bug#72570: 31.0.50; Regression in date-to-time

[Paul Eggert <eggert@cs.ucla.edu>]

On 2024-08-12 22:55, Ulrich Mueller wrote:

> don't we have a chicken-and-egg problem? We'd need the UTC timestamp
> to infer the timezone, but the timezone to calculate the timestamp?

You're quite right that we have a chicken and egg problem, and that no 
solution will be perfect here. My point was that using a heuristic would 
be better than nothing, if the goal is to infer timezone from incomplete 
input. That's why timezone-fix-time uses this heuristic.

I continue to think that your idea of changing date-to-time to default 
to the local time zone is the best way to move forward. How about this 
idea for doing it?

* Change the doc to say this. This is a simple change, and it reflects 
existing behavior better.

* Change date-to-time so that if it falls back on 
timezone-make-date-arpa standard, it insists that the string denotes a 
time zone; if the string lacks a time zone it errors out with "Invalid 
date", which it already does with invalid dates.