bug#1488: 23.0.60; dired-pop-to-buffer: use fit-window-to-buffer

[martin rudalics]

Stephen,

`fit-window-to-buffer' had more bugs than I thought.  I rewrote it
completely but you would have to use it for a couple of days to know
whether it DTRT.  Patch attached.

martin

*** window.el.~1.169.~  2008-11-27 11:14:14.671875000 +0100
--- window.el   2008-12-06 20:20:34.390625000 +0100
***************
*** 1296,1379 ****
    "Adjust height of WINDOW to display its buffer's contents exactly.
  WINDOW defaults to the selected window.
  Optional argument MAX-HEIGHT specifies the maximum height of the
! window and defaults to the height of WINDOW's frame.
  Optional argument MIN-HEIGHT specifies the minimum height of the
  window and defaults to `window-min-height'.
  Both, MAX-HEIGHT and MIN-HEIGHT are specified in lines and
  include the mode line and header line, if any.
  Always return nil."
    (interactive)
! 
!   (when (null window)
!     (setq window (selected-window)))
!   (when (null max-height)
!     (setq max-height (frame-height (window-frame window))))
! 
!   (let* ((buf
!         ;; Buffer that is displayed in WINDOW
!         (window-buffer window))
!        (window-height
!         ;; The current height of WINDOW
!         (window-height window))
!        (desired-height
!         ;; The height necessary to show the buffer displayed by WINDOW
!         ;; (`count-screen-lines' always works on the current buffer).
!         (with-current-buffer buf
!           (+ (count-screen-lines)
!              ;; If the buffer is empty, (count-screen-lines) is
!              ;; zero.  But, even in that case, we need one text line
!              ;; for cursor.
!              (if (= (point-min) (point-max))
!                  1 0)
!              ;; For non-minibuffers, count the mode-line, if any
!              (if (and (not (window-minibuffer-p window))
!                       mode-line-format)
!                  1 0)
!              ;; Count the header-line, if any
!              (if header-line-format 1 0))))
!        (delta
!         ;; Calculate how much the window height has to change to show
!         ;; desired-height lines, constrained by MIN-HEIGHT and MAX-HEIGHT.
!         (- (max (min desired-height max-height)
!                 (or min-height window-min-height))
!            window-height)))
! 
!     ;; Don't try to redisplay with the cursor at the end
!     ;; on its own line--that would force a scroll and spoil things.
!     (when (with-current-buffer buf
!           (and (eobp) (bolp) (not (bobp))))
!       (set-window-point window (1- (window-point window))))
! 
!     (save-selected-window
!       (select-window window 'norecord)
! 
!       ;; Adjust WINDOW to the nominally correct size (which may actually
!       ;; be slightly off because of variable height text, etc).
!       (unless (zerop delta)
!       (enlarge-window delta))
! 
!       ;; Check if the last line is surely fully visible.  If not,
!       ;; enlarge the window.
!       (let ((end (with-current-buffer buf
!                  (save-excursion
!                    (goto-char (point-max))
!                    (when (and (bolp) (not (bobp)))
!                      ;; Don't include final newline
!                      (backward-char 1))
!                    (when truncate-lines
!                      ;; If line-wrapping is turned off, test the
!                      ;; beginning of the last line for visibility
!                      ;; instead of the end, as the end of the line
!                      ;; could be invisible by virtue of extending past
!                      ;; the edge of the window.
!                      (forward-line 0))
!                    (point)))))
!       (set-window-vscroll window 0)
!       (while (and (< desired-height max-height)
!                   (= desired-height (window-height window))
!                   (not (pos-visible-in-window-p end window)))
!         (enlarge-window 1)
!         (setq desired-height (1+ desired-height)))))))
  
  (defun window-safely-shrinkable-p (&optional window)
    "Return t if WINDOW can be shrunk without shrinking other windows.
--- 1296,1383 ----
    "Adjust height of WINDOW to display its buffer's contents exactly.
  WINDOW defaults to the selected window.
  Optional argument MAX-HEIGHT specifies the maximum height of the
! window and defaults to the maximum permissible height of a window
! on WINDOW's frame.
  Optional argument MIN-HEIGHT specifies the minimum height of the
  window and defaults to `window-min-height'.
  Both, MAX-HEIGHT and MIN-HEIGHT are specified in lines and
  include the mode line and header line, if any.
  Always return nil."
    (interactive)
!   ;; Do all the work in WINDOW and its buffer and restore the selected
!   ;; window and the current buffer when we're done.
!   (save-excursion
!     (with-selected-window (or window (selected-window))
!       (set-buffer (window-buffer))
!       (let* ((desired-height
!             ;; The height necessary to show all of WINDOW's buffer.
!             ;; For an empty buffer (count-screen-lines) returns zero.
!             ;; Even in that case we need one line for the cursor.
!             (+ (max (count-screen-lines) 1)
!                ;; For non-minibuffers count the mode-line, if any.
!                (if (and (not (window-minibuffer-p)) mode-line-format) 1 0)
!                ;; Count the header-line, if any.
!                (if header-line-format 1 0)))
!            ;; MIN-HEIGHT must not be less than 1 and defaults to
!            ;; `window-min-height'.
!            (min-height (max (or min-height window-min-height) 1))
!            (max-window-height
!             ;; Maximum height of any window on this frame.
!             (min (window-height (frame-root-window)) (frame-height)))
!            ;; MAX-HEIGHT must not be larger than max-window-height and
!            ;; also defaults to that value.
!            (max-height
!             (min (or max-height max-window-height) max-window-height))
!            (delta
!             ;; How much the window height has to change to show
!             ;; desired-height lines, constrained by MIN-HEIGHT and
!             ;; MAX-HEIGHT.
!             (- (min max-height (max desired-height min-height))
!                (window-height)))
!            ;; Avoid deleting this window if it becomes too small.  As
!            ;; a side-effect, this may keep some other windows as well.
! 
!            ;; Note: The following was removed by Jan on 2007-07-09 but
!            ;; it seems needed to (1) avoid deleting the window we want
!            ;; to shrink, and (2) as a consequence of (1) have
!            ;; (window-height WINDOW) return the buffer displayed by
!            ;; WINDOW which seems like a bug in delete_all_subwindows
!            ;; which uses decode_any_window (so it doesn't care wether
!            ;; WINDOW is live).
!            (window-min-height 1))
!       ;; Don't try to redisplay with the cursor at the end on its own
!       ;; line--that would force a scroll and spoil things.
!       (when (and (eobp) (bolp) (not (bobp)))
!         (set-window-point window (1- (window-point))))
!       ;; Use condition-case to handle any fixed-size windows and other
!       ;; pitfalls nearby.
!       (condition-case nil
!           ;; Adjust WINDOW's height to the nominally correct one
!           ;; (which may actually be slightly off because of variable
!           ;; height text, etc).
!           (unless (zerop delta)
!             (enlarge-window delta)
!             ;; Check if the last line is surely fully visible.  If
!             ;; not, enlarge the window.
!             (let ((end (save-excursion
!                          (goto-char (point-max))
!                          (when (and (bolp) (not (bobp)))
!                            ;; Don't include final newline
!                            (backward-char 1))
!                          (when truncate-lines
!                            ;; If line-wrapping is turned off, test the
!                            ;; beginning of the last line for
!                            ;; visibility instead of the end, as the
!                            ;; end of the line could be invisible by
!                            ;; virtue of extending past the edge of the
!                            ;; window.
!                            (forward-line 0))
!                          (point))))
!               (set-window-vscroll window 0)
!               (while (and (< (window-height) max-height)
!                           (not (pos-visible-in-window-p end)))
!                 (enlarge-window 1))))
!         (error nil))))))
  
  (defun window-safely-shrinkable-p (&optional window)
    "Return t if WINDOW can be shrunk without shrinking other windows.