Re: Diary icalendar tests still broken

Richard Lawrence [31/Jul  8:19am +02] wrote:
> The patch looks big, because it tweaks the representation of one of the
> most widely-used data structures, but in fact it is a small change and I
> am pleased with how easy it was to make.  I can't promise there are no
> new bugs, but I *am* confident that this patch is strictly an
> improvement over the code without it, and any new issues will be minor.
>
> --
> Best,
> Richard
>
> From 812d91be7118c1deb258466da7c6b5ace8053e93 Mon Sep 17 00:00:00 2001
> From: Richard Lawrence <[email protected]>
> Date: Wed, 29 Jul 2026 09:29:25 +0200
> Subject: [PATCH] Distinguish UTC vs. UTC+0:00 times in iCalendar library
>
> This fixes a bug discussed on emacs-devel; see the thread at
> https://https://lists.gnu.org/archive/html/emacs-devel/2026-07/msg00445.html
>
> The issue was that the library did not distinguish between UTC time and
> times that have an offset of 0 but are not in the UTC time zone,
> e.g. standard times in Europe/London or Europe/Dublin.  This led to test
> failures on systems in these time zones.  This fix represents true UTC
> times by inserting the special value `t' in the zone slot of a decoded
> time at parse time (which `encode-time' already handles correctly).
> This distinguishes them from decoded times with an offset of 0 seconds.

Stefan, do I recall correctly that you originally reviewed this new
library?  Would you be able to review this patch?

Eli, what do you think about installing this on the release branch?
I'm wondering whether we should just disable the tests instead.
On the other hand, the library is new in Emacs 31 and is fairly niche,
so maybe we should go with the idea that this is a pareto improvement,
as Richard argues.

-- 
Sean Whitton