From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!.POSTED!not-for-mail From: Eli Zaretskii Newsgroups: gmane.emacs.bugs Subject: bug#31653: 26.1; comint-scroll-show-maximum-output nil regression Date: Wed, 30 May 2018 09:56:49 +0300 Message-ID: <53501D62-2054-4AEC-B2B9-2A2666A81BD7@gnu.org> References: <87k1rlbsaq.fsf@netris.org> NNTP-Posting-Host: blaine.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable X-Trace: blaine.gmane.org 1527663369 24267 195.159.176.226 (30 May 2018 06:56:09 GMT) X-Complaints-To: usenet@blaine.gmane.org NNTP-Posting-Date: Wed, 30 May 2018 06:56:09 +0000 (UTC) User-Agent: K-9 Mail for Android To: 31653@debbugs.gnu.org, mhw@netris.org Original-X-From: bug-gnu-emacs-bounces+geb-bug-gnu-emacs=m.gmane.org@gnu.org Wed May 30 08:56:05 2018 Return-path: Envelope-to: geb-bug-gnu-emacs@m.gmane.org Original-Received: from lists.gnu.org ([208.118.235.17]) by blaine.gmane.org with esmtp (Exim 4.84_2) (envelope-from ) id 1fNv1g-0006Cr-Va for geb-bug-gnu-emacs@m.gmane.org; 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Wed, 30 May 2018 02:56:53 -0400 In-Reply-To: <87k1rlbsaq.fsf@netris.org> X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.6.x 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: 208.118.235.43 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:146738 Archived-At: On May 30, 2018 8:56:13 AM GMT+03:00, Mark H Weaver wrot= e: > Emacs 26=2E1 has introduced a regression compared with 25=2E3 in the > handling of 'comint-scroll-show-maximum-output', which I prefer to set > to nil=2E Here's how to reproduce the problem: >=20 > * Run "emacs-26=2E1 -Q", with or without "-nw" as you prefer=2E > * M-x shell > * M-: (setq comint-scroll-show-maximum-output nil) > * Press RET repeatedly until the window starts scrolling=2E >=20 > Observe that after the point reaches the bottom of the window, it is > subsequently kept at the bottom of the window by aggressively > scrolling > one line at a time=2E >=20 > If you perform the same steps above with emacs-25=2E3, you'll see that > it > always recenters, so that scrolling occurs only once for every ~N/2 > lines of output, where N is the window height=2E >=20 > Note that (setq comint-scroll-show-maximum-output nil) still has some > effect=2E After performing the steps above, try this: >=20 > * C-l > * Press RET repeatedly until the window starts scrolling=2E > * M-: (setq comint-scroll-show-maximum-output t) > * C-l > * Press RET just once=2E >=20 > Observe that with 'comint-scroll-show-maximum-output' set to t, the > first RET after C-l immediately scrolls the window to show the maximum > output=2E >=20 > If you can suggest a workaround or a patch to fix this issue, I would > be > grateful=2E >=20 > Thanks very much for your work on Emacs=2E >=20 > Mark It's a deliberate change, by popular demand: shell-mode now sets scroll-conservatively to a large value locally in shell buffers=2E Reset that in your mode hook, and Bob's your uncle=2E If you are interested in the reasons for the change, see the log message of commit d7ac7b15ca9, it points to the relevant discussion=2E (This should have been in NEWS, sigh=2E=2E=2E)