Merge branch 'tg/worktree-create-tracking'

The way "git worktree add" determines what branch to create from
where and checkout in the new worktree has been updated a bit.

* tg/worktree-create-tracking:
  add worktree.guessRemote config option
  worktree: add --guess-remote flag to add subcommand
  worktree: make add <path> <branch> dwim
  worktree: add --[no-]track option to the add subcommand
  worktree: add can be created from any commit-ish
  checkout: factor out functions to new lib file

1 files changed, 130 insertions, 0 deletions

diff --git a/t/t2025-worktree-add.sh b/t/t2025-worktree-add.sh
index b5c47ac..6ce9b9c 100755
--- a/t/t2025-worktree-add.sh
+++ b/t/t2025-worktree-add.sh
@@ -313,5 +313,135 @@ 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_expect_success '"add" <path> <non-existent-branch> fails' '
+	test_must_fail git worktree add foo non-existent
+'
+
+test_expect_success '"add" <path> <branch> dwims' '
+	test_when_finished rm -rf repo_upstream repo_dwim foo &&
+	setup_remote_repo repo_upstream repo_dwim &&
+	git init repo_dwim &&
+	(
+		cd repo_dwim &&
+		git worktree add ../foo foo
+	) &&
+	(
+		cd foo &&
+		test_branch_upstream foo repo_upstream foo &&
+		test_cmp_rev refs/remotes/repo_upstream/foo refs/heads/foo
+	)
+'
+
+test_expect_success 'git worktree add does not match remote' '
+	test_when_finished rm -rf repo_a repo_b foo &&
+	setup_remote_repo repo_a repo_b &&
+	(
+		cd repo_b &&
+		git worktree add ../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_a/foo refs/heads/foo
+	)
+'
+
+test_expect_success 'git worktree add --guess-remote sets up tracking' '
+	test_when_finished rm -rf repo_a repo_b foo &&
+	setup_remote_repo repo_a repo_b &&
+	(
+		cd repo_b &&
+		git worktree add --guess-remote ../foo
+	) &&
+	(
+		cd foo &&
+		test_branch_upstream foo repo_a foo &&
+		test_cmp_rev refs/remotes/repo_a/foo refs/heads/foo
+	)
+'
+
+test_expect_success 'git worktree add with worktree.guessRemote sets up tracking' '
+	test_when_finished rm -rf repo_a repo_b foo &&
+	setup_remote_repo repo_a repo_b &&
+	(
+		cd repo_b &&
+		git config worktree.guessRemote true &&
+		git worktree add ../foo
+	) &&
+	(
+		cd foo &&
+		test_branch_upstream foo repo_a foo &&
+		test_cmp_rev refs/remotes/repo_a/foo refs/heads/foo
+	)
+'
+
+test_expect_success 'git worktree --no-guess-remote option overrides config' '
+	test_when_finished rm -rf repo_a repo_b foo &&
+	setup_remote_repo repo_a repo_b &&
+	(
+		cd repo_b &&
+		git config worktree.guessRemote true &&
+		git worktree add --no-guess-remote ../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_a/foo refs/heads/foo
+	)
+'
 
 test_done