bug#33871: 27.0.50; Revert Dired window saved in window configuration

[Juri Linkov]

>> Ok, let's add the WINDOW argument.  This means that most hooks
>> will need to call 'with-selected-window' explicitly.  But maybe
>> there will be hooks that don't need to select a window.
>
> (setq-default window-set-context-function
>               (lambda (w)
>               (let ((point (window-point w)))
>                 (with-current-buffer (window-buffer w)
>                     `((front-context-string
>                        . ,(buffer-substring-no-properties
>                            point (min (+ point 16) (point-max))))
>                       (rear-context-string
>                        . ,(buffer-substring-no-properties
>                            point (max (- point 16) (point-min)))))))))
>
> should suffice to make 'buffer-substring-no-properties' work.  Note that
> if you select the window beforehand, 'selected-window' will not return a
> meaningful value in the body of the function called.  This is a problem
> of many "hooks" like 'mode-line-format' or 'window-configuration-hook'.
> The comfort you get comes at the price of a lack of generality.

Thanks.  Is it possible to avoid 'with-selected-window' in other hooks?
Maybe something like this:

(setq-default window-use-context-function
              (lambda (w context)
                (let ((point (window-point w)))
                  (with-current-buffer (window-buffer w)
                    (goto-char point)
                    (when-let ((f (alist-get 'front-context-string context)))
                      (search-forward f (point-max) t)
                      (goto-char (match-beginning 0)))
                    (when-let ((r (alist-get 'rear-context-string context)))
                      (search-backward r (point-min) t)
                      (goto-char (match-end 0)))
                    (setq point (point)))
                  (set-window-point w point))))

and for Dired:

diff --git a/lisp/dired.el b/lisp/dired.el
index 9e3b888df14..fc8da1635f9 100644
--- a/lisp/dired.el
+++ b/lisp/dired.el
@@ -2743,6 +2745,24 @@ dired-mode
               '(dired-font-lock-keywords t nil nil beginning-of-line))
   (setq-local desktop-save-buffer 'dired-desktop-buffer-misc-data)
   (setq-local grep-read-files-function #'dired-grep-read-files)
+  (setq-local window-set-context-function
+              (lambda (w)
+                (let ((point (window-point w)))
+                  (with-current-buffer (window-buffer w)
+                    (goto-char point)
+                    (if-let ((f (dired-get-filename nil t)))
+                        `((dired-filename . ,f))
+                      `((position . ,(point))))))))
+  (setq-local window-use-context-function
+              (lambda (w context)
+                (let ((point (window-point w)))
+                  (with-current-buffer (window-buffer w)
+                    (if-let ((f (alist-get 'dired-filename context)))
+                        (dired-goto-file f)
+                      (when-let ((p (alist-get 'position context)))
+                        (goto-char p)))
+                    (setq point (point)))
+                  (set-window-point w point))))
   (setq dired-switches-alist nil)
   (hack-dir-local-variables-non-file-buffer) ; before sorting
   (dired-sort-other dired-actual-switches t)