19f286ff

By: Tom Sydney Kerckhove <syd@cs-syd.eu>

ical-recurrence: ignore a ByWeekNo that the year does not have

@
   Note: Assuming a Monday week start, week 53 can only occur when
   Thursday is January 1 or if it is a leap year and Wednesday is
   January 1.
@

fromWeekDateWithStart never fails: it adds 7 * (w - 1) days to the first
day of the first week of the year, so a week number the year does not
have simply lands in the following year.  Nothing downstream checked that
the day was still in the year being expanded.

Guard on the number of weeks in the year instead.  Filtering in
byWeekNoExpand would have been wrong, because an empty result there falls
through to the branch that expands by month and day and would produce an
instance rather than none.

Timeline