2002-02-14 Per Abrahamsen <abraham@dina.kvl.dk>

	* facemenu.el (describe-text-done): New function.
	(describe-text-mode-map): New variable.
	(describe-text-mode-hook): New option.
	(describe-text-mode): New function.
	(describe-text-widget): New function.
	(describe-text-sexp): New function.
	(describe-text-properties): New function.
	(describe-text-category): New command.
	(describe-text-at): New command.
	(facemenu-menu): Replace `list-text-properties-at' with
	`describe-text-at' in the menu.

	* wid-edit.el (widgetp): New function.
	* wid-edit.el (widget-keymap, widget-insert, widget-setup):
	Autoloaded.

	* emacs-lisp/pp.el (pp-to-string): Autoloaded.

	* wid-browse.el: Removed version and x-url keywords.

1 files changed, 178 insertions, 3 deletions

diff --git a/lisp/facemenu.el b/lisp/facemenu.el
index 7e44fa5012c..59e27e2dbd5 100644
--- a/lisp/facemenu.el
+++ b/lisp/facemenu.el
@@ -1,6 +1,6 @@
 ;;; facemenu.el --- create a face menu for interactively adding fonts to text
 
-;; Copyright (c) 1994, 1995, 1996, 2001 Free Software Foundation, Inc.
+;; Copyright (c) 1994, 1995, 1996, 2001, 2002 Free Software Foundation, Inc.
 
 ;; Author: Boris Goldowsky <boris@gnu.org>
 ;; Keywords: faces
@@ -94,6 +94,10 @@
 
 (provide 'facemenu)
 
+(eval-when-compile 
+  (require 'help)
+  (require 'button))
+
 ;;; Provide some binding for startup:
 ;;;###autoload (define-key global-map "\M-g" 'facemenu-keymap)
 ;;;###autoload (autoload 'facemenu-keymap "facemenu" "Keymap for face-changing commands." t 'keymap)
@@ -240,8 +244,8 @@ when they are created."
 (let ((map facemenu-menu))
   (define-key map [dc] (cons (purecopy "Display Colors") 'list-colors-display))
   (define-key map [df] (cons (purecopy "Display Faces") 'list-faces-display))
-  (define-key map [dp] (cons (purecopy "List Properties")
-			     'list-text-properties-at))
+  (define-key map [dp] (cons (purecopy "Describe Text")
+			     'describe-text-at))
   (define-key map [ra] (cons (purecopy "Remove Text Properties")
 			     'facemenu-remove-all))
   (define-key map [rm] (cons (purecopy "Remove Face Properties")
@@ -463,6 +467,177 @@ These special properties include `invisible', `intangible' and `read-only'."
     (remove-text-properties 
      start end '(invisible nil intangible nil read-only nil))))
 
+;;; Describe-Text Mode.
+
+(defun describe-text-done ()
+  "Delete the current window or bury the current buffer."
+  (interactive)
+  (if (> (count-windows) 1)
+      (delete-window)
+    (bury-buffer)))
+
+(defvar describe-text-mode-map 
+  (let ((map (make-sparse-keymap)))
+    (if (boundp 'widget-keymap)
+	(set-keymap-parent map widget-keymap)
+      ;; Copy from wid-edit.el if widget-keymap isn't in loaddefs.el
+      ;; Needed for bootstrap purposes, can hopefully be removed when 
+      ;; loaddefs.el is updated.
+      ;; -- Per Abrahamsen <abraham@dina.kvl.dk>, 2002-02-14.
+      (define-key map "\t" 'widget-forward)
+      (define-key map [(shift tab)] 'widget-backward)
+      (define-key map [backtab] 'widget-backward)
+      (define-key map [down-mouse-2] 'widget-button-click)
+      (define-key map "\C-m" 'widget-button-press))
+    (define-key map "q" 'describe-text-done)
+    map)
+  "Keymap for `describe-text-mode'.")
+  
+(defcustom describe-text-mode-hook nil
+  "List of hook functions ran by `describe-text-mode'."
+  :type 'hook)
+
+(defun describe-text-mode ()
+  "Major mode for buffers created by `describe-text-at'.
+
+\\{describe-text-mode-map}
+Entry to this mode calls the value of `describe-text-mode-hook'
+if that value is non-nil."
+  (kill-all-local-variables)
+  (setq major-mode 'describe-text-mode
+	mode-name "Describe-Text")
+  (use-local-map describe-text-mode-map)
+  (widget-setup)
+  (run-hooks 'describe-text-mode-hook))
+
+;;; Describe-Text Utilities.
+
+(defun describe-text-widget (widget)
+  "Insert text to describe WIDGET in the current buffer."
+  (widget-create 'link
+		 :notify `(lambda (&rest ignore)
+			    (widget-browse ',widget))
+		 (format "%S" (if (symbolp widget) 
+				  widget
+				(car widget))))
+  (widget-insert " ")
+  (widget-create 'info-link :tag "widget" "(widget)Top"))
+
+(defun describe-text-sexp (sexp)
+  "Insert a short description of SEXP in the current buffer."
+  (let ((pp (condition-case signal
+		(pp-to-string sexp)
+	      (error (prin1-to-string signal)))))
+    (when (string-match "\n\\'" pp)
+      (setq pp (substring pp 0 (1- (length pp)))))
+    (if (cond ((string-match "\n" pp)
+	       nil)
+	      ((> (length pp) (- (window-width) (current-column)))
+	       nil)
+	      (t t))
+	(widget-insert pp)
+      (widget-create 'push-button
+		     :tag "show"
+		     :action (lambda (widget &optional event)
+			       (with-output-to-temp-buffer
+				   "*Pp Eval Output*"
+				 (princ (widget-get widget :value))))
+		     pp))))
+  
+
+(defun describe-text-properties (properties)
+  "Insert a description of PROPERTIES in the current buffer.
+PROPERTIES should be a list of overlay or text properties.
+The `category' property is made into a widget button that call 
+`describe-text-category' when pushed."
+  (while properties
+    (widget-insert (format "  %-20s " (car properties)))
+    (let ((key (nth 0 properties))
+	  (value (nth 1 properties)))
+      (cond ((eq key 'category)
+	     (widget-create 'link 
+			    :notify `(lambda (&rest ignore)
+				       (describe-text-category ',value))
+			    (format "%S" value)))
+	    ((widgetp value)
+	     (describe-text-widget value))
+	    (t
+	     (describe-text-sexp value))))
+    (widget-insert "\n")
+    (setq properties (cdr (cdr properties)))))
+
+;;; Describe-Text Commands.
+
+(defun describe-text-category (category)
+  "Describe a text property category."
+  (interactive "S")
+  (when (get-buffer "*Text Category*")
+    (kill-buffer "*Text Category*"))
+  (save-excursion
+    (with-output-to-temp-buffer "*Text Category*"
+      (set-buffer "*Text Category*")
+      (widget-insert "Category " (format "%S" category) ":\n\n")
+      (describe-text-properties (symbol-plist category))
+      (describe-text-mode)
+      (goto-char (point-min)))))
+
+;;;###autoload
+(defun describe-text-at (pos)
+  "Describe widgets, buttons, overlays and text properties at POS."
+  (interactive "d")
+  (when (eq (current-buffer) (get-buffer "*Text Description*"))
+    (error "Can't do self inspection"))
+  (let* ((properties (text-properties-at pos))
+	 (overlays (overlays-at pos))
+	 overlay
+	 (wid-field (get-char-property pos 'field))
+	 (wid-button (get-char-property pos 'button))
+	 (wid-doc (get-char-property pos 'widget-doc))
+	 ;; If button.el is not loaded, we have no buttons in the text.
+	 (button (and (fboundp 'button-at) (button-at pos)))
+	 (button-type (and button (button-type button)))
+	 (button-label (and button (button-label button)))
+	 (widget (or wid-field wid-button wid-doc)))
+    (if (not (or properties overlays))
+	(message "This is plain text.")
+      (when (get-buffer "*Text Description*")
+	(kill-buffer "*Text Description*"))
+      (save-excursion
+	(with-output-to-temp-buffer "*Text Description*"
+	  (set-buffer "*Text Description*")
+	  (widget-insert "Text content at position " (format "%d" pos) ":\n\n")
+	  ;; Widgets
+	  (when (widgetp widget)
+	    (widget-insert (cond (wid-field "This is an editable text area")
+				 (wid-button "This is an active area")
+				 (wid-doc "This is documentation text")))
+	    (widget-insert " of a ")
+	    (describe-text-widget widget)
+	    (widget-insert ".\n\n"))
+	  ;; Buttons
+	  (when (and button (not (widgetp wid-button)))
+	    (widget-insert "Here is a " (format "%S" button-type) 
+			   " button labeled `" button-label "'.\n\n"))
+	  ;; Overlays
+	  (when overlays
+	    (if (eq (length overlays) 1)
+		(widget-insert "There is an overlay here:\n")
+	      (widget-insert "There are " (format "%d" (length overlays))
+			     " overlays here:\n"))
+	    (dolist (overlay overlays)
+	      (widget-insert " From " (format "%d" (overlay-start overlay)) 
+			     " to " (format "%d" (overlay-end overlay)) "\n")
+	      (describe-text-properties (overlay-properties overlay)))
+	    (widget-insert "\n"))
+	  ;; Text properties
+	  (when properties
+	    (widget-insert "There are text properties here:\n")
+	    (describe-text-properties properties))
+	  (describe-text-mode)
+	  (goto-char (point-min)))))))
+
+;;; List Text Properties
+
 ;;;###autoload
 (defun list-text-properties-at (p)
   "Pop up a buffer listing text-properties at LOCATION."