[Davical-general] Overlap calculation

[Ben H. <0x6...@gm...>]

Hi,

I was wondering in 1.1.6 why

SELECT rrule_event_overlaps(
'2018-01-23 18:00:01'::timestamp, -- dtstart
'2018-01-25 00:00:00'::timestamp, -- dtend
null, -- rrule
'2018-01-22 12:00:00'::timestamp, -- mindate
'2018-01-22 12:00:00'::timestamp -- maxdate
);

would return true, whereas setting dtstart to a minute beforehand returns false:

SELECT rrule_event_overlaps(
'2018-01-23 18:00:00'::timestamp, -- dtstart
'2018-01-25 00:00:00'::timestamp, -- dtend
null, -- rrule
'2018-01-22 12:00:00'::timestamp, -- mindate
'2018-01-22 12:00:00'::timestamp -- maxdate
);

Looking into the implementation, there is a short circuit:

IF repeatrule IS NULL THEN
  RETURN (dtstart <= maxdate AND base_date >= mindate);
END IF;

In this particular constellation, this function flips when dtstart
goes from 2018-01-23 18:00:00 to 2018-01-23 18:00:01.

Is this behavior expected?

Thanks in advance,

Ben