mercurial/merge.py

--- a/mercurial/merge.py	Tue Nov 17 17:04:32 2015 -0800
+++ b/mercurial/merge.py	Tue Nov 17 17:04:53 2015 -0800
@@ -853,8 +853,7 @@
     """
 
     updated, merged, removed, unresolved = 0, 0, 0, 0
-    ms = mergestate(repo)
-    ms.reset(wctx.p1().node(), mctx.node())
+    ms = mergestate.clean(repo, wctx.p1().node(), mctx.node())
     moves = []
     for m, l in actions.items():
         l.sort()