--- a/tests/test-convert-clonebranches.t	Thu Jun 15 14:22:39 2017 -0400
+++ b/tests/test-convert-clonebranches.t	Tue Jun 20 09:45:02 2017 -0400
@@ -40,7 +40,7 @@
 convert
 
   $ hg convert -v --config convert.hg.clonebranches=1 source dest |
-  >     python filter.py
+  >     $PYTHON filter.py
   3 adda
   2 changea
   1 addb
@@ -73,7 +73,7 @@
 incremental conversion
 
   $ hg convert -v --config convert.hg.clonebranches=1 source dest |
-  >     python filter.py
+  >     $PYTHON filter.py
   2 c1
   pulling from branch0 into branch1
   4 changesets found