Re: master 15afa72460b: Fix 'script-representative-chars' for the 'han' script

[Eli Zaretskii <eliz@gnu.org>]

> From: Po Lu <luangruo@yahoo.com>
> Cc: emacs-devel@gnu.org
> Date: Sun, 04 Aug 2024 08:16:20 +0800
> 
> >> > --- a/lisp/international/fontset.el
> >> > +++ b/lisp/international/fontset.el
> >> > @@ -208,8 +208,7 @@
> >> >  	(kana #x304B)
> >> >  	(bopomofo #x3105)
> >> >  	(kanbun #x319D)
> >> > -	(han #x2e90 #x2f00 #x3010 #x3200 #x3300 #x3400 #x31c0 #x4e10
> >> > -             #x5B57 #xfe30 #xf900)
> >> > +	(han #x2e90 #x2f00 #x3200 #x3300 #x3400 #x4e10 #x5B57 #xfe30 #xf900)
> >> 
> >> Someone reports that this set of characters still does not enable the
> >> detection of WenQuanYi Micro Hei, which is certainly complete enough to
> >> display all Han text that will be encountered in practice.  U+2E90,
> >> U+2F00, U+3300 and U+3400 are absent from this font, and quite
> >> reasonably so, since they are freestanding radicals, Kana, which belong
> >> in the entry for kana rather than han, or obsolete.
> >
> > On what system did that happen?
> 
> Not "what system", "which font": WenQuanYi Micro Hei, one of the better
> free Han fonts.

If you remove U+2E90, U+2F00, U+3300 and U+3400 from the list and
rebuild Emacs, what happens if you insert U+2F75?  Does Emacs succeed
to find another font which support that codepoint or does it appear as
tofu?  If the latter, what happens if you in install some additional
font which does support U+2F75?

IOW, I'm interested to know what happens on GNU/Linux if more than one
font is available that together cover both the "usual" han characters
and those additional ones which you think we should remove from
script-representative-chars, but neither of these fonts supports all
of those characters.  Can Emacs solve this by itself on GNU/Linux, or
does it need "help" from the user's customization of the fontset?