Method to check if a supplied date is inside a RRULE

[Sidhesh-naik-cci]

Is there a way to check if a supplied date is inside an RRULE?

[JonasWanke]

Currently, this is only possible by iterating over the returned DateTimes and checking whether they contain that target value. The following code should do exactly that:

final isTargetContainedInRule = recurrenceRule.getAllInstances(
  start: start,
  after: target,
  includeAfter: true,
  before: target,
  includeBefore: true,
).isNotEmpty

This is not really efficient right now. If you want to query multiple dates, you can instead call getAllInstances(…) once for the whole range you're interested in and check the resulting list for your dates.

Also, with #66, iteration over recurrence rules without a count parameter can actually skip to the after value, which can speed this check up.