Re: [PATCH] gc: introduce an --auto-exit-code option for undoing 3029970275

[Jonathan Nieder <jrnieder@gmail.com>]

Ævar Arnfjörð Bjarmason wrote:

>     Right. I know. What I mean is now I can (and do) use it to run 'git gc
>     --auto' across our server fleet and see whether I have any of #3, or
>     whether it's all #1 or #2. If there's nothing to do in #1 that's fine,
>     and it just so happens that I'll run gc due to #2 that's also fine, but
>     I'd like to see if gc really is stuck.
>
>     This of course relies on them having other users / scripts doing normal
>     git commands which would trigger previous 'git gc --auto' runs.
>
> I.e. with your change that command:
>
>     git gc --auto
>
> Would change to something like:
>
>     git gc --auto && ! test -e .git/gc.log
>
> Which, as noted is a bit of a nasty breaker of the encapsulation

That helps.  What if we package up the "test -e .git/gc.log" bit
*without* having the side effect of running git gc --auto, so that you
can run

	if ! git gc --detached-exit-code
	then
		... handle the error ...
	fi
	git gc --auto; # perhaps also with --detach

?

I'm not great at naming options, so the --detached-exit-code name is
bikesheddable.  What I really mean to ask about is: what if the status
reporting goes in a separate command from running gc --auto?

Perhaps this reporting could also print the message from a previous
run, so you could write:

	git gc --detached-status || exit
	git gc --auto; # perhaps also passing --detach

(Names still open for bikeshedding.)

Thanks and hope that helps,
Jonathan