Add frame-use-time, get-mru-frame, use mru frame in delete-frame (bug#80397)

* lisp/frame.el (get-mru-frame): New defun.
* src/frame.c (delete_frame): Call 'get-mru-frame' (when force
is not Qnoelisp) to select the most recently used frame that is
not the deleted frame as the candidate to select.
(syms_of_frame): Qget_mru_frame new DEFSYM.
* doc/lispref/frames.texi: Document the new functions.
* etc/NEWS: Announce the new functions.

1 files changed, 56 insertions, 35 deletions

diff --git a/src/frame.c b/src/frame.c
index 8dff1470149..6b5d8942db4 100644
--- a/src/frame.c
+++ b/src/frame.c
@@ -2748,57 +2748,77 @@ delete_frame (Lisp_Object frame, Lisp_Object force)
         do_switch_frame (mru_rooted_frame (f), 0, 1, Qnil);
       else
         {
-          Lisp_Object tail;
-          eassume (CONSP (Vframe_list));
-
-          /* Look for another visible frame on the same terminal.
-             Do not call next_frame here because it may loop forever.
-             See https://debbugs.gnu.org/cgi/bugreport.cgi?bug=15025.  */
-          FOR_EACH_FRAME (tail, frame1)
+          frame1 = Qnil;
+          if (!EQ (force, Qnoelisp))
             {
-              struct frame *f1 = XFRAME (frame1);
-
-              if (!EQ (frame, frame1)
-                  && !FRAME_TOOLTIP_P (f1)
-                  && FRAME_TERMINAL (f) == FRAME_TERMINAL (f1)
-                  && FRAME_VISIBLE_P (f1))
-                break;
+              /* Find the most recently used visible frame among all
+                 frames on the same terminal as FRAME, excluding FRAME
+                 which we are about to delete.  */
+              frame1 = calln (Qget_mru_frame, Qvisible, frame);
+              if (!NILP (frame1))
+                {
+                  struct frame *f1 = XFRAME (frame1);
+                  if (FRAME_TOOLTIP_P (f1)
+                      || FRAME_TERMINAL (f) != FRAME_TERMINAL (f1)
+                      || !FRAME_VISIBLE_P (f1))
+                    frame1 = Qnil;
+                }
             }
 
-          /* If there is none, find *some* other frame.  */
-          if (NILP (frame1) || EQ (frame1, frame))
+          if (NILP (frame1))
             {
+              Lisp_Object tail;
+              eassume (CONSP (Vframe_list));
+
+              /* Look for another visible frame on the same terminal.
+                 Do not call next_frame here because it may loop forever.
+                 See https://debbugs.gnu.org/cgi/bugreport.cgi?bug=15025.  */
               FOR_EACH_FRAME (tail, frame1)
                 {
                   struct frame *f1 = XFRAME (frame1);
 
                   if (!EQ (frame, frame1)
-                      && FRAME_LIVE_P (f1)
-                      && !FRAME_TOOLTIP_P (f1))
+                      && !FRAME_TOOLTIP_P (f1)
+                      && FRAME_TERMINAL (f) == FRAME_TERMINAL (f1)
+                      && FRAME_VISIBLE_P (f1))
+                    break;
+                }
+
+              /* If there is none, find *some* other frame.  */
+              if (NILP (frame1) || EQ (frame1, frame))
+                {
+                  FOR_EACH_FRAME (tail, frame1)
                     {
-                      if (FRAME_TERMCAP_P (f1) || FRAME_MSDOS_P (f1))
-                        {
-                          Lisp_Object top_frame = FRAME_TTY (f1)->top_frame;
+                      struct frame *f1 = XFRAME (frame1);
 
-                          if (!EQ (top_frame, frame))
-                            frame1 = top_frame;
+                      if (!EQ (frame, frame1)
+                          && FRAME_LIVE_P (f1)
+                          && !FRAME_TOOLTIP_P (f1))
+                        {
+                          if (FRAME_TERMCAP_P (f1) || FRAME_MSDOS_P (f1))
+                            {
+                              Lisp_Object top_frame = FRAME_TTY (f1)->top_frame;
+
+                              if (!EQ (top_frame, frame))
+                                frame1 = top_frame;
+                            }
+                          break;
                         }
-                      break;
                     }
                 }
-            }
 #ifdef NS_IMPL_COCOA
-          else
-            {
-              /* Under NS, there is no system mechanism for choosing a new
-                 window to get focus -- it is left to application code.
-                 So the portion of THIS application interfacing with NS
-                 needs to make the frame we switch to the key window.  */
-              struct frame *f1 = XFRAME (frame1);
-              if (FRAME_NS_P (f1))
-                ns_make_frame_key_window (f1);
-            }
+              else
+                {
+                  /* Under NS, there is no system mechanism for choosing a new
+                     window to get focus -- it is left to application code.
+                     So the portion of THIS application interfacing with NS
+                     needs to make the frame we switch to the key window.  */
+                  struct frame *f1 = XFRAME (frame1);
+                  if (FRAME_NS_P (f1))
+                    ns_make_frame_key_window (f1);
+                }
 #endif
+            }
 
           do_switch_frame (frame1, 0, 1, Qnil);
           sf = SELECTED_FRAME ();
@@ -7185,6 +7205,7 @@ syms_of_frame (void)
   DEFSYM (Qframe_monitor_attributes, "frame-monitor-attributes");
   DEFSYM (Qwindow__pixel_to_total, "window--pixel-to-total");
   DEFSYM (Qmake_initial_minibuffer_frame, "make-initial-minibuffer-frame");
+  DEFSYM (Qget_mru_frame, "get-mru-frame");
   DEFSYM (Qexplicit_name, "explicit-name");
   DEFSYM (Qheight, "height");
   DEFSYM (Qicon, "icon");