Re: [PATCH v2 4/4] allow recovery from command name typos

[Tay Ray Chuan <rctay89@gmail.com>]

On Thu, Jul 26, 2012 at 1:57 AM, Junio C Hamano <gitster@pobox.com> wrote:
>
> Tay Ray Chuan <rctay89@gmail.com> writes:
>
> > If suggestions are available (based on Levenshtein distance) and if the
> > terminal isatty(), present a prompt to the user to select one of the
> > computed suggestions.
>
> The way to determine "If the terminal is a tty" used in this patch
> looks overly dangerous, given that we do not know what kind of "git"
> command we may be invoking at this point.

Indeed, it should also have considered stdin's tty-ness.

> Perhaps we should audit "isatty()" calls and replace them with a
> helper function that does this kind of thing consistently in a more
> robust way (my recent favorite is Linus's somewhat anal logic used
> in builtin/merge.c::default_edit_option()).

Any specific callers to isatty() you have in mind? A quick grep shows
that a significant portion of the "offenders" are isatty(2) calls to
determine whether to display progress, I think those are ok.

The credential helper has some prompting functionality that is close
to what I intend to do here, but I think it can make some assumptions
about stdin/stdout that we can't, as you have pointed out. So that
leaves merge-edit and this patch as the beneficiaries of a
builtin/merge.c::default_edit_option() refactor. That's just off the
top of my head.

Perhaps the helper function could be named "git_can_prompt()" and
placed in prompt.c?

--
Cheers,
Ray Chuan