bug#73376: Treesitter does not rescan after indentation

[Yuan Fu <casouri@gmail.com>]

> On Sep 20, 2024, at 12:00 AM, pranshu sharma <pranshusharma366@gmail.com> wrote:
> 
> 
> After indenting, treesitter does not rescan the region.  This causes
> errors in the concrete syntax tree, which mess up indentation and syntax
> colouring.
> 
> The issue I'm having is kind of hard to explain, but in a summary I have
> the poorly indented code, where what's between '_'(which is not in the
> code itself) is coloured:
> ---------------
> f x =
>               let _a_ = 2
>                   _c_ = 1
>  in a
> --------------
> Then when I indent it with haskell-ts-mode, I get:
> ---------------
> f x =
>  let _a_ = 2
>      c = 1
>  in a
> --------------
> When the 2 snippets of code have the exact same meaning.  If I revert
> the buffer then the 'c' becomes coloured again.
> 
> This is not just problem with syntax highlighting, but if I was to
> indent the 2nd snippet it would mess it up, as it has the wrong CST.
> 

Hi Pranshu,

Thanks for the report. I can reproduce it. Let me see what’s going on here.

Yuan