Handle buffer move/select/swap to last win nr +1 (#14015)

problem:
The following error messages are shown.

When trying to move, select or swap the current buffer,
to a window nr greater than the total number of open windows.

For example:
With only one window open.
`SPC b 2`
>ad-Advice-select-window: Wrong type argument: window-live-p, nil

In the Buffer Transient State (`SPC b .`):
- `C-2` (`spacemacs/buffer-transient-state/winum-select-window-2`)
>Wrong type argument: window-valid-p, #<window 12>

- `2` (`spacemacs/buffer-transient-state/move-buffer-window-no-follow-2`)
>Wrong type argument: window-live-p, #<window 14>

- `M-2` (`spacemacs/buffer-transient-state/swap-buffer-window-no-follow-2`)
>Wrong type argument: stringp, nil

Solution:
Show a descriptive message, if the target window nr is greater than the number
of open windows. And ignore the LV buffer (hydra).

CHANGELOG.develop

@@ -1363,6 +1363,7 @@ Other:
   - Fixed ~SPC h f~ =helm-spacemacs-help-faq= (thanks to duianto)
   - Fixed =cl= package deprecated =letf= (thanks to duianto)
   - Fixed origami bindings in normal mode (thanks to Tomasz Kowal)
+  - Handled buffer move/select/swap to last window nr +1 (thanks to duianto)
   - Set =evil-undo-system= to =undo-tree= (thanks to duianto)
 *** Layer changes and fixes
 **** Agda

layers/+spacemacs/spacemacs-defaults/funcs.el

@@ -261,30 +261,35 @@ Dedicated (locked) windows are left untouched."
   "Moves a buffer to a window, using the spacemacs numbering. follow-focus-p
 controls whether focus moves to new window (with buffer), or stays on current"
   (interactive)
-  (let ((b (current-buffer))
-        (w1 (selected-window))
-        (w2 (winum-get-window-by-number windownum)))
-    (unless (eq w1 w2)
-      (set-window-buffer w2 b)
-      (switch-to-prev-buffer)
-      (unrecord-window-buffer w1 b)))
-  (when follow-focus-p (select-window (winum-get-window-by-number windownum))))
+  (if (> windownum (length (window-list)))
+      (message "No window numbered %s" windownum)
+    (let ((b (current-buffer))
+          (w1 (selected-window))
+          (w2 (winum-get-window-by-number windownum)))
+      (unless (eq w1 w2)
+        (set-window-buffer w2 b)
+        (switch-to-prev-buffer)
+        (unrecord-window-buffer w1 b))
+      (when follow-focus-p
+        (select-window (winum-get-window-by-number windownum))))))
 
 (defun spacemacs/swap-buffers-to-window (windownum follow-focus-p)
   "Swaps visible buffers between active window and selected window.
 follow-focus-p controls whether focus moves to new window (with buffer), or
 stays on current"
   (interactive)
-  (let* ((b1 (current-buffer))
-         (w1 (selected-window))
-         (w2 (winum-get-window-by-number windownum))
-         (b2 (window-buffer w2)))
-    (unless (eq w1 w2)
-      (set-window-buffer w1 b2)
-      (set-window-buffer w2 b1)
-      (unrecord-window-buffer w1 b1)
-      (unrecord-window-buffer w2 b2)))
-  (when follow-focus-p (winum-select-window-by-number windownum)))
+  (if (> windownum (length (window-list)))
+      (message "No window numbered %s" windownum)
+    (let* ((b1 (current-buffer))
+           (w1 (selected-window))
+           (w2 (winum-get-window-by-number windownum))
+           (b2 (window-buffer w2)))
+      (unless (eq w1 w2)
+        (set-window-buffer w1 b2)
+        (set-window-buffer w2 b1)
+        (unrecord-window-buffer w1 b1)
+        (unrecord-window-buffer w2 b2)))
+    (when follow-focus-p (winum-select-window-by-number windownum))))
 
 (dotimes (i 9)
   (let ((n (+ i 1)))

layers/+spacemacs/spacemacs-navigation/packages.el

@@ -431,7 +431,7 @@
     (progn
       (setq winum-auto-assign-0-to-minibuffer nil
             winum-auto-setup-mode-line nil
-            winum-ignored-buffers '(" *which-key*"))
+            winum-ignored-buffers '(" *LV*" " *which-key*"))
       (spacemacs/set-leader-keys
         "`" 'winum-select-window-by-number
         "²" 'winum-select-window-by-number