Rewrite display-buffer-alist and display-buffer-normalize-specifiers.

* window.el (display-buffer-alist): Set pop-up-window-min-height
and pop-up-window-min-width in default value.  Reported by
Thierry Volpiatto <thierry.volpiatto@gmail.com>.  New specifier
other-window-means-other-frame.
(display-buffer-macro-specifiers): Comment out entry for
other-window specifier.
(display-buffer-other-window-means-other-frame): New function.
(display-buffer-normalize-specifiers-1): New arguments
buffer-name and label.  Treat other-window case specially.
(display-buffer-normalize-specifiers-2): Treat other-window case
specially.
(display-buffer-normalize-specifiers-3): New function.
(display-buffer-normalize-specifiers): Call
display-buffer-normalize-specifiers-3.

lisp/ChangeLog

+2011-06-17  Martin Rudalics  <rudalics@gmx.at>
+
+	* window.el (display-buffer-alist): Set pop-up-window-min-height
+	and pop-up-window-min-width in default value.  Reported by
+	Thierry Volpiatto <thierry.volpiatto@gmail.com>.  New specifier
+	other-window-means-other-frame.
+	(display-buffer-macro-specifiers): Comment out entry for
+	other-window specifier.
+	(display-buffer-other-window-means-other-frame): New function.
+	(display-buffer-normalize-specifiers-1): New arguments
+	buffer-name and label.  Treat other-window case specially.
+	(display-buffer-normalize-specifiers-2): Treat other-window case
+	specially.
+	(display-buffer-normalize-specifiers-3): New function.
+	(display-buffer-normalize-specifiers): Call
+	display-buffer-normalize-specifiers-3.
+
 2011-06-17  Martin Rudalics  <rudalics@gmx.at>
 
 	* window.el (same-window-p): Fix two typos introduced when
@@ -11,6 +28,8 @@
 	Suggested by David Engster <deng@randomsample.de>.
 	(even-window-heights): Initialize to 'unset.
 	(display-buffer-alist-set): Handle new 'unset initializations.
+	(display-buffer-macro-specifiers): Don't pop up a new frame in the
+	other window case.
 
 2011-06-16  Martin Rudalics  <rudalics@gmx.at>
 

lisp/window.el

@@ -3500,12 +3500,11 @@ buffer display specifiers.")
      (reuse-window nil same nil)
      (pop-up-window (largest . nil) (lru . nil))
      (reuse-window nil other nil))
-    (other-window
-     ;; Avoid selected window.
-     (reuse-window other same visible)
-     (pop-up-window (largest . nil) (lru . nil))
-     (pop-up-frame)
-     (reuse-window other other visible))
+    ;; (other-window
+    ;;  ;; Avoid selected window.
+    ;;  (reuse-window other same visible)
+    ;;  (pop-up-window (largest . nil) (lru . nil))
+    ;;  (reuse-window other other visible))
     (same-frame-other-window
      ;; Avoid other frames and selected window.
      (reuse-window other same nil)
@@ -3523,10 +3522,16 @@ buffer display specifiers.")
 
 (defcustom display-buffer-alist
   '((((regexp . ".*"))
+     ;; Reuse window showing same buffer.
      reuse-window (reuse-window nil same visible)
+     ;; Pop up window.
      pop-up-window
+     ;; Split largest or lru window.
      (pop-up-window (largest . nil) (lru . nil))
-     reuse-window (reuse-window other other nil)
+     (pop-up-window-min-height . 40) ; split-height-threshold / 2
+     (pop-up-window-min-width . 80) ; split-width-threshold / 2
+     ;; Reuse any but selected window on same frame.
+     reuse-window (reuse-window other nil nil)
      (reuse-window-even-sizes . t)))
   "List associating buffer identifiers with display specifiers.
 The car of each element of this list is built from a set of cons
@@ -4231,6 +4236,15 @@ using the location specifiers `same-window' or `other-frame'."
 	:format "%[No other window%] %v\n" :size 15
 	(const :tag "Off" :format "%t" nil)
 	(const :tag "Ignore" :format "%t" t)))
+      ;; Other window means other frame.
+      (cons
+       :format "%v"
+       (const :format "" other-window-means-other-frame)
+       (choice
+	:help-echo "Whether other window means same or other frame."
+	:format "%[Same or other frame%] %v\n" :size 15
+	(const :tag "Same frame" :format "%t" nil)
+	(const :tag "Other frame" :format "%t" t)))
       ;; Overriding.
       (cons
        :format "%v\n"
@@ -4915,6 +4929,26 @@ SPECIFIERS must be a list of buffer display specifiers."
 	  (set-window-parameter window 'window-slot slot))
 	(display-buffer-in-window buffer window specifiers)))))
 
+(defun display-buffer-other-window-means-other-frame (buffer-or-name &optional label)
+  "Return non-nil if BUFFER shall be preferably displayed in another frame.
+BUFFER must be a live buffer or the name of a live buffer.
+
+Return nil if BUFFER shall be preferably displayed in another
+window on the selected frame.  Return non-nil if BUFFER shall be
+preferably displayed in a window on any but the selected frame.
+
+Optional argument LABEL is like the same argument of
+`display-buffer'.
+
+The calculation of the return value is exclusively based on the
+user preferences expressed in `display-buffer-alist'."
+  (let* ((buffer (normalize-live-buffer buffer-or-name))
+	 (list (display-buffer-normalize-specifiers-3
+		(buffer-name buffer) label))
+	 (value (assq 'other-window-means-other-frame
+		      (or (car list) (cdr list)))))
+    (when value (cdr value))))
+
 (defun 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
@@ -4928,9 +4962,11 @@ BUFFER-OR-NAME and return that buffer."
 	    buffer))
     (current-buffer)))
 
-(defun display-buffer-normalize-specifiers-1 (specifiers)
+(defun display-buffer-normalize-specifiers-1 (specifiers buffer-name label)
   "Subroutine of `display-buffer-normalize-specifiers'.
-SPECIFIERS is the SPECIFIERS argument of `display-buffer'."
+SPECIFIERS is a list of buffer display specfiers.  BUFFER-NAME is
+the name of the buffer that shall be displayed, LABEL the same
+argument of `display-buffer'."
   (let (normalized entry)
     (cond
      ((not specifiers)
@@ -4941,6 +4977,14 @@ SPECIFIERS is the SPECIFIERS argument of `display-buffer'."
 	(cond
 	 ((consp specifier)
 	  (setq normalized (cons specifier normalized)))
+	 ((eq specifier 'other-window)
+	  ;; `other-window' must be treated separately.
+	  (let* ((other-frame (display-buffer-other-window-means-other-frame
+			       buffer-name label))
+		 (entry (assq (if other-frame 'other-frame 'other-window)
+			      display-buffer-macro-specifiers)))
+	    (dolist (item (cdr entry))
+	      (setq normalized (cons item normalized)))))
 	 ((symbolp specifier)
 	  ;; Might be a macro specifier, try to expand it (the cdr is a
 	  ;; list and we have to reverse it later, so do it one at a
@@ -4950,16 +4994,15 @@ SPECIFIERS is the SPECIFIERS argument of `display-buffer'."
 	      (setq normalized (cons item normalized)))))))
       ;; Reverse list.
       (nreverse normalized))
-     ((and (not (eq specifiers 'other-window))
-	   (setq entry (assq specifiers display-buffer-macro-specifiers)))
+     ((setq entry (assq specifiers display-buffer-macro-specifiers))
       ;; A macro specifier.
       (cdr entry))
-     ((with-no-warnings (not pop-up-frames))
-      ;; Pop up a new window.
-      (cdr (assq 'other-window display-buffer-macro-specifiers)))
+     ((or (display-buffer-other-window-means-other-frame buffer-name label)
+	  (with-no-warnings (not pop-up-frames)))
+      (cdr (assq 'other-frame display-buffer-macro-specifiers)))
      (t
-      ;; Pop up a new frame.
-      (cdr (assq 'other-frame display-buffer-macro-specifiers))))))
+      ;; In any other case pop up a new window.
+      (cdr (assq 'same-frame-other-window display-buffer-macro-specifiers))))))
 
 (defun display-buffer-normalize-specifiers-2 (&optional buffer-or-name)
   "Subroutine of `display-buffer-normalize-specifiers'.
@@ -5064,27 +5107,8 @@ options."
 
       specifiers)))
 
-(defun display-buffer-normalize-specifiers (buffer-name specifiers label)
-  "Return normalized specifiers for a buffer matching BUFFER-NAME or LABEL.
-BUFFER-NAME must be a string specifying a valid buffer name.
-SPECIFIERS and LABEL are the homonymous arguments of
-`display-buffer'.
-
-The method for displaying the buffer specified by BUFFER-NAME or
-LABEL is established by appending the following four lists of
-specifiers:
-
-- The specifiers in `display-buffer-alist' whose buffer
-  identifier matches BUFFER-NAME or LABEL and whose 'override
-  component is set.
-
-- SPECIFIERS.
-
-- The specifiers in `display-buffer-alist' whose buffer
-  identifier matches BUFFER-NAME or LABEL and whose 'override
-  component is not set.
-
-- `display-buffer-default-specifiers'."
+(defun display-buffer-normalize-specifiers-3 (buffer-name label)
+  "Subroutine of `display-buffer-normalize-specifiers'."
   (let (list-1 list-2)
     (dolist (entry display-buffer-alist)
       (when (and (listp entry)
@@ -5100,7 +5124,8 @@ specifiers:
 				   (and (eq type 'label) (eq value label)))
 			   (throw 'match t)))))))
 	(let* ((raw (cdr entry))
-	       (normalized (display-buffer-normalize-specifiers-1 raw)))
+	       (normalized
+		(display-buffer-normalize-specifiers-1 raw buffer-name label)))
 	  (if (assq 'override raw)
 	      (setq list-1
 		    (if list-1
@@ -5111,15 +5136,39 @@ specifiers:
 		      (append list-2 normalized)
 		    normalized))))))
 
+    (cons list-1 list-2)))
+
+(defun display-buffer-normalize-specifiers (buffer-name specifiers label)
+  "Return normalized specifiers for a buffer matching BUFFER-NAME or LABEL.
+BUFFER-NAME must be a string specifying a valid buffer name.
+SPECIFIERS and LABEL are the homonymous arguments of
+`display-buffer'.
+
+The method for displaying the buffer specified by BUFFER-NAME or
+LABEL is established by appending the following four lists of
+specifiers:
+
+- The specifiers in `display-buffer-alist' whose buffer
+  identifier matches BUFFER-NAME or LABEL and whose 'override
+  component is set.
+
+- SPECIFIERS.
+
+- The specifiers in `display-buffer-alist' whose buffer
+  identifier matches BUFFER-NAME or LABEL and whose 'override
+  component is not set.
+
+- `display-buffer-default-specifiers'."
+  (let* ((list (display-buffer-normalize-specifiers-3 buffer-name label)))
     (append
      ;; Overriding user specifiers.
-     list-1
+     (car list)
      ;; Application specifiers.
-     (display-buffer-normalize-specifiers-1 specifiers)
+     (display-buffer-normalize-specifiers-1 specifiers buffer-name label)
      ;; Emacs 23 compatibility specifiers.
      (display-buffer-normalize-specifiers-2 buffer-name)
      ;; Non-overriding user specifiers.
-     list-2
+     (cdr list)
      ;; Default specifiers.
      display-buffer-default-specifiers)))