Copy in some minor bug fixes from the trunk.

[gnu-emacs] / lisp / mwheel.el

diff --git a/lisp/mwheel.el b/lisp/mwheel.el
index 365875745237a67cc3adee3eee6f542d22b2edfa..908dc3a6fff6cb606bc44943959d1eb637fcfbff 100644 (file)
--- a/lisp/mwheel.el
+++ b/lisp/mwheel.el
@@ -1,6 +1,7 @@
 ;;; mwheel.el --- Wheel mouse support
 
-;; Copyright (C) 1998,2000,2001,2002  Free Software Foundation, Inc.
+;; Copyright (C) 1998, 2000, 2001, 2002, 2002, 2004,
+;;   2005, 2006, 2007, 2008 Free Software Foundation, Inc.
 ;; Maintainer: William M. Perry <wmperry@gnu.org>
 ;; Keywords: mouse
 
@@ -8,7 +9,7 @@
 
 ;; GNU Emacs is free software; you can redistribute it and/or modify
 ;; it under the terms of the GNU General Public License as published by
-;; the Free Software Foundation; either version 2, or (at your option)
+;; the Free Software Foundation; either version 3, or (at your option)
 ;; any later version.
 
 ;; GNU Emacs is distributed in the hope that it will be useful,
@@ -18,8 +19,8 @@
 
 ;; You should have received a copy of the GNU General Public License
 ;; along with GNU Emacs; see the file COPYING.  If not, write to the
-;; Free Software Foundation, Inc., 59 Temple Place - Suite 330,
-;; Boston, MA 02111-1307, USA.
+;; Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
+;; Boston, MA 02110-1301, USA.
 
 ;;; Commentary:
 
@@ -58,7 +59,7 @@
                         'mouse-wheel-down-event)
 (defcustom mouse-wheel-down-event
   ;; In the latest versions of XEmacs, we could just use mouse-%s as well.
-  (if (memq system-type '(windows-nt macos))
+  (if (memq window-system '(w32 mac))
       'wheel-up
     (intern (format (if (featurep 'xemacs) "button%s" "mouse-%s")
                    mouse-wheel-down-button)))
@@ -72,11 +73,11 @@
                         'mouse-wheel-up-event)
 (defcustom mouse-wheel-up-event
   ;; In the latest versions of XEmacs, we could just use mouse-%s as well.
-  (if (memq system-type '(windows-nt macos))
+  (if (memq window-system '(w32 mac))
       'wheel-down
     (intern (format (if (featurep 'xemacs) "button%s" "mouse-%s")
                    mouse-wheel-up-button)))
-  "Event used for scrolling down."
+  "Event used for scrolling up."
   :group 'mouse
   :type 'symbol
   :set 'mouse-wheel-change-button)
@@ -90,7 +91,7 @@
                  mouse-wheel-click-button))
   "Event that should be temporarily inhibited after mouse scrolling.
 The mouse wheel is typically on the mouse-2 button, so it may easily
-happen that text is accidentially yanked into the buffer when
+happen that text is accidentally yanked into the buffer when
 scrolling with the mouse wheel.  To prevent that, this variable can be
 set to the event sent when clicking on the mouse wheel button."
   :group 'mouse
@@ -137,7 +138,7 @@ less than a full screen."
                     (integer :tag "Specific # of lines")
                     (float :tag "Fraction of window"))))))
 
-(defcustom mouse-wheel-progessive-speed t
+(defcustom mouse-wheel-progressive-speed t
   "If non-nil, the faster the user moves the wheel, the faster the scrolling.
 Note that this has no effect when `mouse-wheel-scroll-amount' specifies
 a \"near full screen\" scroll or when the mouse wheel sends key instead
@@ -197,14 +198,31 @@ This should only be bound to mouse buttons 4 and 5."
       (let ((list-elt mouse-wheel-scroll-amount))
        (while (consp (setq amt (pop list-elt))))))
     (if (floatp amt) (setq amt (1+ (truncate (* amt (window-height))))))
-    (when (and mouse-wheel-progessive-speed (numberp amt))
+    (when (and mouse-wheel-progressive-speed (numberp amt))
       ;; When the double-mouse-N comes in, a mouse-N has been executed already,
       ;; So by adding things up we get a squaring up (1, 3, 6, 10, 15, ...).
       (setq amt (* amt (event-click-count event))))
     (unwind-protect
        (let ((button (mwheel-event-button event)))
-         (cond ((eq button mouse-wheel-down-event) (scroll-down amt))
-               ((eq button mouse-wheel-up-event) (scroll-up amt))
+         (cond ((eq button mouse-wheel-down-event)
+                 (condition-case nil (scroll-down amt)
+                   ;; Make sure we do indeed scroll to the beginning of
+                   ;; the buffer.
+                   (beginning-of-buffer
+                    (unwind-protect
+                        (scroll-down)
+                      ;; If the first scroll succeeded, then some scrolling
+                      ;; is possible: keep scrolling til the beginning but
+                      ;; do not signal an error.  For some reason, we have
+                      ;; to do it even if the first scroll signalled an
+                      ;; error, because otherwise the window is recentered
+                      ;; for a reason that escapes me.  This problem seems
+                      ;; to only affect scroll-down.  --Stef
+                      (set-window-start (selected-window) (point-min))))))
+               ((eq button mouse-wheel-up-event)
+                 (condition-case nil (scroll-up amt)
+                   ;; Make sure we do indeed scroll to the end of the buffer.
+                   (end-of-buffer (while t (scroll-up)))))
                (t (error "Bad binding in mwheel-scroll"))))
       (if curwin (select-window curwin))))
   (when (and mouse-wheel-click-event mouse-wheel-inhibit-click-time)
@@ -219,7 +237,7 @@ This should only be bound to mouse buttons 4 and 5."
 (define-minor-mode mouse-wheel-mode
   "Toggle mouse wheel support.
 With prefix argument ARG, turn on if positive, otherwise off.
-Returns non-nil if the new state is enabled."
+Return non-nil if the new state is enabled."
   :global t
   :group 'mouse
   (let* ((dn mouse-wheel-down-event)
@@ -250,4 +268,5 @@ Returns non-nil if the new state is enabled."
 
 (provide 'mwheel)
 
+;; arch-tag: 50ed00e7-3686-4b7a-8037-fb31aa5c237f
 ;;; mwheel.el ends here