diff -r c026547454dd -r 22c42bfbe7ab mercurial/obsutil.py
--- a/mercurial/obsutil.py	Fri Jan 12 11:10:18 2018 +0000
+++ b/mercurial/obsutil.py	Fri Jan 12 11:15:41 2018 +0000
@@ -875,10 +875,10 @@
                                   "%d more"),
 }
 
-def _getfilteredreason(unfilteredrepo, changeid, ctx):
+def _getfilteredreason(repo, changeid, ctx):
     """return a human-friendly string on why a obsolete changeset is hidden
     """
-    successors = successorssets(unfilteredrepo, ctx.node())
+    successors = successorssets(repo, ctx.node())
     fate = _getobsfate(successors)
 
     # Be more precise in case the revision is superseded