bug#20284: 25.0.50; sexp parser breaks when 'vectors' are in docstring

[Tim Visher]

Starting from `emacs -Q`:

In *scratch* define the following function

(defun should-this-work? ()
  "A docstring with 'vectors'

[|[a b c]
  [d e f]
  [g h i]]

[[|a b c]
 [ d e f]
 [ g h i]]"
  (message "charnock"))

With point in the body, attempt to `M-x eval-defun` and notice that it
doesn't.

Attempt to add to the body and notice that indentation is off.

Other sexp things behave in unexpected ways.

Remove the vectors and everything goes back to normal.

(defun should-this-work? ()
  "A docstring with 'vectors'"
  (message "charnock"))



In GNU Emacs 25.0.50.1 (x86_64-apple-darwin14.1.0)
 of 2015-04-02 on timvisher-rjmetrics
Repository revision: 0c2ea36d2032ef47a0d6520b3e513459e072a553
Configured using:
 `configure --prefix=/usr/local/Cellar/emacs/HEAD
 --enable-locallisppath=/usr/local/share/emacs/site-lisp
 --infodir=/usr/local/Cellar/emacs/HEAD/share/info/emacs --without-dbus
 --with-gnutls --without-popmail --without-x'

Configured features:
ACL GNUTLS LIBXML2 ZLIB

Important settings:
  value of $LANG: en_US.UTF-8
  locale-coding-system: utf-8-unix

Major mode: Lisp Interaction

Minor modes in effect:
  tooltip-mode: t
  global-eldoc-mode: t
  electric-indent-mode: t
  menu-bar-mode: t
  file-name-shadow-mode: t
  global-font-lock-mode: t
  font-lock-mode: t
  auto-composition-mode: t
  auto-encryption-mode: t
  auto-compression-mode: t
  line-number-mode: t

Recent messages:
For information about GNU Emacs and the GNU system, type C-h C-a.
Undo!
should-this-work\?
Quit
[[|a b c] [d e f] [g h i]]

Load-path shadows:
None found.

Features:
(shadow sort gnus-util mail-extr emacsbug message dired format-spec
rfc822 mml easymenu mml-sec mm-decode mm-bodies mm-encode mail-parse
rfc2231 mailabbrev gmm-utils mailheader sendmail regexp-opt rfc2047
rfc2045 ietf-drums mm-util help-fns mail-prsvr mail-utils xterm
time-date tooltip eldoc electric uniquify ediff-hook vc-hooks
lisp-float-type tabulated-list newcomment elisp-mode lisp-mode prog-mode
register page menu-bar rfn-eshadow timer select 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
cl-preloaded nadvice loaddefs button faces cus-face macroexp files
text-properties overlay sha1 md5 base64 format env code-pages mule
custom widget hashtable-print-readable backquote make-network-process
multi-tty emacs)

Memory information:
((conses 16 78118 4713)
 (symbols 48 17307 0)
 (miscs 40 33 102)
 (strings 32 11188 4994)
 (string-bytes 1 302658)
 (vectors 16 7635)
 (vector-slots 8 339885 30258)
 (floats 8 75 612)
 (intervals 56 203 51)
 (buffers 976 11))