Re: [PATCH v2] config: reject invalid VAR in 'git -c VAR=VAL command'

From: Jeff King <peff@peff.net>
Date: Feb 24, 2017, 04:22 UTC
Message-ID: <20170224042227.2rjgf4zbiadxbrtz@sigill.intra.peff.net>
In-Reply-To: <xmqqh93k5ijb.fsf@gitster.mtv.corp.google.com>

On Thu, Feb 23, 2017 at 08:17:44PM -0800, Junio C Hamano wrote:

Show 22 quoted lines

> > Hmm. I suspect one cannot do:
> >
> >   git -c 'section.subsection with an = in it.key=foo' ...
> >
> > Definitely not a new problem, nor something that should block your
> > patch. But if we want to fix it, I suspect the problem will ultimately
> > involve parsing left-to-right to get the key first, then confirming it
> > has an =, and then the value.
> 
> Backtracking will not fundamentally "fix" parsing of
> 
> 	a.b=c=.d
> 
> between twhse two
> 
> 	[a "b="] c = ".d"
> 	[a]      b = "c=.d"
> 
> unfortunately, I think.  I do not think it is worth doing the "best
> effort" with erroring out when ambiguous, because there is no way
> for the end user to disambiguate, unless we introduce a different
> syntax, at which point we cannot use config_parse_key() anymore.

Ah, yeah, you're right. I thought the problem was just that the "split" was too naive, but it really is that the whole syntax is badly specified.

I guess "git config --list" suffers from the same problem. You can get around it there with "-z", but that probably would not be very pleasant here. :)

Probably not worth worrying too much about if nobody is complaining.

-Peff