bug#23814: 24.5; bug of hz coding-system

[Eli Zaretskii <eliz@gnu.org>]

Ping!  Could you please try this patch and see if it solves the
problem?

> From: handa <handa@gnu.org>
> Cc: ynyaaa@gmail.com, 23814@debbugs.gnu.org
> Date: Wed, 13 Jul 2016 23:12:47 +0900
> 
> > > > >> `encode-hz-region' uses `iso-2022-7bit' coding-system internally,
> > > > >> replacing it with the coding-system below will work.
> > > > >> 
> > > > >> (define-coding-system 'iso-2022-cn-gb
> > > > >>   "ISO 2022 based 7bit encoding only for Chinese GB2312."
> > > > >>   :coding-type 'iso-2022
> > > > >>   :mnemonic ?C
> > > > >>   :charset-list '(ascii chinese-gb2312)
> > > > >>   :designation [(ascii chinese-gb2312) nil nil nil]
> > > > >>   :flags '(ascii-at-eol ascii-at-cntl designation 7-bit safe)
> > > > >>   )
> 
> Right.  But, as there are already so many iso-2022 based coding systems,
> I'd like to avoid adding a new one just for encode-hz-region.  I think
> the attached patch is sufficent.  Could you please try it?  It also
> fixes the problem of incorrect decoding of "~{7~~}".
> 
> ---
> K. Handa
> handa@gnu.org
> 
> diff --git a/lisp/language/china-util.el b/lisp/language/china-util.el
> index e531640..9735bd6 100644
> --- a/lisp/language/china-util.el
> +++ b/lisp/language/china-util.el
> @@ -95,7 +95,9 @@ decode-hz-region
>  	(goto-char (point-min))
>  	(while (search-forward "~" nil t)
>  	  (setq ch (following-char))
> -	  (if (or (= ch ?\n) (= ch ?~)) (delete-char -1)))
> +          (if (= ch ?{)
> +              (search-forward "~}" nil 'move)
> +            (if (or (= ch ?\n) (= ch ?~)) (delete-char -1))))
>  
>  	;; "^zW...\n" -> Chinese GB2312
>  	;; "~{...~}"  -> Chinese GB2312
> @@ -141,7 +143,7 @@ encode-hz-region
>    (save-excursion
>      (save-restriction
>        (narrow-to-region beg end)
> -
> +      (put-text-property beg end 'charset 'chinese-gb2312)
>        ;; "~" -> "~~"
>        (goto-char (point-min))
>        (while (search-forward "~" nil t)	(insert ?~))
> 
>