bug#26877: building fonts: fontcache must be updated regulary

["宋文武 via Bug reports for GNU Guix" <bug-guix@gnu.org>]

Maxim Cournoyer <maxim.cournoyer@gmail.com> writes:

> Hello,
>
> ludo@gnu.org (Ludovic Courtès) writes:
>
>> Hi,
>>
>> Mark H Weaver <mhw@netris.org> skribis:
>>
>>> The usual Guix way to handle things like this is to arrange for the font
>>> cache to be part of the profile, and to create a profile hook that
>>> creates the cache from all of the built packages included within.
>>
>> The problem is that the cache should be mutable so that one can run
>> “fc-cache -f” after having dropped files in ~/.local/share/fonts, for
>> instance.
>>
>> That said, quite surprisingly, I think I never had to run ‘fc-cache’
>> except in the situation above.
>
> I've never had to do this in years, although I don't use "loose" fonts
> manually installed under ~/.local/share/fonts.
>
> Should we close the issue?  Our fontconfig package now honors fonts
> found under XDG_DATA_DIRS, and it seems to just work.


Hello, I think we can close this now, since this commit:

commit 6f12880a76a6c91058718d15845f8b9d9b529a5a
Author: Sarah Morgensen <iskarian <at> mgsn.dev>
Date:   Fri Jun 18 17:52:05 2021 -0700

    gnu: fontconfig: Use (locally) deterministic caching
    
    Make fontconfig use directory contents rather than modification time to
    determine cache validity (by pretending that mtime is broken).

There is no need to run 'fc-cache' manually, and applications just need
close/restart to use newly install fonts (also manual run here doesn't
remove the need of restart).