bug#20579: 24.4; Pong bat loses 1/3rd of its length if the ball hits it too quickly

[Matt Lee <mattl@creativecommons.org>]

* Start Emacs and start pong

* Immediately move the left bat down a square or two

* As the ball is about to miss your bat, move up quickly so your bat
essentially overrwrites the space of the ball on screen

* The ball bounces, but your bat is left as two, not three squares long.



In GNU Emacs 24.4.1 (x86_64-pc-linux-gnu, GTK+ Version 3.14.5)
of 2015-03-07 on trouble, modified by Debian
Windowing system distributor `The X.Org Foundation', version 11.0.11604000
System Description: Debian GNU/Linux 8.0 (jessie)

Configured using:
`configure --build x86_64-linux-gnu --prefix=/usr
--sharedstatedir=/var/lib --libexecdir=/usr/lib
--localstatedir=/var/lib --infodir=/usr/share/info
--mandir=/usr/share/man --with-pop=yes
--enable-locallisppath=/etc/emacs24:/etc/emacs:/usr/local/share/emacs/24.4/site-lisp:/usr/local/share/emacs/site-lisp:/usr/share/emacs/24.4/site-lisp:/usr/share/emacs/site-lisp 

--build x86_64-linux-gnu --prefix=/usr --sharedstatedir=/var/lib
--libexecdir=/usr/lib --localstatedir=/var/lib
--infodir=/usr/share/info --mandir=/usr/share/man --with-pop=yes
--enable-locallisppath=/etc/emacs24:/etc/emacs:/usr/local/share/emacs/24.4/site-lisp:/usr/local/share/emacs/site-lisp:/usr/share/emacs/24.4/site-lisp:/usr/share/emacs/site-lisp 

--with-x=yes --with-x-toolkit=gtk3 --with-toolkit-scroll-bars
'CFLAGS=-g -O2 -fstack-protector-strong -Wformat
-Werror=format-security -Wall' CPPFLAGS=-D_FORTIFY_SOURCE=2
LDFLAGS=-Wl,-z,relro'

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

Major mode: Info

Minor modes in effect:
tooltip-mode: t
electric-indent-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
buffer-read-only: t
line-number-mode: t
transient-mark-mode: t

Recent input:
M-x p o n g <return> <left> <right> <left> <left> <left>
<left> <left> <right> <right> <right> <right> <right>
<right> <right> <help-echo> <right> <left> <left> <left>
<up> <up> <down> <down> <down> <down> <down> <down>
<up> <left> <right> <down> <up> <up> <left> <left>
<left> <left> <left> <left> <left> <left> <left> <left>
<left> <left> <right> <right> <up> <up> <up> <up> <up>
<up> <down> <up> <up> <up> <down> <down> <down> <down>
<down> <up> <right> <right> <right> <right> <right>
<right> <right> <right> <right> <left> <left> <left>
<left> <left> <left> <left> <right> <left> <down> <right>
<right> <left> <down> <up> <up> <down> <left> <right>
<right> <left> <down> <down> <down> <down> <down> <down>
<down> <down> <right> <right> <right> <right> <right>
<right> <right> <right> <right> <right> <right> <left>
<right> <left> <right> <left> <help-echo> <help-echo>
<help-echo> <help-echo> <help-echo> <help-echo> <help-echo>
<menu-bar> <help-menu> <emacs-manual-bug> <help-echo>
<help-echo> <help-echo> <help-echo> <help-echo> <help-echo>
<help-echo> <menu-bar> <help-menu> <send-emacs-bug
-report>

Recent messages:
call-interactively: Buffer is read-only: #<buffer *Pong*> [5 times]
Quit
call-interactively: Buffer is read-only: #<buffer *Pong*>
command-execute: Buffer is read-only: #<buffer *Pong*>
ESC ESC <menu-bar> is undefined
<tools> is undefined
<games> is undefined
<pong> is undefined
Error running timer `kill-buffer': (error "No buffer named *Pong*")
Composing main Info directory...done
user-error: Info file emacs does not exist

Load-path shadows:
/usr/share/emacs/24.4/site-lisp/debian-startup hides 
/usr/share/emacs/site-lisp/debian-startup
/usr/share/emacs24/site-lisp/cmake-data/cmake-mode hides 
/usr/share/emacs/site-lisp/cmake-mode
/usr/share/emacs24/site-lisp/dictionaries-common/ispell hides 
/usr/share/emacs/24.4/lisp/textmodes/ispell
/usr/share/emacs24/site-lisp/dictionaries-common/flyspell hides 
/usr/share/emacs/24.4/lisp/textmodes/flyspell

Features:
(shadow sort gnus-util mail-extr 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
help-fns mail-prsvr mail-utils info easymenu disp-table pong gamegrid
markdown-mode-autoloads multiple-cursors-autoloads php-mode-autoloads
web-mode-autoloads zenburn-theme-autoloads package epg-config time-date
tooltip electric uniquify ediff-hook vc-hooks lisp-float-type mwheel
x-win x-dnd tool-bar dnd fontset image regexp-opt fringe tabulated-list
newcomment lisp-mode prog-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 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
dbusbind gfilenotify dynamic-setting system-font-setting
font-render-setting move-toolbar gtk x-toolkit x multi-tty emacs)

Memory information:
((conses 16 118206 6010)
(symbols 48 20574 0)
(miscs 40 88 185)
(strings 32 21586 4423)
(string-bytes 1 540426)
(vectors 16 12016)
(vector-slots 8 418703 5823)
(floats 8 80 419)
(intervals 56 3093 0)
(buffers 960 14)
(heap 1024 52752 1029))

-- 
Matt Lee
Technical Lead, Creative Commons, Boston, MA
https://keybase.io/mattl

"Creativity can be a social contribution, but only in
so far as society is free to use the results." -- Stallman