--- a/tests/test-copy.t	Tue Sep 20 10:03:50 2016 -0500
+++ b/tests/test-copy.t	Mon Sep 19 17:14:43 2016 -0400
@@ -224,6 +224,9 @@
 foo was clean:
   $ hg st -AC foo
   C foo
+Trying to copy on top of an existing file fails,
+  $ hg copy -A bar foo
+  foo: not overwriting - file exists
 but it's considered modified after a copy --after --force
   $ hg copy -Af bar foo
   $ hg st -AC foo