Subject: bug#37655: 27.0.50; reversing `gnus-thread-sort-by-most-recent-date' does not work properly

From: Eric Abrahamsen <[email-masked]>
Date: Wed, 09 Oct 2019 14:32:12 -0700

On 10/09/19 14:08 PM, Hong Xu wrote:
> On 10/9/19 2:04 PM, Eric Abrahamsen wrote:
>> Hong Xu <[email-masked]> writes:
>> 
>>> On 10/9/19 11:55 AM, Eric Abrahamsen wrote:
>>>> I can reproduce this, but oddly it only seems to have gone wrong for
>>>> that one thread -- all the other threads in the mailbox seem to be
>>>> sorted correctly. I also note that the Summary buffer displays the date
>>>> of both messages in the thread as one day earlier than the Date header
>>>> in the message itself. So I wonder if there's just something weird about
>>>> one or both of the messages that's causing Gnus to handle the date
>>>> incorrectly.
>>>> When I have a bit more time I'll try to figure out what date Gnus is
>>>> trying to use for that thread.
>>>>
>>>
>>> On my personal messages, there is also only exactly one thread placed
>>> in the wrong position. My guess is that there may be something on the
>>> boundary not handled properly during sorting ...
>> Ah, I guess that would make sense. Are the dates also displayed
>> incorrectly in the Summary format line for the messages in that thread?
>> 
>
> I don't observe incorrect date. Is there an incorrect date in the example above?

Yes, the dates as displayed in the Summary format line are off from the
dates in the Date header of the article itself. At least, that's what
I'm seeing in the Emacs -Q test.

In your personal messages, is it also the first thread in the Summary
buffer that's sorted incorrectly? That would definitely indicate some
sort of error in the start/end of looping.

> I also observed that `gnus-thread-latest-date' does not return correct
> dates for some messages, although they displayed as in one thread.

Okay, noted. I'll probably have time to look deeper tomorrow.