bug#21867: 25.0.50; lossage's log doesn't treat characters read by read-char as separate commands

[Zachary Kanfer]

The way that lossage now shows different commands on different lines is
really useful, but I found a way where it's not treating two different
things as different commands. To reproduce:

emacs -Q

open the scratch buffer

insert this whole s-_expression_:

(read-char)

Then, with point at the end of that line, type:

C-x C-e a C-h l

This evaluates the (read-char) sexp which reads the `a` typed, then
views lossage.

The last lines of lossage are:

 C-x C-e [eval-last-sexp]
 a C-h l [view-lossage]

Note that the log line calling view-lossage also includes "a", the
command read by read-char. I would expect the lossage buffer to be
something like this:

 C-x C-e [eval-last-sexp]
 a [char read by read-char]
 C-h l [view-lossage]

This does not happen with read-string; one gets logs like:

 C-x C-e [eval-last-sexp]
 p [self-insert-command]
 a [self-insert-command]
 n [self-insert-command]
 t [self-insert-command]
 s [self-insert-command]
 <return> [exit-minibuffer]
 C-h l [view-lossage]

I noted this when viewing lossage after calling org-agenda, which I
think uses read-char to get a character to dispatch on. However, I'm not
sure; the package is too complicated for me to track down how it's
reading the character. The same behavior happens when calling read-char,
so it might be the same thing.


In GNU Emacs 25.0.50.9 (x86_64-unknown-linux-gnu, GTK+ Version 3.10.8)
 of 2015-10-31
Repository revision: e4740877d6feeb357d7437e6025dba641800c11d
Windowing system distributor 'The X.Org Foundation', version 11.0.11501000
System Description:    Ubuntu 14.04.3 LTS

Configured features:
XPM JPEG TIFF GIF PNG SOUND GSETTINGS NOTIFY GNUTLS LIBXML2 FREETYPE XFT
ZLIB TOOLKIT_SCROLL_BARS GTK3 X11

Important settings:
  value of $LANG: en_US.UTF-8
  value of $XMODIFIERS: @im=ibus
  locale-coding-system: utf-8-unix

Major mode: Help

Minor modes in effect:
  tooltip-mode: t
  global-eldoc-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 messages:
C-h j is undefined
Rebuilding agenda buffer...done
Log mode is on
Type "q" in help window to restore its previous buffer.
C-, is undefined
Press key for agenda command:
C-c l is undefined
Press key for agenda command:

C-, is undefined

Load-path shadows:
None found.

Features:
(shadow sort gnus-util mail-extr emacsbug message dired 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 help-mode cal-iso org-agenda org
org-macro org-footnote org-pcomplete pcomplete org-list org-faces
org-entities noutline outline easy-mmode org-version ob-emacs-lisp ob
ob-tangle ob-ref ob-lob ob-table ob-exp org-src ob-keys ob-comint comint
ansi-color ring ob-core ob-eval org-compat org-macs org-loaddefs
format-spec find-func cal-menu easymenu calendar cal-loaddefs edmacro
kmacro cl-loaddefs pcase cl-lib time-date mule-util tooltip eldoc
electric uniquify ediff-hook vc-hooks lisp-float-type mwheel x-win
term/common-win x-dnd tool-bar dnd fontset image regexp-opt fringe
tabulated-list newcomment elisp-mode lisp-mode prog-mode register page
menu-bar rfn-eshadow timer select scroll-bar mouse jit-lock font-lock
syntax facemenu font-core frame cl-generic cham georgian utf-8-lang
misc-lang vietnamese tibetan thai tai-viet lao korean japanese eucjp-ms
cp51932 hebrew greek romanian slovak czech european ethiopic indian
cyrillic chinese charscript 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
inotify dynamic-setting system-font-setting font-render-setting
move-toolbar gtk x-toolkit x multi-tty make-network-process emacs)

Memory information:
((conses 16 133879 6850)
 (symbols 48 25562 0)
 (miscs 40 489 115)
 (strings 32 32608 5367)
 (string-bytes 1 1089148)
 (vectors 16 16809)
 (vector-slots 8 483236 6626)
 (floats 8 171 440)
 (intervals 56 364 3)
 (buffers 976 14)
 (heap 1024 35202 1287))