bug#4891: 23.1; shell-command overwrites whole buffer

[Adam Spiers <bug-gnu-emacs@adamspiers.org>]

Starting emacs 23.1.1 with the '-q' argument and typing:

  M-: (shell-command "date" (get-buffer "*scratch*"))

results in the prior contents of the *scratch* buffer being
overwritten.  This seems to contradict the last sentence in the
following paragraph of the docstring for shell-command:

    The optional second argument output-buffer, if non-nil, says to
    put the output in some other buffer.  If output-buffer is a buffer
    or buffer name, put the output there.  If output-buffer is not a
    buffer and not nil, insert output in current buffer.  (This cannot
    be done asynchronously.)  In either case, the output is inserted
    after point (leaving mark after it).

In GNU Emacs 23.1.1 (i386-redhat-linux-gnu, GTK+ Version 2.16.6)
 of 2009-09-29 on x86-7.fedora.phx.redhat.com
Windowing system distributor `The X.Org Foundation', version 11.0.10603901
configured using `configure  '--build=i386-redhat-linux-gnu' '--host=i386-redhat-linux-gnu' '--target=i586-redhat-linux-gnu' '--program-prefix=' '--prefix=/usr' '--exec-prefix=/usr' '--bindir=/usr/bin' '--sbindir=/usr/sbin' '--sysconfdir=/etc' '--datadir=/usr/share' '--includedir=/usr/include' '--libdir=/usr/lib' '--libexecdir=/usr/libexec' '--localstatedir=/var' '--sharedstatedir=/var/lib' '--mandir=/usr/share/man' '--infodir=/usr/share/info' '--with-dbus' '--with-gif' '--with-jpeg' '--with-png' '--with-rsvg' '--with-tiff' '--with-xft' '--with-xpm' '--with-x-toolkit=gtk' 'build_alias=i386-redhat-linux-gnu' 'host_alias=i386-redhat-linux-gnu' 'target_alias=i586-redhat-linux-gnu' 'CFLAGS=-DMAIL_USE_LOCKF -O2 -g -pipe -Wall -Wp,-D_FORTIFY_SOURCE=2 -fexceptions -fstack-protector --param=ssp-bu
 ffer-size=4 -m32 -march=i586 -mtune=generic -fasynchronous-unwind-tables''

Important settings:
  value of $LC_ALL: nil
  value of $LC_COLLATE: nil
  value of $LC_CTYPE: nil
  value of $LC_MESSAGES: nil
  value of $LC_MONETARY: nil
  value of $LC_NUMERIC: nil
  value of $LC_TIME: nil
  value of $LANG: en_GB.utf8
  value of $XMODIFIERS: nil
  locale-coding-system: utf-8-unix
  default-enable-multibyte-characters: t

Major mode: Lisp Interaction

Minor modes in effect:
  tooltip-mode: t
  mouse-wheel-mode: t
  menu-bar-mode: t
  file-name-shadow-mode: t
  global-font-lock-mode: t
  font-lock-mode: t
  blink-cursor-mode: t
  global-auto-composition-mode: t
  auto-composition-mode: t
  auto-encryption-mode: t
  auto-compression-mode: t
  line-number-mode: t
  transient-mark-mode: t

Recent input:
M-: ( s h e l l - c o m m a n d SPC " d a t e " S-SPC 
( g e t - b u f f e r SPC " * s c r a t c h * " ) ) 
<return> C-x b <return> M-x r e p o r <tab> 
<return>

Recent messages:
Loading /usr/share/emacs/site-lisp/site-start.d/muse-init.el (source)...done
Loading /usr/share/emacs/site-lisp/site-start.d/php-mode-init.el (source)...done
Loading /usr/share/emacs/site-lisp/site-start.d/po-mode-init.el (source)...done
Loading /usr/share/emacs/site-lisp/site-start.d/rpm-spec-mode-init.el (source)...done
Loading /usr/share/emacs/site-lisp/site-start.d/rpmdev-init.el (source)...done
Loading /usr/share/emacs/site-lisp/site-start.d/ruby-mode-init.el (source)...done
For information about GNU Emacs and the GNU system, type C-h C-a.
Mon Nov  9 10:38:11 GMT 2009
0 (#o0, #x0)
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