--- a/mercurial/merge.py	Tue Nov 17 17:04:53 2015 -0800
+++ b/mercurial/merge.py	Tue Nov 17 13:55:30 2015 -0800
@@ -83,6 +83,12 @@
         ms.reset(node, other)
         return ms
 
+    @staticmethod
+    def read(repo):
+        """Initialize the merge state, reading it from disk."""
+        ms = mergestate(repo)
+        return ms
+
     def __init__(self, repo):
         self._repo = repo
         self._dirty = False