new file mode 100755
--- /dev/null
+++ b/tests/test-issue619
@@ -0,0 +1,20 @@
+#!/bin/sh
+
+mkdir t
+cd t
+hg init
+echo a > a
+hg ci -Ama -d '1000000000 0'
+echo b > b
+hg branch b
+hg ci -Amb -d '1000000000 0'
+hg co -C 0
+
+echo fast-forward
+hg merge b
+hg ci -Ammerge -d '1000000000 0'
+
+echo bogus fast-forward should fail
+hg merge b
+
+echo done