Re: [PATCH] lisp-mode: fix defstruct docstring identification for Common Lisp

[Nicolas Martyanoff]

Eli Zaretskii <eliz@gnu.org> writes:

>> From: Nicolas Martyanoff <nicolas@n16f.net>
>> Cc: Nicolas Martyanoff <nicolas@n16f.net>
>> Date: Tue, 31 Jan 2023 01:54:57 +0100
>> 
>> In Common Lisp, defstruct accepts a docstring in second position. Having the
>> docstring identified as such allows correct highlighting.
>
> Do you mean cl-defstruct?  If not, what do you mean?
>
> Can you show a small Lisp recipe to demonstrate the differences in
> highlighting before and after the change?

I do mean in Common Lisp.

To reproduce the issue (tested on Emacs 28.2 with "emacs -q"):

- Create a test.lisp buffer. It will use `lisp-mode' (the Common Lisp
  "variant", not sure about the right terminology).

- Declare a structure:
  (defstruct point "A 2d point." x y)

- Check that the face used for the docstring is (incorrectly)
  `font-lock-string-face'.

- Update the doc-string-elt property for 'defstruct to indicate that the
  second argument is the docstring, and reset highlighting
  M-: (put 'defstruct 'doc-string-elt 2)
  M-x common-lisp-mode

- Check that the face used for the docstring is now `font-lock-doc-face'
  as it should be.

Regards,

-- 
Nicolas Martyanoff
https://n16f.net
nicolas@n16f.net