Subject: scroll-conservatively==1 not honored for fast line by line navigation up

From: Barry OReilly <[email-masked]>
Date: Wed, 29 May 2013 18:58:33 -0400

Let /tmp/scroll-conservatively-1.el have this content:

  (setq scroll-conservatively 1)
  (add-hook 'term-setup-hook (lambda () (goto-char (point-max))))

And /tmp/foo.cpp as attached.

Also set the keyboard repitition rate somewhat high.

Start Emacs by: emacs -Q /tmp/foo.cpp --load /tmp/scroll-conservatively-1.el

Hold arrow up key, recentering occurs while scrolling up.

Note: Script goes to EOB because I only witness this for scroll ups, not
scroll downs.

I witness this regularly when navigating C++ source code.

----

In GNU Emacs 24.3.50.6 (x86_64-unknown-linux-gnu, GTK+ Version 2.10.4)
 of 2013-05-23 on redacted
Windowing system distributor `The X.Org Foundation', version 11.0.70101000
System Description:    Red Hat Enterprise Linux Client release 5.4 (Tikanga)

Configured using:
 `configure --prefix=/redacted/user/boreilly/sw/emacs-install-trunk
 --with-gif=no'

Important settings:
  value of $LANG: en_US.UTF-8
  value of $XMODIFIERS: @im=none
  locale-coding-system: utf-8-unix
  default enable-multibyte-characters: t

Major mode: C++/l

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  font-lock-mode: t
  blink-cursor-mode: t
  auto-composition-mode: t
  auto-encryption-mode: t
  auto-compression-mode: t
  line-number-mode: t
  transient-mark-mode: t
  abbrev-mode: t

Recent input:
M-x r e p o r t - e m a c <tab> <return>

Recent messages:
For information about GNU Emacs and the GNU system, type C-h C-a.
foo.cpp has auto save data; consider M-x recover-this-file
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