From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!not-for-mail From: Stefan Monnier Newsgroups: gmane.emacs.bugs Subject: bug#10047: Looking for help debugging an undo issue Date: Fri, 18 Nov 2011 12:36:23 -0500 Message-ID: References: <4EC0F2F3.5000607@orcon.net.nz> NNTP-Posting-Host: lo.gmane.org Mime-Version: 1.0 Content-Type: text/plain X-Trace: dough.gmane.org 1321637836 11322 80.91.229.12 (18 Nov 2011 17:37:16 GMT) X-Complaints-To: usenet@dough.gmane.org NNTP-Posting-Date: Fri, 18 Nov 2011 17:37:16 +0000 (UTC) Cc: 10047@debbugs.gnu.org To: Phil Sainty Original-X-From: bug-gnu-emacs-bounces+geb-bug-gnu-emacs=m.gmane.org@gnu.org Fri Nov 18 18:37:11 2011 Return-path: Envelope-to: geb-bug-gnu-emacs@m.gmane.org Original-Received: from lists.gnu.org ([140.186.70.17]) by lo.gmane.org with esmtp (Exim 4.69) (envelope-from ) id 1RRSNA-0004lZ-PY for geb-bug-gnu-emacs@m.gmane.org; Fri, 18 Nov 2011 18:37:08 +0100 Original-Received: from localhost ([::1]:34211 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1RRSNA-0003zi-AW for geb-bug-gnu-emacs@m.gmane.org; Fri, 18 Nov 2011 12:37:08 -0500 Original-Received: from eggs.gnu.org ([140.186.70.92]:41188) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1RRSN7-0003yn-FY for bug-gnu-emacs@gnu.org; Fri, 18 Nov 2011 12:37:06 -0500 Original-Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1RRSN6-0006bz-GJ for bug-gnu-emacs@gnu.org; Fri, 18 Nov 2011 12:37:05 -0500 Original-Received: from debbugs.gnu.org ([140.186.70.43]:55489) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1RRSN6-0006bv-EN for bug-gnu-emacs@gnu.org; Fri, 18 Nov 2011 12:37:04 -0500 Original-Received: from Debian-debbugs by debbugs.gnu.org with local (Exim 4.69) (envelope-from ) id 1RRSO1-0000ye-QC for bug-gnu-emacs@gnu.org; Fri, 18 Nov 2011 12:38:01 -0500 X-Loop: help-debbugs@gnu.org Resent-From: Stefan Monnier Original-Sender: debbugs-submit-bounces@debbugs.gnu.org Resent-CC: bug-gnu-emacs@gnu.org Resent-Date: Fri, 18 Nov 2011 17:38:01 +0000 Resent-Message-ID: Resent-Sender: help-debbugs@gnu.org X-GNU-PR-Message: followup 10047 X-GNU-PR-Package: emacs X-GNU-PR-Keywords: Original-Received: via spool by 10047-submit@debbugs.gnu.org id=B10047.13216378523683 (code B ref 10047); Fri, 18 Nov 2011 17:38:01 +0000 Original-Received: (at 10047) by debbugs.gnu.org; 18 Nov 2011 17:37:32 +0000 Original-Received: from localhost ([127.0.0.1] helo=debbugs.gnu.org) by debbugs.gnu.org with esmtp (Exim 4.69) (envelope-from ) id 1RRSNY-0000xJ-KO for submit@debbugs.gnu.org; Fri, 18 Nov 2011 12:37:32 -0500 Original-Received: from ironport2-out.teksavvy.com ([206.248.154.181]) by debbugs.gnu.org with esmtp (Exim 4.69) (envelope-from ) id 1RRSNN-0000wu-ON for 10047@debbugs.gnu.org; Fri, 18 Nov 2011 12:37:22 -0500 X-IronPort-Anti-Spam-Filtered: true X-IronPort-Anti-Spam-Result: Av0EACyXxk5FpZVk/2dsb2JhbABDqjGBBoFyAQEEAVYjBQsLDiYSFBgNEAETiBa2e4oXBIgXmXeESg X-IronPort-AV: E=Sophos;i="4.69,534,1315195200"; d="scan'208";a="148502677" Original-Received: from 69-165-149-100.dsl.teksavvy.com (HELO pastel.home) ([69.165.149.100]) by ironport2-out.teksavvy.com with ESMTP/TLS/ADH-AES256-SHA; 18 Nov 2011 12:36:23 -0500 Original-Received: by pastel.home (Postfix, from userid 20848) id 4536E5936A; Fri, 18 Nov 2011 12:36:23 -0500 (EST) In-Reply-To: <4EC0F2F3.5000607@orcon.net.nz> (Phil Sainty's message of "Mon, 14 Nov 2011 23:52:35 +1300") User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/24.0.91 (gnu/linux) X-BeenThere: debbugs-submit@debbugs.gnu.org X-Mailman-Version: 2.1.11 Precedence: list Resent-Date: Fri, 18 Nov 2011 12:38:01 -0500 X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.6 (newer, 2) 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:54044 Archived-At: > I'm a bit stumped, and am not even sure how to approach this. > I'm writing a major mode for entering timesheet data for use with a > custom application, and I wanted to keep the columns automatically > aligned within a block of entries for a given day, so my mode uses > `post-command-hook' to (most of the time) call `align-current', which > works more or less as I want* except that I'm encountering situations > in testing where the undo system forgets some of the history and just > reports "No further undo information". This is happening when I delete > a few lines of data, and then try to re-do it all. It gets part way > through and then fails to re-do the remainder. This is something of a > show-stopper. > I'm seeing the same issue with both Emacs 23.3 and 24.0.91.1 on both > Windows and Ubuntu. > I'm really not sure how to go about debugging the problem. I was > hoping that maybe someone can provide some insight into how my use of > align-current and post-command-hook might affect the undo system, or > otherwise suggest some smart ways of narrowing down what the problem > is? I'm really not familiar with the inner workings of the mechanisms > in question. All I can think of offhand is that (despite the test data > being only ~200 bytes) I'm managing to exceed the maximum amount of > undo data permitted, and it's silently losing the data for the older > changes?? Your problem doesn't ring a bell, sorry. The best options I can think of are: - log the value of buffer-undo-list at each step in some auxiliary debugging buffer, for post-mortem analysis. - try to come up with a reproducible test case. Stefan