bug#14841: Frames created invisible have their visibility parameter set to t

[Eli Zaretskii]

> From: Juanma Barranquero <lekktu@gmail.com>
> Date: Wed, 24 Jul 2013 18:50:03 +0200
> Cc: 14841@debbugs.gnu.org
> 
>  ;;; .emacs
>  (let ((f (selected-frame)))
>    (make-frame)
>    (delete-frame f))
> ;;; .emacs ends here
> 
>  emacs
> 
>  =>
> 
>  Warning (initialization): An error occurred while loading
> `c:/Devel/emacs/test/.emacs':
> 
>  error: Attempt to delete the sole visible or iconified frame

Btw, this trivial modification will avoid the problem:

    (let ((f (selected-frame))
          (f1 (make-frame)))
      (make-frame-visible f1)
      (delete-frame f))

as will this:

    (let ((f (selected-frame))
          (f1 (make-frame)))
      (sit-for 0)
      (delete-frame f))

The problem here is that x-create-frame-with-faces does this:

  (setq parameters (x-handle-named-frame-geometry parameters))
  (let* ((params (copy-tree parameters))
         (visibility-spec (assq 'visibility parameters))
         (delayed-params '(foreground-color background-color font
                           border-color cursor-color mouse-color
                           visibility scroll-bar-foreground
                           scroll-bar-background))
         frame success)
    (dolist (param delayed-params)
      (setq params (assq-delete-all param params)))
    (setq frame (x-create-frame `((visibility . nil) . ,params))) <<<<<<<<<
    (unwind-protect
        (progn
          (x-setup-function-keys frame)
          (x-handle-reverse-video frame parameters)
          (frame-set-background-mode frame t)
          (face-set-after-frame-default frame parameters)
          (if (null visibility-spec)
              (make-frame-visible frame)                            <<<<<<<
            (modify-frame-parameters frame (list visibility-spec))) <<<<<<<

IOW, it first creates a frame that is invisible, and only then applies
the visibility spec.  So you must wait for the frame to come up before
you can delete the initial frame.