builtin rebase: only store fully-qualified refs in `options.head_name`

diff --git a/builtin/rebase.c b/builtin/rebase.c
index d45f8f9008182ff39f057dae4a4d5e6eb52324a7..afc75fe7314e6d23f4c9c36138eede77064d804c 100644 (file)
--- a/builtin/rebase.c
+++ b/builtin/rebase.c
@@ -169,7 +169,8 @@ static int run_specific_rebase(struct rebase_options *opts)
        add_var(&script_snippet, "upstream_name", opts->upstream_name);
        add_var(&script_snippet, "upstream",
                                 oid_to_hex(&opts->upstream->object.oid));
-       add_var(&script_snippet, "head_name", opts->head_name);
+       add_var(&script_snippet, "head_name",
+               opts->head_name ? opts->head_name : "detached HEAD");
        add_var(&script_snippet, "orig_head", oid_to_hex(&opts->orig_head));
        add_var(&script_snippet, "onto", oid_to_hex(&opts->onto->object.oid));
        add_var(&script_snippet, "onto_name", opts->onto_name);
@@ -251,6 +252,9 @@ static int reset_head(struct object_id *oid, const char *action,
                *old_orig = NULL, oid_old_orig;
        int ret = 0;
 
+       if (switch_to_branch && !starts_with(switch_to_branch, "refs/"))
+               BUG("Not a fully qualified branch: '%s'", switch_to_branch);
+
        if (hold_locked_index(&lock, LOCK_REPORT_ON_ERROR) < 0)
                return -1;
 
@@ -558,7 +562,7 @@ int cmd_rebase(int argc, const char **argv, const char *prefix)
         * branch_name -- branch/commit being rebased, or
         *                HEAD (already detached)
         * orig_head -- commit object name of tip of the branch before rebasing
-        * head_name -- refs/heads/<that-branch> or "detached HEAD"
+        * head_name -- refs/heads/<that-branch> or NULL (detached HEAD)
         */
        if (argc > 0)
                 die("TODO: handle switch_to");
@@ -575,7 +579,8 @@ int cmd_rebase(int argc, const char **argv, const char *prefix)
                                branch_name = options.head_name;
 
                } else {
-                       options.head_name = xstrdup("detached HEAD");
+                       free(options.head_name);
+                       options.head_name = NULL;
                        branch_name = "HEAD";
                }
                if (get_oid("HEAD", &options.orig_head))