bug#34315: [PATCH] icalendar.el: DURATION fix + more robust timezone handling

[Ulf Jasper]

Am 01.10.2020 um 20:47 (+0200) schrieb Lars Ingebrigtsen:

> But surely not all the tests are transforms in this way.  Reading an ics
> file and having a test that says "what's the meeting time in this file?"
> should be a fine test, right?

Basically icalendar.el just does transformations from ics to Emacs diary
and vice versa.  Correspondingly icalendar-tests consist of import and
export tests plus tests of lower-level functions.  The file based
approach would apply to the im-/export tests only.