`jj` sets `LC_ALL` when invoking `git`, which can trickle down to GUI subprocesses

[michaelpj]

Description

jj sets LC_ALL=C when starting git subprocesses. However, this can trickle down through ssh to ssh-askpass programs, some of which can be GUI programs that don't like LC_ALL=C. For example, I get this when using ksshaskpass:

git: Detected locale "C" with character encoding "ANSI_X3.4-1968", which is not UTF-8.
git: Qt depends on a UTF-8 locale, and has switched to "C.UTF-8" instead.
git: If this causes problems, reconfigure your locale. See the locale(1) manual
git: for more information.

Steps to Reproduce the Problem

1. Configure git to use a QT-based askpass like ksshaskpass
2. Perform a jj operation that requires auth, like pushing a branch

Expected Behavior

GUI subprocesses of git see the user's configured locale.

Actual Behavior

GUI subprocesses of git see LC_ALL=C

Specifications

• Platform: NixOS
• Version: 0.39

[michaelpj]

I guess perhaps jj could set LC_ALL=C.UTF-8 instead, and that would be a bit more likely to avoid problems. But presumably this could present a real issue if e.g. a user has a non-English language configured and they actually need to interact with the askpass subprocess.