refs: handle "refs/bisect/" in `loose_fill_ref_dir()`

That "refs/bisect/" has to be handled specially when filling the
ref_cache for loose references is a peculiarity of the files backend,
and the ref-cache code shouldn't need to know about it. So move this
code to the callback function, `loose_fill_ref_dir()`.

Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

refs/files-backend.c

@@ -507,6 +507,21 @@ static void loose_fill_ref_dir(struct ref_store *ref_store,
 	strbuf_release(&refname);
 	strbuf_release(&path);
 	closedir(d);
+
+	/*
+	 * Manually add refs/bisect, which, being per-worktree, might
+	 * not appear in the directory listing for refs/ in the main
+	 * repo.
+	 */
+	if (!strcmp(dirname, "refs/")) {
+		int pos = search_ref_dir(dir, "refs/bisect/", 12);
+
+		if (pos < 0) {
+			struct ref_entry *child_entry = create_dir_entry(
+					dir->cache, "refs/bisect/", 12, 1);
+			add_entry_to_dir(dir, child_entry);
+		}
+	}
 }
 
 static struct ref_dir *get_loose_refs(struct files_ref_store *refs)

refs/ref-cache.c

@@ -26,22 +26,6 @@ struct ref_dir *get_ref_dir(struct ref_entry *entry)
 			die("BUG: incomplete ref_store without fill_ref_dir function");
 
 		dir->cache->fill_ref_dir(dir->cache->ref_store, dir, entry->name);
-
-		/*
-		 * Manually add refs/bisect, which, being
-		 * per-worktree, might not appear in the directory
-		 * listing for refs/ in the main repo.
-		 */
-		if (!strcmp(entry->name, "refs/")) {
-			int pos = search_ref_dir(dir, "refs/bisect/", 12);
-			if (pos < 0) {
-				struct ref_entry *child_entry;
-				child_entry = create_dir_entry(dir->cache,
-							       "refs/bisect/",
-							       12, 1);
-				add_entry_to_dir(dir, child_entry);
-			}
-		}
 		entry->flag &= ~REF_INCOMPLETE;
 	}
 	return dir;