disabled cavas demo code by default since people have issues building. it can be enabled explicitly

8 files changed, 408 insertions, 280 deletions

diff --git a/README.xwidget b/README.xwidget
index 74054165edd..bec536393a1 100644
--- a/README.xwidget
+++ b/README.xwidget
@@ -1319,9 +1319,9 @@ for (var i=0; i<frames.length; i++)
   }
 
 
-** TODO support downstreams
+** support downstreams
 http://aur.archlinux.org/packages.php?ID=48230
-
+** TODO the proof of concept canvas code should be disabled by default.
 ** TODO advi
 active dvi viewer. investigate if it could be xwidgetified.
 advi supports embedding inside presentations.
diff --git a/configure.in b/configure.in
index 4a3d5f5d900..adb9d1e8795 100644
--- a/configure.in
+++ b/configure.in
@@ -1994,16 +1994,18 @@ if test "${with_xwidgets}" != "no"; then
         AC_DEFINE(HAVE_WEBKIT_OSR, 1, [Define to 1 if you have webkit_osr support.])     
     fi
   fi
-  
-  CLUTTER_REQUIRED=1.0.0
+
+  if test "${with_xwdemo}"  = "yes"; then
+#clutter and goocanvas are just proof of concept so disable for now  
+  CLUTTER_REQUIRED=1.0.0   
   CLUTTER_MODULES="clutter-gtk-1.0 >= $CLUTTER_REQUIRED"
 
   PKG_CHECK_MODULES(CLUTTER, $CLUTTER_MODULES, HAVE_CLUTTER=yes, HAVE_CLUTTER=no)
-  if test $HAVE_CLUTTER = yes; then
+  if test $HAVE_CLUTTER = yes;  then
      AC_DEFINE(HAVE_CLUTTER, 1, [Define to 1 if you have clutter support.])
   fi
 
-#TODO  
+
   GOOCANVAS_REQUIRED=1.4.0
   GOOCANVAS_MODULES="goocanvasgtk-3.0 >= $GOOCANVAS_REQUIRED"
 
@@ -2011,7 +2013,7 @@ if test "${with_xwidgets}" != "no"; then
   if test $HAVE_GOOCANVAS = yes; then
      AC_DEFINE(HAVE_GOOCANVAS, 1, [Define to 1 if you have goocanvas support.])
   fi
-
+  fi
 fi
 
 
diff --git a/lisp/ChangeLog b/lisp/ChangeLog
index b4b95fb4074..7ea1dffe1c2 100644
--- a/lisp/ChangeLog
+++ b/lisp/ChangeLog
@@ -1,3 +1,39 @@
+2011-09-02  Chong Yidong  <cyd@stupidchicken.com>
+
+        * window.el (display-buffer-alist): Doc fix.
+        (display-buffer): Add docstring.  Don't treat
+        display-buffer-default specially.
+        (display-buffer-reuse-selected-window)
+        (display-buffer-same-window, display-buffer-maybe-same-window)
+        (display-buffer-reuse-window, display-buffer-pop-up-frame)
+        (display-buffer-pop-up-window)
+        (display-buffer-reuse-or-pop-window)
+        (display-buffer-use-some-window): New functions.
+        (display-buffer-default-action): Use them.
+        (display-buffer-default): Deleted.
+        (pop-to-buffer-1): Fix choice of actions.
+
+2011-09-02  Stefan Monnier  <monnier@iro.umontreal.ca>
+
+        * minibuffer.el (completion--insert-strings): Don't get confused by
+        completion entries that end with an LF char.
+
+2011-09-01  Eli Zaretskii  <eliz@gnu.org>
+
+        * window.el (frame-auto-delete, window-deletable-p): Doc fix.
+
+2011-09-01  Chong Yidong  <cyd@stupidchicken.com>
+
+        * window.el (display-buffer): Restore interactive spec.
+        (display-buffer-same-window, display-buffer-other-window):
+        New functions.
+        (pop-to-buffer-1): New function.  Use the above.
+        (pop-to-buffer, pop-to-buffer-same-window): Use it.
+        (pop-to-buffer-other-window, pop-to-buffer-other-frame): Delete.
+
+        * view.el (view-buffer-other-window, view-buffer-other-frame):
+        Just use pop-to-buffer.
+
 2011-09-01  Thierry Volpiatto  <thierry.volpiatto@gmail.com>
 
         * vc/vc-rcs.el (vc-rcs-responsible-p): Handle directories.  (Bug#9391)
@@ -44,8 +80,8 @@
         (display-buffer-alist-set-1, display-buffer-alist-set-2)
         (display-buffer-alist-set): Remove.
         (display-buffer-function, special-display-buffer-names)
-        (special-display-regexps, special-display-function): In
-        doc-string refer to display-buffer-window and quit-restore
+        (special-display-regexps, special-display-function):
+        In doc-string refer to display-buffer-window and quit-restore
         parameter.
         (pop-up-frame-alist, pop-up-frame-function, special-display-p)
         (special-display-frame-alist, special-display-popup-frame)
@@ -56,8 +92,8 @@
         (split-window-sensibly, window--try-to-split-window)
         (window--frame-usable-p, even-window-heights)
         (window--even-window-heights, window--display-buffer-1)
-        (window--display-buffer-2, display-buffer-other-frame): Restore
-        old Emacs 23 code, order and doc-strings where applicable.
+        (window--display-buffer-2, display-buffer-other-frame):
+        Restore old Emacs 23 code, order and doc-strings where applicable.
         (display-buffer-default, display-buffer-assq-regexp): New functions.
         (display-buffer-alist): Rewrite doc-string.
         (display-buffer-default-action)
@@ -69,8 +105,8 @@
         Restore Emacs 23 behavior but use
         window-normalize-buffer-to-switch-to.
         (pop-to-buffer-same-window): Rewrite.
-        (pop-to-buffer-other-window, pop-to-buffer-other-frame): Rewrite
-        using Emacs 23 options.
+        (pop-to-buffer-other-window, pop-to-buffer-other-frame):
+        Rewrite using Emacs 23 options.
 
 2011-08-31  Michael Albinus  <michael.albinus@gmx.de>
 
@@ -79,8 +115,8 @@
         (tramp-completion-file-name-regexp-separate)
         (tramp-completion-file-name-regexp-url): Don't use leading volume
         letter on win32 systems.  (Bug#5303, Bug#9311)
-        (tramp-drop-volume-letter): Simplify definition.  Suggested by
-        Stefan Monnier <monnier@iro.umontreal.ca>.
+        (tramp-drop-volume-letter): Simplify definition.
+        Suggested by Stefan Monnier <monnier@iro.umontreal.ca>.
 
 2011-08-30  Stefan Monnier  <monnier@iro.umontreal.ca>
 
diff --git a/lisp/gnus/ChangeLog b/lisp/gnus/ChangeLog
index 71872b21adb..8646f687420 100644
--- a/lisp/gnus/ChangeLog
+++ b/lisp/gnus/ChangeLog
@@ -1,3 +1,8 @@
+2011-09-01  Andrew Cohen  <cohen@andy.bu.edu>
+
+        * gnus-sum.el: When adding article headers to a summary buffer also
+        update gnus-newsgroup-articles (bug#9386).
+
 2011-08-30  Katsumi Yamaoka  <yamaoka@jpl.org>
 
         * auth-source.el: Autoload help-mode.
diff --git a/lisp/gnus/gnus-sum.el b/lisp/gnus/gnus-sum.el
index c01f91973a0..fd441c46d17 100644
--- a/lisp/gnus/gnus-sum.el
+++ b/lisp/gnus/gnus-sum.el
@@ -8630,6 +8630,8 @@ fetched for this group."
            'list gnus-newsgroup-headers
            (gnus-fetch-headers articles nil t)
            'gnus-article-sort-by-number))
+    (setq gnus-newsgroup-articles
+          (gnus-sorted-nunion gnus-newsgroup-articles articles))
     (gnus-summary-limit (append articles gnus-newsgroup-limit))))
 
 (defun gnus-summary-limit-exclude-dormant ()
@@ -9022,9 +9024,11 @@ non-numeric or nil fetch the number specified by the
                       (keep-lines
                        (regexp-opt ',(append refs (list id subject)))))))
               (gnus-fetch-headers (list last) (if (numberp limit)
-                                                  (* 2 limit) limit) t)))))
+                                                  (* 2 limit) limit) t))))
+         article-ids)
     (when (listp new-headers)
       (dolist (header new-headers)
+        (push (mail-header-number header) article-ids)
         (when (member (mail-header-number header) gnus-newsgroup-unselected)
           (push (mail-header-number header) gnus-newsgroup-unreads)
           (setq gnus-newsgroup-unselected
@@ -9035,6 +9039,8 @@ non-numeric or nil fetch the number specified by the
              (gnus-merge
               'list gnus-newsgroup-headers new-headers
               'gnus-article-sort-by-number)))
+      (setq gnus-newsgroup-articles
+            (gnus-sorted-nunion gnus-newsgroup-articles (nreverse article-ids)))
       (gnus-summary-limit-include-thread id))))
 
 (defun gnus-summary-refer-article (message-id)
@@ -12743,6 +12749,8 @@ returned."
                       gnus-newsgroup-headers
                       (gnus-fetch-headers articles)
                       'gnus-article-sort-by-number))
+    (setq gnus-newsgroup-articles
+          (gnus-sorted-nunion gnus-newsgroup-articles articles))
     ;; Suppress duplicates?
     (when gnus-suppress-duplicates
       (gnus-dup-suppress-articles))
diff --git a/lisp/minibuffer.el b/lisp/minibuffer.el
index 313298de97e..820b1599abb 100644
--- a/lisp/minibuffer.el
+++ b/lisp/minibuffer.el
@@ -1076,12 +1076,15 @@ It also eliminates runs of equal strings."
            (column 0)
            (rows (/ (length strings) columns))
            (row 0)
+           (first t)
            (laststring nil))
       ;; The insertion should be "sensible" no matter what choices were made
       ;; for the parameters above.
       (dolist (str strings)
         (unless (equal laststring str) ; Remove (consecutive) duplicates.
           (setq laststring str)
+          ;; FIXME: `string-width' doesn't pay attention to
+          ;; `display' properties.
           (let ((length (if (consp str)
                             (+ (string-width (car str))
                                (string-width (cadr str)))
@@ -1100,11 +1103,11 @@ It also eliminates runs of equal strings."
                     (forward-line 1)
                     (end-of-line)))
                 (insert " \t")
-                (set-text-properties (- (point) 1) (point)
+                (set-text-properties (1- (point)) (point)
                                      `(display (space :align-to ,column)))))
              (t
               ;; Horizontal format
-              (unless (bolp)
+              (unless first
                 (if (< wwidth (+ (max colwidth length) column))
                     ;; No space for `str' at point, move to next line.
                     (progn (insert "\n") (setq column 0))
@@ -1112,12 +1115,13 @@ It also eliminates runs of equal strings."
                   ;; Leave the space unpropertized so that in the case we're
                   ;; already past the goal column, there is still
                   ;; a space displayed.
-                  (set-text-properties (- (point) 1) (point)
+                  (set-text-properties (1- (point)) (point)
                                        ;; We can't just set tab-width, because
                                        ;; completion-setup-function will kill
                                        ;; all local variables :-(
                                        `(display (space :align-to ,column)))
                   nil))))
+            (setq first nil)
             (if (not (consp str))
                 (put-text-property (point) (progn (insert str) (point))
                                    'mouse-face 'highlight)
diff --git a/lisp/view.el b/lisp/view.el
index be011d217fc..96fecd9df1c 100644
--- a/lisp/view.el
+++ b/lisp/view.el
@@ -338,7 +338,8 @@ Optional argument EXIT-ACTION is either nil or a function with buffer as
 argument.  This function is called when finished viewing buffer.  Use
 this argument instead of explicitly setting `view-exit-action'."
   (interactive "bIn other window view buffer:\nP")
-  (pop-to-buffer-other-window buffer)
+  (let ((pop-up-windows t))
+    (pop-to-buffer buffer t))
   (view-mode-enter nil exit-action))
 
 ;;;###autoload
@@ -358,7 +359,8 @@ Optional argument EXIT-ACTION is either nil or a function with buffer as
 argument.  This function is called when finished viewing buffer.  Use
 this argument instead of explicitly setting `view-exit-action'."
   (interactive "bView buffer in other frame: \nP")
-  (pop-to-buffer-other-frame buffer)
+  (let ((pop-up-frames t))
+    (pop-to-buffer buffer t))
   (view-mode-enter nil exit-action))
 
 ;;;###autoload
diff --git a/lisp/window.el b/lisp/window.el
index 50deb035420..8bdf4131c51 100644
--- a/lisp/window.el
+++ b/lisp/window.el
@@ -2259,10 +2259,10 @@ and no others."
 
 ;;; Deleting windows.
 (defcustom frame-auto-delete 'automatic
-  "If non-nil, quitting a window can delete it's frame.
+  "If non-nil, quitting a window can delete its frame.
 If this variable is nil, functions that quit a window never
-delete the associated frame.  If this variable equals the symbol
-`automatic', a frame is deleted only if it the window is
+delete the associated frame.  If this variable's value is the
+symbol `automatic', a frame is deleted only if the window is
 dedicated or was created by `display-buffer'.  If this variable
 is t, a frame can be always deleted, even if it was created by
 `make-frame-command'.  Other values should not be used.
@@ -2282,8 +2282,8 @@ variable are `switch-to-prev-buffer', `delete-windows-on',
 
 (defun window-deletable-p (&optional window)
   "Return t if WINDOW can be safely deleted from its frame.
-Return `frame' if deleting WINDOW should delete its frame
-instead."
+Return `frame' if deleting WINDOW should also delete its
+frame."
   (setq window (window-normalize-any-window window))
   (unless ignore-window-parameters
     ;; Handle atomicity.
@@ -2304,7 +2304,7 @@ instead."
                  (other-visible-frames-p frame))
         ;; WINDOW is the root window of its frame.  Return `frame' but
         ;; only if WINDOW is (1) either dedicated or quit-restore's car
-        ;; is new-frame and the window still displays the same buffer
+        ;; is `new-frame' and the window still displays the same buffer
         ;; and (2) there are other frames left.
         'frame))
      ((and (not ignore-window-parameters)
@@ -4478,155 +4478,6 @@ Return WINDOW."
 The actual non-nil value of this variable will be copied to the
 `window-dedicated-p' flag.")
 
-(defun display-buffer-default (buffer-or-name &optional not-this-window frame)
-  "Make buffer BUFFER-OR-NAME appear in some window but don't select it.
-BUFFER-OR-NAME must be a buffer or the name of an existing
-buffer.  Return the window chosen to display BUFFER-OR-NAME or
-nil if no such window is found.
-
-Optional argument NOT-THIS-WINDOW non-nil means display the
-buffer in a window other than the selected one, even if it is
-already displayed in the selected window.
-
-Optional argument FRAME specifies which frames to investigate
-when the specified buffer is already displayed.  If the buffer is
-already displayed in some window on one of these frames simply
-return that window.  Possible values of FRAME are:
-
-`visible' - consider windows on all visible frames on the current
-terminal.
-
-0 - consider windows on all visible or iconified frames on the
-current terminal.
-
-t - consider windows on all frames.
-
-A specific frame - consider windows on that frame only.
-
-nil - consider windows on the selected frame \(actually the
-last non-minibuffer frame\) only.  If, however, either
-`display-buffer-reuse-frames' or `pop-up-frames' is non-nil
-\(non-nil and not graphic-only on a text-only terminal),
-consider all visible or iconified frames on the current terminal."
-  (interactive "BDisplay buffer:\nP")
-  (let* ((can-use-selected-window
-          ;; The selected window is usable unless either NOT-THIS-WINDOW
-          ;; is non-nil, it is dedicated to its buffer, or it is the
-          ;; `minibuffer-window'.
-          (not (or not-this-window
-                   (window-dedicated-p (selected-window))
-                   (window-minibuffer-p))))
-         (buffer (if (bufferp buffer-or-name)
-                     buffer-or-name
-                   (get-buffer buffer-or-name)))
-         (name-of-buffer (buffer-name buffer))
-         ;; On text-only terminals do not pop up a new frame when
-         ;; `pop-up-frames' equals graphic-only.
-         (use-pop-up-frames (if (eq pop-up-frames 'graphic-only)
-                                (display-graphic-p)
-                              pop-up-frames))
-         ;; `frame-to-use' is the frame where to show `buffer' - either
-         ;; the selected frame or the last nonminibuffer frame.
-         (frame-to-use
-          (or (window--frame-usable-p (selected-frame))
-              (window--frame-usable-p (last-nonminibuffer-frame))))
-         ;; `window-to-use' is the window we use for showing `buffer'.
-         window-to-use popped-up-frame)
-    (cond
-     ((not (buffer-live-p buffer))
-      (error "No such buffer %s" buffer))
-     (display-buffer-function
-      ;; Let `display-buffer-function' do the job.
-      (funcall display-buffer-function buffer not-this-window))
-     ((and (not not-this-window)
-           (eq (window-buffer (selected-window)) buffer))
-      ;; The selected window already displays BUFFER and
-      ;; `not-this-window' is nil, so use it.
-      (display-buffer-record-window 'reuse-window (selected-window) buffer)
-      (window--display-buffer-1 (selected-window)))
-     ((and can-use-selected-window (same-window-p name-of-buffer))
-      ;; If the buffer's name tells us to use the selected window do so.
-      (display-buffer-record-window 'reuse-window (selected-window) buffer)
-      (window--display-buffer-2 buffer (selected-window)))
-     ((let ((frames (or frame
-                        (and (or use-pop-up-frames
-                                 display-buffer-reuse-frames
-                                 (not (last-nonminibuffer-frame)))
-                             0)
-                        (last-nonminibuffer-frame))))
-        (setq window-to-use
-              (catch 'found
-                ;; Search frames for a window displaying BUFFER.  Return
-                ;; the selected window only if we are allowed to do so.
-                (dolist (window (get-buffer-window-list buffer 'nomini frames))
-                  (when (or can-use-selected-window
-                            (not (eq (selected-window) window)))
-                    (throw 'found window))))))
-      ;; The buffer is already displayed in some window; use that.
-      (display-buffer-record-window 'reuse-window window-to-use buffer)
-      (window--display-buffer-1 window-to-use))
-     ((and special-display-function
-           ;; `special-display-p' returns either t or a list of frame
-           ;; parameters to pass to `special-display-function'.
-           (let ((pars (special-display-p name-of-buffer)))
-             (when pars
-               (funcall special-display-function
-                        buffer (if (listp pars) pars))))))
-     ((or use-pop-up-frames (not frame-to-use))
-      ;; We want or need a new frame.
-      (setq window-to-use
-            (frame-selected-window (funcall pop-up-frame-function)))
-      (display-buffer-record-window 'pop-up-frame window-to-use buffer)
-      (window--display-buffer-2 buffer window-to-use))
-     ((and pop-up-windows
-           ;; Make a new window.
-           (or (not (frame-parameter frame-to-use 'unsplittable))
-               ;; If the selected frame cannot be split look at
-               ;; `last-nonminibuffer-frame'.
-               (and (eq frame-to-use (selected-frame))
-                    (setq frame-to-use (last-nonminibuffer-frame))
-                    (window--frame-usable-p frame-to-use)
-                    (not (frame-parameter frame-to-use 'unsplittable))))
-           ;; Attempt to split largest or least recently used window.
-           (setq window-to-use
-                 (or (window--try-to-split-window
-                      (get-largest-window frame-to-use t))
-                     (window--try-to-split-window
-                      (get-lru-window frame-to-use t))))
-           (display-buffer-record-window 'pop-up-window window-to-use buffer)
-           (window--display-buffer-2 buffer window-to-use)))
-     ((let ((window-to-undedicate
-             ;; When NOT-THIS-WINDOW is non-nil, temporarily dedicate
-             ;; the selected window to its buffer, to avoid that some of
-             ;; the `get-' routines below choose it.  (Bug#1415)
-             (and not-this-window (not (window-dedicated-p))
-                  (set-window-dedicated-p (selected-window) t)
-                  (selected-window))))
-        (unwind-protect
-            (setq window-to-use
-                  ;; Reuse an existing window.
-                  (or (get-lru-window frame-to-use)
-                      (let ((window (get-buffer-window buffer 'visible)))
-                        (unless (and not-this-window
-                                     (eq window (selected-window)))
-                          window))
-                      (get-largest-window 'visible)
-                      (let ((window (get-buffer-window buffer 0)))
-                        (unless (and not-this-window
-                                     (eq window (selected-window)))
-                          window))
-                      (get-largest-window 0)
-                      (prog1
-                          (frame-selected-window (funcall pop-up-frame-function))
-                        (setq popped-up-frame t))))
-          (when (window-live-p window-to-undedicate)
-            ;; Restore dedicated status of selected window.
-            (set-window-dedicated-p window-to-undedicate nil))))
-      (display-buffer-record-window
-       (if popped-up-frame 'pop-up-frame 'reuse-window) window-to-use buffer)
-      (window--even-window-heights window-to-use)
-      (window--display-buffer-2 buffer window-to-use)))))
-
 (defun window-normalize-buffer-to-display (buffer-or-name)
   "Normalize BUFFER-OR-NAME argument for buffer display functions.
 If BUFFER-OR-NAME is nil, return the curent buffer.  Else, if a
@@ -4641,24 +4492,52 @@ BUFFER-OR-NAME and return that buffer."
     (current-buffer)))
 
 (defvar display-buffer-alist nil
-  "Specifications of user preferences for `display-buffer'.
-This is a list of elements of the form (CONDITION . ACTION) where
-CONDITION is either a regexp matching buffer names, or a function
-that takes a buffer and returns a boolean.  ACTION is a list of
-the form (FUNCTION . ALIST) where FUNCTION can be either a
-function or a list of functions.  Those functions will be called
-with 2 arguments: the buffer to display and an ALIST built from
-the various alists specified in the various ACTIONs.  It should
-either return the window used, or nil to fallback to the next
-function.")
-
-(defvar display-buffer-default-action (list #'display-buffer-default)
-  "Default action to perform to display a buffer.
-This is an ACTION just like in `display-buffer-alist'.")
-
-(defvar display-buffer-overriding-action '(nil)
+  "Alist of conditional actions for `display-buffer'.
+This is a list of elements (CONDITION . ACTION), where:
+
+ CONDITION is either a regexp matching buffer names, or a function
+  that takes a buffer and returns a boolean.
+
+ ACTION is a cons cell (FUNCTION . ALIST), where FUNCTION is
+  either a function or a list of functions.  Each such function
+  should accept 2 arguments: a buffer to display and an alist of
+  the same form as ALIST.  It should return the window used, or
+  nil if it fails to display the window.  See `display-buffer'
+  for more details.
+
+Usable action functions include:
+ `display-buffer-reuse-selected-window'
+ `display-buffer-same-window'
+ `display-buffer-maybe-same-window'
+ `display-buffer-reuse-window'
+ `display-buffer-pop-up-frame'
+ `display-buffer-pop-up-window'
+ `display-buffer-reuse-or-pop-window'
+ `display-buffer-use-some-window'
+
+The above functions recognize the following alist entries:
+ - `inhibit-same-window', if non-nil, prevents the same window
+   from being used for display.
+ - `reuse-frame' specifies the frames that can be searched for a
+   window displaying the buffer.  Its values have the same
+   meaning as the ALL-FRAMES arg to `get-buffer-window-list'.")
+
+(defvar display-buffer-default-action
+  '((display-buffer-reuse-selected-window
+     display-buffer-maybe-same-window
+     display-buffer-reuse-or-pop-window
+     display-buffer-use-some-window
+     ;; If all else fails, pop up a new frame regardless of
+     ;; restrictions.
+     display-buffer-pop-up-frame))
+  "List of default actions for `display-buffer'.
+It should be a cons cell of the form (FUNCTION . ALIST), which
+has the same meaning as in `display-buffer-alist'.")
+
+(defvar display-buffer-overriding-action nil
   "Overriding action to perform to display a buffer.
-This is an ACTION just like in `display-buffer-alist'.")
+If non-nil, it should be a cons cell (FUNCTION . ALIST), which
+has the same meaning as in `display-buffer-alist'.")
 
 (defun display-buffer-assq-regexp (buffer-name alist)
   "Retrieve ALIST entry corresponding to BUFFER-NAME."
@@ -4673,45 +4552,73 @@ This is an ACTION just like in `display-buffer-alist'.")
           (throw 'match (cdr entry)))))))
 
 (defun display-buffer (&optional buffer-or-name action frame)
-  "Display BUFFER in some window."
-  (let* ((buffer (window-normalize-buffer-to-display buffer-or-name))
-         (buffer-name (buffer-name buffer))
-         (user-action
-          (display-buffer-assq-regexp buffer-name display-buffer-alist))
-         (functions
-          (append
-           (list (car display-buffer-overriding-action))
-           (list (car user-action))
-           (and (listp action) (list (car action)))
-           (list (car display-buffer-default-action))))
-         (specifiers (append (cdr display-buffer-overriding-action)
-                             (cdr user-action)
-                             (and (listp action) (cdr action))
-                             (cdr display-buffer-default-action)))
-         function window)
-    (while (and functions (not window))
-      (setq function (car functions))
-      (cond
-       ((listp function)
-        (while (and function (not window))
-          (cond
-           ((eq (car function) 'display-buffer-default)
-            (setq window
-                  (display-buffer-default
-                   buffer (memq action '(t other-window)) frame)))
-           ((functionp (car function))
-            (setq window (funcall (car function) buffer specifiers))))
-          (setq function (cdr function))))
-       ((eq function 'display-buffer-default)
-        (setq window
-              (display-buffer-default
-               buffer (memq action '(t other-window)) frame)))
-       ((functionp function)
-        (setq window
-              (funcall function buffer specifiers))))
-      (setq functions (cdr functions)))
-
-    window))
+  "Display BUFFER-OR-NAME in some window.
+BUFFER-OR-NAME must be a buffer or the name of an existing
+buffer.  Return the window chosen for displaying BUFFER-OR-NAME,
+or nil if no such window is found.
+
+Optional argument ACTION should have the form (FUNCTION . ALIST).
+FUNCTION is either a function or a list of functions.  Each such
+function is called with 2 arguments: the buffer to display and an
+alist.  It should either display the buffer and return the
+window, or return nil if it is unable to display the buffer.
+
+`display-buffer' constructs a list of action functions and an
+action alist by combining `display-buffer-overriding-action',
+`display-buffer-alist', the ACTION argument, and
+`display-buffer-default-action' (in that order).  It calls each
+action function in turn, passing the combined action alist as the
+second argument, until one of the functions returns non-nil.
+
+The ACTION argument to `display-buffer' can also have a non-nil
+and non-list value.  This means to display the buffer in a window
+other than the selected one, even if it is already displayed in
+the selected window.  If called interactively with a prefix
+argument, ACTION is t.
+
+Optional argument FRAME specifies where to look for a window that
+already displays the buffer.  If nil, check only the selected
+frame (actually the last non-minibuffer frame), except if
+`display-buffer-reuse-frames' or `pop-up-frames' is non-nil
+\(non-nil and not graphic-only on a text-only terminal), in which
+case check all visible or iconified frames.  Otherwise, FRAME can
+be a specific frame, `visible' (all visible frames), 0 (all
+frames on the current terminal), or t (all frames)."
+  (interactive "BDisplay buffer:\nP")
+  (let ((buffer (window-normalize-buffer-to-display buffer-or-name))
+        ;; Handle the old form of the first argument.
+        (inhibit-same-window (and action (not (listp action)))))
+    (unless (listp action) (setq action nil))
+    (if display-buffer-function
+        ;; If `display-buffer-function' is defined, let it do the job.
+        (funcall display-buffer-function buffer inhibit-same-window)
+      ;; Otherwise, use the defined actions.
+      (let* ((user-action
+              (display-buffer-assq-regexp (buffer-name buffer)
+                                          display-buffer-alist))
+             ;; Extra actions from the arguments to this function:
+             (extra-action
+              (cons nil (append (if inhibit-same-window
+                                    '((inhibit-same-window . t)))
+                                (if frame
+                                    `((reuse-frame . ,frame))))))
+             ;; Construct action function list and action alist.
+             (actions (list display-buffer-overriding-action
+                            user-action action extra-action
+                            display-buffer-default-action))
+             (functions (apply 'append
+                               (mapcar (lambda (x)
+                                         (setq x (car x))
+                                         (if (listp x) x (list x)))
+                                       actions)))
+             (alist (apply 'append (mapcar 'cdr actions)))
+             window)
+        (unless (buffer-live-p buffer)
+          (error "Invalid buffer"))
+        (while (and functions (not window))
+          (setq window (funcall (car functions) buffer alist)
+                functions (cdr functions)))
+        window))))
 
 (defun display-buffer-other-frame (buffer)
   "Display buffer BUFFER in another frame.
@@ -4736,6 +4643,185 @@ its documentation for additional customization information."
     ;;(make-frame-visible (window-frame old-window))
     ))
 
+;;; `display-buffer' action functions:
+
+(defun display-buffer-reuse-selected-window (buffer alist)
+  "Try to display BUFFER in the selected window if it is already there.
+If this succeeds, return the selected window.
+
+This fails if BUFFER is not displayed in the selected window, or
+if ALIST has a non-nil `inhibit-same-window' entry.  In that
+case, return nil."
+  (when (and (not (cdr (assq 'inhibit-same-window alist)))
+             (eq buffer (window-buffer)))
+    (display-buffer-record-window 'reuse-window (selected-window) buffer)
+    (window--display-buffer-1 (selected-window))))
+
+(defun display-buffer-same-window (buffer alist)
+  "Try to display BUFFER in the selected window.
+If this succeeds, return the selected window.
+
+This fails if the selected window is a minibuffer window or is
+dedicated to another buffer, or if ALIST has a non-nil
+`inhibit-same-window' entry.  In that case, return nil."
+  (unless (or (cdr (assq 'inhibit-same-window alist))
+              (window-minibuffer-p)
+              (window-dedicated-p))
+    (display-buffer-record-window 'reuse-window (selected-window) buffer)
+    (window--display-buffer-2 buffer (selected-window))))
+
+(defun display-buffer-maybe-same-window (buffer alist)
+  "Try to display BUFFER in the selected window.
+This acts like `display-buffer-same-window', except that it also
+fails if `same-window-p' returns nil for this buffer."
+  (and (same-window-p (buffer-name buffer))
+       (display-buffer-same-window buffer alist)))
+
+(defun display-buffer-reuse-window (buffer alist)
+  "Return a window that is already displaying BUFFER.
+If no usable window is found, return nil.
+
+If ALIST has a non-nil `inhibit-same-window' entry, the same
+window cannot be reused.
+
+If ALIST contains a `reuse-frame' entry, that determines the
+frames to check for a window displaying the buffer.  If the entry
+is omitted or the value is nil, check only this frame.  The value
+can also be a specific frame, `visible' (all visible frames),
+0 (all frames on the current terminal), or t (all frames)."
+  (let* ((can-use-selected-window
+          (not (cdr (assq 'inhibit-same-window alist))))
+         (frames (or (cdr (assq 'reuse-frame alist))
+                     (last-nonminibuffer-frame)))
+         (window (catch 'found
+                   (dolist (window (get-buffer-window-list
+                                    buffer 'nomini frames))
+                     (when (or can-use-selected-window
+                               (not (eq (selected-window) window)))
+                       (throw 'found window))))))
+    (when window
+      (display-buffer-record-window 'reuse-window window buffer)
+      (window--display-buffer-1 window))))
+
+(defun display-buffer-pop-up-frame (buffer alist)
+  "Display BUFFER in a new frame.
+This works by calling `pop-up-frame-function'.  If sucessful,
+return the window on the new frame; otherwise return nil."
+  (let ((fun pop-up-frame-function)
+        frame window)
+    (when (and fun
+               (setq frame (funcall fun))
+               (setq window (frame-selected-window frame)))
+      (display-buffer-record-window 'pop-up-frame window buffer)
+      (window--display-buffer-2 buffer window))))
+
+(defun display-buffer-pop-up-window (buffer alist)
+  "Display BUFFER by popping up a new window.
+The new window is created on the selected frame, or in
+`last-nonminibuffer-frame' if no windows can be created there.
+If sucessful, return the new window; otherwise return nil."
+  (let ((frame (or (window--frame-usable-p (selected-frame))
+                   (window--frame-usable-p (last-nonminibuffer-frame))))
+        window)
+    (when (and (or (not (frame-parameter frame 'unsplittable))
+                   ;; If the selected frame cannot be split, look at
+                   ;; `last-nonminibuffer-frame'.
+                   (and (eq frame (selected-frame))
+                        (setq frame (last-nonminibuffer-frame))
+                        (window--frame-usable-p frame)
+                        (not (frame-parameter frame 'unsplittable))))
+               ;; Attempt to split largest or least recently used window.
+               (setq window (or (window--try-to-split-window
+                                 (get-largest-window frame t))
+                                (window--try-to-split-window
+                                 (get-lru-window frame t)))))
+      (display-buffer-record-window 'pop-up-window window buffer)
+      (window--display-buffer-2 buffer window))))
+
+;; This display action function groups together some lower-level ones:
+(defun display-buffer-reuse-or-pop-window (buffer alist)
+  "Display BUFFER in some window other than the selected one.
+This attempts to call the following functions (in order):
+ - `display-buffer-reuse-window', ensuring that it checks all
+   frames on this terminal if `display-buffer-reuse-frames' or
+   `pop-up-frames' is non-nil.
+ - `special-display-function', if it is available.
+ - `display-buffer-pop-up-frame', if specified by `pop-up-frames'.
+ - `display-buffer-pop-up-window', if specified by `pop-up-windows'.
+
+If BUFFER is sucessfully display, return its window; otherwise
+return nil."
+  (let ((use-pop-up-frames (if (eq pop-up-frames 'graphic-only)
+                               (display-graphic-p)
+                             pop-up-frames)))
+    (or (display-buffer-reuse-window
+         buffer
+         ;; If `display-buffer-reuse-frames' or `pop-up-frames' is
+         ;; non-nil, check all frames on this terminal.
+         (if (and (null (cdr (assq 'reuse-frame alist)))
+                  (or use-pop-up-frames display-buffer-reuse-frames))
+             (cons '(reuse-frame . 0) alist)
+           alist))
+        ;; Try with `special-display-function':
+        (and special-display-function
+             ;; `special-display-p' returns either t or a list of frame
+             ;; parameters to pass to `special-display-function'.
+             (let ((pars (special-display-p (buffer-name buffer))))
+               (when pars
+                 (funcall special-display-function
+                          buffer (if (listp pars) pars)))))
+        (and use-pop-up-frames
+             (display-buffer-pop-up-frame buffer alist))
+        (and pop-up-windows
+             (display-buffer-pop-up-window buffer alist)))))
+
+(defun display-buffer-use-some-window (buffer alist)
+  "Display BUFFER in an existing window.
+Search for a usable window, set that window to the buffer, and
+return the window.  If no suitable window is found, return nil."
+  (let* ((not-this-window (cdr (assq 'inhibit-same-window alist)))
+         (window-to-undedicate
+          ;; When NOT-THIS-WINDOW is non-nil, temporarily dedicate the
+          ;; selected window to its buffer, to prevent any of the
+          ;; `get-' routines below from choosing it.  (Bug#1415)
+          (and not-this-window (not (window-dedicated-p))
+               (set-window-dedicated-p (selected-window) t)
+               (selected-window)))
+         (frame (or (window--frame-usable-p (selected-frame))
+                    (window--frame-usable-p (last-nonminibuffer-frame))))
+         (use-pop-up-frames (if (eq pop-up-frames 'graphic-only)
+                                (display-graphic-p)
+                              pop-up-frames))
+         window popped-up-frame)
+    (unwind-protect
+        (setq window
+              ;; Reuse an existing window.
+              (or (get-lru-window frame)
+                  (let ((window (get-buffer-window buffer 'visible)))
+                    (unless (and not-this-window
+                                 (eq window (selected-window)))
+                      window))
+                  (get-largest-window 'visible)
+                  (let ((window (get-buffer-window buffer 0)))
+                    (unless (and not-this-window
+                                 (eq window (selected-window)))
+                      window))
+                  (get-largest-window 0)
+                  (and use-pop-up-frames
+                       (prog1
+                           (frame-selected-window (funcall pop-up-frame-function))
+                         (setq popped-up-frame t)))))
+      (when (window-live-p window-to-undedicate)
+        ;; Restore dedicated status of selected window.
+        (set-window-dedicated-p window-to-undedicate nil)))
+    (when window
+      (display-buffer-record-window
+       (if popped-up-frame 'pop-up-frame 'reuse-window) window buffer)
+      (window--even-window-heights window)
+      (window--display-buffer-2 buffer window))))
+
+;;; Display + selection commands:
+
 (defun pop-to-buffer (buffer-or-name &optional other-window norecord)
   "Select buffer BUFFER-OR-NAME in some window, preferably a different one.
 BUFFER-OR-NAME may be a buffer, a string \(a buffer name), or
@@ -4759,20 +4845,7 @@ of `display-buffer' for additional customization information.
 Optional third arg NORECORD non-nil means do not put this buffer
 at the front of the list of recently selected ones."
   (interactive "BPop to buffer:\nP")
-  (let ((buffer (window-normalize-buffer-to-display buffer-or-name))
-        (old-window (selected-window))
-        (old-frame (selected-frame))
-        new-window new-frame)
-    (set-buffer buffer)
-    (setq new-window (display-buffer buffer other-window))
-    (setq new-frame (window-frame new-window))
-    (if (eq old-frame new-frame)
-        ;; Make sure new-window gets selected (Bug#8615), (Bug#6954).
-        (select-window new-window norecord)
-      ;; `display-buffer' has chosen another frame, make sure it gets
-      ;; input focus and is risen.
-      (select-frame-set-input-focus new-frame norecord))
-    buffer))
+  (pop-to-buffer-1 buffer-or-name (if other-window t nil) norecord))
 
 (defun pop-to-buffer-same-window (&optional buffer-or-name norecord)
   "Pop to buffer specified by BUFFER-OR-NAME in the selected window.
@@ -4781,40 +4854,38 @@ the selected window, usually because it is dedicated to another
 buffer.  Optional arguments BUFFER-OR-NAME and NORECORD are as
 for `pop-to-buffer'."
   (interactive "BPop to buffer in selected window:\nP")
-  (let ((buffer (window-normalize-buffer-to-display buffer-or-name)))
-    (cond
-     ((eq buffer (window-buffer))
-      (unless norecord
-        (select-window (selected-window)))
-      (set-buffer buffer))
-     ((or (window-minibuffer-p) (window-dedicated-p))
-      (pop-to-buffer buffer norecord))
-     (t
-      (set-window-buffer nil buffer)
-      (unless norecord
-        (select-window (selected-window)))
-      (set-buffer buffer)))))
-
-(defun pop-to-buffer-other-window (&optional buffer-or-name norecord)
-  "Pop to buffer specified by BUFFER-OR-NAME in another window.
-The selected window will be used only if there is no other
-choice.  Windows on the selected frame are preferred to windows
-on other frames.  Optional arguments BUFFER-OR-NAME and NORECORD
-are as for `pop-to-buffer'."
-  (interactive "BPop to buffer in another window:\nP")
-  (let ((pop-up-windows t)
-        same-window-buffer-names same-window-regexps)
-    (pop-to-buffer buffer-or-name t norecord)))
-
-(defun pop-to-buffer-other-frame (&optional buffer-or-name norecord)
-  "Pop to buffer specified by BUFFER-OR-NAME on another frame.
-The selected frame will be used only if there's no other choice.
-Optional arguments BUFFER-OR-NAME and NORECORD are as for
-`pop-to-buffer'."
-  (interactive "BPop to buffer on another frame:\nP")
-  (let ((pop-up-frames t)
-        same-window-buffer-names same-window-regexps)
-    (pop-to-buffer buffer-or-name t norecord)))
+  (pop-to-buffer-1 buffer-or-name 'same-window norecord))
+
+(defun pop-to-buffer-1 (buffer-or-name window-choice norecord)
+  (set-buffer (window-normalize-buffer-to-display
+               ;; BUFFER-OR-NAME nil means another buffer.
+               (or buffer-or-name
+                   (other-buffer (current-buffer)))))
+  (let ((old-window (selected-window))
+        (old-frame (selected-frame))
+        (same-window-buffer-names same-window-buffer-names)
+        (same-window-regexps same-window-regexps))
+    (if (eq window-choice t)
+        (setq same-window-buffer-names nil
+              same-window-regexps nil))
+    (let* ((action
+            ;; Based on the WINDOW-CHOICE argument, choose an action
+            ;; argument to pass to `display-buffer'.
+            (cond
+             ((eq window-choice 'same-window)
+              '((display-buffer-reuse-selected-window
+                 display-buffer-same-window)))
+             (window-choice
+              '(nil (inhibit-same-window . t)))))
+           (window (display-buffer (current-buffer) action))
+           (frame (window-frame window)))
+      (if (eq frame old-frame)
+          ;; Make sure new window gets selected (Bug#8615), (Bug#6954).
+          (select-window window norecord)
+        ;; If `display-buffer' has chosen another frame, make sure it
+        ;; gets input focus.
+        (select-frame-set-input-focus frame norecord))
+      (current-buffer))))
 
 (defun read-buffer-to-switch (prompt)
   "Read the name of a buffer to switch to, prompting with PROMPT.