[PATCH 10/16] worktree: make branch creation distinct from worktree population

[Eric Sunshine <sunshine@sunshineco.com>]

The plan is eventually to populate the new worktree via "git reset
--hard" rather than "git checkout". Thus, rather than piggybacking on
git-checkout's -b/-B ability to create a new branch at checkout time,
git-worktree will need to do so itself.

Signed-off-by: Eric Sunshine <sunshine@sunshineco.com>
---

I considered calling branch-related API, such as create_branch(),
directly, however, git-branch provides extra value which may be useful
in the future (such as when --track and --orphan get added to
git-worktree), so it seemed wise to re-use git-branch's implementation
rather than duplicating the functionality. If this proves the wrong
choice, then the series can either be re-rolled or follow-on patches can
address the issue.

 builtin/worktree.c | 17 ++++++++++++++---
 1 file changed, 14 insertions(+), 3 deletions(-)

diff --git a/builtin/worktree.c b/builtin/worktree.c
index cd06bf5..9be1c74 100644
--- a/builtin/worktree.c
+++ b/builtin/worktree.c
@@ -314,12 +314,23 @@ static int add(int ac, const char **av, const char *prefix)
 		opts.new_branch = xstrndup(s, n);
 	}
 
+	if (opts.new_branch) {
+		struct child_process cp;
+		memset(&cp, 0, sizeof(cp));
+		cp.git_cmd = 1;
+		argv_array_push(&cp.args, "branch");
+		if (opts.force_new_branch)
+			argv_array_push(&cp.args, "--force");
+		argv_array_push(&cp.args, opts.new_branch);
+		argv_array_push(&cp.args, branch);
+		if (run_command(&cp))
+			return -1;
+		branch = opts.new_branch;
+	}
+
 	argv_array_push(&cmd, "checkout");
 	if (opts.force)
 		argv_array_push(&cmd, "--ignore-other-worktrees");
-	if (opts.new_branch)
-		argv_array_pushl(&cmd, opts.force_new_branch ? "-B" : "-b",
-				 opts.new_branch, NULL);
 	if (opts.detach)
 		argv_array_push(&cmd, "--detach");
 	argv_array_push(&cmd, branch);
-- 
2.5.0.rc1.201.ga12d9f8