Re: [PATCH] various: disallow --no-no-OPT for --no-opt options

[Jeff King <peff@peff.net>]

On Wed, Apr 19, 2017 at 09:02:52AM +0200, Ævar Arnfjörð Bjarmason wrote:

> On Wed, Apr 19, 2017 at 4:50 AM, Jeff King <peff@peff.net> wrote:
> > On Tue, Apr 18, 2017 at 07:40:37PM -0700, Junio C Hamano wrote:
> >
> >> > It might even be possible to detect the existing line and
> >> > have parse-options automatically respect "--foo" when "--no-foo" is
> >> > present.  But that may run afoul of callers that add both "--foo" and
> >> > "--no-foo" manually.
> >>
> >> True but wouldn't that something we would want to avoid anyway?
> >> That is, "git cmd [--OPT | --no-OPT | --no-no-OPT]" from the end
> >> user's point of view should be an error because it is unclear what
> >> difference there are between --OPT and --no-no-OPT.  And we should
> >> be able to add a rule to parse_options_check() to catch such an
> >> error.
> >
> > I meant that if you have something like this in your options array:
> >
> >   { 0, "foo", OPTION_INTEGER, &foo, 1 },
> >   { 0, "no-foo", OPTION_INTEGER, &foo, 2 },
> 
> I may be missing something, but don't we already do exactly what
> you're describing here? See commit f1930c587 ("parse-options: allow
> positivation of options starting, with no-", 2012-02-25) from René
> Scharfe.

Oh, so we do. I somehow totally missed that.

I think all is well, then. We do accept --no-no-foo still. IMHO it is
not that big a deal (as long as we do not advertise it, then it does not
hurt unless somebody actually tries it). But I do not mind if it goes
away, as long as the positive --foo form still works (and it sounds from
Jake's response that we'd need to do more than just NONEG there).

-Peff