Re: Missing features in c-ts-mode

[Theodor Thornhill <theo@thornhill.no>]

Eli Zaretskii <eliz@gnu.org> writes:

>> From: Theodor Thornhill <theo@thornhill.no>
>> Cc: casouri@gmail.com, emacs-devel@gnu.org
>> Date: Wed, 15 Feb 2023 20:31:33 +0100
>> 
>> This patch adds some support for this- but I'm not really satisfied yet.
>> It will electrically indent if you've typed "#i", or if you insert "#"
>> before say, "if".  The reason it behaves this way right now is that the
>> parser returns an (ERROR (ERROR)) node when only # is inserted.  I'll
>> see if I can find some workaround for it.
>
> Thank you for working on this.


Ok so I found a way which will probably work well.  I just need to
figure out if there are any other cases where we get the (ERROR (ERROR))
pattern.  If not I'll add some tests and also this:

diff --git a/lisp/progmodes/c-ts-mode.el b/lisp/progmodes/c-ts-mode.el
index 020f2642ac2..a60c464093e 100644
--- a/lisp/progmodes/c-ts-mode.el
+++ b/lisp/progmodes/c-ts-mode.el
@@ -219,6 +219,7 @@ c-ts-mode--indent-styles
 MODE is either `c' or `cpp'."
   (let ((common
          `(((parent-is "translation_unit") point-min 0)
+           ((query "(ERROR (ERROR)) @indent") point-min 0)
            ((node-is ")") parent 1)
            ((node-is "]") parent-bol 0)
            ((node-is "else") parent-bol 0)
@@ -785,7 +786,7 @@ c-ts-base-mode
 
   ;; Electric
   (setq-local electric-indent-chars
-              (append "{}():;," electric-indent-chars))
+              (append "{}():;,#" electric-indent-chars))
 
   ;; Imenu.
   (setq-local treesit-simple-imenu-settings