branchmap.py	Mon Sep 30 15:52:37 2013 +0200
@@ -210,8 +210,8 @@
             if not nodes:
                 droppednodes.extend(nodes)
                 del self[branch]
+
         if ((not self.validfor(repo)) or (self.tipnode in droppednodes)):
-
             # cache key are not valid anymore
             self.tipnode = nullid
             self.tiprev = nullrev