On Sat, Jul 26, 2025 at 8:28 PM Junio C Hamano <gitster@xxxxxxxxx> wrote:
>
> "D. Ben Knoble" <ben.knoble+github@xxxxxxxxx> writes:
>
> > When asking for short help on a previous command, the user may use their
> > shell history to recall a command like
> >
> > git rebase new-base
> >
> > Then inserting "-h" after "rebase" doesn't yield the help; make it so.
>
> I doubt this is a good idea for at least two reasons.
As I said in the cover letter, I think this is the most controversial
and can be dropped. However…
> * As "git help cli" says, we should be discouraging, not
> encouraging peope to say "git rebase new-base -h".
…that's not what I'm encouraging here. Instead, it's more like below:
> * "git rebase -h new-base" that shows help is probably a bug (think
> what should happen with s/rebase/grep/) in the first place.
And at least according to my tests, "git grep -h new-base" still greps
rather than shows help. Compare
- "git grep -h squash" (greps squash)
- "git rebase -h @{u}" (shows help)
> If anything, we probably should fix the "-h" codepath to
>
> - react and do the short-help only when "-h" is the only command
> line option; with argument, it should probably barf, saying "-h
> does not take an argument".
I think we have the first half already ("argc == 2" in the preimage).
I'm not interested in writing the second half right now, personally,
if we end up dropping this patch, so someone else could take that up.
> - if "-h" resulted in reported an alias, it should stop there.
> E.g. "git -c alias.x=ls-files x -h" would currently invoke "git
> ls-files -h" after reporting that 'x' is aliased to 'ls-files'.
> If the alias is to one of our commands, it is not too risky, but
> otherwise we should not assume it is safe to append "-h" to the
> underlying command and run it. Imagine
>
> $ git -c alias.x='!echo rm -rf .' x -h
>
> and worse yet, if your alias did not have "echo" in it ;-)???
>
> The only end-user expectation we can safely assume is when they
> say,
>
> $ git frotz -h
>
> is that they would get a help on 'frotz' without doing any harm.
> If frotz is an alias to some external command, for which we have no
> idea what it would do when we run it with "-h" appended to the
> command line, the user would be in a lot of pain if the aliased
> operation is destructive.
>
I think this is being discussed on another series, and I'll leave it there :)
