[PATCH v3 0/4] worktree: teach "add" to check out existing branches

[Thomas Gummerer <t.gummerer@xxxxxxxxx>]

Previous rounds are at <20180121120208.12760-1-t.gummerer@xxxxxxxxx>
and <20180204221305.28300-1-t.gummerer@xxxxxxxxx>.  Thanks Duy, Eric
and Junio for the comments on the previous round.

Junio: I know it is the rc period right now, but the topic is also
already queued in 'pu', so I wasn't sure if you prefer me submitting
this now, or after 2.17 is released.  I'm happy to resend this once
2.17 is out if that makes it easier for you.

This round improves the end user facing messages, and factors out a
dwim_branch function as suggested by Duy.

Interdiff below:

diff --git a/builtin/worktree.c b/builtin/worktree.c
index ea420bb90b..b5d273751f 100644
--- a/builtin/worktree.c
+++ b/builtin/worktree.c
@@ -304,8 +304,6 @@ static int add_worktree(const char *path, const char *refname,
 	strbuf_addf(&sb, "%s/commondir", sb_repo.buf);
 	write_file(sb.buf, "../..");
 
-	fprintf(stderr, _("Preparing %s (identifier %s)"), path, name);
-
 	argv_array_pushf(&child_env, "%s=%s", GIT_DIR_ENVIRONMENT, sb_git.buf);
 	argv_array_pushf(&child_env, "%s=%s", GIT_WORK_TREE_ENVIRONMENT, path);
 	cp.git_cmd = 1;
@@ -322,12 +320,12 @@ static int add_worktree(const char *path, const char *refname,
 		goto done;
 
 	if (opts->checkout_existing_branch)
-		fprintf(stderr, _(", checking out existing branch '%s'"),
+		fprintf(stderr, _("checking out branch '%s'"),
 			refname);
 	else if (opts->new_branch)
-		fprintf(stderr, _(", creating new branch '%s'"), opts->new_branch);
+		fprintf(stderr, _("creating branch '%s'"), opts->new_branch);
 
-	fprintf(stderr, _(", setting HEAD to %s"),
+	fprintf(stderr, _("worktree HEAD is now at %s"),
 		find_unique_abbrev(commit->object.oid.hash, DEFAULT_ABBREV));
 
 	strbuf_reset(&sb);
@@ -373,6 +371,32 @@ static int add_worktree(const char *path, const char *refname,
 	return ret;
 }
 
+static const char *dwim_branch(const char *path, struct add_opts *opts)
+{
+	int n;
+	const char *s = worktree_basename(path, &n);
+	const char *branchname = xstrndup(s, n);
+	struct strbuf ref = STRBUF_INIT;
+
+	if (!strbuf_check_branch_ref(&ref, branchname) &&
+	    ref_exists(ref.buf)) {
+		*branch = branchname;
+		opts->checkout_existing_branch = 1;
+		strbuf_release(&ref);
+		UNLEAK(branchname);
+		return branchname;
+	}
+
+	opts->new_branch = branchname;
+	if (guess_remote) {
+		struct object_id oid;
+		const char *remote =
+			unique_tracking_name(opts->new_branch, &oid);
+		return remote;
+	}
+	return NULL;
+}
+
 static int add(int ac, const char **av, const char *prefix)
 {
 	struct add_opts opts;
@@ -425,27 +449,9 @@ static int add(int ac, const char **av, const char *prefix)
 	}
 
 	if (ac < 2 && !opts.new_branch && !opts.detach) {
-		int n;
-		const char *s = worktree_basename(path, &n);
-		const char *branchname = xstrndup(s, n);
-		struct strbuf ref = STRBUF_INIT;
-
-		if (!strbuf_check_branch_ref(&ref, branchname) &&
-		    ref_exists(ref.buf)) {
-			branch = branchname;
-			opts.checkout_existing_branch = 1;
-			UNLEAK(branch);
-		} else {
-			opts.new_branch = branchname;
-			if (guess_remote) {
-				struct object_id oid;
-				const char *remote =
-					unique_tracking_name(opts.new_branch, &oid);
-				if (remote)
-					branch = remote;
-			}
-		}
-		strbuf_release(&ref);
+		const char *dwim_branchname = dwim_branch(path, &opts);
+		if (dwim_branchname)
+			branch = dwim_branchname;
 	}
 
 	if (ac == 2 && !opts.new_branch && !opts.detach) {

Thomas Gummerer (4):
  worktree: improve message when creating a new worktree
  worktree: be clearer when "add" dwim-ery kicks in
  worktree: factor out dwim_branch function
  worktree: teach "add" to check out existing branches

 Documentation/git-worktree.txt |  9 +++--
 builtin/worktree.c             | 60 +++++++++++++++++++++++++---------
 t/t2025-worktree-add.sh        | 15 +++++++--
 3 files changed, 64 insertions(+), 20 deletions(-)

-- 
2.17.0.rc0.231.g781580f06