t7800-difftool.sh: Simplify the --extcmd test

diff --git a/builtin-rerere.c b/builtin-rerere.c
index 343d6cde48266d63c0aa6826b973e55b48820745..2be9ffb77b38ae687537f3599c9d11e3fbc026a9 100644 (file)
--- a/builtin-rerere.c
+++ b/builtin-rerere.c
@@ -48,6 +48,8 @@ static void garbage_collect(struct string_list *rr)
 
        git_config(git_rerere_gc_config, NULL);
        dir = opendir(git_path("rr-cache"));
+       if (!dir)
+               die_errno("unable to open rr-cache directory");
        while ((e = readdir(dir))) {
                if (is_dot_or_dotdot(e->d_name))
                        continue;