We set GIT_OPTIONAL_LOCKS=0 for every git command we run. That env var
only affects `git status`: it tells git not to take the optional lock it
would otherwise use to write the index back after refreshing the cached
stat information. The intent was to avoid contending for index.lock with
git commands the user runs in a terminal.
The downside is that our `git status` never persists the refreshed
stat-cache. So whenever the working tree's cached stat info goes stale
(e.g. editing files and discarding the changes, or a checkout), every
subsequent status re-hashes the affected files to confirm they're clean,
and stays slow until something else writes the index (such as the user
running `git status` in a terminal).
Fix this by only suppressing optional locks for refreshes that run
unattended in the background; foreground refreshes triggered by a user
action now run a plain `git status` that writes the refreshed index back,
just like the command line does. Background refreshes keep passing
--no-optional-locks so they still can't cause lock contention.
RefreshOptions gains a Background flag that the background routines set,
threaded down to the status command.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Also, use the user's shell (from the SHELL env variable) instead of bash. Both
of these together allow users to use their shell aliases or shell functions in
the interactive command prompt.
By constructing an arg vector manually, we no longer need to quote arguments
Mandate that args must be passed when building a command
Now you need to provide an args array when building a command.
There are a handful of places where we need to deal with a string,
such as with user-defined custom commands, and for those we now require
that at the callsite they use str.ToArgv to do that. I don't want
to provide a method out of the box for it because I want to discourage its
use.
For some reason we were invoking a command through a shell when amending a
commit, and I don't believe we needed to do that as there was nothing user-
supplied about the command. So I've switched to using a regular command out-
side the shell there
