On Thu, Oct 12, 2023 at 10:28:16AM -0700, Junio C Hamano wrote:

Erik Cervin Edin [off-list ref] writes:

quoted

In the Git repository, I ran

    echo tig > pattern-file &&
        echo git > xdiff/pattern-file &&
        cd xdfiff &&
        git grep -f pattern-file

What did you expect to happen? (Expected behavior)

Git grep -f to read the pattern-file, in the xdiff directory and
search for lines matching `git` in the xdiff directory.

That does sound like a bug.  It should use the original directory as
the base of the relative path computation, similar to the way how
OPT_FILENAME() options are handled.

Perhaps something along this line, but this is not even compile
tested yet.

Just going through old mail that I didn't have a chance to respond to,
the proposed patch that you included here does compile and pass t7810
for me, and the fix looks reasonable as-is. I don't think I see this
patch on master, but would have no objections to you merging it down.

Thanks,
Taylor