Re: Error with function gnus-summary-pipe-output (Was htmlified mail)

["James H. Cloos Jr." <cloos@jhcloos.com>]

>>>>> "ZSH" == ShengHuo ZHU <zsh@cs.rochester.edu> writes:

ZSH> gnus-default-article-saver is bound to gnus-summary-save-in-pipe
ZSH> when trying `|'.  If Gnus changes the value after the command, it
ZSH> is because there was a bug in Gnus 5.8.7 and previous versions.
ZSH> A workaround is putting (require 'gnus-art) in ~/.gnus .

This has no effect on getting | to work.  I still get 'default as the
last argument in the call to call-process-region.

The code (as of 5.8.8) looks like:

(defun gnus-summary-save-in-pipe (&optional command)
  "Pipe this article to subprocess."
  (setq command
	(cond ((and (eq command 'default)
		    gnus-last-shell-command)
	       gnus-last-shell-command)
	      (command command)
	      (t (read-string
		  (format
		   "Shell command on %s: "
		   (if (and gnus-number-of-articles-to-be-saved
			    (> gnus-number-of-articles-to-be-saved 1))
		       (format "these %d articles"
			       gnus-number-of-articles-to-be-saved)
		     "this article"))
		  gnus-last-shell-command))))
  (when (string-equal command "")
    (setq command gnus-last-shell-command))
  (gnus-eval-in-buffer-window gnus-article-buffer
    (save-restriction
      (widen)
      (shell-command-on-region (point-min) (point-max) command nil)))
  (setq gnus-last-shell-command command))


That 'default up there appears to get sent to shell-command-on-region.
Note that read-string is NOT called when the error occurs.  Note that
default is not AFAICT defined.  Anf this bug has existed in every
version of ding that I have tried.  (I had to think about when I was
first hit with it for a while; it was indeed when I discovered ding
and upgraded from whatever version/capitalization of gnus I'd been using.

So.  (eq command 'default) is presumably nil.  gnus-last-shell-command
as well, so command is not setq to (gnus-last-shell-command).  command
is not set AFAICT, so command is not setq to the old value of command
either.  So read-string ought to be run.  But it is not.

Just tested by manually calling (gnus-summary-save-in-pipe "ls").
The backtrace is now:

Signaling: (wrong-type-argument stringp default)
  call-process-region(1 902 "/bin/bash" "/tmp/emacseha4Xw"
            #<buffer *Shell Command Output*> nil "-c" default)
  shell-command-on-region(1 902 default nil)
  gnus-summary-save-in-pipe(default)
  byte-code("**ELIDED**" [gnus-default-article-saver gnus-article-buffer
            save-buffer gnus-save-article-buffer gnus-prompt-before-saving
            file error "No default saver is defined" default always nil t
            filename num gnus-number-of-articles-to-be-saved
            gnus-article-current-summary] 2)
  gnus-article-save(#<buffer  *Gnus Save*> nil 1)
  gnus-summary-save-article(nil t)
  gnus-summary-pipe-output(nil)
  call-interactively(gnus-summary-pipe-output)
  gnus-article-read-summary-keys(nil)
* call-interactively(gnus-article-read-summary-keys)

as you can see, gnus-summary-save-in-pipe is still called with the arg default.
The bytecode shows that gnus-article-save's fragment:

     (if (not gnus-default-article-saver)
        (error "No default saver is defined")

indicates that (not gnus-default-article-saver) is returning t.  The
variable is now set to gnus-summary-save-in-rmail (since I removed
the reference to it in ~/.emacs.el).  Running a (setq gnus-default-
article-saver 'gnus-summary-save-in-file) does not change the backtrace.

-JimC
-- 
James H. Cloos, Jr.  <http://jhcloos.com/public_key>     1024D/ED7DAEA6 
<cloos@jhcloos.com>  E9E9 F828 61A4 6EA9 0F2B  63E7 997A 9F17 ED7D AEA6