bug#4525: 23.1; RMAIL file carbon copy bug

[Lane A. Hemaspaandra]

Ever since we switched to Emacs 23 here, RMAIL has problems when
trying to reply (via rmail-summary-reply-to-sender-only, so I am in a
summary buffer, but the same happens if one is not in summary and is
on the message itself and types reply) to an email that itself was
written by "FCC" (file-carbon-copy).  The behavior is repeatable and
the same each time.  One hits the key that means reply, and emacs beeps
and the error line says:

Wrong type argument: char-or-string-p, nil

and then one is in a mail-message-creation buffer but the special
separator line between the header and the rest of the message is NOT
on a line by itself but comes right after "References: " and on the
same line as that "References: ".  I'm not wise in the ways of emacs,
but my guess is that things that are written to mailfiles via the FCC
path don't have enough "Reference" information to when replying to
them fill in the reference line in the standard way (in fact, looking
at the messages being replied to, they in the mbox-format mailfile
don't even HAVE any References line or any ID info or so on), and that
some routine that tries to do this somehow chokes.  This behavior
happens to me both on messages I FCC'ed to myself under emacs 23 and
also under messages I FCC'ed to myself long before emacs 23.  (So I've
now turned off FCC, but still I have this happen, namely, when I reply
to an old message.)

That this behavior has to do with "References:" generation is
suggested also by the fact that when I reply to FCC'ed-to-me-by-me
messages that DO have themselves a Reference line (because I was
myself replying in that to some email), this problem does not happen.

It happens whether the mailfile is in babyl or whether the mailfile
has been converted to mbox.  for example, here is what the start of an
mbox message is that has this problem when i try to reply to it.

If I turn on debug-on-error, and have this error, here is what I get
in the Backtrace window:

Debugger entered--Lisp error: (wrong-type-argument char-or-string-p nil)
  sendmail-user-agent-compose("\"Lane A. Hemaspaandra\" 
<lane@cs.rochester.edu>" "Re: critical room reservation: Theory Canal Seminar, 
room CSB 703" (("in-reply-to" . "\"lane@cs.rochester.edu\"'s message of 19 Jul 
2009 11:33:26 -0400") ("cc") ("References")) nil switch-to-buffer-other-window 
(insert-buffer #<buffer junknew>) ((rmail-mark-message #<buffer junknew> (117) 
0)))
  compose-mail("\"Lane A. Hemaspaandra\" <lane@cs.rochester.edu>" "Re: critical 
room reservation: Theory Canal Seminar, room CSB 703" (("in-reply-to" . 
"\"lane@cs.rochester.edu\"'s message of 19 Jul 2009 11:33:26 -0400") ("cc") 
("References")) nil switch-to-buffer-other-window (insert-buffer #<buffer 
junknew>) ((rmail-mark-message #<buffer junknew> (117) 0)))
  rmail-start-mail(nil "\"Lane A. Hemaspaandra\" <lane@cs.rochester.edu>" "Re: 
critical room reservation: Theory Canal Seminar, room CSB 703" 
"\"lane@cs.rochester.edu\"'s message of 19 Jul 2009 11:33:26 -0400" nil 
#<buffer junknew> ((rmail-mark-message #<buffer junknew> (117) 0)) nil 
(("References")))
  rmail-reply(t)
  rmail-summary-reply(t)
  rmail-summary-reply-to-sender-only()
  call-interactively(rmail-summary-reply-to-sender-only nil nil)

I can easily send a sample file that generates this behavior.  Thank
you very, very much.


In GNU Emacs 23.1.1 (i386-redhat-linux-gnu, GTK+ Version 2.16.5)
 of 2009-08-26 on x86-2.fedora.phx.redhat.com
configured using `configure  '--build=i386-redhat-linux-gnu' 
'--host=i386-redhat-linux-gnu' '--target=i586-redhat-linux-gnu' 
'--program-prefix=' '--prefix=/usr' '--exec-prefix=/usr' '--bindir=/usr/bin' 
'--sbindir=/usr/sbin' '--sysconfdir=/etc' '--datadir=/usr/share' 
'--includedir=/usr/include' '--libdir=/usr/lib' '--libexecdir=/usr/libexec' 
'--localstatedir=/var' '--sharedstatedir=/var/lib' '--mandir=/usr/share/man' 
'--infodir=/usr/share/info' '--with-dbus' '--with-gif' '--with-jpeg' 
'--with-png' '--with-rsvg' '--with-tiff' '--with-xft' '--with-xpm' 
'--with-x-toolkit=gtk' 'build_alias=i386-redhat-linux-gnu' 
'host_alias=i386-redhat-linux-gnu' 'target_alias=i586-redhat-linux-gnu' 
'CFLAGS=-DMAIL_USE_LOCKF -O2 -g -pipe -Wall -Wp,-D_FORTIFY_SOURCE=2 
-fexceptions -fstack-protector --param=ssp-buffer-size=4 -m32 -march=i586 
-mtune=generic -fasynchronous-unwind-tables''

Important settings:
  value of $LC_ALL: nil
  value of $LC_COLLATE: C
  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: en_US.UTF-8
  value of $XMODIFIERS: nil
  locale-coding-system: utf-8-unix
  default-enable-multibyte-characters: t

Major mode: Mail

Minor modes in effect:
  flyspell-mode: t
  shell-dirtrack-mode: t
  file-name-shadow-mode: t
  global-font-lock-mode: t
  font-lock-mode: t
  global-auto-composition-mode: t
  auto-composition-mode: t
  auto-encryption-mode: t
  auto-compression-mode: t
  line-number-mode: t
  transient-mark-mode: t

Recent input:
ESC [ > 0 ; 2 4 2 ; 0 c C-x r p a t r SPC RET p p p 
p p p p p p p q C-x r = s h SPC p a t r SPC RET p d 
y e s RET u q C-x r p a t r i SPC C-g C-g C-x r = s 
h SPC p a t r SPC RET d u p p p p p p p p p r ESC x 
r e p o r t - e m a c s - b u g RET

Recent messages:
Replacing BABYL format with mbox format...done
Computing summary lines...done
After this, patriciam<2> would be saved in mbox format.  Proceed? 
Saving file /u/lane/=shortCutToOldEmail/patriciam...
Wrote /u/lane/=shortCutToOldEmail/patriciam
Quit [2 times]
Computing summary lines...done
Starting new Ispell process [default] ...
compose-mail: Wrong type argument: char-or-string-p, nil
Auto-saving...