emacs: Tell `message-mode' that outgoing messages are email.

When composing messages (including replies, etc.), indicate to
`message-mode' definitively that the message is email (as opposed to
Usenet news) rather than having it attempt to determine this for itself.

This causes `message-mode' to observe such variables as
`message-default-mail-headers', which previously happened haphazardly.

diff --git a/emacs/notmuch-mua.el b/emacs/notmuch-mua.el
index 04459750073c582370d87fa3b743d22dad972e5f..399e1380df02a8ac2d0caae38179ad675135866f 100644 (file)
--- a/emacs/notmuch-mua.el
+++ b/emacs/notmuch-mua.el
@@ -338,7 +338,10 @@ modified. This function is notmuch addaptation of
          ;; We need to convert any string input, eg from rmail-start-mail.
          (dolist (h other-headers other-headers)
            (if (stringp (car h)) (setcar h (intern (capitalize (car h))))))))
-       (args (list yank-action send-actions)))
+       (args (list yank-action send-actions))
+       ;; Cause `message-setup-1' to do things relevant for mail,
+       ;; such as observe `message-default-mail-headers'.
+       (message-this-is-mail t))
     ;; message-setup-1 in Emacs 23 does not accept return-action
     ;; argument. Pass it only if it is supplied by the caller. This
     ;; will never be the case when we're called by `compose-mail' in