bug#61356: 29.0.60; wrong-type-argument in treesit-indent-region when indenting a C buffer

[Eli Zaretskii]

> Date: Tue, 07 Feb 2023 23:20:09 +0100
> From:  Daniel Martín via "Bug reports for GNU Emacs,
>  the Swiss army knife of text editors" <bug-gnu-emacs@gnu.org>
> 
> 
> Steps to reproduce the problem:
> 
> emacs -Q
> C-x C-f emacs/src/xdisp.c RET
> M-x c-ts-mode RET
> C-x h
> TAB
> 
> Expected result:
> 
> The buffer is reindented.
> 
> Actual results:
> 
> The operation fails with this error:
> 
> Debugger entered--Lisp error: (wrong-type-argument integer-or-marker-p nil)
>   treesit-indent-region(1 1214226)
>   indent-region(1 1214226)
>   indent-for-tab-command(nil)
>   funcall-interactively(indent-for-tab-command nil)
>   call-interactively(indent-for-tab-command nil nil)
>   command-execute(indent-for-tab-command)

Thank you for your report.

Yuan and Theo, could you please look into this?  I briefly stepped
through the code involved in the problem, and it sounds like it makes
some assumptions regarding the nodes which are not necessarily true in
Real Life.