;; Test case for force-mode-line-update.
;;
;; Load this file into a new buffer.
;;
;; It should give a menu called "AAA" with a "Switch to BBB" item.
;; Clicking on the item switches the menu to BBB, which is again a
;; similar menu which allows you to switch back to AAA.
;;
;; Using the "Force to BBB" menu item, on the other hand, doesn't switch
;; the menu.  Another event somewhere is needed for the menu bar
;; change to take effect.

(defvar test-map (make-sparse-keymap))

(defun menu-A ()
  (define-key test-map [menu-bar]
    (make-sparse-keymap "Menu"))
  (define-key test-map [menu-bar menu-a]
    (cons "AAA" (make-sparse-keymap "AAA")))
  (define-key test-map [menu-bar menu-a force]
    '(menu-item "Force to BBB" test-force-mode-line-update))
  (define-key test-map [menu-bar menu-a switch]
    '(menu-item "Switch to BBB" test-toggle-menubar)))

(defun menu-B ()
  (define-key test-map [menu-bar]
    (make-sparse-keymap "Menu"))
  (define-key test-map [menu-bar menu-b]
    (cons "BBB" (make-sparse-keymap "BBB")))
  (define-key test-map [menu-bar menu-b force]
    '(menu-item "Force to AAA" test-force-mode-line-update))
  (define-key test-map [menu-bar menu-b switch]
    '(menu-item "Switch to AAA" test-toggle-menubar)))


(defun test-toggle-menubar ()
  (interactive)
  (if (lookup-key test-map [menu-bar menu-a])
      (menu-B)
    (menu-A))
  (force-mode-line-update t))

;; This is the same as toggle except that it changes buffer beforehand.
;; Tests if force-mode-line-update truly updates all buffers.

(defun test-force-mode-line-update ()
  (interactive)
  (with-current-buffer (get-buffer-create "dummy")
    (test-toggle-menubar)))

(menu-A)
(use-local-map test-map)