From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.io!.POSTED.blaine.gmane.org!not-for-mail From: Eli Zaretskii Newsgroups: gmane.emacs.bugs Subject: bug#50983: 28.0.50; [REGRESSION, BUG] Display bugs with uncommon characters Date: Mon, 04 Oct 2021 16:50:15 +0300 Message-ID: <83y2786grs.fsf@gnu.org> References: <83lf3aac5w.fsf@gnu.org> <835yuea0gb.fsf@gnu.org> <83wnmu8irr.fsf@gnu.org> <83h7dx6k0q.fsf@gnu.org> Injection-Info: ciao.gmane.io; posting-host="blaine.gmane.org:116.202.254.214"; logging-data="14500"; mail-complaints-to="usenet@ciao.gmane.io" Cc: 50983@debbugs.gnu.org, alan@idiocy.org To: rudiwillalwaysloveyou@gmail.com Original-X-From: bug-gnu-emacs-bounces+geb-bug-gnu-emacs=m.gmane-mx.org@gnu.org Mon Oct 04 16:07:06 2021 Return-path: Envelope-to: geb-bug-gnu-emacs@m.gmane-mx.org Original-Received: from lists.gnu.org ([209.51.188.17]) by ciao.gmane.io with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1mXOcU-0003Re-B4 for geb-bug-gnu-emacs@m.gmane-mx.org; Mon, 04 Oct 2021 16:07:06 +0200 Original-Received: from localhost ([::1]:46170 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1mXOcO-0004ku-8A for geb-bug-gnu-emacs@m.gmane-mx.org; Mon, 04 Oct 2021 10:07:00 -0400 Original-Received: from eggs.gnu.org ([2001:470:142:3::10]:39868) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1mXOMw-0003NR-Cf for bug-gnu-emacs@gnu.org; Mon, 04 Oct 2021 09:51:02 -0400 Original-Received: from debbugs.gnu.org ([209.51.188.43]:52658) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.90_1) (envelope-from ) id 1mXOMw-0003s3-3v for bug-gnu-emacs@gnu.org; Mon, 04 Oct 2021 09:51:02 -0400 Original-Received: from Debian-debbugs by debbugs.gnu.org with local (Exim 4.84_2) (envelope-from ) id 1mXOMw-0003tg-28 for bug-gnu-emacs@gnu.org; Mon, 04 Oct 2021 09:51:02 -0400 X-Loop: help-debbugs@gnu.org Resent-From: Eli Zaretskii Original-Sender: "Debbugs-submit" Resent-CC: bug-gnu-emacs@gnu.org Resent-Date: Mon, 04 Oct 2021 13:51:02 +0000 Resent-Message-ID: Resent-Sender: help-debbugs@gnu.org X-GNU-PR-Message: followup 50983 X-GNU-PR-Package: emacs Original-Received: via spool by 50983-submit@debbugs.gnu.org id=B50983.163335545414964 (code B ref 50983); Mon, 04 Oct 2021 13:51:02 +0000 Original-Received: (at 50983) by debbugs.gnu.org; 4 Oct 2021 13:50:54 +0000 Original-Received: from localhost ([127.0.0.1]:35971 helo=debbugs.gnu.org) by debbugs.gnu.org with esmtp (Exim 4.84_2) (envelope-from ) id 1mXOMn-0003tH-OG for submit@debbugs.gnu.org; Mon, 04 Oct 2021 09:50:54 -0400 Original-Received: from eggs.gnu.org ([209.51.188.92]:34626) by debbugs.gnu.org with esmtp (Exim 4.84_2) (envelope-from ) id 1mXOMj-0003t1-Q4 for 50983@debbugs.gnu.org; Mon, 04 Oct 2021 09:50:51 -0400 Original-Received: from fencepost.gnu.org ([2001:470:142:3::e]:54552) by eggs.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1mXOMd-00039G-5B; Mon, 04 Oct 2021 09:50:43 -0400 Original-Received: from 84.94.185.95.cable.012.net.il ([84.94.185.95]:1450 helo=home-c4e4a596f7) by fencepost.gnu.org with esmtpsa (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1mXOMX-0004Xz-RZ; Mon, 04 Oct 2021 09:50:43 -0400 In-Reply-To: <83h7dx6k0q.fsf@gnu.org> (message from Eli Zaretskii on Mon, 04 Oct 2021 15:40:05 +0300) X-BeenThere: debbugs-submit@debbugs.gnu.org X-Mailman-Version: 2.1.18 Precedence: list X-BeenThere: bug-gnu-emacs@gnu.org List-Id: "Bug reports for GNU Emacs, the Swiss army knife of text editors" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: bug-gnu-emacs-bounces+geb-bug-gnu-emacs=m.gmane-mx.org@gnu.org Original-Sender: "bug-gnu-emacs" Xref: news.gmane.io gmane.emacs.bugs:216357 Archived-At: > Date: Mon, 04 Oct 2021 15:40:05 +0300 > From: Eli Zaretskii > Cc: 50983@debbugs.gnu.org, alan@idiocy.org > > > From: Rudi C > > Date: Mon, 4 Oct 2021 11:35:41 +0330 > > Cc: Alan Third , 50983@debbugs.gnu.org > > > > But the problem does not happen with vim (nor with emacs 27 for `weird.txt`), so it is clearly an interaction > > of different elements. > > > > Anyhow, I have opened an [upstream issue](https://github.com/kovidgoyal/kitty/issues/4094). Please > > subscribe to it so that you might offer your emacs expertise there, if needed. > > I subscribed and posted the following comment: > > Emacs uses character width tables computed from the latest Unicode > Standard version 14.0.0, using the data in the file > EastAsianWidth.txt. In that text, the U+00AD SOFT HYPHEN character, > which caused the problems in your file, has the East Asian Width > property value of A, which stands for "Ambiguous". The definition of > this value in the Unicode Standard Annex 11 (UAX#11) is as follows: > > East Asian Ambiguous (A): All characters that can be sometimes wide > and sometimes narrow. Ambiguous characters require additional > information not contained in the character code to further resolve > their width. > > Ambiguous characters occur in East Asian legacy character sets as > wide characters, but as narrow (i.e., normal-width) characters in > non-East Asian usage. > > And since the file you show didn't have any East Asian legacy > characters, treating SOFT HYPHEN as narrow is IMO correct. To summarize the comments there: The problematic character in the first example is U+00AD SOFT HYPHEN. Kitty assumes that character is never rendered, and therefore effectively treats it as zero-width character. I don't see how Emacs display can possibly work correctly on such a terminal, so I think we should close this bug report as "notabug". For the second example, I think there could be an issue with character compositions on this terminal, so the OP is advised to try turning off auto-composition-mode. If that solves the problem, fine; if not, I guess Kitty once again assumes something about how such sequences are rendered, and those assumptions don't fit how Emacs displays them in reality, and if so, that problem, too, has no satisfactory solution (and isn't an Emacs bug).