bug#66970: 29.1; Overwrite-mode is not working with Korean characters

[Sukbeom Kim]

Thanks for the patch.

It seems that the issue within the overwrite-mode can be resolved with
the patch.

Anyway, I have one more question. I think there is a similar issue with
org-edit-special (table.el). I thought it would be resolved if the
overwrite-mode was fixed but it seems not.

Should I report it with a new bug ticket? Or can I describe it in this
ticket?

Eli Zaretskii <eliz@gnu.org> writes:

>> From: João Távora <joaotavora@gmail.com>
>> Date: Thu, 9 Nov 2023 16:37:17 +0000
>>
>> Eli brought up this bug in emacs-devel and I thought
>> I would give it a shot.
>>
>> I had never touched this code or anything like it, but I do
>> use input methods a bit for portuguese.  Let me know what
>> you think.
>
> Thanks.
>
> Sukbeom, could you please try the patch and see if it gives good
> results, both with and without Overwrite mode?
>
>> diff --git a/lisp/leim/quail/hangul.el b/lisp/leim/quail/hangul.el
>> index 46a2e5a6ba2..7e6c7310179 100644
>> --- a/lisp/leim/quail/hangul.el
>> +++ b/lisp/leim/quail/hangul.el
>> @@ -146,21 +146,34 @@ hangul-insert-character
>>        (progn
>>          (delete-region (region-beginning) (region-end))
>>          (deactivate-mark)))
>> -  (quail-delete-region)
>> -  (let ((first (car queues)))
>> -    (insert
>> -     (hangul-character
>> -      (+ (aref first 0) (hangul-djamo 'cho (aref first 0) (aref first 1)))
>> -      (+ (aref first 2) (hangul-djamo 'jung (aref first 2) (aref first 3)))
>> -      (+ (aref first 4) (hangul-djamo 'jong (aref first 4) (aref first 
>> 5))))))
>> -  (move-overlay quail-overlay (overlay-start quail-overlay) (point))
>> -  (dolist (queue (cdr queues))
>> -    (insert
>> -     (hangul-character
>> -      (+ (aref queue 0) (hangul-djamo 'cho (aref queue 0) (aref queue 1)))
>> -      (+ (aref queue 2) (hangul-djamo 'jung (aref queue 2) (aref queue 3)))
>> -      (+ (aref queue 4) (hangul-djamo 'jong (aref queue 4) (aref queue 
>> 5)))))
>> -    (move-overlay quail-overlay (1+ (overlay-start quail-overlay)) 
>> (point))))
>> +  (let* ((chars-to-insert
>> +          (with-temp-buffer
>> +            (dolist (queue queues (mapcar #'identity (buffer-string)))
>> +              (insert
>> +               (hangul-character
>> +                (+ (aref queue 0) (hangul-djamo 'cho (aref queue 0)
>> (aref queue 1)))
>> +                (+ (aref queue 2) (hangul-djamo 'jung (aref queue 2)
>> (aref queue 3)))
>> +                (+ (aref queue 4) (hangul-djamo 'jong (aref queue 4)
>> (aref queue 5))))))))
>> +         (may-have-to-overwrite-p
>> +          (or
>> +           ;; If the overlay isn't showing (i.e. it has 0 length) then
>> +           ;; we may want to insert char overwriting (iff overwrite-mode is
>> +           ;; non-nil, of course)
>> +           (= (overlay-start quail-overlay) (overlay-end quail-overlay))
>> +           ;; Likewise we want to do it if there is more then one
>> +           ;; character that were combined.
>> +           (cdr chars-to-insert))))
>> +    (quail-delete-region) ; this kills the overlay
>> +    (dolist (c chars-to-insert)
>> +      (let ((last-command-event c)
>> +            (overwrite-mode (and overwrite-mode
>> +                                 may-have-to-overwrite-p
>> +                                 overwrite-mode)))
>> +        (self-insert-command 1)
>> +        ;; TODO: maybe use cl-loop for an easier-to-read loop?
>> +        (setq may-have-to-overwrite-p nil)))
>> +    ; this revives it (TODO: do we really always revive?)
>> +    (move-overlay quail-overlay (1- (point)) (point))))
>>
>>  (defun hangul-djamo (jamo char1 char2)
>>    "Return the double Jamo index calculated from the arguments.
>>
>>
>>
>> --
>> João Távora
>>