worktree: add --[no-]track option to the add subcommand

Currently 'git worktree add' sets up tracking branches if '<branch>' is
a remote tracking branch, and doesn't set them up otherwise, as is the
default for 'git branch'.

This may or may not be what the user wants.  Allow overriding this
behaviour with a --[no-]track flag that gets passed through to 'git
branch'.

We already respect branch.autoSetupMerge, as 'git worktree' just calls
'git branch' internally.

Signed-off-by: Thomas Gummerer <t.gummerer@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

1 files changed, 51 insertions, 0 deletions

diff --git a/t/t2025-worktree-add.sh b/t/t2025-worktree-add.sh
index b5c47ac..72e8b62 100755
--- a/t/t2025-worktree-add.sh
+++ b/t/t2025-worktree-add.sh
@@ -313,5 +313,56 @@ test_expect_success 'checkout a branch under bisect' '
 test_expect_success 'rename a branch under bisect not allowed' '
 	test_must_fail git branch -M under-bisect bisect-with-new-name
 '
+# Is branch "refs/heads/$1" set to pull from "$2/$3"?
+test_branch_upstream () {
+	printf "%s\n" "$2" "refs/heads/$3" >expect.upstream &&
+	{
+		git config "branch.$1.remote" &&
+		git config "branch.$1.merge"
+	} >actual.upstream &&
+	test_cmp expect.upstream actual.upstream
+}
+
+test_expect_success '--track sets up tracking' '
+	test_when_finished rm -rf track &&
+	git worktree add --track -b track track master &&
+	test_branch_upstream track . master
+'
+
+# setup remote repository $1 and repository $2 with $1 set up as
+# remote.  The remote has two branches, master and foo.
+setup_remote_repo () {
+	git init $1 &&
+	(
+		cd $1 &&
+		test_commit $1_master &&
+		git checkout -b foo &&
+		test_commit upstream_foo
+	) &&
+	git init $2 &&
+	(
+		cd $2 &&
+		test_commit $2_master &&
+		git remote add $1 ../$1 &&
+		git config remote.$1.fetch \
+			"refs/heads/*:refs/remotes/$1/*" &&
+		git fetch --all
+	)
+}
+
+test_expect_success '--no-track avoids setting up tracking' '
+	test_when_finished rm -rf repo_upstream repo_local foo &&
+	setup_remote_repo repo_upstream repo_local &&
+	(
+		cd repo_local &&
+		git worktree add --no-track -b foo ../foo repo_upstream/foo
+	) &&
+	(
+		cd foo &&
+		test_must_fail git config "branch.foo.remote" &&
+		test_must_fail git config "branch.foo.merge" &&
+		test_cmp_rev refs/remotes/repo_upstream/foo refs/heads/foo
+	)
+'
 
 test_done