--- a/tests/test-merge-symlinks.t	Thu Jun 15 14:22:39 2017 -0400
+++ b/tests/test-merge-symlinks.t	Tue Jun 20 09:45:02 2017 -0400
@@ -36,7 +36,7 @@
 Merge them and display *_ISLINK vars
 merge heads
 
-  $ hg merge --tool="python ../echo.py"
+  $ hg merge --tool="$PYTHON ../echo.py"
   merging l
   HG_FILE l
   HG_MY_ISLINK 1
@@ -52,7 +52,7 @@
   $ hg up -C 2
   1 files updated, 0 files merged, 1 files removed, 0 files unresolved
   $ hg copy l l2
-  $ HGMERGE="python ../echo.py" hg up 3
+  $ HGMERGE="$PYTHON ../echo.py" hg up 3
   merging l2
   HG_FILE l2
   HG_MY_ISLINK 1