Support resizing frames and windows pixelwise.

* dispextern.h (enum window_part): Add ON_SCROLL_BAR,
ON_RIGHT_DIVIDER and ON_BOTTOM_DIVIDER.
(struct glyph_matrix): Replace window_left_col and
window_top_line by window_pixel_left and window_pixel_top.
(WINDOW_WANTS_MODELINE_P, WINDOW_WANTS_HEADER_LINE_P): Minor
rewrite.
(enum face_id): Add WINDOW_DIVIDER_FACE_ID.
(draw_window_divider, move_it_to, x_draw_right_divider)
(x_draw_bottom_divider, change_frame_size): Add or fix
declarations.
* dispnew.c (change_frame_size_1): Change prototype.
(adjust_glyph_matrix, required_matrix_width)
(adjust_frame_glyphs_for_window_redisplay): Use pixel
values instead of lines and columns.
(marginal_area_string): Use WINDOW_FRINGES_WIDTH instead of
WINDOW_TOTAL_FRINGE_WIDTH.
(handle_window_change_signal, do_pending_window_change)
(init_display): Adjusts calls of change_frame_size.
(change_frame_size, change_frame_size_1): Handle pixelwise
changes.
* frame.c (Qright_divider_width, Qbottom_divider_width): New
Lisp objects.
(set_menu_bar_lines_1, set_menu_bar_lines, make_frame)
(make_terminal_frame, Fmake_terminal_frame, Fframe_parameters)
(x_set_internal_border_width, x_set_vertical_scroll_bars)
(x_set_scroll_bar_width, x_figure_window_size): Handle pixel
values.
(set_frame_param): New function.
(Fframe_text_cols, Fframe_text_lines, Fframe_total_cols)
(Fframe_text_width, Fframe_text_height, Fscroll_bar_width)
(Ffringe_width, Fborder_width, Fright_divider_width)
(Fbottom_divider_width): New functions, defsubr them.
(Fset_frame_height, Fset_frame_width, Fset_frame_size): New
argument pixelwise.
(struct frame_parm_table): New members Qright_divider_width and
Qbottom_divider_width.
(x_set_frame_parameters): Handle parameters for pixelwise sizes.
(x_report_frame_params): Handle Qright_divider_width and
Qbottom_divider_width.
(x_set_right_divider_width, x_set_bottom_divider_width): New
functions.
(frame_resize_pixelwise): New option.
* frame.h (struct frame): Add tool_bar_height, menu_bar_height,
new_pixelwise, right_divider_width and bottom_divider_width;
remove total_lines; rename text_lines, text_cols, new_text_lines
and new_text_cols to text_height, text_width, new_height and
new_width respectively.
(FRAME_LINES, FRAME_COLS): Rename to FRAME_TEXT_HEIGHT and
FRAME_TEXT_WIDTH respectively.
(FRAME_MENU_BAR_HEIGHT, FRAME_TOOL_BAR_HEIGHT)
(FRAME_RIGHT_DIVIDER_WIDTH, FRAME_BOTTOM_DIVIDER_WIDTH)
(FRAME_TEXT_TO_PIXEL_WIDTH, FRAME_PIXEL_TO_TEXT_WIDTH): New
macros.
(FRAME_TOP_MARGIN_HEIGHT, FRAME_LEFT_SCROLL_BAR_AREA_WIDTH)
(FRAME_RIGHT_SCROLL_BAR_AREA_WIDTH, FRAME_SCROLL_BAR_AREA_WIDTH)
(SET_FRAME_COLS, SET_FRAME_WIDTH, SET_FRAME_HEIGHT)
(FRAME_TEXT_COLS_TO_PIXEL_WIDTH, FRAME_PIXEL_WIDTH_TO_TEXT_COLS)
(FRAME_TEXT_COLS_TO_PIXEL_WIDTH): Rewrite macros.
(FRAME_TOTAL_COLS_ARG): Remove macro.
* fringe.c (draw_fringe_bitmap_1): Handle right divder.
* gtkutil.c (xg_frame_resized, xg_frame_set_char_size)
(x_wm_set_size_hint): Handle frame pixel sizes.
* indent.c (compute_motion, Fcompute_motion): Call
window_body_width instead of window_body_cols.
* keyboard.c (Qright_divider, Qbottom_divider): New symbols.
(make_lispy_position): Handle right and bottom dividers.
(Fsuspend_emacs): Pixelize call of change_frame_size.
* keyboard.h: Extern Qright_divider, Qbottom_divider.
* lisp.h: Extern set_frame_param.
* nsfns.m (x_set_tool_bar_lines): Pixelize call of
x_set_window_size.
(Fx_create_frame): Add entry for vertical_drag_cursor.  Pixelize
call of change_frame_size.
* nsterm.h (struct ns_output): Add vertical_drag_cursor.
* nsterm.m (ns_update_window_end): Optionally draw right
divider.
(x_set_window_size): Add argument pixelwise.  Call
check_frame_size and change_frame_size with pixelwise zero.
(ns_draw_window_divider): New function.
(ns_redisplay_interface): Add ns_draw_window_divider.
(updateFrameSize:): Call change_frame_size with pixelwise zero.
(x_new_font): Call x_set_window_size with pixelwise zero.
* print.c (print_object): For a window print its sequence
number again.
* term.c (Fresume_tty): Pixelize call of change_frame_size.
* w32fns.c (x_set_mouse_color): Handle vertical drag cursor.
(x_set_menu_bar_lines, x_set_tool_bar_lines): Calculate pixelwise.
(w32_createwindow): Use scroll bar area width.
(w32_wnd_proc): Handle bottom divider width.  For
WM_WINDOWPOSCHANGING return zero if we resize pixelwise.
(Fx_create_frame): Default divider width parameters.  Caclulate
sizes pixelwise.  Add vertical drag cursor support.
(x_create_tip_frame): Default divider widths to zero.  Pixelize
call to change_frame_size.
(Fx_show_tip): Add handling of divider widths.  Pixelize window
position and sizes.
(Fw32_frame_rect): New function.
(frame_parm_handler w32_frame_parm_handlers): Add divider
widths.
(Vx_window_vertical_drag_shape): Add variable.
* w32inevt.c (resize_event, maybe_generate_resize_event):
Pixelize change_frame_size calls.
* w32menu.c (set_frame_menubar): Pixelize x_set_window_size
call.
* w32term.c (w32_draw_window_divider): New function.
(x_update_window_end): Handle right divider.
(w32_draw_fringe_bitmap, x_scroll_run)
(w32_set_vertical_scroll_bar): Pixelize scrollbar widths.
(w32_read_socket): Handle SIZE_MAXIMIZED separately.  Calculate
new frame sizes pixelwise.
(x_new_font): Pixelize call to x_set_window_size.
(x_check_fullscreen): Pixelize call to change_frame_size.
(x_set_window_size_1, x_set_window_size): New argument
pixelwise.  Calculate pixelwise.
(x_wm_set_size_hint): Use scroll bar area width.
(w32_redisplay_interface): Add w32_draw_window_divider.
* w32term.h (struct w32_output): Add vertical drag cursor.
* widget.c (set_frame_size, update_wm_hints)
(EmacsFrameResize, EmacsFrameSetValues): Pixelize calls of
change_frame_size.
(EmacsFrameSetCharSize): Pixelize call of x_set_window_size.
* window.c (sequence_number): Restore.
(Fwindow_pixel_width, Fwindow_pixel_height)
(Fwindow_mode_line_height, Fwindow_header_line_height)
(window_pixel_to_total, Frun_window_scroll_functions)
(Fset_window_new_pixel, window_resize_apply_total)
(Fwindow_resize_apply_total): New functions.
(window_body_height, window_body_width): Rename from
window_body_lines.  New argument PIXELWISE.  Calculate
pixelwise.
(Fwindow_body_height, Fwindow_body_width): New argument
PIXELWISE.
(coordinates_in_window, window_relative_x_coord): Use window's
pixel width instead of total width.
(replace_window, recombine_windows): Initialize pixel values.
(resize_root_window, resize_frame_windows, grow_mini_window)
(shrink_mini_window): New argument PIXELWISE.  Calculate
pixelwise.
(Fdelete_other_windows_internal, adjust_window_margins)
(window_resize_check, window_resize_apply)
(Fdelete_window_internal, Fresize_mini_window_internal)
(Fwindow_text_width, Fwindow_text_height): Calculate pixelwise.
(check_frame_size): Rename arguments.  New argument PIXELWISE.
Calculate pixelwise.
(set_window_buffer): Make samebuf bool.  Run configuration change
hook only if buffer changed.
(Fset_window_buffer): Rewrite doc-string.
(make_window): Initialize new_pixel slot.
(Fwindow_resize_apply): Check pixel size of root window.
(Fsplit_window_internal): Call 2nd argument pixel_size.
Calculate pixelwise.
(Fscroll_left, Fscroll_right): Call window_body_width instead of
window_body_cols.
(save_window_data): New slots frame_text_width,
frame_text_height, frame_menu_bar_height, frame_tool_bar_height.
(saved_window): New slots pixel_left, pixel_top, pixel_height,
pixel_width.
(Fcurrent_window_configuration, Fset_window_configuration)
(save_window_save, compare_window_configurations): Handle new
slots in save_window_data and saved_window.
(Fset_window_scroll_bars): Fix doc-string.
(window_resize_pixelwise): New variable.
(coordinates_in_window, Fcoordinates_in_window_p): Handle
dividers.
(make_parent_window): Adjust sequence_number.
(Fwindow_right_divider_width, Fwindow_bottom_divider_width): New
functions.
* window.h (struct window): New members new_pixel, pixel_left,
pixel_top, pixel_width, pixel_height.  Restore sequence_number.
(wset_new_pixel): New function.
(WINDOW_PIXEL_WIDTH, WINDOW_PIXEL_HEIGHT)
(MIN_SAFE_WINDOW_PIXEL_WIDTH, MIN_SAFE_WINDOW_PIXEL_HEIGHT)
(WINDOW_LEFT_PIXEL_EDGE, WINDOW_RIGHT_PIXEL_EDGE)
(WINDOW_TOP_PIXEL_EDGE, WINDOW_BOTTOM_PIXEL_EDGE)
(WINDOW_BOTTOMMOST_P, WINDOW_BOX_LEFT_PIXEL_EDGE)
(WINDOW_BOX_RIGHT_PIXEL_EDGE, WINDOW_MARGINS_COLS)
(WINDOW_MARGINS_WIDTH, WINDOW_RIGHT_DIVIDER_WIDTH)
(WINDOW_BOTTOM_DIVIDER_WIDTH): New macros.
(WINDOW_TOTAL_FRINGE_WIDTH): Rename to WINDOW_FRINGES_WIDTH.
(WINDOW_TOTAL_WIDTH, WINDOW_TOTAL_HEIGHT): Remove macros.
(WINDOW_RIGHT_EDGE_X, WINDOW_LEFT_EDGE_X, WINDOW_TOP_EDGE_Y)
(WINDOW_BOTTOM_EDGE_Y, WINDOW_FULL_WIDTH_P, WINDOW_LEFTMOST_P)
(WINDOW_RIGHTMOST_P, WINDOW_BOX_LEFT_EDGE_X)
(WINDOW_BOX_RIGHT_EDGE_X, WINDOW_FRINGE_COLS)
(WINDOW_BOX_HEIGHT_NO_MODE_LINE, WINDOW_BOX_TEXT_HEIGHT):
Rewrite.
(resize_frame_windows, grow_mini_window, shrink_mini_window)
(window_body_width, check_frame_size): Adapt external declarations.
* xdisp.c (last_max_ascent): New integer.
(window_text_bottom_y): Handle bottom divider.
(window_box_width, window_box_height): Calculate pixelwise.
(get_glyph_string_clip_rects): Handle right divider.
(remember_mouse_glyph): When windows are resized pixelwise
proceed with width and height set to 1.
(init_iterator): Use WINDOW_PIXEL_WIDTH instead of
WINDOW_TOTAL_WIDTH.
(move_it_to): Calculate and return maximum x position
encountered.
(Fwindow_text_pixel_size): New function.
(resize_mini_window, update_tool_bar): Calculate pixelwise.
(tool_bar_lines_needed): Rename to tool_bar_height.  Calculate
pixelwise.
(Ftool_bar_lines_needed): Rename to Ftool_bar_height.  Calculate
pixelwise.
(redisplay_tool_bar): Calculate pixelwise.
(redisplay_window): Calculate pixelwise.  Handle dividers.
(draw_glyphs, x_clear_end_of_line, note_mouse_highlight)
(x_draw_vertical_border): Handle dividers.
(define_frame_cursor1): Handle vertical drag cursor.
(x_draw_right_divider, x_draw_bottom_divider): New functions.
(expose_window): Calculate pixelwise.  Handle dividers.
(init_xdisp): Initialize pixel values.
* xfaces.c (Qwindow_divider): New face.
(realize_basic_faces): Realize it.
* xfns.c (x_set_mouse_color): Handle vertical_drag_cursor.
(x_set_menu_bar_lines, x_set_tool_bar_lines): Calculate pixelwise.
(x_set_scroll_bar_default_width): Default actual width to 16.
(Fx_create_frame): Set sizes pixelwise.
(x_create_tip_frame): Default divider widths to zero.  Pixelize
call of change_frame_size.
(Fx_show_tip): Handle divider widths.  Initial pixel position
and sizes.
(frame_parm_handler x_frame_parm_handlers): Add divider widths.
(Vx_window_vertical_drag_shape): New option.
* xmenu.c (free_frame_menubar): Pixelize call of
x_set_window_size.
* xterm.c (x_draw_window_divider): New function.
(x_update_window_end): Optionally draw right divider.
(x_draw_fringe_bitmap, x_scroll_run, x_scroll_bar_create)
(XTset_vertical_scroll_bar): Use scroll bar pixel width.
(handle_one_xevent, x_new_font): Calculate pixelwise.
(x_set_window_size_1, x_set_window_size): New argument
pixelwise.  Calculate pixelwise.
(x_wm_set_size_hint): Pixelize call of check_frame_size.
(struct x_redisplay_interface): Add x_draw_window_divider.
* xterm.h (struct x_output): Add vertical_drag_cursor.

* cus-start.el (frame-resize-pixelwise)
(window-resize-pixelwise): New entries.
* emacs-lisp/debug.el (debug): Use window-total-height instead
of window-total-size.
* frame.el (tool-bar-lines-needed): Defalias to tool-bar-height.
* help.el (describe-bindings-internal): Call help-buffer
(temp-buffer-max-width): New option.
(resize-temp-buffer-window, help-window-setup)
(with-help-window): Rewrite.
* mouse.el (mouse-drag-line): Rewrite.  Add key bindings for
dragging dividers.
* window.el (frame-char-size, window-min-pixel-height)
(window-safe-min-pixel-height, window-safe-min-pixel-width)
(window-min-pixel-width, window-safe-min-pixel-size)
(window-combination-p, window-safe-min-size)
(window-resizable-p, window--size-to-pixel)
(window--pixel-to-size, window--resize-apply-p): New functions.
(window-safe-min-height): Fix doc-string.
(window-size, window-min-size, window--min-size-1)
(window-sizable, window-sizable-p, window--min-delta-1)
(window-min-delta, window--max-delta-1, window-max-delta)
(window--resizable, window--resizable-p, window-resizable)
(window-full-height-p, window-full-width-p, window-at-side-p)
(window--in-direction-2, window-in-direction)
(window--resize-reset-1, window--resize-mini-window)
(window-resize, window-resize-no-error)
(window--resize-child-windows-normal)
(window--resize-child-windows, window--resize-siblings)
(window--resize-this-window, window--resize-root-window)
(window--resize-root-window-vertically)
(adjust-window-trailing-edge, enlarge-window, shrink-window)
(maximize-window, minimize-window, delete-window)
(quit-restore-window, window-split-min-size, split-window)
(balance-windows-2, balance-windows)
(balance-windows-area-adjust, balance-windows-area)
(window--state-get-1, window-state-get, window--state-put-1)
(window--state-put-2, window-state-put)
(display-buffer-record-window, window--display-buffer): Make
functions handle pixelwise sizing of windows.
(display-buffer--action-function-custom-type)
(display-buffer-fallback-action): Add
display-buffer-in-previous-window.
(display-buffer-use-some-window): Resize window to height it had
before.
(fit-window-to-buffer-horizontally): New option.
(fit-frame-to-buffer): Describe new values.
(fit-frame-to-buffer-bottom-margin): Replace with
fit-frame-to-buffer-margins.
(window--sanitize-margin): New function.
(fit-frame-to-buffer, fit-window-to-buffer): Rewrite completely
using window-text-pixel-size.

1 files changed, 81 insertions, 55 deletions

diff --git a/lisp/help.el b/lisp/help.el
index c21d5b8c1d1..905c875ecb3 100644
--- a/lisp/help.el
+++ b/lisp/help.el
@@ -493,9 +493,8 @@ The optional argument MENUS, if non-nil, says to mention menu bindings.
 The optional argument PREFIX, if non-nil, should be a key sequence;
 then we display only bindings that start with that prefix."
   (let ((buf (current-buffer)))
-    (with-help-window "*Help*"
-      (with-current-buffer standard-output
-	(describe-buffer-bindings buf prefix menus)))))
+    (with-help-window (help-buffer)
+      (describe-buffer-bindings buf prefix menus))))
 
 (defun where-is (definition &optional insert)
   "Print message listing key sequences that invoke the command DEFINITION.
@@ -983,6 +982,23 @@ function is called, the window to be resized is selected."
   :group 'help
   :version "24.3")
 
+(defcustom temp-buffer-max-width
+  (lambda (buffer)
+    (if (eq (selected-window) (frame-root-window))
+	(/ (x-display-pixel-width) (frame-char-width) 2)
+      (/ (- (frame-width) 2) 2)))
+  "Maximum width of a window displaying a temporary buffer.
+This is effective only when Temp Buffer Resize mode is enabled.
+The value is the maximum width (in columns) which
+`resize-temp-buffer-window' will give to a window displaying a
+temporary buffer.  It can also be a function to be called to
+choose the width for such a buffer.  It gets one argument, the
+buffer, and should return a positive integer.  At the time the
+function is called, the window to be resized is selected."
+  :type '(choice integer function)
+  :group 'help
+  :version "24.4")
+
 (define-minor-mode temp-buffer-resize-mode
   "Toggle auto-resizing temporary buffer windows (Temp Buffer Resize Mode).
 With a prefix argument ARG, enable Temp Buffer Resize mode if ARG
@@ -1010,33 +1026,40 @@ and some others."
 
 (defun resize-temp-buffer-window (&optional window)
   "Resize WINDOW to fit its contents.
-WINDOW can be any live window and defaults to the selected one.
-
-Do not make WINDOW higher than `temp-buffer-max-height' nor
-smaller than `window-min-height'.  Do nothing if WINDOW is not
-vertically combined, some of its contents are scrolled out of
-view, or WINDOW was not created by `display-buffer'."
+WINDOW must be a live window and defaults to the selected one.
+Do not resize if WINDOW was not created by `display-buffer'.
+
+If WINDOW is part of a vertical combination, restrain its new
+size by `temp-buffer-max-height' and do not resize if its minimum
+accessible position is scrolled out of view.  If WINDOW is part
+of a horizontal combination, restrain its new size by
+`temp-buffer-max-width'.  In both cases, the value of the option
+`fit-window-to-buffer-horizontally' can inhibit resizing.
+
+If WINDOW is the root window of its frame, resize the frame
+provided `fit-frame-to-buffer' is non-nil."
   (setq window (window-normalize-window window t))
   (let ((height (if (functionp temp-buffer-max-height)
 		    (with-selected-window window
 		      (funcall temp-buffer-max-height (window-buffer)))
 		  temp-buffer-max-height))
+	(width (if (functionp temp-buffer-max-width)
+		   (with-selected-window window
+		     (funcall temp-buffer-max-width (window-buffer)))
+		 temp-buffer-max-width))
 	(quit-cadr (cadr (window-parameter window 'quit-restore))))
-    (cond
-     ;; Resize WINDOW iff it was split off by `display-buffer'.
-     ((and (eq quit-cadr 'window)
-	   (pos-visible-in-window-p (point-min) window)
-	   (window-combined-p window))
-      (fit-window-to-buffer window height))
-     ;; Resize FRAME iff it was created by `display-buffer'.
-     ((and fit-frame-to-buffer
-	   (eq quit-cadr 'frame)
-	   (eq window (frame-root-window window)))
-      (let ((frame (window-frame window)))
-	(fit-frame-to-buffer
-	 frame (+ (frame-height frame)
-		  (- (window-total-size window))
-		  height)))))))
+    ;; Resize WINDOW iff it was made by `display-buffer'.
+    (when (or (and (eq quit-cadr 'window)
+		   (or (and (window-combined-p window)
+			    (not (eq fit-window-to-buffer-horizontally
+				     'only))
+			    (pos-visible-in-window-p (point-min) window))
+		       (and (window-combined-p window t)
+			    fit-window-to-buffer-horizontally)))
+	      (and (eq quit-cadr 'frame)
+		     fit-frame-to-buffer
+		     (eq window (frame-root-window window))))
+	(fit-window-to-buffer window height nil width))))
 
 ;;; Help windows.
 (defcustom help-window-select 'other
@@ -1089,28 +1112,29 @@ window."
     (message "%s"
      (substitute-command-keys (concat quit-part scroll-part)))))
 
-(defun help-window-setup (help-window)
-  "Set up help window for `with-help-window'.
-HELP-WINDOW is the window used for displaying the help buffer."
-  (let* ((help-buffer (when (window-live-p help-window)
-			(window-buffer help-window)))
-	 (help-setup (when (window-live-p help-window)
-		       (car (window-parameter help-window 'quit-restore)))))
+(defun help-window-setup (window &optional value)
+  "Set up help window WINDOW for `with-help-window'.
+WINDOW is the window used for displaying the help buffer.
+Return VALUE."
+  (let* ((help-buffer (when (window-live-p window)
+			(window-buffer window)))
+	 (help-setup (when (window-live-p window)
+		       (car (window-parameter window 'quit-restore)))))
     (when help-buffer
       ;; Handle `help-window-point-marker'.
       (when (eq (marker-buffer help-window-point-marker) help-buffer)
-	(set-window-point help-window help-window-point-marker)
+	(set-window-point window help-window-point-marker)
 	;; Reset `help-window-point-marker'.
 	(set-marker help-window-point-marker nil))
 
       (cond
-       ((or (eq help-window (selected-window))
+       ((or (eq window (selected-window))
 	    (and (or (eq help-window-select t)
 		     (eq help-setup 'frame)
 		     (and (eq help-window-select 'other)
-			  (eq (window-frame help-window) (selected-frame))
+			  (eq (window-frame window) (selected-frame))
 			  (> (length (window-list nil 'no-mini)) 2)))
-		 (select-window help-window)))
+		 (select-window window)))
 	;; The help window is or gets selected ...
 	(help-window-display-message
 	 (cond
@@ -1118,12 +1142,12 @@ HELP-WINDOW is the window used for displaying the help buffer."
 	   ;; ... and is new, ...
 	   "Type \"q\" to delete help window")
 	  ((eq help-setup 'frame)
-	   "Type \"q\" to delete help frame")
+	   "Type \"q\" to quit the help frame")
 	  ((eq help-setup 'other)
 	   ;; ... or displayed some other buffer before.
 	   "Type \"q\" to restore previous buffer"))
-	 help-window t))
-       ((and (eq (window-frame help-window) (selected-frame))
+	 window t))
+       ((and (eq (window-frame window) (selected-frame))
 	     (= (length (window-list nil 'no-mini)) 2))
 	;; There are two windows on the help window's frame and the
 	;; other one is the selected one.
@@ -1133,7 +1157,7 @@ HELP-WINDOW is the window used for displaying the help buffer."
 	   "Type \\[delete-other-windows] to delete the help window")
 	  ((eq help-setup 'other)
 	   "Type \"q\" in help window to restore its previous buffer"))
-	 help-window 'other))
+	 window 'other))
        (t
 	;; The help window is not selected ...
 	(help-window-display-message
@@ -1144,40 +1168,42 @@ HELP-WINDOW is the window used for displaying the help buffer."
 	  ((eq help-setup 'other)
 	   ;; ... or displayed some other buffer before.
 	   "Type \"q\" in help window to restore previous buffer"))
-	 help-window))))))
+	 window))))
+    ;; Return VALUE.
+    value))
 
-;; `with-help-window' is a wrapper for `with-output-to-temp-buffer'
+;; `with-help-window' is a wrapper for `with-temp-buffer-window'
 ;; providing the following additional twists:
 
-;; (1) Issue more accurate messages telling how to scroll and quit the
-;; help window.
+;; (1) It puts the buffer in `help-mode' (via `help-mode-setup') and
+;; adds cross references (via `help-mode-finish').
+
+;; (2) It issues a message telling how to scroll and quit the help
+;; window (via `help-window-setup').
 
-;; (2) An option (customizable via `help-window-select') to select the
+;; (3) An option (customizable via `help-window-select') to select the
 ;; help window automatically.
 
-;; (3) A marker (`help-window-point-marker') to move point in the help
+;; (4) A marker (`help-window-point-marker') to move point in the help
 ;; window to an arbitrary buffer position.
 
 ;; Note: It's usually always wrong to use `help-print-return-message' in
 ;; the body of `with-help-window'.
 (defmacro with-help-window (buffer-name &rest body)
   "Display buffer with name BUFFER-NAME in a help window evaluating BODY.
-Select help window if the actual value of the user option
+Select help window if the current value of the user option
 `help-window-select' says so.  Return last value in BODY."
   (declare (indent 1) (debug t))
   `(progn
      ;; Make `help-window-point-marker' point nowhere.  The only place
      ;; where this should be set to a buffer position is within BODY.
      (set-marker help-window-point-marker nil)
-     (let* (help-window
-            (temp-buffer-show-hook
-             (cons (lambda () (setq help-window (selected-window)))
-                   temp-buffer-show-hook)))
-       ;; Return value returned by `with-output-to-temp-buffer'.
-       (prog1
-	   (with-output-to-temp-buffer ,buffer-name
-	     (progn ,@body))
-	 (help-window-setup help-window)))))
+     (let ((temp-buffer-window-setup-hook
+	    (cons 'help-mode-setup temp-buffer-window-setup-hook))
+	   (temp-buffer-window-show-hook
+	    (cons 'help-mode-finish temp-buffer-window-show-hook)))
+       (with-temp-buffer-window
+	,buffer-name nil 'help-window-setup (progn ,@body)))))
 
 ;; Called from C, on encountering `help-char' when reading a char.
 ;; Don't print to *Help*; that would clobber Help history.