--- a/tests/test-backout.t	Wed Jan 27 09:07:28 2016 -0800
+++ b/tests/test-backout.t	Sat Jan 30 18:00:11 2016 +0900
@@ -753,3 +753,10 @@
   $ hg backout --no-commit .
   removing 3
   changeset cccc23d9d68f backed out, don't forget to commit.
+  $ hg revert -aq
+
+--no-commit can't be used with --merge
+
+  $ hg backout --merge --no-commit 2
+  abort: cannot use --merge with --no-commit
+  [255]