builtin/am: introduce write_state_*() helper functions

diff --git a/builtin/worktree.c b/builtin/worktree.c
index 04e6d0f92798f32dd10c1e677f3d85760f7dcdc6..6a264ee749221cd6c6bf98ce68790bdec3dd82c5 100644 (file)
--- a/builtin/worktree.c
+++ b/builtin/worktree.c
@@ -5,6 +5,7 @@
 #include "argv-array.h"
 #include "run-command.h"
 #include "sigchain.h"
+#include "refs.h"
 
 static const char * const worktree_usage[] = {
        N_("git worktree add [<options>] <path> <branch>"),
@@ -152,6 +153,25 @@ static void remove_junk_on_signal(int signo)
        raise(signo);
 }
 
+static const char *worktree_basename(const char *path, int *olen)
+{
+       const char *name;
+       int len;
+
+       len = strlen(path);
+       while (len && is_dir_sep(path[len - 1]))
+               len--;
+
+       for (name = path + len - 1; name > path; name--)
+               if (is_dir_sep(*name)) {
+                       name++;
+                       break;
+               }
+
+       *olen = len;
+       return name;
+}
+
 static int add_worktree(const char *path, const char **child_argv)
 {
        struct strbuf sb_git = STRBUF_INIT, sb_repo = STRBUF_INIT;
@@ -165,15 +185,7 @@ static int add_worktree(const char *path, const char **child_argv)
        if (file_exists(path) && !is_empty_dir(path))
                die(_("'%s' already exists"), path);
 
-       len = strlen(path);
-       while (len && is_dir_sep(path[len - 1]))
-               len--;
-
-       for (name = path + len - 1; name > path; name--)
-               if (is_dir_sep(*name)) {
-                       name++;
-                       break;
-               }
+       name = worktree_basename(path, &len);
        strbuf_addstr(&sb_repo,
                      git_path("worktrees/%.*s", (int)(path + len - name), name));
        len = sb_repo.len;
@@ -278,11 +290,17 @@ static int add(int ac, const char **av, const char *prefix)
        ac = parse_options(ac, av, prefix, options, worktree_usage, 0);
        if (new_branch && new_branch_force)
                die(_("-b and -B are mutually exclusive"));
-       if (ac != 2)
+       if (ac < 1 || ac > 2)
                usage_with_options(worktree_usage, options);
 
        path = prefix ? prefix_filename(prefix, strlen(prefix), av[0]) : av[0];
-       branch = av[1];
+       branch = ac < 2 ? "HEAD" : av[1];
+
+       if (ac < 2 && !new_branch && !new_branch_force) {
+               int n;
+               const char *s = worktree_basename(path, &n);
+               new_branch = xstrndup(s, n);
+       }
 
        argv_array_push(&cmd, "checkout");
        if (force)