get_short_sha1: make default disambiguation configurable

diff --git a/t/t6026-merge-attr.sh b/t/t6026-merge-attr.sh
index 3d28c786878b385a09c72ed23836a5e6e1fece78..7a6e33e6732eaf69e298b56729ba4ead9ffaee0e 100755 (executable)
--- a/t/t6026-merge-attr.sh
+++ b/t/t6026-merge-attr.sh
@@ -181,11 +181,13 @@ test_expect_success 'up-to-date merge without common ancestor' '
        )
 '
 
-test_expect_success !MINGW 'custom merge does not lock index' '
+test_expect_success 'custom merge does not lock index' '
        git reset --hard anchor &&
        write_script sleep-one-second.sh <<-\EOF &&
                sleep 1 &
+               echo $! >sleep.pid
        EOF
+       test_when_finished "kill \$(cat sleep.pid)" &&
 
        test_write_lines >.gitattributes \
                "* merge=ours" "text merge=sleep-one-second" &&