bug#62333: 30.0.50; Issue with tree-sitter syntax tree during certain changes

[Dmitry Gutov]

On 25/03/2023 18:24, Eli Zaretskii wrote:
> > From: Dmitry Gutov <dgutov@yandex.ru>
> > Cc: "wkirschbaum@gmail.com" <wkirschbaum@gmail.com>,
> >         "casouri@gmail.com" <casouri@gmail.com>,
> >         "62333@debbugs.gnu.org" <62333@debbugs.gnu.org>
> > Date: Sat, 25 Mar 2023 19:03:45 +0300
> >
> >    But if the mmm framework narrowed the region to the current mode's
> >    block, widening will force tree-sitter to parse the whole buffer.
> >
> >   No, because such a mode mode should already make sure this doesn't
> >   happen.
> >
> > How?
>
> The same way it makes sure a given parser is used only on the portion
> of the buffer where the corresponding language is used.

It uses narrowing. Major modes are not supposed to 'widen' willy-nilly.