Rewrite window-resizable.

* window.el (window-size-fixed-p): Rewrite doc-string.
(window-resizable-p): Rename to window--resizable-p.  Update
callers.
(window--resizable): New function.  Make all callers of
window-resizable call window--resizable instead.
(window-resizable): Rewrite in terms of window--resizable.
* windows.texi (Resizing Windows): Rewrite documentation of
window-resizable.

4 files changed, 71 insertions, 36 deletions

diff --git a/doc/lispref/ChangeLog b/doc/lispref/ChangeLog
index 2b1e210fc73..cbe016ac96d 100644
--- a/doc/lispref/ChangeLog
+++ b/doc/lispref/ChangeLog
@@ -1,3 +1,8 @@
+2011-11-09  Martin Rudalics  <rudalics@gmx.at>
+
+        * windows.texi (Resizing Windows): Rewrite documentation of
+        window-resizable.
+
 2011-11-09  Chong Yidong  <cyd@gnu.org>
 
         * windows.texi (Splitting Windows): Simplify example.
diff --git a/doc/lispref/windows.texi b/doc/lispref/windows.texi
index 17483d4c0ed..52ac5a53900 100644
--- a/doc/lispref/windows.texi
+++ b/doc/lispref/windows.texi
@@ -553,7 +553,7 @@ changed except by resizing the frame (@pxref{Size and Position}).
 arguments.  Resizing an internal window causes its child windows to be
 resized to fit the same space.
 
-@defun window-resizable window delta &optional horizontal ignore side noup nodown
+@defun window-resizable window delta &optional horizontal ignore
 This function returns @var{delta} if the size of @var{window} can be
 changed vertically by @var{delta} lines.  If the optional argument
 @var{horizontal} is non-@code{nil}, it instead returns @var{delta} if
@@ -562,10 +562,11 @@ does not actually change the window size.
 
 If @var{window} is @code{nil}, it defaults to the selected window.
 
-A positive value of @var{delta} enlarges the window by that number of
-lines or columns; a negative value of @var{delta} shrinks it.  If
-@var{delta} is non-zero, a return value of 0 means that the window
-cannot be resized.
+A positive value of @var{delta} means to check whether the window can be
+enlarged by that number of lines or columns; a negative value of
+@var{delta} means to check whether the window can be shrunk by that many
+lines or columns.  If @var{delta} is non-zero, a return value of 0 means
+that the window cannot be resized.
 
 Normally, the variables @code{window-min-height} and
 @code{window-min-width} specify the smallest allowable window size.
@@ -577,12 +578,6 @@ Instead, it considers the minimum-height window to be one consisting
 of a header (if any), a mode line, plus a text area one line tall; and
 a minimum-width window as one consisting of fringes, margins, and
 scroll bar (if any), plus a text area two columns wide.
-
-If the optional argument @var{noup} is non-@code{nil}, this function
-considers a resize operation that does not alter the window parent of
-@var{window}, only its siblings.  If the optional argument
-@var{nodown} is non-@code{nil}, it does not attempt to check whether
-@var{window} itself and its child windows can be resized.
 @end defun
 
 @defun window-resize window delta &optional horizontal ignore
diff --git a/lisp/ChangeLog b/lisp/ChangeLog
index b1039c77243..d0a50366eff 100644
--- a/lisp/ChangeLog
+++ b/lisp/ChangeLog
@@ -1,3 +1,12 @@
+2011-11-09  Martin Rudalics  <rudalics@gmx.at>
+
+        * window.el (window-size-fixed-p): Rewrite doc-string.
+        (window-resizable-p): Rename to window--resizable-p.  Update
+        callers.
+        (window--resizable): New function.  Make all callers of
+        window-resizable call window--resizable instead.
+        (window-resizable): Rewrite in terms of window--resizable.
+
 2011-11-08  Glenn Morris  <rgm@gnu.org>
 
         * progmodes/delphi.el (delphi-mode-syntax-table):
diff --git a/lisp/window.el b/lisp/window.el
index 1e95a647b1f..ecd4a62b093 100644
--- a/lisp/window.el
+++ b/lisp/window.el
@@ -704,8 +704,8 @@ window.  Optional argument HORIZONTAL non-nil means return
 non-nil if WINDOW's width is fixed.
 
 If this function returns nil, this does not necessarily mean that
-WINDOW can be resized in the desired direction.  The functions
-`window-resizable' and `window-resizable-p' will tell that."
+WINDOW can be resized in the desired direction.  The function
+`window-resizable' can tell that."
   (window-size-fixed-1
    (window-normalize-window window) horizontal))
 
@@ -865,14 +865,14 @@ only whether other windows can be shrunk appropriately."
     (window-max-delta-1 window 0 horizontal ignore trail noup)))
 
 ;; Make NOUP also inhibit the min-size check.
-(defun window-resizable (window delta &optional horizontal ignore trail noup nodown)
+(defun window--resizable (window delta &optional horizontal ignore trail noup nodown)
   "Return DELTA if WINDOW can be resized vertically by DELTA lines.
 Optional argument HORIZONTAL non-nil means return DELTA if WINDOW
 can be resized horizontally by DELTA columns.  A return value of
 zero means that WINDOW is not resizable.
 
 DELTA positive means WINDOW shall be enlarged by DELTA lines or
-columns.  If WINDOW cannot be enlarged by DELTA lines or columns
+columns.  If WINDOW cannot be enlarged by DELTA lines or columns,
 return the maximum value in the range 0..DELTA by which WINDOW
 can be enlarged.
 
@@ -894,11 +894,12 @@ of or below WINDOW can be shrunk.  Optional argument TRAIL
 shrunk.
 
 Optional argument NOUP non-nil means don't go up in the window
-tree but try to distribute the space among the other windows
-within WINDOW's combination.
+tree but check only whether space can be obtained from (or given
+to) WINDOW's siblings.
 
-Optional argument NODOWN non-nil means don't check whether WINDOW
-and its child windows can be resized."
+Optional argument NODOWN non-nil means don't go down in the
+window tree.  This means do not check whether resizing would
+violate size restrictions of WINDOW or its child windows."
   (setq window (window-normalize-window window))
   (cond
    ((< delta 0)
@@ -909,17 +910,42 @@ and its child windows can be resized."
          delta))
    (t 0)))
 
-(defun window-resizable-p (window delta &optional horizontal ignore trail noup nodown)
+(defun window--resizable-p (window delta &optional horizontal ignore trail noup nodown)
   "Return t if WINDOW can be resized vertically by DELTA lines.
 For the meaning of the arguments of this function see the
-doc-string of `window-resizable'."
+doc-string of `window--resizable'."
   (setq window (window-normalize-window window))
   (if (> delta 0)
-      (>= (window-resizable window delta horizontal ignore trail noup nodown)
+      (>= (window--resizable window delta horizontal ignore trail noup nodown)
           delta)
-    (<= (window-resizable window delta horizontal ignore trail noup nodown)
+    (<= (window--resizable window delta horizontal ignore trail noup nodown)
         delta)))
 
+(defun window-resizable (window delta &optional horizontal ignore)
+  "Return DELTA if WINDOW can be resized vertically by DELTA lines.
+Optional argument HORIZONTAL non-nil means return DELTA if WINDOW
+can be resized horizontally by DELTA columns.  A return value of
+zero means that WINDOW is not resizable.
+
+DELTA positive means WINDOW shall be enlarged by DELTA lines or
+columns.  If WINDOW cannot be enlarged by DELTA lines or columns
+return the maximum value in the range 0..DELTA by which WINDOW
+can be enlarged.
+
+DELTA negative means WINDOW shall be shrunk by -DELTA lines or
+columns.  If WINDOW cannot be shrunk by -DELTA lines or columns,
+return the minimum value in the range DELTA..0 that can be used
+for shrinking WINDOW.
+
+Optional argument IGNORE non-nil means ignore any restrictions
+imposed by fixed size windows, `window-min-height' or
+`window-min-width' settings.  IGNORE a window means ignore
+restrictions for that window only.  IGNORE equal `safe' means
+live windows may get as small as `window-safe-min-height' lines
+and `window-safe-min-width' columns."
+  (setq window (window-normalize-window window))
+  (window--resizable window delta horizontal ignore))
+
 (defun window-total-size (&optional window horizontal)
   "Return the total height or width of window WINDOW.
 If WINDOW is omitted or nil, it defaults to the selected window.
@@ -1475,7 +1501,7 @@ instead."
       (error "Cannot resize the root window of a frame"))
      ((window-minibuffer-p window)
       (window--resize-mini-window window delta))
-     ((window-resizable-p window delta horizontal ignore)
+     ((window--resizable-p window delta horizontal ignore)
       (window--resize-reset frame horizontal)
       (window--resize-this-window window delta horizontal ignore t)
       (if (and (not (window-splits window))
@@ -1829,7 +1855,7 @@ preferably only resize windows adjacent to EDGE."
             ;; Set this-delta to what we can get from WINDOW's siblings.
             (if (= (- delta) (window-total-size window horizontal))
                 ;; A deletion, presumably.  We must handle this case
-                ;; specially since `window-resizable' can't be used.
+                ;; specially since `window--resizable' can't be used.
                 (if this-delta
                     ;; There's at least one resizable sibling we can
                     ;; give WINDOW's size to.
@@ -1838,7 +1864,7 @@ preferably only resize windows adjacent to EDGE."
                   (setq this-delta 0))
               ;; Any other form of resizing.
               (setq this-delta
-                    (window-resizable window delta horizontal ignore trail t)))
+                    (window--resizable window delta horizontal ignore trail t)))
 
             ;; Set other-delta to what we still have to get from
             ;; ancestor windows of parent.
@@ -1904,7 +1930,7 @@ resize only windows on the left or above EDGE.  If TRAIL equals
 preferably only resize windows adjacent to EDGE.
 
 This function recursively resizes WINDOW's child windows to fit the
-new size.  Make sure that WINDOW is `window-resizable' before
+new size.  Make sure that WINDOW is `window--resizable' before
 calling this function.  Note that this function does not resize
 siblings of WINDOW or WINDOW's parent window.  You have to
 eventually call `window-resize-apply' in order to make resizing
@@ -2044,7 +2070,7 @@ move it as far as possible in the desired direction."
           ;; Start resizing.
           (window--resize-reset frame horizontal)
           ;; Try to enlarge LEFT first.
-          (setq this-delta (window-resizable left delta horizontal))
+          (setq this-delta (window--resizable left delta horizontal))
           (unless (zerop this-delta)
             (window--resize-this-window
              left this-delta horizontal nil t 'before
@@ -2067,7 +2093,7 @@ move it as far as possible in the desired direction."
           ;; Start resizing.
           (window--resize-reset frame horizontal)
           ;; Try to enlarge RIGHT.
-          (setq this-delta (window-resizable right (- delta) horizontal))
+          (setq this-delta (window--resizable right (- delta) horizontal))
           (unless (zerop this-delta)
             (window--resize-this-window
              right this-delta horizontal nil t 'after
@@ -2098,7 +2124,7 @@ Return nil."
    ((zerop delta))
    ((window-size-fixed-p nil horizontal)
     (error "Selected window has fixed size"))
-   ((window-resizable-p nil delta horizontal)
+   ((window--resizable-p nil delta horizontal)
     (window-resize nil delta horizontal))
    (t
     (window-resize
@@ -2119,7 +2145,7 @@ Return nil."
    ((zerop delta))
    ((window-size-fixed-p nil horizontal)
     (error "Selected window has fixed size"))
-   ((window-resizable-p nil (- delta) horizontal)
+   ((window--resizable-p nil (- delta) horizontal)
     (window-resize nil (- delta) horizontal))
    (t
     (window-resize
@@ -2392,7 +2418,7 @@ non-side window, signal an error."
           (set-window-new-normal
            sibling (+ (window-normal-size sibling horizontal)
                       (window-normal-size window horizontal))))
-         ((window-resizable-p window (- size) horizontal nil nil nil t)
+         ((window--resizable-p window (- size) horizontal nil nil nil t)
           ;; Can do without resizing fixed-size windows.
           (window--resize-siblings window (- size) horizontal))
          (t
@@ -3763,13 +3789,13 @@ value can be also stored on disk and read back in a new session."
               (let ((delta (- (cdr (assq 'total-height item))
                               (window-total-height window)))
                     window-size-fixed)
-                (when (window-resizable-p window delta)
+                (when (window--resizable-p window delta)
                   (window-resize window delta)))
             ;; Else check whether the window is not high enough.
             (let* ((min-size (window-min-size window nil ignore))
                    (delta (- min-size (window-total-size window))))
               (when (and (> delta 0)
-                         (window-resizable-p window delta nil ignore))
+                         (window--resizable-p window delta nil ignore))
                 (window-resize window delta nil ignore))))
           ;; Adjust horizontally.
           (if (memq window-size-fixed '(t width))
@@ -3777,13 +3803,13 @@ value can be also stored on disk and read back in a new session."
               (let ((delta (- (cdr (assq 'total-width item))
                               (window-total-width window)))
                     window-size-fixed)
-                (when (window-resizable-p window delta)
+                (when (window--resizable-p window delta)
                   (window-resize window delta)))
             ;; Else check whether the window is not wide enough.
             (let* ((min-size (window-min-size window t ignore))
                    (delta (- min-size (window-total-size window t))))
               (when (and (> delta 0)
-                         (window-resizable-p window delta t ignore))
+                         (window--resizable-p window delta t ignore))
                 (window-resize window delta t ignore))))
           ;; Set dedicated status.
           (set-window-dedicated-p window (cdr (assq 'dedicated state)))