Problem with Event rrule format

[tyctor]

trying to create recuring event, but export to ical fails:

event = icalendar.Event()
event.add("rrule", {'FREQ': 'MONTHLY', 'WKST': 'MO', 'BYDAY': '+1TU,+3TU'})
event.to_ical()

...
ValueError: Expected weekday abbrevation, got: +1TU,+3TU

but icalendar validator on https://icalendar.org/validator.html claims that this rrule is valid

[Nicco Kunzmann]

Thanks for reporting this! You would probably expect the event to be created. What would the valid rrule string or ics string look like?

[tyctor]

hi,
valid rrule string should be
RRULE:FREQ=MONTHLY;WKST=MO;BYDAY=+1TU,+3TU

in words
Every month on the 1st Tuesday and 3rd Tuesday

[tyctor]

oh, understand, value must be list

this is ok:

event = icalendar.Event()
event.add("rrule", {'FREQ': 'WEEKLY', 'WKST': 'MO', 'BYDAY': ['+1TU', '+3TU']})
event.to_ical()

b'BEGIN:VEVENT\r\nRRULE:FREQ=WEEKLY;BYDAY=+1TU,+3TU;WKST=MO\r\nEND:VEVENT\r\n'