# HG changeset patch
# User Siddharth Agarwal <sid0@fb.com>
# Date 1447048598 28800
# Node ID 988d84cc5565183319a50746323129e637fd4759
# Parent  bb0824a1f7c416693ecc59cd5c32e6e6f7d2f5cf
determine_wants: deal with refs being None

Not clear how this is happening, but this should fix it.

Resolves issue #166.

diff -r bb0824a1f7c4 -r 988d84cc5565 hggit/git_handler.py
--- a/hggit/git_handler.py	Sun Nov 08 21:41:52 2015 -0800
+++ b/hggit/git_handler.py	Sun Nov 08 21:56:38 2015 -0800
@@ -1097,6 +1097,8 @@
         graphwalker = self.git.get_graph_walker(heads=haveheads)
 
         def determine_wants(refs):
+            if refs is None:
+                return None
             filteredrefs = self.filter_refs(refs, heads)
             return [x for x in filteredrefs.itervalues() if x not in self.git]