Re: Why does git-grep appear to treat exclude pathspecs differently?

>
> On Wed, Jul 30, 2025 at 05:49:29PM -0400, D. Ben Knoble wrote:
>
> > which eventually dies as noted. However:
> >
> > - looks_like_pathspec() only checks for long magic, as you noted
> > - setup.c:check_filename() looks for short-magic, too, but only
> > considers ":^" to work like a pathname if we're excluding everything?
> >
> > I think what I find confusing is that, while this is definitely a DWIM
> > case for git-grep, it doesn't seem to do DWIM :) We are verifying that
> > the remaining arguments are filenames, but couldn't they really be
> > full pathspecs, as long as they aren't revisions?
> >
> > The difference for "^:<path>" from ":^:<path>", just to complete the
> > story, is that in setup.c:check_filename() we try to stat whatever
> > comes after ":^":
> > - for the former, that's <path> and we are ok
> > - for the latter, that's :<path>, fail.
> >
> > So it seems like the places that check for short-magic should also
> > consider the optional trailing colon?
>
> Yeah, I'd think so. But it's worse than that, even. According to the
> glossary definition you showed:
>
>   In the short form, the leading colon `:` is followed by zero or more
>   "magic signature" letters (which optionally is terminated by another
>   colon `:`)
>
> we allow multiple bits of magic. So the code in check_filename() that
> looks for ":/", ":^", etc would be fooled when seeing more than one
> character, like: ":/^exclude-from-root". AFAICT there are only two short
> magic types, so I guess nobody has really run into this before.

>
> Also, I guess this function ought to be respecting the literal_pathspecs
> global? The actual pathspec parser does.
>
> If we can, we probably ought to be feeding the paths to a function like
> pathspec.c:parse_element_magic() and then checking the resulting flags
> (and skipping past the prefix as it indicates).

>
> -Peff
>
> PS I didn't even know that we allowed multiple short items or a trailing
>    colon until your email! Hidden corners of Git.