submodule: add a helper to check if it is safe to write to .gitmodules

diff --git a/builtin/write-tree.c b/builtin/write-tree.c
index c9d3c544e79f46bab9e5fd50079d1bb574b722f2..cdcbf8264e8c6e9b56977b99ad28160754d8fb7c 100644 (file)
--- a/builtin/write-tree.c
+++ b/builtin/write-tree.c
@@ -24,9 +24,8 @@ int cmd_write_tree(int argc, const char **argv, const char *unused_prefix)
        struct option write_tree_options[] = {
                OPT_BIT(0, "missing-ok", &flags, N_("allow missing objects"),
                        WRITE_TREE_MISSING_OK),
-               { OPTION_STRING, 0, "prefix", &prefix, N_("<prefix>/"),
-                 N_("write tree object for a subdirectory <prefix>") ,
-                 PARSE_OPT_LITERAL_ARGHELP },
+               OPT_STRING(0, "prefix", &prefix, N_("<prefix>/"),
+                          N_("write tree object for a subdirectory <prefix>")),
                { OPTION_BIT, 0, "ignore-cache-tree", &flags, NULL,
                  N_("only useful for debugging"),
                  PARSE_OPT_HIDDEN | PARSE_OPT_NOARG, NULL,