bug#12141: 24.1.50; Mismatched parentheses in Python mode. Regression between 2012-07-14 and 2012-07-28.

[Matt McClure]

This bug report will be sent to the Bug-GNU-Emacs mailing list
and the GNU bug tracker at debbugs.gnu.org.  Please check that
the From: line contains a valid email address.  After a delay of up
to one day, you should receive an acknowledgment at that address.

Please write in English if possible, as the Emacs maintainers
usually do not have translators for other languages.

Please describe exactly what actions triggered the bug, and
the precise symptoms of the bug.  If you can, give a recipe
starting from `emacs -Q':

Between 2012-07-14 and 2012-07-28, Emacs regressed and started reporting
"Mismatched parentheses" in Python buffers where the parentheses are
matched.

To reproduce on Mac OS X:

    open -a Emacs --args -Q --no-site-file

    C-x C-f foo.py

    def foo()

Observe on typing `)` that the echo area reports "Mismatched parentheses".

Expected: the cursor flashes briefly on the matching opening `(`.

The defect is present in:

GNU Emacs 24.1.50.1 (x86_64-apple-darwin, NS apple-appkit-1038.36) of
2012-07-28 on bob.porkrind.org

And is not reproducible in:

GNU Emacs 24.1.50.1 (x86_64-apple-darwin, NS apple-appkit-1038.36) of
2012-07-14 on bob.porkrind.org

If Emacs crashed, and you have the Emacs process in the gdb debugger,
please include the output from the following gdb commands:
    `bt full' and `xbacktrace'.
For information about debugging Emacs, please read the file
/Applications/Emacs.app/Contents/Resources/etc/DEBUG.


In GNU Emacs 24.1.50.1 (x86_64-apple-darwin, NS apple-appkit-1038.36)
 of 2012-07-28 on bob.porkrind.org
Bzr revision: 109240 eggert@cs.ucla.edu-20120727205002-le47yl02ika3h8ys
Windowing system distributor `Apple', version 10.3.1138
Configured using:
 `configure '--host=x86_64-apple-darwin' '--build=i686-apple-darwin'
 '--with-ns' 'build_alias=i686-apple-darwin'
 'host_alias=x86_64-apple-darwin' 'CC=gcc -mmacosx-version-min=10.5''

Important settings:
  value of $LANG: en_US.UTF-8
  locale-coding-system: utf-8-unix
  default enable-multibyte-characters: t

Major mode: Python

Minor modes in effect:
  tooltip-mode: t
  mouse-wheel-mode: t
  tool-bar-mode: t
  menu-bar-mode: t
  file-name-shadow-mode: t
  global-font-lock-mode: t
  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

Recent input:
C-x C-f ~ / D o w n l o a d s / f o o . p y <return>
d e f SPC f o o ( ) <escape> x r e m p o <tab> <backspace>
<backspace> <backspace> p o <tab> r <tab> <return>
M i s m a t c h e d SPC p a r a <backspace> e n C-x
o C-x b C-g C-g C-g C-x o C-x b * M e <tab> <return>
C-p C-p C-p C-p C-p C-p C-p C-n C-n C-a C-s m i s m
a C-a C-x b <return> <backspace> ) <escape> x r e p
o r t SPC e m <tab> <return>

Recent messages:
For information about GNU Emacs and the GNU system, type C-h C-a.
Can't guess python-indent-offset, using defaults: 4
Making completion list...
byte-code: Command attempted to use minibuffer while in minibuffer
Quit [3 times]
byte-code: Beginning of buffer [2 times]
Mark saved where search started

Load-path shadows:
None found.

Features:
(shadow sort gnus-util mail-extr misearch multi-isearch emacsbug message
format-spec rfc822 mml mml-sec mm-decode mm-bodies mm-encode mail-parse
rfc2231 mailabbrev gmm-utils mailheader sendmail rfc2047 rfc2045
ietf-drums mm-util mail-prsvr mail-utils help-mode python rx easymenu
comint ring ansi-color time-date tooltip ediff-hook vc-hooks
lisp-float-type mwheel ns-win tool-bar dnd fontset image regexp-opt
fringe tabulated-list newcomment lisp-mode register page menu-bar
rfn-eshadow timer select scroll-bar mouse jit-lock font-lock syntax
facemenu font-core frame cham georgian utf-8-lang misc-lang vietnamese
tibetan thai tai-viet lao korean japanese hebrew greek romanian slovak
czech european ethiopic indian cyrillic chinese case-table epa-hook
jka-cmpr-hook help simple abbrev minibuffer loaddefs button faces
cus-face files text-properties overlay sha1 md5 base64 format env
code-pages mule custom widget hashtable-print-readable backquote
make-network-process ns multi-tty emacs)

--
Matt McClure
http://www.matthewlmcclure.com
http://www.mapmyfitness.com/profile/matthewlmcclure