docs/diff-options: clarify scope of diff-filter types

diff --git a/t/t0100-previous.sh b/t/t0100-previous.sh
index e0a69402324fed3c2fd7ca9495f5735742766108..58c0b7e9b6d99a6ea8a507da89eb66f3c8780c31 100755 (executable)
--- a/t/t0100-previous.sh
+++ b/t/t0100-previous.sh
@@ -56,5 +56,13 @@ test_expect_success 'merge @{-100} before checking out that many branches yet' '
        test_must_fail git merge @{-100}
 '
 
+test_expect_success 'log -g @{-1}' '
+       git checkout -b last_branch &&
+       git checkout -b new_branch &&
+       echo "last_branch@{0}" >expect &&
+       git log -g --format=%gd @{-1} >actual &&
+       test_cmp expect actual
+'
+
 test_done