bug#64647: treesit-query-error due to a recent change to tree-sitter-javascript grammar definition

[Eli Zaretskii]

> From: Theodor Thornhill <theo@thornhill.no>
> Cc: Vincenzo Pupillo <v.pupillo@gmail.com>,  Jostein Kjonigsen
>  <jostein@kjonigsen.net>,  64647@debbugs.gnu.org
> Date: Sat, 15 Jul 2023 19:54:03 +0200
> 
> Eli Zaretskii <eliz@gnu.org> writes:
> 
> >> The patch in attachment fixes both problems.
> >
> > Will the patch work with the grammar libraries before the recent
> > change?
> >
> 
> It will introduce regressions, but the patch itself is a change for the
> better, both in emacs land and in the grammar itself. 

What kinds of regressions?

> I don't disagree, but I think this is a difficult problem to solve, but
> with an easy cop-out solution that most other implementors use - just
> refer to the last supported commit. We've had some discussions on this,
> but IIRC we never settled on anything. Personally, I think a
> 
> ;;; Tree-sitter-version: bb1f97b643b77fc1f082d621bf533b4b14cf0c30
> 
> header may be the simplest way to at least signal some awareness
> here. That way the auto install mechanism can pull that hash directly
> and we can ensure some sort of compatibility checking.
> 
> What do you think?

I think what I wrote: that we should try to make our modes work with
reasonably old versions of the grammars, if that is practical.  While
in general it could be a very difficult, if not impossible, to achieve
that, the question is whether this particular issue can be solved in
that manner.  If it can, we should do it.