Eric Abrahamsen <eric@ericabrahamsen.net> writes:

> Katsumi Yamaoka <yamaoka@jpl.org> writes:
>
>>> On 04/23/19 17:12 PM, Katsumi Yamaoka wrote:
>>>> Though I'm not quite sure
>>>> yet, the new and the old newsrc.eld files (containing non-ASCII
>>>> nnml and nnrss groups) seem to be compatible with the new and
>>>> the old Gnus mutually.
>>
>> Not mutually but one-way from old Gnus[1] to new Gnus[2] is ok.
>> To activate the groups of the non-ASCII names for the old Gnus,
>> I realized I needed to convert those group names to that of
>>
>> (prin1-to-string (encode-coding-string "Group Name" 'utf-8))
>>
>> one by one in the .newsrc.eld file before starting the old Gnus.
>> No other tweak is necessary to switch back to the old Gnus, and
>> nothing to be done to switch to the new Gnus again.  I verified
>> it with only nnml and nnrss groups as I tried Gnus of the latest
>> git master today for the first time in about a month.
>>
>> [1] currently that of the master and the emacs-26 branches
>> [2] currentlt that of the scratch/gnus-decoded branch
>
> Thanks for the analysis. I think I only had nnimap groups that were
> properly (utf-8) encoded in .newsrc.eld, but still worked with the "old"
> Gnus code (in your sense, above). I guess that was different with
> nnml/nnrss.
>
> I have some more group sorting issues to fix in the current master code,
> then I'll call for testers for the scratch/gnus-decoded branch, then
> hopefully this whole thing can go in.

Before that, I realized that I hadn't updated some of the *Group* buffer
sorting code, for sorting flat groups. The attached patch should go into
master, and then master merged into scratch/gnus-decoded.

Eric