Handle glitch in delayed autoselection of windows.

* window.el (mouse-autoselect-window-position-1): New variable.
(mouse-autoselect-window-cancel)
(mouse-autoselect-window-select, handle-select-window): With
delayed autoselection select window only if mouse moves after
selecting its frame.

2 files changed, 36 insertions, 13 deletions

diff --git a/lisp/ChangeLog b/lisp/ChangeLog
index 0882a519f86..42b2fc474f9 100644
--- a/lisp/ChangeLog
+++ b/lisp/ChangeLog
@@ -1,3 +1,11 @@
+2014-12-24  Martin Rudalics  <rudalics@gmx.at>
+
+        * window.el (mouse-autoselect-window-position-1): New variable.
+        (mouse-autoselect-window-cancel)
+        (mouse-autoselect-window-select, handle-select-window): With
+        delayed autoselection select window only if mouse moves after
+        selecting its frame.
+
 2014-12-24  Michael Albinus  <michael.albinus@gmx.de>
 
         * eshell/esh-ext.el (eshell-find-interpreter): Expand relative
diff --git a/lisp/window.el b/lisp/window.el
index c95b0d6d418..cb9f1ed9b4c 100644
--- a/lisp/window.el
+++ b/lisp/window.el
@@ -7798,6 +7798,9 @@ With arg N, put point N/10 of the way from the true end."
 (defvar mouse-autoselect-window-timer nil
   "Timer used by delayed window autoselection.")
 
+(defvar mouse-autoselect-window-position-1 nil
+  "First mouse position recorded by delayed window autoselection.")
+
 (defvar mouse-autoselect-window-position nil
   "Last mouse position recorded by delayed window autoselection.")
 
@@ -7822,6 +7825,7 @@ Optional argument FORCE means cancel unconditionally."
                         (memq (nth 4 (event-end last-input-event))
                               '(handle end-scroll)))))
     (setq mouse-autoselect-window-state nil)
+    (setq mouse-autoselect-window-position-1 nil)
     (when (timerp mouse-autoselect-window-timer)
       (cancel-timer mouse-autoselect-window-timer))
     (remove-hook 'pre-command-hook 'mouse-autoselect-window-cancel)))
@@ -7863,21 +7867,32 @@ is active.  This function is run by `mouse-autoselect-window-timer'."
        ;; A menu / popup dialog is active or the mouse is not on the
        ;; text region of WINDOW: Suspend autoselection temporarily.
        (mouse-autoselect-window-start mouse-position nil t))
-      ((eq mouse-autoselect-window-state 'suspend)
+      ((or (eq mouse-autoselect-window-state 'suspend)
+           ;; When the mouse is at its first recorded position, restart
+           ;; delayed autoselection.  This works around a scenario with
+           ;; two two-window frames with identic dimensions: Select the
+           ;; first window of the first frame, switch to the second
+           ;; frame, move the mouse to its second window, minimize the
+           ;; second frame.  Now the second window of the first frame
+           ;; gets selected although the mouse never really "moved" into
+           ;; that window.
+           (and (numberp mouse-autoselect-window)
+                (equal (mouse-position) mouse-autoselect-window-position-1)))
        ;; Delayed autoselection was temporarily suspended, reenable it.
        (mouse-autoselect-window-start mouse-position))
       ((and window (not (eq window (selected-window)))
             (or (not (numberp mouse-autoselect-window))
-                (and (> mouse-autoselect-window 0)
-                     ;; If `mouse-autoselect-window' is positive, select
-                     ;; window if the window is the same as before.
+                (and (>= mouse-autoselect-window 0)
+                     ;; If `mouse-autoselect-window' is non-negative,
+                     ;; select window if it's the same as before.
                      (eq window mouse-autoselect-window-window))
-                ;; Otherwise select window if the mouse is at the same
-                ;; position as before.  Observe that the first test after
-                ;; starting autoselection usually fails since the value of
-                ;; `mouse-autoselect-window-position' recorded there is the
-                ;; position where the mouse has entered the new window and
-                ;; not necessarily where the mouse has stopped moving.
+                ;; Otherwise select window iff the mouse is at the same
+                ;; position as before.  Observe that the first test
+                ;; after starting autoselection usually fails since the
+                ;; value of `mouse-autoselect-window-position' recorded
+                ;; there is the position where the mouse has entered the
+                ;; new window and not necessarily where the mouse has
+                ;; stopped moving.
                 (equal mouse-position mouse-autoselect-window-position))
             ;; The minibuffer is a candidate window if it's active.
             (or (not (window-minibuffer-p window))
@@ -7921,14 +7936,14 @@ is active.  This function is run by `mouse-autoselect-window-timer'."
                      (not (minibuffer-window-active-p window)))
                 ;; Don't switch when autoselection shall be delayed.
                 (and (numberp mouse-autoselect-window)
-                     (not (zerop mouse-autoselect-window))
                      (not (eq mouse-autoselect-window-state 'select))
-                     (progn
+                     (let ((position (mouse-position)))
                        ;; Cancel any delayed autoselection.
                        (mouse-autoselect-window-cancel t)
                        ;; Start delayed autoselection from current mouse
                        ;; position and window.
-                       (mouse-autoselect-window-start (mouse-position) window)
+                       (setq mouse-autoselect-window-position-1 position)
+                       (mouse-autoselect-window-start position window)
                        ;; Executing a command cancels delayed autoselection.
                        (add-hook
                         'pre-command-hook 'mouse-autoselect-window-cancel))))