bug#18640: [wishlist] fontconfig's cache is not refreshed automatically

bug#18640: [wishlist] fontconfig's cache is not refreshed automatically

[Mark H Weaver]

When a user runs emacs (or any other program that uses fontconfig), a
cache is created in ~/.cache/fontconfig.  This cache is not updated
automatically after installing new fonts, and must be manually cleared
out.

I guess this might be related to our use of Jan 1, 1970 as the
timestamps for all files in /gnu/store (which includes user profiles).

We should either modify fontconfig to detect a stale cache using a
method that works on Guix, or else notify the user that they must clear
the cache after installing ttf fonts.

      Mark

bug#18640: fontconfig's cache is not refreshed automatically

[宋文武 via Bug reports for GNU Guix]

Hello, I believe this issue had been fixed by:

commit 6f12880a76a6c91058718d15845f8b9d9b529a5a
Author: Sarah Morgensen <iskarian@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).

Closing.