Re: bug?: git grep HEAD with exclude in pathspec not taken into account

From: Duy Nguyen <pclouds@gmail.com>
Date: Oct 24, 2018, 15:14 UTC
Message-ID: <CACsJy8C7pArdayQu9Kh5z6dczCqV_=XJP4wzR_dcm_W3MgG+Jg@mail.gmail.com>
In-Reply-To: <CAGOLd-5Gbt6fQTvm+7018uX+8WF7NUWpa1sFWAg3-5bxtmOt-Q@mail.gmail.com>

On Wed, Oct 24, 2018 at 4:55 PM Christophe Bliard <christophe.bliard@trux.info> wrote:

Show 30 quoted lines

>
> Hi,
>
> I observed an unexpected behavior while using git grep with both git
> 2.19.1 and 2.14.3. Here is how to reproduce it:
>
> > git init
> Initialized empty Git repository in /private/tmp/hello/.git/
> > echo foo > fileA
> > echo 'foo is false+' > fileB
> > git add fileA
> > git commit -m fileA
> [master (root-commit) f2c83e7] fileA
>  1 file changed, 1 insertion(+)
>  create mode 100644 fileA
> > git add fileB
> > git commit -m fileB
> [master e35df26] fileB
>  1 file changed, 1 insertion(+)
>  create mode 100644 fileB
> > git --no-pager grep foo HEAD -- ':!fileA'
> HEAD:fileB:foo is false+
> > git --no-pager grep foo HEAD -- ':!fileB'
> HEAD:fileA:foo
> HEAD:fileB:foo is false+
>
> In the last command, fileB appears in grep results but it should have
> been excluded.
>
> If the HEAD parameter is removed, it works as expected:

It's probably a bug. We have different code paths for matching things with or without HEAD, roughly speaking. I'll look into to this more on the weekend, unless somebody (is welcome to) beats me first.

Another thing that might also be a problem is, negative patterns are supposed to exclude stuff from "something" but you don't specify that "something" (i.e. positive patterns) in your grep commands above. If "grep foo HEAD -- :/ ':!fileB'" works, then you probably just run into some undefined corner case.

-- 
Duy