--- a/tests/test-narrow-patch.t	Mon Jan 29 18:16:23 2018 -0500
+++ b/tests/test-narrow-patch.t	Thu Feb 01 17:19:41 2018 -0500
@@ -1,6 +1,14 @@
+#testcases flat tree
 
   $ . "$TESTDIR/narrow-library.sh"
 
+#if tree
+  $ cat << EOF >> $HGRCPATH
+  > [experimental]
+  > treemanifest = 1
+  > EOF
+#endif
+
 create full repo
 
   $ hg init master