Re: [PATCH] object-name: fix resolution of object names containing curly braces

From: Elijah Newren <newren@gmail.com>
Date: Jan 3, 2025, 23:34 UTC
Message-ID: <CABPp-BG47KNt5v3vEzPCCb+qRyz9473qPTfoOcTytb_Eis96SQ@mail.gmail.com>
In-Reply-To: <xmqqpll6wjsk.fsf@gitster.g>

On Wed, Jan 1, 2025 at 9:01 AM Junio C Hamano <gitster@pobox.com> wrote:

Show 25 quoted lines

>
> "Elijah Newren via GitGitGadget" <gitgitgadget@gmail.com> writes:
>
> > From: Elijah Newren <newren@gmail.com>
> >
> > Given a branch name of 'foo{bar', commands like
> >
> >     git cat-file -p foo{bar:README.md
> >
> > should succeed (assuming that branch had a README.md file, of course).
> > However, the change in cce91a2caef9 (Change 'master@noon' syntax to
> > 'master@{noon}'., 2006-05-19) presumed that curly braces would always
> > come after an '@' and be paired, causing 'foo{bar:README.md' to
> > entirely miss the ':' and assume there's no object being referenced.
> > In short, git would report:
> >
> >     fatal: Not a valid object name foo{bar:README.md
> >
> > Change the parsing to only make the assumption of paired curly braces
> > immediately after a '@' character appears.
>
> Interesting.  I wonder if this looseness was to ensure that we won't
> mistake a colon inside "master^{/title with : a colon}" as a start
> of a subpath, instead of asking for a commit with a title that
> happens to have a colon in it?

Yeah, good catch, my changes would for example break parsing
  master^{/object-name:}:t/t1006-cat-file.sh

I'll fix that and add a testcase.