bug#67262: python-ts-mode cannot identify triple-quoted-strings

[Dmitry Gutov]

On 12/12/2023 10:32, Yuan Fu wrote:

> > syntax-ppss-flush-cache is called by edits (and by the re-parse). It 
> > seems like it will be odd to have execution the other way around 
> > and/or add some hook into it which would call the re-parse and extend 
> > the region to be invalidated.
> >
> > syntax-propertize could have another hook added, yes. Or an advice.
> >
> > But it seems better to reuse some of the existing hooks, such as 
> > syntax-propertize-extend-region-functions. It treesit.c provided a way 
> > to fetch the newly-invalidated region, the treesit-major-mode-setup 
> > could add a new function to syntax-propertize-extend-region-functions 
> > which would invoke that feature. But even now it can instantiate the 
> > parse, which would call treesit-force-reparse internally, and then 
> > collect the info from the callbacks.
> syntax-propertize-extend-region-functions looks perfect. We just need to 
> force a reparse in it and the notifier will do the rest.
> > And yet another way - is to extend the region to be propertized from 
> > inside the major mode's syntax-propertize-function, invalidating some 
> > earlier entries too. The main problem with that, I think, is that 
> > every ts mode will have to repeat that trick. And that authors would 
> > have to know to do that. How to make that easier and more obvious, is 
> > a question.
> >
> > Finally, if I'm right that bug#66732 has a similar cause, then a 
> > shared solution that can be reused by syntax and font-lock (or 
> > preferably just fix both in the same place) would be ideal.
> >
> > > I'm not quite sure about how do we cause this re-parse. The 
> > > straightforward approach would be calling treesit-force-reparse[1] in 
> > > syntax-propertize/syntax-ppss-flush-cache. But ideally I'd like to 
> > > keep tree-sitter transparent for syntax.el. Maybe we can add a hook 
> > > in syntax-propertize/syntax-ppss-flush-cache.
> > >
> > > [1] This function doesn't exist yet, but it's easy to define in lisp.
> >
> > treesit-parser-root-node calls it anyway and does little else, so we 
> > could get by with just using it.
> Yep.

For the casual observer: I posted a solution using the above method in 
comments to bug#66732 yesterday.