From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!.POSTED.blaine.gmane.org!not-for-mail From: Alan Mackenzie Newsgroups: gmane.emacs.bugs Subject: bug#35254: 27.0.50; cc-mode/electric-pair-mode/electric-layout-mode: bad trailing whitespace behavior in cc-mode Date: Sat, 11 May 2019 12:05:24 +0000 Message-ID: <20190511120524.GA15991__9936.80583066947$1557576394$gmane$org@ACM> References: <87ftqms9db.fsf@secretsauce.net> <871s15k7ll.fsf@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Injection-Info: blaine.gmane.org; posting-host="blaine.gmane.org:195.159.176.226"; logging-data="235906"; mail-complaints-to="usenet@blaine.gmane.org" User-Agent: Mutt/1.10.1 (2018-07-13) Cc: Dima Kogan , 35254@debbugs.gnu.org, =?UTF-8?Q?Jo=C3=A3o_?= =?UTF-8?Q?T=C3=A1vora?= To: Noam Postavsky Original-X-From: bug-gnu-emacs-bounces+geb-bug-gnu-emacs=m.gmane.org@gnu.org Sat May 11 14:06:29 2019 Return-path: Envelope-to: geb-bug-gnu-emacs@m.gmane.org Original-Received: from lists.gnu.org ([209.51.188.17]) by blaine.gmane.org with esmtps (TLS1.0:RSA_AES_256_CBC_SHA1:256) (Exim 4.89) (envelope-from ) id 1hPQln-000zCB-5u for geb-bug-gnu-emacs@m.gmane.org; Sat, 11 May 2019 14:06:27 +0200 Original-Received: from localhost ([127.0.0.1]:58157 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1hPQlm-0003CV-6s for geb-bug-gnu-emacs@m.gmane.org; Sat, 11 May 2019 08:06:26 -0400 Original-Received: from eggs.gnu.org ([209.51.188.92]:45216) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1hPQlP-00034E-G8 for bug-gnu-emacs@gnu.org; Sat, 11 May 2019 08:06:04 -0400 Original-Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1hPQlO-0006nZ-0Q for bug-gnu-emacs@gnu.org; Sat, 11 May 2019 08:06:03 -0400 Original-Received: from debbugs.gnu.org ([209.51.188.43]:54703) by eggs.gnu.org with esmtps (TLS1.0:RSA_AES_128_CBC_SHA1:16) (Exim 4.71) (envelope-from ) id 1hPQlN-0006nR-RL; Sat, 11 May 2019 08:06:01 -0400 Original-Received: from Debian-debbugs by debbugs.gnu.org with local (Exim 4.84_2) (envelope-from ) id 1hPQlN-0004nJ-J8; Sat, 11 May 2019 08:06:01 -0400 X-Loop: help-debbugs@gnu.org Resent-From: Alan Mackenzie Original-Sender: "Debbugs-submit" Resent-CC: bug-gnu-emacs@gnu.org, bug-cc-mode@gnu.org Resent-Date: Sat, 11 May 2019 12:06:01 +0000 Resent-Message-ID: Resent-Sender: help-debbugs@gnu.org X-GNU-PR-Message: followup 35254 X-GNU-PR-Package: emacs,cc-mode Original-Received: via spool by 35254-submit@debbugs.gnu.org id=B35254.155757633018387 (code B ref 35254); Sat, 11 May 2019 12:06:01 +0000 Original-Received: (at 35254) by debbugs.gnu.org; 11 May 2019 12:05:30 +0000 Original-Received: from localhost ([127.0.0.1]:40014 helo=debbugs.gnu.org) by debbugs.gnu.org with esmtp (Exim 4.84_2) (envelope-from ) id 1hPQks-0004mV-2C for submit@debbugs.gnu.org; Sat, 11 May 2019 08:05:30 -0400 Original-Received: from colin.muc.de ([193.149.48.1]:60904 helo=mail.muc.de) by debbugs.gnu.org with smtp (Exim 4.84_2) (envelope-from ) id 1hPQkq-0004mK-Fk for 35254@debbugs.gnu.org; Sat, 11 May 2019 08:05:29 -0400 Original-Received: (qmail 13206 invoked by uid 3782); 11 May 2019 12:05:25 -0000 Original-Received: from acm.muc.de (p2E5D55A8.dip0.t-ipconnect.de [46.93.85.168]) by colin.muc.de (tmda-ofmipd) with ESMTP; Sat, 11 May 2019 14:05:24 +0200 Original-Received: (qmail 16092 invoked by uid 1000); 11 May 2019 12:05:24 -0000 Content-Disposition: inline In-Reply-To: <871s15k7ll.fsf@gmail.com> X-Delivery-Agent: TMDA/1.1.12 (Macallan) X-Primary-Address: acm@muc.de X-BeenThere: debbugs-submit@debbugs.gnu.org X-Mailman-Version: 2.1.18 Precedence: list X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] X-Received-From: 209.51.188.43 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.org@gnu.org Original-Sender: "bug-gnu-emacs" Xref: news.gmane.org gmane.emacs.bugs:159076 Archived-At: Hello, Noam. On Fri, May 10, 2019 at 23:12:06 -0400, Noam Postavsky wrote: > Dima Kogan writes: > > Hi. > > I'm seeing a regression introduced in 2019/01 by an update meant to make > > electric-pair-mode and electric-layout-mode play nicely: > > http://git.savannah.gnu.org/cgit/emacs.git/commit/?id=fd943124439b7644392919bca8bc2a77e6316d92 > > Recipe: > > 1. 'emacs -Q' with any emacs more recent than that patch > > 2. Open up tst.c that contains this: > > int main(int argc, char* argv[]) > > { > > return 0; > > } > > 3. Move the point to the beginning of the line containing "return 0" > > 4. RET RET RET RET RET > > Now there're a bunch of new lines between the { and the "return 0", as > > expected. But these lines aren't empty: they contain the initial > > indentation whitespace. This whitespace shouldn't be there; and it > > wasn't there prior to this patch. > Right, the problem is that electric-indent-inhibit only partially > disables electric indent, and the commit you reference changes which > parts. The patch below disables it more completely. Note however, that > this makes RET not do any electric indentation at all, just like in the > good old days of Emacs 24.3. I don't quite agree with this. The problem is confusion between effect 2 (below) and electric indentation. This effect 2 is fundamental editor functionality, and should be independent, MUST be independent of anything called "electric indentation". The two things are conceptually unrelated. > Possibly c-mode should rebind RET to a c-electric-return command or > something. CC Mode should be able to rely on the proper working of basic editor functionality. It shouldn't have to implement its own version of `newline'. > >>From 1103fdfbf2be55d68d44151498c2598fd622ac08 Mon Sep 17 00:00:00 2001 > From: Noam Postavsky > Date: Fri, 10 May 2019 16:40:27 -0400 > Subject: [PATCH] Inhibit electric indent completely in cc mode buffers > (Bug#35254) > Electric indent mode's post-self-insert hook entry has 3 effects: > 1. Indent the previous line. > 2. Remove trailing whitespace from the previous line. > 3. Indent the current line (when at beginning of line). > The change from 2019-01-22 "electric-layout-mode kicks in before > electric-pair-mode", makes 'electric-indent-inhibit' inhibit 1 and 2, > whereas before then it inhibited only 1. While cc mode provides its > own electric commands and therefore sets 'electric-indent-inhibit', it > doesn't implement an electric newline command. So if only one of > effects 2 and 3 from Electric indent mode occur, then hitting RET will > leave trailing whitespace. > * lisp/progmodes/cc-mode.el (c-electric-indent-mode-function): New > function. > (c-basic-common-init): Add it to electric-indent-functions to disable > electric indent completely (while still letting the > electric-indent-mode command/setting to control c-electric-flag as > before). > --- > lisp/progmodes/cc-mode.el | 5 +++++ > 1 file changed, 5 insertions(+) > diff --git a/lisp/progmodes/cc-mode.el b/lisp/progmodes/cc-mode.el > index bd62fc754a..e41f1101d0 100644 > --- a/lisp/progmodes/cc-mode.el > +++ b/lisp/progmodes/cc-mode.el > @@ -634,6 +634,7 @@ (defun c-basic-common-init (mode default-style) > ;; messing up CC Mode's, and set `c-electric-flag' if `electric-indent-mode' > ;; has been called by the user. > (when (boundp 'electric-indent-inhibit) (setq electric-indent-inhibit t)) > + (add-hook 'electric-indent-functions 'c-electric-indent-mode-function nil t) > ;; CC-mode should obey Emacs's generic preferences, tho only do it if > ;; Emacs's generic preferences can be set per-buffer (Emacs>=24.4). > (when (fboundp 'electric-indent-local-mode) > @@ -2143,6 +2144,10 @@ (defun c-electric-indent-local-mode-hook () > (setq c-electric-flag electric-indent-mode) > (c-update-modeline))) > +(defun c-electric-indent-mode-function (char) > + ;; We never want `electric-indent-mode' to do anything. > + 'no-indent) > + > > ;; Support for C I'm against this patch. It is an unpleasant workaround in CC Mode for problems in the Emacs core. CC Mode has set electric-indent-inhibit to t, and the Emacs core should respect that setting. Using electric-indent-functions in the way suggested couples CC Mode undesirably with electric indentation, possibly leading to future problems when electric indentation gets changed in the future. In previous Emacs versions (?23.x, ?24.x) there were two simple commands `newline' and `newline-and-indent'. As far as I remember, they both removed trailing WS from the "old" line, possibly as part of the filling which was done. They worked, and worked well. Why can't we get this functionality back again? > -- > 2.11.0 -- Alan Mackenzie (Nuremberg, Germany).