copy from tests/test-undo
copy to tests/test-rollback
--- a/tests/test-undo
+++ b/tests/test-rollback
@@ -9,7 +9,7 @@ hg commit -m "test" -d "1000000 0"
 hg verify
 hg parents
 hg status
-hg undo
+hg rollback
 hg verify
 hg parents
 hg status