bug#39820: wrong face is assigned to comment delimiter in lisp-mode

bug#39820: wrong face is assigned to comment delimiter in lisp-mode

[chuntaro]

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Start emacs -Q and evaluate the following with *scratch*.

(set-face-foreground 'font-lock-comment-face "green")
(set-face-foreground 'font-lock-comment-delimiter-face "red")

Open `foo.lisp' with C-x C-f and enter as follows.

#|
comment
|#

As a result, the correct face is not assigned to the closing delimiter.

#|      <- font-lock-comment-delimiter-face
comment <- font-lock-comment-face
|#      <- font-lock-comment-face <- Wrong face

Occurs in Emacs 25.2, 26.1 and 27.0.60.

Normally, both colors are the same, so no one may have noticed until now.
I noticed recently because I was using a zenburn theme with slightly
different colors.

-- 
chuntaro

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bug#39820: wrong face is assigned to comment delimiter in lisp-mode

[Lars Ingebrigtsen]

chuntaro@sakura-games.jp writes:

> As a result, the correct face is not assigned to the closing delimiter.
>
> #|      <- font-lock-comment-delimiter-face
> comment <- font-lock-comment-face
> |#      <- font-lock-comment-face <- Wrong face
>
> Occurs in Emacs 25.2, 26.1 and 27.0.60.

Thanks for the clear recipe for reproduction.

This should now be fixed in Emacs 28.

-- 
(domestic pets only, the antidote for overdose, milk.)
   bloggy blog: http://lars.ingebrigtsen.no

bug#39820: wrong face is assigned to comment delimiter in lisp-mode

[Lars Ingebrigtsen]

Lars Ingebrigtsen <larsi@gnus.org> writes:

> chuntaro@sakura-games.jp writes:
>
>> As a result, the correct face is not assigned to the closing delimiter.
>>
>> #|      <- font-lock-comment-delimiter-face
>> comment <- font-lock-comment-face
>> |#      <- font-lock-comment-face <- Wrong face
>>
>> Occurs in Emacs 25.2, 26.1 and 27.0.60.
>
> Thanks for the clear recipe for reproduction.
>
> This should now be fixed in Emacs 28.

The fix wasn't the correct one (leading to M-; inserting |#), so I've
reverted it for now, and I'm reopening this bug report.

-- 
(domestic pets only, the antidote for overdose, milk.)
   bloggy blog: http://lars.ingebrigtsen.no

bug#39820: wrong face is assigned to comment delimiter in lisp-mode

[Lars Ingebrigtsen]

chuntaro <chuntaro@sakura-games.jp> writes:

> I think I was able to fix #39820 by doing the following.

Thanks; that fixes the problem here too, so I've pushed this to Emacs
28.

This change was small enough to apply without assigning copyright to the
FSF, but for future patches you want to submit, it might make sense to
get the paperwork started now, so that subsequent patches can be applied
speedily. Would you be willing to sign such paperwork?

-- 
(domestic pets only, the antidote for overdose, milk.)
   bloggy blog: http://lars.ingebrigtsen.no