From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!.POSTED.blaine.gmane.org!not-for-mail From: Lars Ingebrigtsen Newsgroups: gmane.emacs.bugs Subject: bug#34720: 26.1; Reverting a GPG buffer moves all markers to the end of the file Date: Tue, 27 Aug 2019 09:14:22 +0200 Message-ID: <87v9uj2i7l.fsf@gnus.org> References: <87a7ic9due.fsf@gnu.org> <87muhnrwvs.fsf@mouse.gnus.org> <875zmk5r5u.fsf@gnus.org> <83sgpofjc9.fsf@gnu.org> <87k1b04a3x.fsf@gnus.org> <83pnksfel0.fsf@gnu.org> Mime-Version: 1.0 Content-Type: text/plain Injection-Info: blaine.gmane.org; posting-host="blaine.gmane.org:195.159.176.226"; logging-data="55292"; mail-complaints-to="usenet@blaine.gmane.org" User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/27.0.50 (gnu/linux) Cc: 34720@debbugs.gnu.org, dunni@gnu.org To: Eli Zaretskii Original-X-From: bug-gnu-emacs-bounces+geb-bug-gnu-emacs=m.gmane.org@gnu.org Tue Aug 27 09:15:19 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 (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.89) (envelope-from ) id 1i2VhE-000TpR-FC for geb-bug-gnu-emacs@m.gmane.org; Tue, 27 Aug 2019 09:15:16 +0200 Original-Received: from localhost ([::1]:47576 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1i2VhB-00028K-If for geb-bug-gnu-emacs@m.gmane.org; Tue, 27 Aug 2019 03:15:13 -0400 Original-Received: from eggs.gnu.org ([2001:470:142:3::10]:55032) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1i2Vh1-00027y-El for bug-gnu-emacs@gnu.org; Tue, 27 Aug 2019 03:15:04 -0400 Original-Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1i2Vh0-0001Po-83 for bug-gnu-emacs@gnu.org; Tue, 27 Aug 2019 03:15:03 -0400 Original-Received: from debbugs.gnu.org ([209.51.188.43]:38754) by eggs.gnu.org with esmtps (TLS1.0:RSA_AES_128_CBC_SHA1:16) (Exim 4.71) (envelope-from ) id 1i2Vh0-0001Pa-3j for bug-gnu-emacs@gnu.org; Tue, 27 Aug 2019 03:15:02 -0400 Original-Received: from Debian-debbugs by debbugs.gnu.org with local (Exim 4.84_2) (envelope-from ) id 1i2Vgz-00023l-Rt for bug-gnu-emacs@gnu.org; Tue, 27 Aug 2019 03:15:01 -0400 X-Loop: help-debbugs@gnu.org Resent-From: Lars Ingebrigtsen Original-Sender: "Debbugs-submit" Resent-CC: bug-gnu-emacs@gnu.org Resent-Date: Tue, 27 Aug 2019 07:15:01 +0000 Resent-Message-ID: Resent-Sender: help-debbugs@gnu.org X-GNU-PR-Message: followup 34720 X-GNU-PR-Package: emacs X-GNU-PR-Keywords: confirmed Original-Received: via spool by 34720-submit@debbugs.gnu.org id=B34720.15668900687841 (code B ref 34720); Tue, 27 Aug 2019 07:15:01 +0000 Original-Received: (at 34720) by debbugs.gnu.org; 27 Aug 2019 07:14:28 +0000 Original-Received: from localhost ([127.0.0.1]:47571 helo=debbugs.gnu.org) by debbugs.gnu.org with esmtp (Exim 4.84_2) (envelope-from ) id 1i2VgS-00022P-Gy for submit@debbugs.gnu.org; Tue, 27 Aug 2019 03:14:28 -0400 Original-Received: from quimby.gnus.org ([80.91.231.51]:37634) by debbugs.gnu.org with esmtp (Exim 4.84_2) (envelope-from ) id 1i2VgQ-00022F-Pi for 34720@debbugs.gnu.org; Tue, 27 Aug 2019 03:14:27 -0400 Original-Received: from cm-84.212.202.86.getinternet.no ([84.212.202.86] helo=marnie) by quimby.gnus.org with esmtpsa (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.89) (envelope-from ) id 1i2VgM-0004Zg-Id; Tue, 27 Aug 2019 09:14:25 +0200 In-Reply-To: <83pnksfel0.fsf@gnu.org> (Eli Zaretskii's message of "Mon, 26 Aug 2019 12:42:03 +0300") 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:173342 Eli Zaretskii writes: > IOW, there's no guarantee that markers will be preserved across > operations that replace text. No, but we have a small handful of functions that do best effort... but they're deep in the C code and not accessible. Finsert_file_contents has this: /* Replacement should preserve point as it preserves markers. */ if (!NILP (replace)) { window_markers = get_window_points_and_markers (); record_unwind_protect (restore_point_unwind, XCAR (XCAR (window_markers))); } ... handled: if (inserted > 0) restore_window_points (window_markers, inserted, BYTE_TO_CHAR (same_at_start), same_at_end_charpos); The problem that this bug report addresses is that Lisp level functions that implement special handlers for insert-file-contents (in this case, epa-file-insert-file-contents) doesn't have access to the internals necessary to give the user the same experience that the built-in version gives the user. My suggestion is basically to make DEFUN shims over get_window_points_and_markers/restore_window_points, and create a new macro `with-saved-markers' that would use that pair to do this cheap, best-effort thing that Finsert_file_contents does. > But I'm not opposed to adding support for string as the source for > replacement. Just be aware that the code which access such a string > must be highly optimized, because it is executed in the innermost loop > of the code. I just had a peek at the code, and it indeed highly optimised... >> No wonder this function has gotten one single usage after it was >> introduced two years ago. (Well, one usage to >> replace-region-contents, which then calls the function.) (Unless >> I'm grepping wrong.) > > replace-region-contents is used in json.el. Yes, that's the one single usage of this machinery. -- (domestic pets only, the antidote for overdose, milk.) bloggy blog: http://lars.ingebrigtsen.no