return 0;
 }
 
+static int match_placeholder_arg(const char *to_parse, const char *candidate,
+                                const char **end)
+{
+       const char *p;
+
+       if (!(skip_prefix(to_parse, candidate, &p)))
+               return 0;
+       if (*p == ',') {
+               *end = p + 1;
+               return 1;
+       }
+       if (*p == ')') {
+               *end = p;
+               return 1;
+       }
+       return 0;
+}
+
 static size_t format_commit_one(struct strbuf *sb, /* in UTF-8 */
                                const char *placeholder,
                                void *context)
 
        if (skip_prefix(placeholder, "(trailers", &arg)) {
                struct process_trailer_options opts = PROCESS_TRAILER_OPTIONS_INIT;
-               while (*arg == ':') {
-                       if (skip_prefix(arg, ":only", &arg))
-                               opts.only_trailers = 1;
-                       else if (skip_prefix(arg, ":unfold", &arg))
-                               opts.unfold = 1;
+               if (*arg == ':') {
+                       arg++;
+                       for (;;) {
+                               if (match_placeholder_arg(arg, "only", &arg))
+                                       opts.only_trailers = 1;
+                               else if (match_placeholder_arg(arg, "unfold", &arg))
+                                       opts.unfold = 1;
+                               else
+                                       break;
+                       }
                }
                if (*arg == ')') {
                        format_trailers_from_commit(sb, msg + c->subject_off, &opts);
 
 '
 
 test_expect_success ':only and :unfold work together' '
-       git log --no-walk --pretty="%(trailers:only:unfold)" >actual &&
-       git log --no-walk --pretty="%(trailers:unfold:only)" >reverse &&
+       git log --no-walk --pretty="%(trailers:only,unfold)" >actual &&
+       git log --no-walk --pretty="%(trailers:unfold,only)" >reverse &&
        test_cmp actual reverse &&
        {
                grep -v patch.description <trailers | unfold &&