How supress a specific message from image/image+?

Question

When I open an image in Emacs, there is a message constantly showing in the minibuffer: "Type C-c C-c to view the image as text." which I cleary don't want.

When switching between images, the message is constanting asking for my attention, which bothers me. So I need to figure out how I could supress this message only. I tried alternatives like

(let ((inhibit-message t))
(message "Type C-c C-c to view the image as text."))

Or message-surpression.el, without any result at all. The message is still popping in my minibuffer when I open an image, and I couldn't figure out which function is calling that message.

Answer 1

The function in question is image-mode, and this seems to do what you want (if a little inelegantly):

(defun my/image-unwanted-message-p (msg &rest objects)
  "Return non-nil if MSG is unwanted.
For these purposes, a MSG is unwanted if (after formatting) it is
exactly the string \"Type C-c C-c to view the image as text.\"."
  (let ((msg (apply #'format (cons msg objects))))
    (string-equal msg "Type C-c C-c to view the image as text.")))

(defun my/image-suppress-messages (fn)
  "Suppress unwanted `message' calls in FN."
  (my/with-advice
      ((#'message :before-until #'my/image-unwanted-message-p))
    (funcall fn)))

(advice-add #'image-mode :around #'my/image-suppress-messages)

Here my/with-advice is this macro that I wrote for a previous problem; it's proven to be very handy for a lot of different tasks. I'm using it here because I'm a little leery about applying permanent advice to something as ubiquitous as message, even if that advice doesn't do anything most of the time.

(defmacro my/with-advice (adlist &rest body)
  "Execute BODY with temporary advice in ADLIST.

Each element of ADLIST should be a list of the form
  (SYMBOL WHERE FUNCTION [PROPS])
suitable for passing to `advice-add'.  The BODY is wrapped in an
`unwind-protect' form, so the advice will be removed even in the
event of an error or nonlocal exit."
  (declare (debug ((&rest (&rest form)) body))
           (indent 1))
  `(progn
     ,@(mapcar (lambda (adform)
                 (cons 'advice-add adform))
               adlist)
     (unwind-protect (progn ,@body)
       ,@(mapcar (lambda (adform)
                   `(advice-remove ,(car adform) ,(nth 2 adform)))
                 adlist))))

Note that the manual cautions not to advise primitives (including message), but I think it's okay here because (1) all the calls we want to suppress are from lisp anyway; (2) any extraneous calls should pass through transparently; and (3) the advice machinery can't be calling message here, because you'd be getting messages about it.