bug#58979: closed (treesitter-regression with json-mode)

[GNU bug Tracking System]

Your message dated Sat, 7 Jan 2023 15:10:14 -0800
with message-id <F3B916BB-4966-4C1E-B3C6-1421814587F7@gmail.com>
and subject line Re: bug#58979: treesitter-regression with json-mode
has caused the debbugs.gnu.org bug report #58979,
regarding treesitter-regression with json-mode
to be marked as done.

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58979: https://debbugs.gnu.org/cgi/bugreport.cgi?bug=58979
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--- Begin Message --- Subject: treesitter-regression with json-mode Date: Wed, 2 Nov 2022 17:16:08 +0100

When I open a large json file (about 3_000_000 lines, about 72Mb, pretty-printed) Emacs 29.0.50 opens the file just fine in `js-json-mode` and when using regexp-based font locking, it works well.

When I force this buffer into _javascript_-mode, Emacs hangs. Memory consumption as reported by Windows task manager "dances" around 2Gb, yet even after waiting for three minutes, Emacs doesn't get responsive any more.

I consider this an unfortunately regression as recent commits to Emacs 29 (long lines patches) actually makes working with such large files with long lines absolutely pleasant, yet as it seems the interaction with tree-sitter destroys this gains.

--- End Message ---

> --- Begin Message ---
>
>
>
> Subject: 
>
> Re: bug#58979: treesitter-regression with json-mode
>
>
>
>
> Date: 
>
> Sat, 7 Jan 2023 15:10:14 -0800
>
>
>
>
> Yuan Fu <casouri@gmail.com> writes:
>
> > Stefan Kangas <stefankangas@gmail.com> writes:
> >
> >> Johann Höchtl <johann.hoechtl@gmail.com> writes:
> >>
> >>> When I open a large json file (about 3_000_000 lines, about 72Mb,
> >>> pretty-printed) Emacs 29.0.50 opens the file just fine in
> >>> `js-json-mode` and when using regexp-based font locking, it works
> >>> well.
> >>>
> >>> When I force this buffer into javascript-mode, Emacs hangs. Memory
> >>> consumption as reported by Windows task manager "dances" around 2Gb,
> >>> yet even after waiting for three minutes, Emacs doesn't get responsive
> >>> any more.
> >>>
> >>> I consider this an unfortunately regression as recent commits to Emacs
> >>> 29 (long lines patches) actually makes working with such large files
> >>> with long lines absolutely pleasant, yet as it seems the interaction
> >>> with tree-sitter destroys this gains.
> >>
> >> Copying in Yuan Fu.
> >
> > Again, sorry for the delay, I just saw this report :-)
> >
> > Since your previous report is actually about emacs-tree-sitter, I think
> > this one is too?
> >
> > Anyway, since tree-sitter is merged into master now, if you rebuild
> > master and turn on json-ts-mode, you should be in tree-sitter backed
> > JSON mode. I’d give that a try and see if works fine.
> >
> > Thanks,
> > Yuan
>
> Closing this report since I think there’s nothing to do. Feel free to
> reopen.
>
> Yuan
>
>
> --- End Message ---