Force-with-lease and new branches

From: John Keeping <john@keeping.me.uk>
Date: May 7, 2016, 18:09 UTC
Message-ID: <20160507180914.GR14612@serenity.lan>

I've noticed a slightly annoying behaviour of git-push's --force-with-lease option around branch creation.

I'd like to be able to do:

	git push --force-with-lease origin refs/heads/jk/*

to push out a load of topic branches safely in case I've switched client machines and forgotten to pull, but for newly-created branches this fails with "stale-info", which seems to be intentional via the expect_old_no_trackback field in struct ref.

However, if I use the explicit --force-with-lease syntax with the null hash then the push does succeed. I've added a couple of tests to t5533 which demonstrate this in a patch below - the first one fails but the second passes.

It looks like this has been the case since the first version of what would become --force-with-lease [1] and I can't find any discussion around this particular behaviour in the three versions of that patch set I found on Gmane [2], [3], [4].

So my questions are: what will break if we decide to treat "no remote tracking branch" as "new branch" and is that a reasonable thing to do?

[1] http://article.gmane.org/gmane.comp.version-control.git/229992 [2] http://article.gmane.org/gmane.comp.version-control.git/229430 [3] http://article.gmane.org/gmane.comp.version-control.git/230142 [4] http://article.gmane.org/gmane.comp.version-control.git/231021

-- >8 --

diff --git a/t/t5533-push-cas.sh b/t/t5533-push-cas.sh
index c732012..ad9e06f 100755
--- a/t/t5533-push-cas.sh
+++ b/t/t5533-push-cas.sh
@@ -191,4 +191,28 @@ test_expect_success 'cover everything with default force-with-lease (allowed)' '
 	test_cmp expect actual
 '
 
+test_expect_success 'new branch covered by force-with-lease' '
+	setup_srcdst_basic &&
+	(
+		cd dst &&
+		git branch branch master &&
+		git push --force-with-lease=branch origin branch
+	) &&
+	git ls-remote dst refs/heads/branch >expect &&
+	git ls-remote src refs/heads/branch >actual &&
+	test_cmp expect actual
+'
+
+test_expect_success 'new branch with explicit force-with-lease' '
+	setup_srcdst_basic &&
+	(
+		cd dst &&
+		git branch branch master &&
+		git push --force-with-lease=branch:0000000000000000000000000000000000000000 origin branch
+	) &&
+	git ls-remote dst refs/heads/branch >expect &&
+	git ls-remote src refs/heads/branch >actual &&
+	test_cmp expect actual
+'
+
 test_done