t0008: document test_expect_success_multi

diff --git a/t/t3406-rebase-message.sh b/t/t3406-rebase-message.sh
index fe5f936988bc5ec9bbe6d9175ef6e085c422eadc..6898377910f9fce8ccc73fba7b8140dff53d7ec6 100755 (executable)
--- a/t/t3406-rebase-message.sh
+++ b/t/t3406-rebase-message.sh
@@ -62,4 +62,9 @@ test_expect_success 'rebase -n overrides config rebase.stat config' '
         ! grep "^ fileX |  *1 +$" diffstat.txt
 '
 
+test_expect_success 'rebase --onto outputs the invalid ref' '
+       test_must_fail git rebase --onto invalid-ref HEAD HEAD 2>err &&
+       grep "invalid-ref" err
+'
+
 test_done