bug#67117: [PATCH] Tree-sitter: fix an issue when searching subtree backward

[Eli Zaretskii]

> From: Denis Zubarev <dvzubarev@yandex.ru>
> Date: Sun, 12 Nov 2023 02:38:33 +0300
> 
> Steps to reproduce the issue:
> 1. emacs -Q
> 2. M-x find-file /tmp/t.py
> 3. paste to the buffer
>  
> Temp(1, 2) 
>  
> 4. M-x python-ts-mode
> 5. Call search-subtree with backward flag
>    M-x eval-expression (treesit-search-subtree
>                (treesit--thing-at (point) "call")
>                (lambda (n) (equal (treesit-node-type n ) "integer"))
>                t)
> It should return the second int node (#<treesit-node integer in 9-10>), but 
> it returns nil.

Yuan, any comments to the patch and the issue in general?

Denis, your changes are too large for us to accept them without a
copyright assignment.  Would you like to start your assignment
paperwork at this time, so that we could accept this contribution, and
all your future ones?

Thanks.