mercurial/error.py

--- a/mercurial/error.py	Mon Apr 01 18:48:12 2013 -0300
+++ b/mercurial/error.py	Fri Feb 15 18:07:14 2013 +0900
@@ -27,6 +27,9 @@
     def __str__(self):
         return RevlogError.__str__(self)
 
+class ManifestLookupError(LookupError):
+    pass
+
 class CommandError(Exception):
     """Exception raised on errors in parsing the command line."""