t1500: ensure current --since= behavior remains

This behavior of git-rev-parse is observed since git 1.8.3.1
at least(*), and likely earlier versions.

At least one git-reliant project in-the-wild relies on this
current behavior of git-rev-parse being able to handle multiple
--since= arguments without squeezing identical results together.
So add a test to prevent the potential for regression in
downstream projects.

(*) 1.8.3.1 the version packaged for CentOS 7.x

Signed-off-by: Eric Wong <e@80x24.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/t/t1500-rev-parse.sh b/t/t1500-rev-parse.sh
index 408b97d5af9551f91a86e70c6c37b912719bfd15..56549efc96d41a00546b6c53097aaf1e19364b81 100755 (executable)
--- a/t/t1500-rev-parse.sh
+++ b/t/t1500-rev-parse.sh
@@ -185,4 +185,19 @@ test_expect_success 'showing the superproject correctly' '
        test_cmp expect out
 '
 
+# at least one external project depends on this behavior:
+test_expect_success 'rev-parse --since= unsqueezed ordering' '
+       x1=--since=1970-01-01T00:00:01Z &&
+       x2=--since=1970-01-01T00:00:02Z &&
+       x3=--since=1970-01-01T00:00:03Z &&
+       git rev-parse $x1 $x1 $x3 $x2 >actual &&
+       cat >expect <<-EOF &&
+       --max-age=1
+       --max-age=1
+       --max-age=3
+       --max-age=2
+       EOF
+       test_cmp expect actual
+'
+
 test_done