Re: [Evolution] Daylight savings time

[Milan Crha <mcrha redhat com>]

On Tue, 2019-04-02 at 22:12 +0200, aguador wrote:
> > repeating Andre's above question: what is the calendar type,
> > please?

        Hi,
I'm sorry, but let's try for the third time: what is the calendar type,
please? It can be On This Computer, CalDAV, Exchange Web Services, ...

> Daniel is correct (and of later and I assume Evo creation); 

It has set:
DTSTART;TZID=/freeassociation.sourceforge.net/Europe/Madrid:
 20190406T090000
DTEND;TZID=/freeassociation.sourceforge.net/Europe/Madrid:
 20190406T100000
thus the timezone is specified there.

> Luis_Ignacio has an hour added.

It has set:
DTSTART:20190402T090000
DTEND:20190402T100000
without any timezone information. These are so called floating times,
which are shown at the same time in whatever timezone the user uses.
Evolution doesn't support floating times for editing yet [1]. Evolution
supports them when showing, only the editor shows a wrong timezone in
those cases, which I believe is the reason why you thought the timezone
is set properly - because Evolution's editor lied to you. A workaround
is to edit the series in Evolution, add a letter into the Summary, then
delete it (which lets you save the series) and save it and propagate
the change into the all instances. It'll add the correct timezone
information into the event.

> The second, which is wrong, shows a start time for 9.00, while the
> one from the week before shows the correct start time of 8.00.

Right, the above DTSTART/DTEND is from the later .ics, showing the 9:00
start, while the former has:
DTSTART:20190326T080000
DTEND:20190326T090000

> So the Android app is likely the root of this evil?

Well, saving times with a floating time can be useful in some cases,
but when one needs to setup a meeting with people in different
timezones then the floating time is useless, thus yes, it's safer to
specify the time zone. I do not know whom to blame.

There is one interesting thing about the broken event. Usually
generated recurrence doesn't change the floating time part, as far as I
know, by the timezone offset (as I tested it here), thus I'm not sure
what made the two events split, even they look exactly the
same otherwise. Maybe they are detached instances and the server, or
some other client, created them. I do not know, I'm only guessing here.
        Bye,
        Milan

[1] https://gitlab.gnome.org/GNOME/evolution/issues/385