(reveal-last-tick): New var.

(reveal-post-command): Use it to avoid closing overlays when we're
appending text to them.

1 files changed, 47 insertions, 32 deletions

diff --git a/lisp/reveal.el b/lisp/reveal.el
index 2809db23e2e..393400071a6 100644
--- a/lisp/reveal.el
+++ b/lisp/reveal.el
@@ -1,6 +1,6 @@
 ;;; reveal.el --- Automatically reveal hidden text at point
 
-;; Copyright (C) 2000, 2001  Free Software Foundation, Inc.
+;; Copyright (C) 2000, 2001, 2004  Free Software Foundation, Inc.
 
 ;; Author: Stefan Monnier <monnier@cs.yale.edu>
 ;; Keywords: outlines
@@ -59,6 +59,9 @@
 (defvar reveal-open-spots nil)
 (make-variable-buffer-local 'reveal-open-spots)
 
+(defvar reveal-last-tick nil)
+(make-variable-buffer-local 'reveal-last-tick)
+
 ;; Actual code
 
 (defun reveal-post-command ()
@@ -90,16 +93,16 @@
                           (overlays-at (point))))
          (push (cons (selected-window) ol) reveal-open-spots)
          (setq old-ols (delq ol old-ols))
-         (let ((open (overlay-get ol 'reveal-toggle-invisible)))
+         (let ((open (overlay-get ol 'reveal-toggle-invisible)) inv)
            (when (or open
-                     (let ((inv (overlay-get ol 'invisible)))
-                       (and inv (symbolp inv)
-                            (or (setq open (or (get inv 'reveal-toggle-invisible)
-                                               (overlay-get ol 'isearch-open-invisible-temporary)))
-                                (overlay-get ol 'isearch-open-invisible)
-                                (and (consp buffer-invisibility-spec)
-                                     (assq inv buffer-invisibility-spec)))
-                            (overlay-put ol 'reveal-invisible inv))))
+                     (and (setq inv (overlay-get ol 'invisible))
+                          (symbolp inv)
+                          (or (setq open (or (get inv 'reveal-toggle-invisible)
+                                             (overlay-get ol 'isearch-open-invisible-temporary)))
+                              (overlay-get ol 'isearch-open-invisible)
+                              (and (consp buffer-invisibility-spec)
+                                   (assq inv buffer-invisibility-spec)))
+                          (overlay-put ol 'reveal-invisible inv)))
              (if (null open)
                  (overlay-put ol 'invisible nil)
                ;; Use the provided opening function and repeat (since the
@@ -113,27 +116,39 @@
                         (setq repeat nil)
                         (overlay-put ol 'invisible nil))))))))
      ;; Close old overlays.
-     (dolist (ol old-ols)
-       (when (and (eq (current-buffer) (overlay-buffer ol))
-                  (not (rassq ol reveal-open-spots)))
-         (if (and (>= (point) (save-excursion
-                                (goto-char (overlay-start ol))
-                                (line-beginning-position 1)))
-                  (<= (point) (save-excursion
-                                (goto-char (overlay-end ol))
-                                (line-beginning-position 2))))
-             ;; Still near the overlay: keep it open.
-             (push (cons (selected-window) ol) reveal-open-spots)
-           ;; Really close it.
-           (let ((open (overlay-get ol 'reveal-toggle-invisible)) inv)
-             (if (or open
-                     (and (setq inv (overlay-get ol 'reveal-invisible))
-                          (setq open (or (get inv 'reveal-toggle-invisible)
-                                         (overlay-get ol 'isearch-open-invisible-temporary)))))
-                 (condition-case err
-                     (funcall open ol t)
-                   (error (message "!!Reveal-hide: %s !!" err)))
-               (overlay-put ol 'invisible inv)))))))
+     (if (not (eq reveal-last-tick
+                  (setq reveal-last-tick (buffer-modified-tick))))
+         ;; The buffer was modified since last command: let's refrain from
+         ;; closing any overlay because it tends to behave poorly when
+         ;; inserting text at the end of an overlay (basically the overlay
+         ;; should be rear-advance when it's open, but things like
+         ;; outline-minor-mode make it non-rear-advance because it's
+         ;; a better choice when it's closed).
+         (dolist (ol old-ols)
+           (push (cons (selected-window) ol) reveal-open-spots))
+       ;; The last command was only a point motion or some such
+       ;; non-buffer-modifying command.  Let's close whatever can be closed.
+       (dolist (ol old-ols)
+         (when (and (eq (current-buffer) (overlay-buffer ol))
+                    (not (rassq ol reveal-open-spots)))
+           (if (and (>= (point) (save-excursion
+                                  (goto-char (overlay-start ol))
+                                  (line-beginning-position 1)))
+                    (<= (point) (save-excursion
+                                  (goto-char (overlay-end ol))
+                                  (line-beginning-position 2))))
+               ;; Still near the overlay: keep it open.
+               (push (cons (selected-window) ol) reveal-open-spots)
+             ;; Really close it.
+             (let ((open (overlay-get ol 'reveal-toggle-invisible)) inv)
+               (if (or open
+                       (and (setq inv (overlay-get ol 'reveal-invisible))
+                            (setq open (or (get inv 'reveal-toggle-invisible)
+                                           (overlay-get ol 'isearch-open-invisible-temporary)))))
+                   (condition-case err
+                       (funcall open ol t)
+                     (error (message "!!Reveal-hide: %s !!" err)))
+                 (overlay-put ol 'invisible inv))))))))
    (error (message "Reveal: %s" err)))))
 
 ;;;###autoload
@@ -171,5 +186,5 @@ With zero or negative ARG turn mode off."
 
 (provide 'reveal)
 
-;;; arch-tag: 96ba0242-2274-4ed7-8e10-26bc0707b4d8
+;; arch-tag: 96ba0242-2274-4ed7-8e10-26bc0707b4d8
 ;;; reveal.el ends here