bug#38165: 12.2.0; Syntax highlighting broken when there are too many characters in equation/align environment

[Ruiyang Wu]

Hi Arash,

Thanks for your reply. You are right, I just figured out this is not a bug of auctex, but a bug of polymode instead. L224 in `polymode-compat.el' messes up with font lock, and causes this problem in LaTeX mode.

Although this is not quite relevant to auctex, a temporary workaround would be: 

(with-eval-after-load "polymode-compat"
  (advice-remove 'font-lock-extend-region-multiline 'pm-check-for-real-change-in-extend-multiline))

Best,

Ruiyang

On Tue, Nov 12, 2019 at 1:11 PM Arash Esbati <address@hidden> wrote:

Hi Ruiyang,

Ruiyang Wu <address@hidden> writes:

> The problem can be reproduced with the `test.tex' file attached below. When
> I tried to add more characters to the `align' environment in `test.tex',
> the syntax highlighting becomes extremely unstable, switching between math
> and plain text highlighting.

I can't reproduce what you describe.  Your file looks like this for me
where adding additional characters is no problem:


> Emacs  : GNU Emacs 26.3 (build 1, x86_64-w64-mingw32)
>  of 2019-08-29

I'm using Emacs 27 pretest.  Maybe you can try it as well and see if the
issue persists.  You can fetch it from here:

    https://alpha.gnu.org/gnu/emacs/pretest/windows/emacs-27/

Best, Arash

--

Ruiyang Wu

Graduate Student

Department of Mathematics

University of Arizona

Tucson, AZ, 85721    USA