bug#59415: 29.0.50; [feature/tree-sitter] c-ts-mode fails to fontify a portion of a large C file

[Eli Zaretskii]

> From: Yuan Fu <casouri@gmail.com>
> Date: Sun, 20 Nov 2022 17:27:16 -0800
> Cc: Eli Zaretskii <eliz@gnu.org>,
>  59415@debbugs.gnu.org
> 
> I pushed a change that uses treesit-node-on. Now scrolling in most parts of 
> the buffer is pretty fast. Scrolling around 194770 is still laggy, because 
> the node we get from treesit-node-on is still too large. I tried some 
> heuristics but they didn’t work very well, IMO because tree-sitter couldn’t 
> parse that part of the code very well. The code should observe a structure 
> like {{}, {}, {}, {}, {}, …} where there are tens thousands of inner 
> brackets, so ideally we only need to grab the {}’s in the region we want to 
> fontify. But tree-sitter seems to understand it in some weird structure and 
> we still end up with very large nodes, which is far larger than the region we 
> want to fontify and is slow to query.
> 
> I’ll try to improve it further in the future, but for now I think it’s good 
> enough (because in most cases fontification is pretty fast).

Agreed.

Thanks, I think we can close the bug now.

What do you think about enlarging treesit-max-buffer-size as I proposed
up-thread?