(mouse-buffer-menu): If lots of buffers, group them into multiple panes.

1 files changed, 59 insertions, 38 deletions

diff --git a/lisp/mouse.el b/lisp/mouse.el
index 98711f4e767..b91f0015263 100644
--- a/lisp/mouse.el
+++ b/lisp/mouse.el
@@ -1158,50 +1158,71 @@ This switches buffers in the window that you clicked on,
 and selects that window."
   (interactive "e")
   (mouse-minibuffer-check event)
-  (let ((menu
-         (list "Buffer Menu"
-               (cons "Select Buffer"
-                     (let ((tail (buffer-list))
-                           (maxbuf 0)
-                           head)
-                       (while tail
-                         (or (eq ?\ (aref (buffer-name (car tail)) 0))
-                             (setq maxbuf
-                                   (max maxbuf
-                                        (length (buffer-name (car tail))))))
-                         (setq tail (cdr tail)))
-                       (setq tail (buffer-list))
-                       (while tail
-                         (let ((elt (car tail)))
-                           (if (not (string-match "^ "
-                                                  (buffer-name elt)))
-                               (setq head
-                                (cons
-                                 (cons
-                                  (format
-                                   (format "%%%ds  %%s%%s  %%s" maxbuf)
-                                   (buffer-name elt)
-                                   (if (buffer-modified-p elt) "*" " ")
-                                   (save-excursion
-                                     (set-buffer elt)
-                                     (if buffer-read-only "%" " "))
-                                   (or (buffer-file-name elt) 
-                                       (save-excursion
-                                         (set-buffer elt)
-                                         (if list-buffers-directory
-                                             (expand-file-name
-                                              list-buffers-directory)))
-                                       ""))
-                                  elt)
-                                 head))))
-                         (setq tail (cdr tail)))
-                       (reverse head))))))
+  (let* ((buffers
+          ;; Make an alist of (MENU-ITEM . BUFFER).
+          (let ((tail (buffer-list))
+                (maxlen 0)
+                head)
+            (while tail
+              (or (eq ?\ (aref (buffer-name (car tail)) 0))
+                  (setq maxlen
+                        (max maxlen
+                             (length (buffer-name (car tail))))))
+              (setq tail (cdr tail)))
+            (setq tail (buffer-list))
+            (while tail
+              (let ((elt (car tail)))
+                (if (not (string-match "^ "
+                                       (buffer-name elt)))
+                    (setq head
+                          (cons
+                           (cons
+                            (format
+                             (format "%%%ds  %%s%%s  %%s" maxlen)
+                             (buffer-name elt)
+                             (if (buffer-modified-p elt) "*" " ")
+                             (save-excursion
+                               (set-buffer elt)
+                               (if buffer-read-only "%" " "))
+                             (or (buffer-file-name elt) 
+                                 (save-excursion
+                                   (set-buffer elt)
+                                   (if list-buffers-directory
+                                       (expand-file-name
+                                        list-buffers-directory)))
+                                 ""))
+                            elt)
+                           head))))
+              (setq tail (cdr tail)))
+            head))
+         (menu
+          ;; If we have lots of buffers, divide them into groups of 20
+          ;; and make a pane (or submenu) for each one.
+          (if (> (length buffers) 30)
+              (let ((buffers (reverse buffers)) sublists next
+                    (i 1))
+                (while buffers
+                  ;; Pull off the next 20 buffers
+                  ;; and make them the next element of sublist.
+                  (setq next (nthcdr 20 buffers))
+                  (if next
+                      (setcdr (nthcdr 19 buffers) nil))
+                  (setq sublists (cons (cons (format "Buffers %d" i) buffers)
+                                       sublists))
+                  (setq i (1+ i))
+                  (setq buffers next))
+                (cons "Buffer Menu" (nreverse sublists)))
+            ;; Few buffers--put them all in one pane.
+            (list "Buffer Menu" (cons "Select Buffer" buffers)))))
+    (setq foo menu)
     (let ((buf (x-popup-menu event menu))
           (window (posn-window (event-start event))))
       (if buf
           (progn
             (or (framep window) (select-window window))
             (switch-to-buffer buf))))))
+
+(defun mouse-buffer-menu-split (alist)
 
 ;;; These need to be rewritten for the new scroll bar implementation.