bug#12340: 24.2.50; python-shell-switch-to-shell in TRAMP buffer gives "No such file or directory: '/var/folders/vk/p95wm1qx0vdf0087p0z9qzc40000gn/T/py62333GTT'"

[Matt McClure]

This bug report will be sent to the Bug-GNU-Emacs mailing list
and the GNU bug tracker at debbugs.gnu.org.  Please check that
the From: line contains a valid email address.  After a delay of up
to one day, you should receive an acknowledgment at that address.

Please write in English if possible, as the Emacs maintainers
usually do not have translators for other languages.

Please describe exactly what actions triggered the bug, and
the precise symptoms of the bug.  If you can, give a recipe
starting from `emacs -Q':

***

To reproduce:

    $ open -n -a Emacs --args -Q --no-site-file --eval '(progn
(find-file "/<user>@<host>:~/<foo>.py")
(python-shell-switch-to-shell))'

    RET n (or y)

The *Python* buffer contains:

    Python 2.4.3 (#1, Jun 18 2012, 08:55:23)
    [GCC 4.1.2 20080704 (Red Hat 4.1.2-52)] on linux2
    Type "help", "copyright", "credits" or "license" for more information.
    >>> Traceback (most recent call last):
      File "<stdin>", line 1, in ?
    IOError: [Errno 2] No such file or directory:
'/var/folders/vk/p95wm1qx0vdf0087p0z9qzc40000gn/T/py62333GTT'
    >>> Traceback (most recent call last):
      File "<stdin>", line 1, in ?
    IOError: [Errno 2] No such file or directory:
'/var/folders/vk/p95wm1qx0vdf0087p0z9qzc40000gn/T/py62333TdZ'
    >>> Traceback (most recent call last):
      File "<stdin>", line 1, in ?
    IOError: [Errno 2] No such file or directory:
'/var/folders/vk/p95wm1qx0vdf0087p0z9qzc40000gn/T/py62333gnf'
    >>>

Looks to me as though python.el and TRAMP need to use the temporary
directory on the remote machine rather than the local machine.

I'm able to reproduce the defect in
Emacs-2012-07-14-109087-universal-10.6.8 at least through
Emacs-2012-08-28-109798-universal-10.6.8 but not in
Emacs-2012-06-08-108519-universal-10.6.8. In
Emacs-2012-06-08-108519-universal-10.6.8 the equivalent recipe to get
to a Python shell is:

    open -n -a Emacs --args -Q --no-site-file --eval '(progn
(find-file "/vagrant@192.168.33.2:~/hello.py")
(python-switch-to-python nil))'

***

If Emacs crashed, and you have the Emacs process in the gdb debugger,
please include the output from the following gdb commands:
    `bt full' and `xbacktrace'.
For information about debugging Emacs, please read the file
/Applications/Emacs.app/Contents/Resources/etc/DEBUG.


In GNU Emacs 24.2.50.1 (x86_64-apple-darwin, NS apple-appkit-1038.36)
 of 2012-08-28 on bob.porkrind.org
Bzr revision: 109798 dmantipov@yandex.ru-20120828062008-t2jfhu5niq9upru9
Windowing system distributor `Apple', version 10.3.1138
Configured using:
 `configure '--host=x86_64-apple-darwin' '--build=i686-apple-darwin'
 '--with-ns' 'build_alias=i686-apple-darwin'
 'host_alias=x86_64-apple-darwin' 'CC=gcc -mmacosx-version-min=10.5''

Important settings:
  value of $LANG: en_US.UTF-8
  locale-coding-system: utf-8-unix
  default enable-multibyte-characters: t

Major mode: Inferior Python

Minor modes in effect:
  compilation-shell-minor-mode: t
  shell-dirtrack-mode: t
  tooltip-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
  line-number-mode: t
  transient-mark-mode: t

Recent input:
<return> n C-x h <escape> w <escape> x r e p o r t
<tab> <return>

Recent messages:

Tramp: Waiting for prompts from remote shell
Tramp: Sending command `exec ssh -q -l vagrant  -o
ControlPath=/var/folders/vk/p95wm1qx0vdf0087p0z9qzc40000gn/T/tramp.623335IN.%r@%h:%p
-o ControlMaster=yes -e none 192.168.33.2'
Tramp: Found remote shell prompt on `192.168.33.2'
Tramp: Opening connection for vagrant@192.168.33.2 using scpc...done
Sent python-shell-completion-setup-code
Sent python-ffap-setup-code
Sent python-eldoc-setup-code
Mark set [2 times]
delete-backward-char: Text is read-only

Load-path shadows:
None found.

Features:
(shadow sort mail-extr misearch multi-isearch emacsbug message rfc822
mml mml-sec mm-decode mm-bodies mm-encode mail-parse rfc2231 mailabbrev
gmm-utils mailheader sendmail rfc2047 rfc2045 ietf-drums mail-utils
compile python rx easymenu tramp-cache tramp-sh tramp tramp-compat
auth-source eieio byte-opt bytecomp byte-compile cconv macroexp
gnus-util mm-util mail-prsvr password-cache tramp-loaddefs shell
pcomplete comint ansi-color ring format-spec advice help-fns
advice-preload time-date tooltip ediff-hook vc-hooks lisp-float-type
mwheel ns-win tool-bar dnd fontset image regexp-opt fringe
tabulated-list newcomment lisp-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 loaddefs button faces
cus-face files text-properties overlay sha1 md5 base64 format env
code-pages mule custom widget hashtable-print-readable backquote
make-network-process ns multi-tty emacs)


-- 
Matt McClure
http://www.matthewlmcclure.com
http://www.mapmyfitness.com/profile/matthewlmcclure