bug#59662: 29.0.50; [PATCH] Add treesit--indent-defun

[Yuan Fu <casouri@gmail.com>]

Eli Zaretskii <eliz@gnu.org> writes:

> Resending with correct address of Yuan.
>
>> From: Theodor Thornhill <theo@thornhill.no>
>> Cc: 59662@debbugs.gnu.org, casouri@gmail.org
>> Date: Tue, 29 Nov 2022 13:14:21 +0100
>> 
>> Eli Zaretskii <eliz@gnu.org> writes:
>> 
>> >> Cc: eliz@gnu.org, casouri@gmail.org
>> >> From: Theodor Thornhill <theo@thornhill.no>
>> >> Date: Mon, 28 Nov 2022 20:32:01 +0100
>> >> 
>> >> I've added a function to treesit.el, for use in
>> >> treesit-major-mode-setup.  Because the treesit-defun-type-regexp gives
>> >> us "defuns" for free, we can set fill-paragraph-function to this new
>> >> function, thus enabling quick formatting, and some sensible default for
>> >> fill-paragraph.  It aims to mirror c-indent-defun.
>> >> 
>> >> I think this is a nice way to get this functionality for free, but I'm
>> >> not 100% whether this is considered ok or not.
>> >
>> > Sounds good, but why did you think it wouldn't be OK?  Anything here that
>> > doesn't meet the eye?
>> >
>> 
>> Not really, but see below answer.
>> 
>> >> An alternative could be to add a 'treesit-mode-map' where we can
>> >> auto-enable such constructs.
>> >
>> > I think this is less desirable.
>> >
>> > Yuan, WDYT?
>> >
>> >> @@ -1698,7 +1713,10 @@ treesit-major-mode-setup
>> >>    ;; Navigation.
>> >>    (when treesit-defun-type-regexp
>> >>      (setq-local beginning-of-defun-function #'treesit-beginning-of-defun)
>> >> -    (setq-local end-of-defun-function #'treesit-end-of-defun)))
>> >> +    (setq-local end-of-defun-function #'treesit-end-of-defun))
>> >> +  ;; Filling
>> >> +  (when (and treesit-defun-type-regexp treesit-simple-indent-rules)
>> >> +    (setq-local fill-paragraph-function #'treesit--indent-defun)))
>> >
>> > I'm a bit confused: if the function's name is treesit--indent-defun, and it
>> > uses treesit-indent-region to do its job, why do we assign it to
>> > fill-paragraph-function, which is supposed to _fill_, not to _indent_?
>> 
>> This is why I was thinking it would maybe be better to put it into a
>> treesit-mode-map that major-modes can inherit from, thus binding it to
>> things such as C-c C-q.  The reason I put it in filling was because that
>> is a common key to press in everything _but_ prog-modes.  And prog-modes
>> seem to mostly just turn it off if not inside of comments etc.  This
>> would behave just like that, except we would reformat/reindent/refill
>> code.
>> 
>> In a way filling _is_ formatting/reindenting, at least that's how I look
>> at it.
>> 
>> Theo
>> 

I was caught up in some stuff the past two days, sorry about that :-)
I’ll have a look tomorrow!

Yuan