From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!not-for-mail From: Toby Cubitt Newsgroups: gmane.emacs.bugs Subject: bug#16377: Undo Tree regression: (error "Unrecognized entry in undo list undo-tree-canary") Date: Wed, 22 Jan 2014 21:30:34 +0000 Message-ID: <20140122213034.GA18257@c3po> References: NNTP-Posting-Host: plane.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-Trace: ger.gmane.org 1390426268 826 80.91.229.3 (22 Jan 2014 21:31:08 GMT) X-Complaints-To: usenet@ger.gmane.org NNTP-Posting-Date: Wed, 22 Jan 2014 21:31:08 +0000 (UTC) Cc: 16377@debbugs.gnu.org, gundaetiapo@gmail.com To: Stefan Monnier Original-X-From: bug-gnu-emacs-bounces+geb-bug-gnu-emacs=m.gmane.org@gnu.org Wed Jan 22 22:31:14 2014 Return-path: Envelope-to: geb-bug-gnu-emacs@m.gmane.org Original-Received: from lists.gnu.org ([208.118.235.17]) by plane.gmane.org with esmtp (Exim 4.69) (envelope-from ) id 1W65OD-00017G-T8 for geb-bug-gnu-emacs@m.gmane.org; Wed, 22 Jan 2014 22:31:14 +0100 Original-Received: from localhost ([::1]:37610 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1W65OD-0003OM-Gi for geb-bug-gnu-emacs@m.gmane.org; Wed, 22 Jan 2014 16:31:13 -0500 Original-Received: from eggs.gnu.org ([2001:4830:134:3::10]:49219) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1W65O6-0003OE-UC for bug-gnu-emacs@gnu.org; Wed, 22 Jan 2014 16:31:11 -0500 Original-Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1W65O2-0006Zw-JO for bug-gnu-emacs@gnu.org; Wed, 22 Jan 2014 16:31:06 -0500 Original-Received: from debbugs.gnu.org ([140.186.70.43]:46984) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1W65O2-0006Zq-Fs for bug-gnu-emacs@gnu.org; Wed, 22 Jan 2014 16:31:02 -0500 Original-Received: from Debian-debbugs by debbugs.gnu.org with local (Exim 4.80) (envelope-from ) id 1W65O1-00047N-SO for bug-gnu-emacs@gnu.org; Wed, 22 Jan 2014 16:31:02 -0500 X-Loop: help-debbugs@gnu.org Resent-From: Toby Cubitt Original-Sender: "Debbugs-submit" Resent-CC: bug-gnu-emacs@gnu.org Resent-Date: Wed, 22 Jan 2014 21:31:01 +0000 Resent-Message-ID: Resent-Sender: help-debbugs@gnu.org X-GNU-PR-Message: followup 16377 X-GNU-PR-Package: emacs X-GNU-PR-Keywords: Original-Received: via spool by 16377-submit@debbugs.gnu.org id=B16377.139042624315804 (code B ref 16377); Wed, 22 Jan 2014 21:31:01 +0000 Original-Received: (at 16377) by debbugs.gnu.org; 22 Jan 2014 21:30:43 +0000 Original-Received: from localhost ([127.0.0.1]:32770 helo=debbugs.gnu.org) by debbugs.gnu.org with esmtp (Exim 4.80) (envelope-from ) id 1W65Ni-00046q-II for submit@debbugs.gnu.org; Wed, 22 Jan 2014 16:30:42 -0500 Original-Received: from starfish.geekisp.com ([216.168.135.166]:45234) by debbugs.gnu.org with smtp (Exim 4.80) (envelope-from ) id 1W65Ng-00046i-8d for 16377@debbugs.gnu.org; Wed, 22 Jan 2014 16:30:40 -0500 Original-Received: (qmail 18066 invoked by uid 1003); 22 Jan 2014 21:30:39 -0000 Original-Received: from localhost (localhost.geekisp.com [127.0.0.1]) by localhost.geekisp.com (tmda-ofmipd) with ESMTP; Wed, 22 Jan 2014 16:30:36 -0500 Content-Disposition: inline In-Reply-To: X-PGP-Key: http://www.dr-qubit.org/gpg-toby-pub.asc User-Agent: Mutt/1.5.22 (2013-10-16) X-Delivery-Agent: TMDA/1.1.11 (Ladyburn) X-Primary-Address: toby@dr-qubit.org X-BeenThere: debbugs-submit@debbugs.gnu.org X-Mailman-Version: 2.1.15 Precedence: list X-detected-operating-system: by eggs.gnu.org: GNU/Linux 3.x X-Received-From: 140.186.70.43 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-bounces+geb-bug-gnu-emacs=m.gmane.org@gnu.org Xref: news.gmane.org gmane.emacs.bugs:83901 Archived-At: On Wed, Jan 22, 2014 at 01:56:12PM -0500, Stefan Monnier wrote: > > Are there circumstances in which `primitive-undo' doesn't add to > > `buffer-undo-list'? > > Of course: if there are no changes until the next undo boundary, then > primitive-undo just doesn't do anything other than pop that > undo boundary. > And primitive-undo doesn't add any boundary, so it can end up with no > change at all to buffer-undo-list. Makes sense. This shouldn't happen in undo-tree, since normally it should only call `primitive-undo' on a non-empty undo changeset...except it's just possible that undo-tree's undo-in-region could add empty changesets to buffer-undo-tree under some circumstances. Which might explain why this error is triggered by undo-in-region, but not in normal undo-tree usage. I'll investigate when I have time. In any case, it seems clear to me that it's an existing undo-tree bug that's been brought to light by the new error checking, rather than breakage from the new `primitive-undo' implementation. So the ball's in my court. Toby -- Dr T. S. Cubitt Royal Society University Research Fellow and Fellow of Churchill College, Cambridge Centre for Quantum Information DAMTP, University of Cambridge email: tsc25@cantab.net web: www.dr-qubit.org