--- a/hgext/convert/common.py	Thu Mar 15 23:02:31 2012 +0000
+++ b/hgext/convert/common.py	Fri Mar 16 17:42:21 2012 -0500
@@ -418,6 +418,8 @@
 
 def parsesplicemap(path):
     """Parse a splicemap, return a child/parents dictionary."""
+    if not path:
+        return {}
     m = {}
     try:
         fp = open(path, 'r')