Path: csiph.com!goblin1!goblin.stu.neva.ru!usenet.stanford.edu!not-for-mail From: Eli Zaretskii Newsgroups: gnu.emacs.bug Subject: bug#8155: 23.2; erratic cursor movement with visual-line-mode and wrap-prefix property Date: Thu, 03 Sep 2020 16:06:39 +0300 Lines: 47 Sender: "Debbugs-submit" Approved: bug-gnu-emacs@gnu.org Message-ID: References: <877hchfs23.fsf@gmail.com> <874koj24qs.fsf@gmx.net> <83pn73ui00.fsf@gnu.org> NNTP-Posting-Host: lists.gnu.org X-Trace: usenet.stanford.edu 1599138424 14236 209.51.188.17 (3 Sep 2020 13:07:04 GMT) X-Complaints-To: action@cs.stanford.edu Cc: 8155@debbugs.gnu.org, Yuan Fu , n.goaziou@gmail.com To: Stephen Berman Envelope-to: bug-gnu-emacs@gnu.org X-Loop: help-debbugs@gnu.org Resent-From: Eli Zaretskii Original-Sender: "Debbugs-submit" Resent-CC: bug-gnu-emacs@gnu.org Resent-Date: Thu, 03 Sep 2020 13:07:02 +0000 Resent-Message-ID: Resent-Sender: help-debbugs@gnu.org X-GNU-PR-Message: followup 8155 X-GNU-PR-Package: emacs X-GNU-PR-Keywords: In-Reply-To: <874koj24qs.fsf@gmx.net> (message from Stephen Berman on Sun, 30 Aug 2020 23:39:07 +0200) X-Spam-Score: -2.3 (--) X-BeenThere: debbugs-submit@debbugs.gnu.org X-Mailman-Version: 2.1.18 Precedence: list Errors-To: debbugs-submit-bounces@debbugs.gnu.org X-Spam-Score: -3.3 (---) 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: , X-Mailman-Original-Message-ID: <83pn73ui00.fsf@gnu.org> X-Mailman-Original-References: <877hchfs23.fsf@gmail.com> <874koj24qs.fsf@gmx.net> Xref: csiph.com gnu.emacs.bug:134829 > From: Stephen Berman > Date: Sun, 30 Aug 2020 23:39:07 +0200 > Cc: 8155@debbugs.gnu.org > > On Wed, 02 Mar 2011 16:41:40 +0100 Nicolas Goaziou wrote: > > > From `emacs -Q', C-x b whatever to open a new buffer. Then M-x > > visual-line-mode. Now fill a bit more than a screenfull of text without > > inserting a newline. Eventually use (put-text-property 1 (point-max) > > 'wrap-prefix " "). > > > > Now, going from (point-min), use C-n to move down. Near the end of that > > huge paragraph, C-n will not keep a constant column. In the same area, > > C-e and C-a will change line. C-p will go through the same path as C-n, > > thus not keeping the first column as well. > > I can reproduce this in GNU/Linux on current master (at commit 0bbc84630). I could not. Maybe the recipe needs to be more specific, e.g. to specify the text to be inserted. > - The erratic cursor movement also happens when visual-line-mode is > enabled _without_ adding the wrap-prefix property, and with much less > than a screenful of text: This I _could_ reproduce, but only on master. It was introduced by the changes that added support for word-wrap-by-category, which had a subtle logic error. So this bug is very recent, and almost certainly has nothing to do with the one discussed here from the beginning. That original bug was either solved long ago, or rears its ugly head only in some very subtle situations, which would explain why I cannot reproduce it. > I have also observed that the positions after C-n as reported above > may be differen when other commands intervenes (already noted with C-a > and C-e, but also e.g. sometimes 'M-: (point)'). > > - Using the mouse is also effected by visual-line-mode: All of the problems you describe are due to a single incorrect 'if' clause deep in the bowels of the display code. It should be fixed now. Thanks.