Re: last character on line different when behind invis text?

[Richard Stallman <rms@gnu.org>]

Please try this replacement function.  The code does what the doc strings
says.  Whether that makes for correct behavior I am not sure.



(defun forward-visible-line (arg)
  "Move forward by ARG lines, ignoring currently invisible newlines only.
If ARG is negative, move backward -ARG lines.
If ARG is zero, move to the beginning of the current line."
  (condition-case nil
      (if (> arg 0)
	  (progn
	    (while (> arg 0)
	      (or (zerop (forward-line 1))
		  (signal 'end-of-buffer nil))
	      ;; If the newline we just skipped is invisible,
	      ;; don't count it.
	      (let ((prop
		     (get-char-property (1- (point)) 'invisible)))
		(if (if (eq buffer-invisibility-spec t)
			prop
		      (or (memq prop buffer-invisibility-spec)
			  (assq prop buffer-invisibility-spec)))
		    (setq arg (1+ arg))))
	      (setq arg (1- arg)))
	    ;; If invisible text follows, and it is a number of complete lines,
	    ;; skip it.
	    (let ((opoint (point)))
	      (while (and (not (eobp))
			  (let ((prop
				 (get-char-property (point) 'invisible)))
			    (if (eq buffer-invisibility-spec t)
				prop
			      (or (memq prop buffer-invisibility-spec)
				  (assq prop buffer-invisibility-spec)))))
		(goto-char
		 (if (get-text-property (point) 'invisible)
		     (or (next-single-property-change (point) 'invisible)
			 (point-max))
		   (next-overlay-change (point)))))
	      (unless (bolp)
		(goto-char opoint))))
	(let ((first t))
	  (while (or first (< arg 0))
	    (if (zerop arg)
		(beginning-of-line)
	      (or (zerop (forward-line -1))
		  (signal 'beginning-of-buffer nil)))
	    ;; If the newline we just moved to is invisible,
	    ;; don't count it.
	    (unless (bobp)
	      (let ((prop
		     (get-char-property (1- (point)) 'invisible)))
		(if (if (eq buffer-invisibility-spec t)
			prop
		      (or (memq prop buffer-invisibility-spec)
			  (assq prop buffer-invisibility-spec)))
		    (setq arg (1+ arg)))))
	    (setq first nil)
	    (setq arg (1+ arg)))
	  ;; If invisible text follows, and it is a number of complete lines,
	  ;; skip it.
	  (let ((opoint (point)))
	    (while (and (not (bobp))
			(let ((prop
			       (get-char-property (1- (point)) 'invisible)))
			  (if (eq buffer-invisibility-spec t)
			      prop
			    (or (memq prop buffer-invisibility-spec)
				(assq prop buffer-invisibility-spec)))))
	      (goto-char
	       (if (get-text-property (1- (point)) 'invisible)
		   (or (previous-single-property-change (point) 'invisible)
		       (point-min))
		 (previous-overlay-change (point)))))
	    (unless (bolp)
	      (goto-char opoint)))))
    ((beginning-of-buffer end-of-buffer)
     nil)))