--- a/hgext3rd/topic/discovery.py	Fri Oct 19 09:02:35 2018 -0700
+++ b/hgext3rd/topic/discovery.py	Sun Oct 21 00:08:27 2018 +0300
@@ -81,9 +81,8 @@
 
         def revbranchcache(self):
             rbc = super(repocls, self).revbranchcache()
-            changelog = self.changelog
 
-            def branchinfo(rev):
+            def branchinfo(rev, changelog=None):
                 branch, close = changelog.branchinfo(rev)
                 if rev in publishedset:
                     return branch, close