Don't bug out in gnus-icalendar when there no recurring event

* lisp/gnus/gnus-icalendar.el
(gnus-icalendar-event:recurring-days): Fix previous patch
(bug#43038) -- don't bug out when there's no recurring event.

diff --git a/lisp/gnus/gnus-icalendar.el b/lisp/gnus/gnus-icalendar.el
index f13d4dec0145ad5c440058f38a1ffe94070c9729..da41b08c7175cb763431780de523271873cbf4c4 100644 (file)
--- a/lisp/gnus/gnus-icalendar.el
+++ b/lisp/gnus/gnus-icalendar.el
@@ -148,7 +148,7 @@
                        ("TH" . 4)
                        ("FR" . 5)
                        ("SA" . 6))))
-    (when (string-match "BYDAY=\\([^;]+\\)" rrule)
+    (when (and rrule (string-match "BYDAY=\\([^;]+\\)" rrule))
       (let ((bydays (split-string (match-string 1 rrule) ",")))
         (seq-map
          (lambda (x) (cdr (assoc x weekday-map)))