bug#10947: 24.0.92; The variable `erc-channel-users' can be invalid after reconnection

[Deniz Dogan]

I noticed this when I disconnected the Internet cable from my machine
and then plugged it back in a while later to reconnect.  When I hit C-c
C-n to list the users, a bot of mine was listed among the users.  I did
/whois the_nickname and got "No such nick/channel".

After some investigation, I found that ERC doesn't clear
erc-channel-users when an unexpected disconnection occurs.  I've
attached a patch which addresses this problem.

=== modified file 'lisp/erc/ChangeLog'
--- lisp/erc/ChangeLog  2012-02-09 07:48:22 +0000
+++ lisp/erc/ChangeLog  2012-03-05 16:26:23 +0000
@@ -1,3 +1,9 @@
+2012-03-05  Deniz Dogan  <deniz@dogan.se>
+
+       * erc-backend.el (erc-process-sentinel): Clear channel user lists
+       upon disconnection.  This prevents invalid channel user lists when
+       reconnecting.
+
 2012-02-08  Glenn Morris  <rgm@gnu.org>

        * erc-backend.el (erc-coding-system-precedence):
@@ -277,4 +283,3 @@
 ;; coding: utf-8
 ;; add-log-time-zone-rule: t
 ;; End:
-

=== modified file 'lisp/erc/erc-backend.el'
--- lisp/erc/erc-backend.el     2012-02-08 08:07:24 +0000
+++ lisp/erc/erc-backend.el     2012-03-02 15:22:22 +0000
@@ -680,6 +680,9 @@
                    (setq erc-server-ping-handler nil)))
           (run-hook-with-args 'erc-disconnected-hook
                               (erc-current-nick) (system-name) "")
+          (dolist (buf (erc-buffer-filter (lambda () (boundp 
'erc-channel-users)) cproc))
+            (with-current-buffer buf
+              (setq erc-channel-users (make-hash-table :test 'equal))))
           ;; Remove the prompt
           (goto-char (or (marker-position erc-input-marker) (point-max)))
           (forward-line 0)



In GNU Emacs 24.0.92.1 (i386-mingw-nt6.1.7601)
 of 2012-01-17 on MARVIN
Windowing system distributor `Microsoft Corp.', version 6.1.7601
configured using `configure --with-gcc (4.6) --no-opt --cflags 
-ID:/devel/emacs/libs/libXpm-3.5.8/include 
-ID:/devel/emacs/libs/libXpm-3.5.8/src 
-ID:/devel/emacs/libs/libpng-dev_1.4.3-1/include 
-ID:/devel/emacs/libs/zlib-dev_1.2.5-2/include 
-ID:/devel/emacs/libs/giflib-4.1.4-1/include 
-ID:/devel/emacs/libs/jpeg-6b-4/include 
-ID:/devel/emacs/libs/tiff-3.8.2-1/include 
-ID:/devel/emacs/libs/gnutls-3.0.9/include --ldflags 
-LD:/devel/emacs/libs/gnutls-3.0.9/lib'

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: SVE
  value of $XMODIFIERS: nil
  locale-coding-system: cp1252
  default enable-multibyte-characters: t

Major mode: Help

Minor modes in effect:
  diff-auto-refine-mode: t
  erc-truncate-mode: t
  erc-services-mode: t
  erc-ring-mode: t
  erc-networks-mode: t
  erc-netsplit-mode: t
  erc-menu-mode: t
  erc-list-mode: t
  erc-pcomplete-mode: t
  erc-button-mode: t
  erc-fill-mode: t
  erc-stamp-mode: t
  erc-autojoin-mode: t
  popcmp-group-alternatives: t
  popcmp-short-help-beside-alts: t
  erc-track-mode: t
  erc-track-minor-mode: t
  erc-match-mode: t
  erc-irccontrols-mode: t
  erc-noncommands-mode: t
  erc-move-to-prompt-mode: t
  erc-readonly-mode: t
  erc-scrolltobottom-mode: t
  electric-indent-mode: t
  nxhtml-menu-mode: t
  rcirc-track-minor-mode: t
  tooltip-mode: t
  mouse-wheel-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
  size-indication-mode: t
  column-number-mode: t
  line-number-mode: t
  transient-mark-mode: t

Recent messages:
Wrote d:/repos/emacs/trunk/lisp/erc/ChangeLog
Finding changes in d:/repos/emacs/trunk/lisp/erc/...done
Mark set [2 times]
Quit
Saving file d:/erc-channel-users.patch...
Wrote d:/erc-channel-users.patch
Quit
Making completion list...
Type "q" in help window to restore its previous buffer.
Mark activated

Load-path shadows:
d:/repos/nxhtml/related/django hides ~/.emacs.d/django
d:/repos/nima/json hides c:/misc/emacs/lisp/json
d:/repos/nxhtml/util/org-odt hides c:/misc/emacs/lisp/org/org-odt

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