--- a/hgext3rd/topic/stack.py	Fri Sep 01 15:09:59 2017 +0530
+++ b/hgext3rd/topic/stack.py	Fri Sep 15 22:48:55 2017 +0530
@@ -169,7 +169,10 @@
 
     @util.propertycache
     def branches(self):
-        return sorted(set(self._repo[r].branch() for r in self._revs))
+        branches = sorted(set(self._repo[r].branch() for r in self._revs))
+        if not branches:
+            branches = set([self._repo[None].branch()])
+        return branches
 
 def labelsgen(prefix, labelssuffix):
     """ Takes a label prefix and a list of suffixes. Returns a string of the prefix