sha1_name: tweak @{-N} lookup

diff --git a/builtin-checkout.c b/builtin-checkout.c
index c2c05613b67d7cc8bd3500bdbca4fc3533afaeee..dc1de06279e2fcdb945e3ec5bdcd0a6f7d06e51b 100644 (file)
--- a/builtin-checkout.c
+++ b/builtin-checkout.c
@@ -361,8 +361,16 @@ struct branch_info {
 static void setup_branch_path(struct branch_info *branch)
 {
        struct strbuf buf = STRBUF_INIT;
-       strbuf_addstr(&buf, "refs/heads/");
-       strbuf_addstr(&buf, branch->name);
+       int ret;
+
+       if ((ret = interpret_nth_last_branch(branch->name, &buf))
+           && ret == strlen(branch->name)) {
+               branch->name = xstrdup(buf.buf);
+               strbuf_splice(&buf, 0, 0, "refs/heads/", 11);
+       } else {
+               strbuf_addstr(&buf, "refs/heads/");
+               strbuf_addstr(&buf, branch->name);
+       }
        branch->path = strbuf_detach(&buf, NULL);
 }
 
@@ -681,8 +689,8 @@ int cmd_checkout(int argc, const char **argv, const char *prefix)
                argv++;
                argc--;
 
+               new.name = arg;
                if ((new.commit = lookup_commit_reference_gently(rev, 1))) {
-                       new.name = arg;
                        setup_branch_path(&new);
                        if (resolve_ref(new.path, rev, 1, NULL))
                                new.commit = lookup_commit_reference(rev);