mercurial/merge.py

--- a/mercurial/merge.py	Fri Nov 20 16:17:54 2015 -0800
+++ b/mercurial/merge.py	Fri Nov 20 16:18:51 2015 -0800
@@ -504,6 +504,11 @@
                     merged += 1
         return updated, merged, removed
 
+    def unresolvedcount(self):
+        """get unresolved count for this merge (persistent)"""
+        return len([True for f, entry in self._state.iteritems()
+                    if entry[0] == 'u'])
+
 def _checkunknownfile(repo, wctx, mctx, f, f2=None):
     if f2 is None:
         f2 = f