Re: [PATCH v1 3/3] git: catch an attempt to run "git-foo"

From: Junio C Hamano <gitster@pobox.com>
Date: Aug 26, 2020, 01:19 UTC
Message-ID: <xmqqimd6xkyt.fsf@gitster.c.googlers.com>
In-Reply-To: <20200826011718.3186597-4-gitster@pobox.com>

Junio C Hamano <gitster@pobox.com> writes:

Show 17 quoted lines

> If we were to propose removing "git-foo" binaries from the
> filesystem for built-in commands, we should first see if there are
> users who will be affected by such a move.  When cmd_main() detects
> we were called not as "git", but as "git-foo", give an error message
> to ask the user to let us know and stop our removal plan, unless we
> are running a selected few programs that MUST be callable in the
> dashed form (e.g. "git-upload-pack").
>
> Those who are always using "git foo" form will not be affected, but
> those who trusted the promise we made to them 12 years ago that by
> prepending the output of $(git --exec-path) to the list of
> directories on their $PATH, they can safely keep writing
> "git-cat-file" will be negatively affected as all their scripts
> assuming the promise will be kept are now broken.
>
> Signed-off-by: Junio C Hamano <gitster@pobox.com>
> ---

The same idea as the one for pack-redundant. I do not use the technique to inspect $PATH and see if $GIT_EXEC_PATH is on it, as that would mean we will *not* bug users with legitimate need to keep the feature working, hence will not get "don't do that" objections.

We may want to ensure command_list[] is sorted by name and run binary search on it if running find_cmdname_help() for each and every dashed "git-foo" invocations turns out to be costly. Our conjecture behind this patch is that the form is rarely if ever used, so it may not matter at all, though.