[PATCH] emacs: use the originating buffer's working directory for pipe

[Jani Nikula]

Currently notmuch-show-pipe-message runs the command in the working
directory of the *notmuch-pipe* buffer if it exists, and the current
buffer's working directory (which is inherited to the new
*notmuch-pipe* buffer) otherwise. This is all very surprising to the
user, and it's difficult to know or change where the command will be
run.

Always use the current show buffer's working directory for piping. The
user can check that with M-x pwd and change it with M-x cd. This is
consistent with notmuch-show-pipe-part.

---

Mark also suggested printing the working directory in the prompt for
the command to pipe to, but when I tried it I thought the prompt
became too crowded with that. It's also less important now that the
current buffer's working directory is used consistently.
---
 emacs/notmuch-show.el | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/emacs/notmuch-show.el b/emacs/notmuch-show.el
index 88752f171930..b8782ddb632e 100644
--- a/emacs/notmuch-show.el
+++ b/emacs/notmuch-show.el
@@ -1781,10 +1781,14 @@ message."
       (setq shell-command
 	    (concat notmuch-command " show --format=raw "
 		    (shell-quote-argument (notmuch-show-get-message-id)) " | " command)))
-    (let ((buf (get-buffer-create (concat "*notmuch-pipe*"))))
+    (let ((cwd default-directory)
+	  (buf (get-buffer-create (concat "*notmuch-pipe*"))))
       (with-current-buffer buf
 	(setq buffer-read-only nil)
 	(erase-buffer)
+	;; Use the originating buffer's working directory instead of
+	;; that of the pipe buffer.
+	(cd cwd)
 	(let ((exit-code (call-process-shell-command shell-command nil buf)))
 	  (goto-char (point-max))
 	  (set-buffer-modified-p nil)
-- 
1.8.5.3