Re: bug:git-check-ignore exit status is wrong for negative patterns when -v option used

From: Junio C Hamano <gitster@pobox.com>
To: Jeremy Faith <jeremy.faith@jci.com>
Cc: "git@vger.kernel.org" <git@vger.kernel.org>
Subject: Re: bug:git-check-ignore exit status is wrong for negative patterns when -v option used
Date: Wed, 28 Apr 2021 16:13:14 +0900	[thread overview]
Message-ID: <xmqqfszac25x.fsf@gitster.g> (raw)
In-Reply-To: <CY4P132MB00885C970ACF5A277F06E40385419@CY4P132MB0088.NAMP132.PROD.OUTLOOK.COM> (Jeremy Faith's message of "Tue, 27 Apr 2021 16:30:13 +0000")

Jeremy Faith <jeremy.faith@jci.com> writes:

> git version 2.31.1.362.g311531c9de
> git-check-ignore 
> When a negative pattern is the last .gitignore match the -v option causes the exit status to be 0 rather than the expected 1.
> e.g say .gitignore contains  one line: !hello
> git check-ignore hello #outputs nothing
> echo $?  #shows correct exit status=1 i.e None of the provided paths are ignored.
> but
> git check-ignore -v hello #output is next line
> .gitignore:4:!hello	hello
> echo $?  #shows wrong exit status=0 i.e. One or more of the provided paths is ignored

Hmph.  This is kind of understandable given the history of the
command, which was *not* about programatically ask "is this path
ignored?" question at all.  Instead, it was invented to answer this
question: I am puzzled by the fact that Git considers this path is
to be ignored (or "not to be ignored").  Show me which entry in what
exclude file made the final decision to ignore (or "not to ignore")
it to help me debug my ignore file(s).

And the exit code was to signal "yes, I found a relevant entry",
which made sense for the tool's nature as a debugging aid.

So, I suspect that this is working as designed/intended.  I agree
that it is debatable that the way it was designed to work is a good
one, though.