[PATCH v2 13/38] Fix subtle differences between overlays and invisible text properties

[Ihor Radchenko <yantar92@gmail.com>]

* lisp/org-clock.el (org-clock-in):
(org-clock-find-position):
(org-clock-out):
* lisp/org.el (org-add-planning-info):
(org-scan-tags):
(org-global-tags-completion-table):
(org-make-tags-matcher):
(org-tags-expand):
(org--property-local-values):
(org-read-date-analyze):
(org-revert-all-org-buffers):
(org-beginning-of-line): Make sure that we inherit invisible state
when inserting text.
(org-sort-entries): Preserve invisible state after replace-match.

(org-log-beginning): Do not try to move by visible lines.

* lisp/org-macs.el (org-preserve-local-variables): Do not try to
preserve overlays.
* lisp/ox.el (org-export--generate-copy-script): Preserve folding
properties in export buffer.
* testing/lisp/test-ob.el (test-ob/preserve-results-indentation): Fix
test failure.
* testing/lisp/test-org.el (test-org/meta-return):
(test-org/custom-properties): Use new folding.
---
 lisp/org-clock.el        | 116 ++++----
 lisp/org-macs.el         |  12 +-
 lisp/org.el              | 560 ++++++++++++++++++++-------------------
 lisp/ox.el               |   4 +-
 testing/lisp/test-ob.el  |  12 +-
 testing/lisp/test-org.el |   3 +
 6 files changed, 367 insertions(+), 340 deletions(-)

diff --git a/lisp/org-clock.el b/lisp/org-clock.el
index 583b30237..ec87aaf8a 100644
--- a/lisp/org-clock.el
+++ b/lisp/org-clock.el
@@ -1373,14 +1373,14 @@ (defun org-clock-in (&optional select start-time)
 	   (sit-for 2)
 	   (throw 'abort nil))
 	  (t
-	   (insert-before-markers "\n")
+	   (insert-before-markers-and-inherit "\n")
 	   (backward-char 1)
 	   (when (and (save-excursion
 			(end-of-line 0)
 			(org-in-item-p)))
 	     (beginning-of-line 1)
 	     (indent-line-to (max 0 (- (current-indentation) 2))))
-	   (insert org-clock-string " ")
+	   (insert-and-inherit org-clock-string " ")
 	   (setq org-clock-effort (org-entry-get (point) org-effort-property))
 	   (setq org-clock-total-time (org-clock-sum-current-item
 				       (org-clock-get-sum-start)))
@@ -1581,19 +1581,23 @@ (defun org-clock-find-position (find-unclosed)
 		      count (1+ count))))))
 	(cond
 	 ((null positions)
-	  ;; Skip planning line and property drawer, if any.
-	  (org-end-of-meta-data)
-	  (unless (bolp) (insert "\n"))
-	  ;; Create a new drawer if necessary.
-	  (when (and org-clock-into-drawer
-		     (or (not (wholenump org-clock-into-drawer))
-			 (< org-clock-into-drawer 2)))
-	    (let ((beg (point)))
-	      (insert ":" drawer ":\n:END:\n")
-	      (org-indent-region beg (point))
-	      (org-flag-region
-	       (line-end-position -1) (1- (point)) t 'outline)
-	      (forward-line -1))))
+          (org-fold-core-ignore-modifications
+	      ;; Skip planning line and property drawer, if any.
+	      (org-end-of-meta-data)
+	    (unless (bolp) (insert-and-inherit "\n"))
+	    ;; Create a new drawer if necessary.
+	    (when (and org-clock-into-drawer
+		       (or (not (wholenump org-clock-into-drawer))
+			   (< org-clock-into-drawer 2)))
+	      (let ((beg (point)))
+	        (insert-and-inherit ":" drawer ":\n:END:\n")
+	        (org-indent-region beg (point))
+                (if (eq org-fold-core-style 'text-properties)
+	            (org-fold-region
+	             (line-end-position -1) (1- (point)) t 'drawer)
+                  (org-fold-region
+	           (line-end-position -1) (1- (point)) t 'outline))
+	        (forward-line -1)))))
 	 ;; When a clock drawer needs to be created because of the
 	 ;; number of clock items or simply if it is missing, collect
 	 ;; all clocks in the section and wrap them within the drawer.
@@ -1602,28 +1606,29 @@ (defun org-clock-find-position (find-unclosed)
 	    drawer)
 	  ;; Skip planning line and property drawer, if any.
 	  (org-end-of-meta-data)
-	  (let ((beg (point)))
-	    (insert
-	     (mapconcat
-	      (lambda (p)
-		(save-excursion
-		  (goto-char p)
-		  (org-trim (delete-and-extract-region
-			     (save-excursion (skip-chars-backward " \r\t\n")
-					     (line-beginning-position 2))
-			     (line-beginning-position 2)))))
-	      positions "\n")
-	     "\n:END:\n")
-	    (let ((end (point-marker)))
-	      (goto-char beg)
-	      (save-excursion (insert ":" drawer ":\n"))
-	      (org-flag-region (line-end-position) (1- end) t 'outline)
-	      (org-indent-region (point) end)
-	      (forward-line)
-	      (unless org-log-states-order-reversed
-		(goto-char end)
-		(beginning-of-line -1))
-	      (set-marker end nil))))
+          (org-fold-core-ignore-modifications
+	      (let ((beg (point)))
+	        (insert-and-inherit
+	         (mapconcat
+	          (lambda (p)
+		    (save-excursion
+		      (goto-char p)
+		      (org-trim (delete-and-extract-region
+			         (save-excursion (skip-chars-backward " \r\t\n")
+					         (line-beginning-position 2))
+			         (line-beginning-position 2)))))
+	          positions "\n")
+	         "\n:END:\n")
+	        (let ((end (point-marker)))
+	          (goto-char beg)
+	          (save-excursion (insert-and-inherit ":" drawer ":\n"))
+	          (org-fold-region (line-end-position) (1- end) t 'outline)
+	          (org-indent-region (point) end)
+	          (forward-line)
+	          (unless org-log-states-order-reversed
+		    (goto-char end)
+		    (beginning-of-line -1))
+	          (set-marker end nil)))))
 	 (org-log-states-order-reversed (goto-char (car (last positions))))
 	 (t (goto-char (car positions))))))))
 
@@ -1672,24 +1677,25 @@ (defun org-clock-out (&optional switch-to-state fail-quietly at-time)
 	    (if fail-quietly (throw 'exit nil) (error "Clock start time is gone")))
 	  (goto-char (match-end 0))
 	  (delete-region (point) (point-at-eol))
-	  (insert "--")
-	  (setq te (org-insert-time-stamp (or at-time now) 'with-hm 'inactive))
-	  (setq s (org-time-convert-to-integer
-		   (time-subtract
-		    (org-time-string-to-time te)
-		    (org-time-string-to-time ts)))
-		h (floor s 3600)
-		m (floor (mod s 3600) 60))
-	  (insert " => " (format "%2d:%02d" h m))
-	  (move-marker org-clock-marker nil)
-	  (move-marker org-clock-hd-marker nil)
-	  ;; Possibly remove zero time clocks.
-          (when (and org-clock-out-remove-zero-time-clocks
-		     (= 0 h m))
-            (setq remove t)
-	    (delete-region (line-beginning-position)
-			   (line-beginning-position 2)))
-          (org-clock-remove-empty-clock-drawer)
+          (org-fold-core-ignore-modifications
+              (insert-and-inherit "--")
+            (setq te (org-insert-time-stamp (or at-time now) 'with-hm 'inactive))
+            (setq s (org-time-convert-to-integer
+	             (time-subtract
+	              (org-time-string-to-time te)
+	              (org-time-string-to-time ts)))
+	          h (floor s 3600)
+	          m (floor (mod s 3600) 60))
+            (insert-and-inherit " => " (format "%2d:%02d" h m))
+            (move-marker org-clock-marker nil)
+            (move-marker org-clock-hd-marker nil)
+            ;; Possibly remove zero time clocks.
+            (when (and org-clock-out-remove-zero-time-clocks
+	               (= 0 h m))
+              (setq remove t)
+              (delete-region (line-beginning-position)
+		             (line-beginning-position 2)))
+            (org-clock-remove-empty-clock-drawer))
 	  (when org-clock-mode-line-timer
 	    (cancel-timer org-clock-mode-line-timer)
 	    (setq org-clock-mode-line-timer nil))
diff --git a/lisp/org-macs.el b/lisp/org-macs.el
index a894d4323..42a91781b 100644
--- a/lisp/org-macs.el
+++ b/lisp/org-macs.el
@@ -170,16 +170,8 @@ (defmacro org-preserve-local-variables (&rest body)
        (when local-variables
 	 (org-with-wide-buffer
 	  (goto-char (point-max))
-	  ;; If last section is folded, make sure to also hide file
-	  ;; local variables after inserting them back.
-	  (let ((overlay
-		 (cl-find-if (lambda (o)
-			       (eq 'outline (overlay-get o 'invisible)))
-			     (overlays-at (1- (point))))))
-	    (unless (bolp) (insert "\n"))
-	    (insert local-variables)
-	    (when overlay
-	      (move-overlay overlay (overlay-start overlay) (point-max)))))))))
+	  (unless (bolp) (insert "\n"))
+	  (insert local-variables))))))
 
 (defmacro org-no-popups (&rest body)
   "Suppress popup windows and evaluate BODY."
diff --git a/lisp/org.el b/lisp/org.el
index 9ebdb23e1..ca0a99681 100644
--- a/lisp/org.el
+++ b/lisp/org.el
@@ -6411,7 +6411,7 @@ (defun org-promote ()
        (replace-match "# " nil t))
       ((= level 1)
        (user-error "Cannot promote to level 0.  UNDO to recover if necessary"))
-      (t (replace-match up-head nil t)))
+      (t (replace-match (apply #'propertize up-head (text-properties-at (match-beginning 0))) t)))
      (unless (= level 1)
        (when org-auto-align-tags (org-align-tags))
        (when org-adapt-indentation (org-fixup-indentation (- diff))))
@@ -6426,9 +6426,10 @@ (defun org-demote ()
 	  (level (save-match-data (funcall outline-level)))
 	  (down-head (concat (make-string (org-get-valid-level level 1) ?*) " "))
 	  (diff (abs (- level (length down-head) -1))))
-     (replace-match down-head nil t)
-     (when org-auto-align-tags (org-align-tags))
-     (when org-adapt-indentation (org-fixup-indentation diff))
+     (org-fold-core-ignore-fragility-checks
+         (replace-match (apply #'propertize down-head (text-properties-at (match-beginning 0))) t)
+       (when org-auto-align-tags (org-align-tags))
+       (when org-adapt-indentation (org-fixup-indentation diff)))
      (run-hooks 'org-after-demote-entry-hook))))
 
 (defun org-cycle-level ()
@@ -8956,7 +8957,15 @@ (defun org-todo (&optional arg)
 			     this org-state block-reason)
 		    (throw 'exit nil)))))
 	    (store-match-data match-data)
-	    (replace-match next t t)
+            (org-fold-core-ignore-modifications
+                (save-excursion
+                  (goto-char (match-beginning 0))
+                  (setf (buffer-substring (match-beginning 0) (match-end 0)) "")
+                  (insert-and-inherit next)
+                  (unless (org-invisible-p (line-beginning-position))
+                    (org-fold-region (line-beginning-position)
+                                  (line-end-position)
+                                  nil))))
 	    (cond ((and org-state (equal this org-state))
 		   (message "TODO state was already %s" (org-trim next)))
 		  ((not (pos-visible-in-window-p hl-pos))
@@ -9697,81 +9706,82 @@ (defun org--deadline-or-schedule (arg type time)
   "Insert DEADLINE or SCHEDULE information in current entry.
 TYPE is either `deadline' or `scheduled'.  See `org-deadline' or
 `org-schedule' for information about ARG and TIME arguments."
-  (let* ((deadline? (eq type 'deadline))
-	 (keyword (if deadline? org-deadline-string org-scheduled-string))
-	 (log (if deadline? org-log-redeadline org-log-reschedule))
-	 (old-date (org-entry-get nil (if deadline? "DEADLINE" "SCHEDULED")))
-	 (old-date-time (and old-date (org-time-string-to-time old-date)))
-	 ;; Save repeater cookie from either TIME or current scheduled
-	 ;; time stamp.  We are going to insert it back at the end of
-	 ;; the process.
-	 (repeater (or (and (org-string-nw-p time)
-			    ;; We use `org-repeat-re' because we need
-			    ;; to tell the difference between a real
-			    ;; repeater and a time delta, e.g. "+2d".
-			    (string-match org-repeat-re time)
-			    (match-string 1 time))
-		       (and (org-string-nw-p old-date)
-			    (string-match "\\([.+-]+[0-9]+[hdwmy]\
+  (org-fold-core-ignore-modifications
+      (let* ((deadline? (eq type 'deadline))
+	     (keyword (if deadline? org-deadline-string org-scheduled-string))
+	     (log (if deadline? org-log-redeadline org-log-reschedule))
+	     (old-date (org-entry-get nil (if deadline? "DEADLINE" "SCHEDULED")))
+	     (old-date-time (and old-date (org-time-string-to-time old-date)))
+	     ;; Save repeater cookie from either TIME or current scheduled
+	     ;; time stamp.  We are going to insert it back at the end of
+	     ;; the process.
+	     (repeater (or (and (org-string-nw-p time)
+			        ;; We use `org-repeat-re' because we need
+			        ;; to tell the difference between a real
+			        ;; repeater and a time delta, e.g. "+2d".
+			        (string-match org-repeat-re time)
+			        (match-string 1 time))
+		           (and (org-string-nw-p old-date)
+			        (string-match "\\([.+-]+[0-9]+[hdwmy]\
 \\(?:[/ ][-+]?[0-9]+[hdwmy]\\)?\\)"
-					  old-date)
-			    (match-string 1 old-date)))))
-    (pcase arg
-      (`(4)
-       (if (not old-date)
-	   (message (if deadline? "Entry had no deadline to remove"
-		      "Entry was not scheduled"))
-	 (when (and old-date log)
-	   (org-add-log-setup (if deadline? 'deldeadline 'delschedule)
-			      nil old-date log))
-	 (org-remove-timestamp-with-keyword keyword)
-	 (message (if deadline? "Entry no longer has a deadline."
-		    "Entry is no longer scheduled."))))
-      (`(16)
-       (save-excursion
-	 (org-back-to-heading t)
-	 (let ((regexp (if deadline? org-deadline-time-regexp
-			 org-scheduled-time-regexp)))
-	   (if (not (re-search-forward regexp (line-end-position 2) t))
-	       (user-error (if deadline? "No deadline information to update"
-			     "No scheduled information to update"))
-	     (let* ((rpl0 (match-string 1))
-		    (rpl (replace-regexp-in-string " -[0-9]+[hdwmy]" "" rpl0))
-		    (msg (if deadline? "Warn starting from" "Delay until")))
-	       (replace-match
-		(concat keyword
-			" <" rpl
-			(format " -%dd"
-				(abs (- (time-to-days
-					 (save-match-data
-					   (org-read-date
-					    nil t nil msg old-date-time)))
-					(time-to-days old-date-time))))
-			">") t t))))))
-      (_
-       (org-add-planning-info type time 'closed)
-       (when (and old-date
-		  log
-		  (not (equal old-date org-last-inserted-timestamp)))
-	 (org-add-log-setup (if deadline? 'redeadline 'reschedule)
-			    org-last-inserted-timestamp
-			    old-date
-			    log))
-       (when repeater
-	 (save-excursion
-	   (org-back-to-heading t)
-	   (when (re-search-forward
-		  (concat keyword " " org-last-inserted-timestamp)
-		  (line-end-position 2)
-		  t)
-	     (goto-char (1- (match-end 0)))
-	     (insert " " repeater)
-	     (setq org-last-inserted-timestamp
-		   (concat (substring org-last-inserted-timestamp 0 -1)
-			   " " repeater
-			   (substring org-last-inserted-timestamp -1))))))
-       (message (if deadline? "Deadline on %s" "Scheduled to %s")
-		org-last-inserted-timestamp)))))
+					      old-date)
+			        (match-string 1 old-date)))))
+        (pcase arg
+          (`(4)
+           (if (not old-date)
+	       (message (if deadline? "Entry had no deadline to remove"
+		          "Entry was not scheduled"))
+	     (when (and old-date log)
+	       (org-add-log-setup (if deadline? 'deldeadline 'delschedule)
+			       nil old-date log))
+	     (org-remove-timestamp-with-keyword keyword)
+	     (message (if deadline? "Entry no longer has a deadline."
+		        "Entry is no longer scheduled."))))
+          (`(16)
+           (save-excursion
+	     (org-back-to-heading t)
+	     (let ((regexp (if deadline? org-deadline-time-regexp
+			     org-scheduled-time-regexp)))
+	       (if (not (re-search-forward regexp (line-end-position 2) t))
+	           (user-error (if deadline? "No deadline information to update"
+			         "No scheduled information to update"))
+	         (let* ((rpl0 (match-string 1))
+		        (rpl (replace-regexp-in-string " -[0-9]+[hdwmy]" "" rpl0))
+		        (msg (if deadline? "Warn starting from" "Delay until")))
+	           (replace-match
+		    (concat keyword
+			    " <" rpl
+			    (format " -%dd"
+				    (abs (- (time-to-days
+					     (save-match-data
+					       (org-read-date
+					        nil t nil msg old-date-time)))
+					    (time-to-days old-date-time))))
+			    ">") t t))))))
+          (_
+           (org-add-planning-info type time 'closed)
+           (when (and old-date
+		      log
+		      (not (equal old-date org-last-inserted-timestamp)))
+	     (org-add-log-setup (if deadline? 'redeadline 'reschedule)
+			     org-last-inserted-timestamp
+			     old-date
+			     log))
+           (when repeater
+	     (save-excursion
+	       (org-back-to-heading t)
+	       (when (re-search-forward
+		      (concat keyword " " org-last-inserted-timestamp)
+		      (line-end-position 2)
+		      t)
+	         (goto-char (1- (match-end 0)))
+	         (insert-and-inherit " " repeater)
+	         (setq org-last-inserted-timestamp
+		       (concat (substring org-last-inserted-timestamp 0 -1)
+			       " " repeater
+			       (substring org-last-inserted-timestamp -1))))))
+           (message (if deadline? "Deadline on %s" "Scheduled to %s")
+		    org-last-inserted-timestamp))))))
 
 (defun org-deadline (arg &optional time)
   "Insert a \"DEADLINE:\" string with a timestamp to make a deadline.
@@ -9876,101 +9886,102 @@ (defun org-add-planning-info (what &optional time &rest remove)
 the time to use.  If none is given, the user is prompted for
 a date.  REMOVE indicates what kind of entries to remove.  An old
 WHAT entry will also be removed."
-  (let (org-time-was-given org-end-time-was-given default-time default-input)
-    (when (and (memq what '(scheduled deadline))
-	       (or (not time)
-		   (and (stringp time)
-			(string-match "^[-+]+[0-9]" time))))
-      ;; Try to get a default date/time from existing timestamp
-      (save-excursion
-	(org-back-to-heading t)
-	(let ((end (save-excursion (outline-next-heading) (point))) ts)
-	  (when (re-search-forward (if (eq what 'scheduled)
-				       org-scheduled-time-regexp
-				     org-deadline-time-regexp)
-				   end t)
-	    (setq ts (match-string 1)
-		  default-time (org-time-string-to-time ts)
-		  default-input (and ts (org-get-compact-tod ts)))))))
-    (when what
-      (setq time
-	    (if (stringp time)
-		;; This is a string (relative or absolute), set
-		;; proper date.
-		(apply #'encode-time
-		       (org-read-date-analyze
-			time default-time (decode-time default-time)))
-	      ;; If necessary, get the time from the user
-	      (or time (org-read-date nil 'to-time nil
-				      (cl-case what
-					(deadline "DEADLINE")
-					(scheduled "SCHEDULED")
-					(otherwise nil))
-				      default-time default-input)))))
-    (org-with-wide-buffer
-     (org-back-to-heading t)
-     (let ((planning? (save-excursion
-			(forward-line)
-			(looking-at-p org-planning-line-re))))
-       (cond
-	(planning?
-	 (forward-line)
-	 ;; Move to current indentation.
-	 (skip-chars-forward " \t")
-	 ;; Check if we have to remove something.
-	 (dolist (type (if what (cons what remove) remove))
-	   (save-excursion
-	     (when (re-search-forward
-		    (cl-case type
-		      (closed org-closed-time-regexp)
-		      (deadline org-deadline-time-regexp)
-		      (scheduled org-scheduled-time-regexp)
-		      (otherwise (error "Invalid planning type: %s" type)))
-		    (line-end-position)
-		    t)
-	       ;; Delete until next keyword or end of line.
-	       (delete-region
-		(match-beginning 0)
-		(if (re-search-forward org-keyword-time-not-clock-regexp
-				       (line-end-position)
-				       t)
+  (org-fold-core-ignore-modifications
+      (let (org-time-was-given org-end-time-was-given default-time default-input)
+        (when (and (memq what '(scheduled deadline))
+	           (or (not time)
+		       (and (stringp time)
+			    (string-match "^[-+]+[0-9]" time))))
+          ;; Try to get a default date/time from existing timestamp
+          (save-excursion
+	    (org-back-to-heading t)
+	    (let ((end (save-excursion (outline-next-heading) (point))) ts)
+	      (when (re-search-forward (if (eq what 'scheduled)
+				           org-scheduled-time-regexp
+				         org-deadline-time-regexp)
+				       end t)
+	        (setq ts (match-string 1)
+		      default-time (org-time-string-to-time ts)
+		      default-input (and ts (org-get-compact-tod ts)))))))
+        (when what
+          (setq time
+	        (if (stringp time)
+		    ;; This is a string (relative or absolute), set
+		    ;; proper date.
+		    (apply #'encode-time
+		           (org-read-date-analyze
+			    time default-time (decode-time default-time)))
+	          ;; If necessary, get the time from the user
+	          (or time (org-read-date nil 'to-time nil
+				       (cl-case what
+				         (deadline "DEADLINE")
+				         (scheduled "SCHEDULED")
+				         (otherwise nil))
+				       default-time default-input)))))
+        (org-with-wide-buffer
+         (org-back-to-heading t)
+         (let ((planning? (save-excursion
+			    (forward-line)
+			    (looking-at-p org-planning-line-re))))
+           (cond
+	    (planning?
+	     (forward-line)
+	     ;; Move to current indentation.
+	     (skip-chars-forward " \t")
+	     ;; Check if we have to remove something.
+	     (dolist (type (if what (cons what remove) remove))
+	       (save-excursion
+	         (when (re-search-forward
+		        (cl-case type
+		          (closed org-closed-time-regexp)
+		          (deadline org-deadline-time-regexp)
+		          (scheduled org-scheduled-time-regexp)
+		          (otherwise (error "Invalid planning type: %s" type)))
+		        (line-end-position)
+		        t)
+	           ;; Delete until next keyword or end of line.
+	           (delete-region
 		    (match-beginning 0)
-		  (line-end-position))))))
-	 ;; If there is nothing more to add and no more keyword is
-	 ;; left, remove the line completely.
-	 (if (and (looking-at-p "[ \t]*$") (not what))
-	     (delete-region (line-end-position 0)
-			    (line-end-position))
-	   ;; If we removed last keyword, do not leave trailing white
-	   ;; space at the end of line.
-	   (let ((p (point)))
-	     (save-excursion
-	       (end-of-line)
-	       (unless (= (skip-chars-backward " \t" p) 0)
-		 (delete-region (point) (line-end-position)))))))
-	(what
-	 (end-of-line)
-	 (insert "\n")
-	 (when org-adapt-indentation
-	   (indent-to-column (1+ (org-outline-level)))))
-	(t nil)))
-     (when what
-       ;; Insert planning keyword.
-       (insert (cl-case what
-		 (closed org-closed-string)
-		 (deadline org-deadline-string)
-		 (scheduled org-scheduled-string)
-		 (otherwise (error "Invalid planning type: %s" what)))
-	       " ")
-       ;; Insert associated timestamp.
-       (let ((ts (org-insert-time-stamp
-		  time
-		  (or org-time-was-given
-		      (and (eq what 'closed) org-log-done-with-time))
-		  (eq what 'closed)
-		  nil nil (list org-end-time-was-given))))
-	 (unless (eolp) (insert " "))
-	 ts)))))
+		    (if (re-search-forward org-keyword-time-not-clock-regexp
+				           (line-end-position)
+				           t)
+		        (match-beginning 0)
+		      (line-end-position))))))
+	     ;; If there is nothing more to add and no more keyword is
+	     ;; left, remove the line completely.
+	     (if (and (looking-at-p "[ \t]*$") (not what))
+	         (delete-region (line-end-position 0)
+			        (line-end-position))
+	       ;; If we removed last keyword, do not leave trailing white
+	       ;; space at the end of line.
+	       (let ((p (point)))
+	         (save-excursion
+	           (end-of-line)
+	           (unless (= (skip-chars-backward " \t" p) 0)
+		     (delete-region (point) (line-end-position)))))))
+	    (what
+	     (end-of-line)
+	     (insert-and-inherit "\n")
+	     (when org-adapt-indentation
+	       (indent-to-column (1+ (org-outline-level)))))
+	    (t nil)))
+         (when what
+           ;; Insert planning keyword.
+           (insert-and-inherit (cl-case what
+		                 (closed org-closed-string)
+		                 (deadline org-deadline-string)
+		                 (scheduled org-scheduled-string)
+		                 (otherwise (error "Invalid planning type: %s" what)))
+	                       " ")
+           ;; Insert associated timestamp.
+           (let ((ts (org-insert-time-stamp
+		      time
+		      (or org-time-was-given
+		          (and (eq what 'closed) org-log-done-with-time))
+		      (eq what 'closed)
+		      nil nil (list org-end-time-was-given))))
+	     (unless (eolp) (insert " "))
+	     ts))))))
 
 (defvar org-log-note-marker (make-marker)
   "Marker pointing at the entry where the note is to be inserted.")
@@ -10020,13 +10031,19 @@ (defun org-log-beginning (&optional create)
 		 (throw 'exit nil))))
 	   ;; No drawer found.  Create one, if permitted.
 	   (when create
-	     (unless (bolp) (insert "\n"))
-	     (let ((beg (point)))
-	       (insert ":" drawer ":\n:END:\n")
-	       (org-indent-region beg (point))
-	       (org-flag-region (line-end-position -1)
-                                (1- (point)) t 'outline))
-	     (end-of-line -1)))))
+             ;; Avoid situation when we insert drawer right before
+             ;; first "*".  Otherwise, if the previous heading is
+             ;; folded, we are inserting after visible newline at
+             ;; the end of the fold, thus breaking the fold
+             ;; continuity.
+             (when (org-at-heading-p) (backward-char))
+             (org-fold-core-ignore-modifications
+	         (unless (bolp) (insert-and-inherit "\n"))
+	       (let ((beg (point)))
+	         (insert-and-inherit ":" drawer ":\n:END:\n")
+	         (org-indent-region beg (point))
+	         (org-fold-region (line-end-position -1) (1- (point)) t (if (eq org-fold-core-style 'text-properties) 'drawer 'outline)))))
+	   (end-of-line -1))))
       (t
        (org-end-of-meta-data org-log-state-notes-insert-after-drawers)
        (skip-chars-forward " \t\n")
@@ -10034,7 +10051,7 @@ (defun org-log-beginning (&optional create)
        (unless org-log-states-order-reversed
 	 (org-skip-over-state-notes)
 	 (skip-chars-backward " \t\n")
-	 (forward-line)))))
+	 (beginning-of-line 2)))))
    (if (bolp) (point) (line-beginning-position 2))))
 
 (defun org-add-log-setup (&optional purpose state prev-state how extra)
@@ -10160,34 +10177,35 @@ (defun org-store-log-note ()
       (push note lines))
     (when (and lines (not org-note-abort))
       (with-current-buffer (marker-buffer org-log-note-marker)
-	(org-with-wide-buffer
-	 ;; Find location for the new note.
-	 (goto-char org-log-note-marker)
-	 (set-marker org-log-note-marker nil)
-	 ;; Note associated to a clock is to be located right after
-	 ;; the clock.  Do not move point.
-	 (unless (eq org-log-note-purpose 'clock-out)
-	   (goto-char (org-log-beginning t)))
-	 ;; Make sure point is at the beginning of an empty line.
-	 (cond ((not (bolp)) (let ((inhibit-read-only t)) (insert "\n")))
-	       ((looking-at "[ \t]*\\S-") (save-excursion (insert "\n"))))
-	 ;; In an existing list, add a new item at the top level.
-	 ;; Otherwise, indent line like a regular one.
-	 (let ((itemp (org-in-item-p)))
-	   (if itemp
-	       (indent-line-to
-		(let ((struct (save-excursion
-				(goto-char itemp) (org-list-struct))))
-		  (org-list-get-ind (org-list-get-top-point struct) struct)))
-	     (org-indent-line)))
-	 (insert (org-list-bullet-string "-") (pop lines))
-	 (let ((ind (org-list-item-body-column (line-beginning-position))))
-	   (dolist (line lines)
-	     (insert "\n")
-	     (indent-line-to ind)
-	     (insert line)))
-	 (message "Note stored")
-	 (org-back-to-heading t)))))
+        (org-fold-core-ignore-modifications
+	    (org-with-wide-buffer
+	     ;; Find location for the new note.
+	     (goto-char org-log-note-marker)
+	     (set-marker org-log-note-marker nil)
+	     ;; Note associated to a clock is to be located right after
+	     ;; the clock.  Do not move point.
+	     (unless (eq org-log-note-purpose 'clock-out)
+	       (goto-char (org-log-beginning t)))
+	     ;; Make sure point is at the beginning of an empty line.
+	     (cond ((not (bolp)) (let ((inhibit-read-only t)) (insert-and-inherit "\n")))
+	           ((looking-at "[ \t]*\\S-") (save-excursion (insert-and-inherit "\n"))))
+	     ;; In an existing list, add a new item at the top level.
+	     ;; Otherwise, indent line like a regular one.
+	     (let ((itemp (org-in-item-p)))
+	       (if itemp
+	           (indent-line-to
+		    (let ((struct (save-excursion
+				    (goto-char itemp) (org-list-struct))))
+		      (org-list-get-ind (org-list-get-top-point struct) struct)))
+	         (org-indent-line)))
+	     (insert-and-inherit (org-list-bullet-string "-") (pop lines))
+	     (let ((ind (org-list-item-body-column (line-beginning-position))))
+	       (dolist (line lines)
+	         (insert-and-inherit "\n")
+	         (indent-line-to ind)
+	         (insert-and-inherit line)))
+	     (message "Note stored")
+	     (org-back-to-heading t))))))
   ;; Don't add undo information when called from `org-agenda-todo'.
   (set-window-configuration org-log-note-window-configuration)
   (with-current-buffer (marker-buffer org-log-note-return-to)
@@ -11318,34 +11336,35 @@ (defun org-set-tags (tags)
 
 This function assumes point is on a headline."
   (org-with-wide-buffer
-   (let ((tags (pcase tags
-		 ((pred listp) tags)
-		 ((pred stringp) (split-string (org-trim tags) ":" t))
-		 (_ (error "Invalid tag specification: %S" tags))))
-	 (old-tags (org-get-tags nil t))
-	 (tags-change? nil))
-     (when (functionp org-tags-sort-function)
-       (setq tags (sort tags org-tags-sort-function)))
-     (setq tags-change? (not (equal tags old-tags)))
-     (when tags-change?
-       ;; Delete previous tags and any trailing white space.
-       (goto-char (if (org-match-line org-tag-line-re) (match-beginning 1)
-		    (line-end-position)))
-       (skip-chars-backward " \t")
-       (delete-region (point) (line-end-position))
-       ;; Deleting white spaces may break an otherwise empty headline.
-       ;; Re-introduce one space in this case.
-       (unless (org-at-heading-p) (insert " "))
-       (when tags
-	 (save-excursion (insert " " (org-make-tag-string tags)))
-	 ;; When text is being inserted on an invisible region
-	 ;; boundary, it can be inadvertently sucked into
-	 ;; invisibility.
-	 (unless (org-invisible-p (line-beginning-position))
-	   (org-flag-region (point) (line-end-position) nil 'outline))))
-     ;; Align tags, if any.
-     (when tags (org-align-tags))
-     (when tags-change? (run-hooks 'org-after-tags-change-hook)))))
+   (org-fold-core-ignore-modifications
+       (let ((tags (pcase tags
+		     ((pred listp) tags)
+		     ((pred stringp) (split-string (org-trim tags) ":" t))
+		     (_ (error "Invalid tag specification: %S" tags))))
+	     (old-tags (org-get-tags nil t))
+	     (tags-change? nil))
+         (when (functionp org-tags-sort-function)
+           (setq tags (sort tags org-tags-sort-function)))
+         (setq tags-change? (not (equal tags old-tags)))
+         (when tags-change?
+           ;; Delete previous tags and any trailing white space.
+           (goto-char (if (org-match-line org-tag-line-re) (match-beginning 1)
+		        (line-end-position)))
+           (skip-chars-backward " \t")
+           (delete-region (point) (line-end-position))
+           ;; Deleting white spaces may break an otherwise empty headline.
+           ;; Re-introduce one space in this case.
+           (unless (org-at-heading-p) (insert " "))
+           (when tags
+	     (save-excursion (insert-and-inherit " " (org-make-tag-string tags)))
+	     ;; When text is being inserted on an invisible region
+	     ;; boundary, it can be inadvertently sucked into
+	     ;; invisibility.
+	     (unless (org-invisible-p (line-beginning-position))
+	       (org-fold-region (point) (line-end-position) nil 'outline))))
+         ;; Align tags, if any.
+         (when tags (org-align-tags))
+         (when tags-change? (run-hooks 'org-after-tags-change-hook))))))
 
 (defun org-change-tag-in-region (beg end tag off)
   "Add or remove TAG for each entry in the region.
@@ -12539,19 +12558,20 @@ (defun org-entry-put (pom property value)
         ((member property org-special-properties)
 	 (error "The %s property cannot be set with `org-entry-put'" property))
         (t
-	 (let* ((range (org-get-property-block beg 'force))
-	        (end (cdr range))
-	        (case-fold-search t))
-	   (goto-char (car range))
-	   (if (re-search-forward (org-re-property property nil t) end t)
-	       (progn (delete-region (match-beginning 0) (match-end 0))
-		      (goto-char (match-beginning 0)))
-	     (goto-char end)
-	     (insert "\n")
-	     (backward-char))
-	   (insert ":" property ":")
-	   (when value (insert " " value))
-	   (org-indent-line)))))
+         (org-fold-core-ignore-modifications
+	     (let* ((range (org-get-property-block beg 'force))
+	            (end (cdr range))
+	            (case-fold-search t))
+	       (goto-char (car range))
+	       (if (re-search-forward (org-re-property property nil t) end t)
+	           (progn (delete-region (match-beginning 0) (match-end 0))
+		          (goto-char (match-beginning 0)))
+	         (goto-char end)
+	         (insert-and-inherit "\n")
+	         (backward-char))
+	       (insert-and-inherit ":" property ":")
+	       (when value (insert-and-inherit " " value))
+	       (org-indent-line))))))
      (run-hook-with-args 'org-property-changed-functions property value))))
 
 (defun org-buffer-property-keys (&optional specials defaults columns)
@@ -13705,23 +13725,24 @@ (defun org-insert-time-stamp (time &optional with-hm inactive pre post extra)
 PRE and POST are optional strings to be inserted before and after the
 stamp.
 The command returns the inserted time stamp."
-  (let ((fmt (funcall (if with-hm 'cdr 'car) org-time-stamp-formats))
-	stamp)
-    (when inactive (setq fmt (concat "[" (substring fmt 1 -1) "]")))
-    (insert-before-markers (or pre ""))
-    (when (listp extra)
-      (setq extra (car extra))
-      (if (and (stringp extra)
-	       (string-match "\\([0-9]+\\):\\([0-9]+\\)" extra))
-	  (setq extra (format "-%02d:%02d"
-			      (string-to-number (match-string 1 extra))
-			      (string-to-number (match-string 2 extra))))
-	(setq extra nil)))
-    (when extra
-      (setq fmt (concat (substring fmt 0 -1) extra (substring fmt -1))))
-    (insert-before-markers (setq stamp (format-time-string fmt time)))
-    (insert-before-markers (or post ""))
-    (setq org-last-inserted-timestamp stamp)))
+  (org-fold-core-ignore-modifications
+      (let ((fmt (funcall (if with-hm 'cdr 'car) org-time-stamp-formats))
+	    stamp)
+        (when inactive (setq fmt (concat "[" (substring fmt 1 -1) "]")))
+        (insert-before-markers-and-inherit (or pre ""))
+        (when (listp extra)
+          (setq extra (car extra))
+          (if (and (stringp extra)
+	           (string-match "\\([0-9]+\\):\\([0-9]+\\)" extra))
+	      (setq extra (format "-%02d:%02d"
+			          (string-to-number (match-string 1 extra))
+			          (string-to-number (match-string 2 extra))))
+	    (setq extra nil)))
+        (when extra
+          (setq fmt (concat (substring fmt 0 -1) extra (substring fmt -1))))
+        (insert-before-markers-and-inherit (setq stamp (format-time-string fmt time)))
+        (insert-before-markers-and-inherit (or post ""))
+        (setq org-last-inserted-timestamp stamp))))
 
 (defun org-toggle-time-stamp-overlays ()
   "Toggle the use of custom time stamp formats."
@@ -18345,7 +18366,10 @@ (defun org--align-node-property ()
       (let ((newtext (concat (match-string 4)
 	                     (org-trim
 	                      (format org-property-format (match-string 1) (match-string 3))))))
-        (setf (buffer-substring (match-beginning 0) (match-end 0)) newtext)))))
+        ;; Do not use `replace-match' here as we want to inherit folding
+        ;; properties if inside fold.
+        (setf (buffer-substring (match-beginning 0) (match-end 0)) "")
+        (insert-and-inherit newtext)))))
 
 (defun org-indent-line ()
   "Indent line depending on context.
diff --git a/lisp/ox.el b/lisp/ox.el
index 6b68fc2da..9a8e63046 100644
--- a/lisp/ox.el
+++ b/lisp/ox.el
@@ -2588,7 +2588,9 @@ (defun org-export--generate-copy-script (buffer)
 			(or (memq var
 				  '(default-directory
 				     buffer-file-name
-				     buffer-file-coding-system))
+				     buffer-file-coding-system
+                                     ;; Needed to preserve folding state
+                                     char-property-alias-alist))
 			    (assq var bound-variables)
 			    (string-match "^\\(org-\\|orgtbl-\\)"
 					  (symbol-name var)))
diff --git a/testing/lisp/test-ob.el b/testing/lisp/test-ob.el
index 579d4df02..aa05f87a3 100644
--- a/testing/lisp/test-ob.el
+++ b/testing/lisp/test-ob.el
@@ -1557,8 +1557,8 @@ (ert-deftest test-ob/preserve-results-indentation ()
     (org-test-with-temp-text "  #+begin_src emacs-lisp\n(+ 1 1)\n  #+end_src"
       (org-babel-execute-src-block)
       (let ((case-fold-search t)) (search-forward "RESULTS"))
-      (list (org-get-indentation)
-	    (progn (forward-line) (org-get-indentation))))))
+      (list (current-indentation)
+	    (progn (forward-line) (current-indentation))))))
   (should
    (equal
     '(2 2)
@@ -1566,8 +1566,8 @@ (ert-deftest test-ob/preserve-results-indentation ()
 	"  #+name: block\n  #+begin_src emacs-lisp\n(+ 1 1)\n  #+end_src"
       (org-babel-execute-src-block)
       (let ((case-fold-search t)) (search-forward "RESULTS"))
-      (list (org-get-indentation)
-	    (progn (forward-line) (org-get-indentation))))))
+      (list (current-indentation)
+	    (progn (forward-line) (current-indentation))))))
   ;; Don't get fooled by TAB-based indentation.
   (should
    (equal
@@ -1577,8 +1577,8 @@ (ert-deftest test-ob/preserve-results-indentation ()
       (setq tab-width 4)
       (org-babel-execute-src-block)
       (let ((case-fold-search t)) (search-forward "RESULTS"))
-      (list (org-get-indentation)
-	    (progn (forward-line) (org-get-indentation))))))
+      (list (current-indentation)
+	    (progn (forward-line) (current-indentation))))))
   ;; Properly indent examplified blocks.
   (should
    (equal
diff --git a/testing/lisp/test-org.el b/testing/lisp/test-org.el
index 0a47618ca..0cc8df154 100644
--- a/testing/lisp/test-org.el
+++ b/testing/lisp/test-org.el
@@ -1522,6 +1522,7 @@ (ert-deftest test-org/meta-return ()
   (should
    (org-test-with-temp-text ":MYDRAWER:\n- a\n:END:"
      (forward-line)
+     (org-fold-reveal)
      (org-meta-return)
      (beginning-of-line)
      (looking-at "- $"))))
@@ -2943,6 +2944,7 @@ (ert-deftest test-org/custom-properties ()
    (let ((org-custom-properties '("FOO" "BAR")))
      (org-test-with-temp-text
 	 "* H\n:PROPERTIES:\n<point>:FOO: val\n:P: 1\n:BAR: baz\n:END:\n"
+       (org-fold-reveal)
        (org-toggle-custom-properties-visibility)
        (and (org-invisible-p2)
 	    (not (progn (forward-line) (org-invisible-p2)))
@@ -2963,6 +2965,7 @@ (ert-deftest test-org/custom-properties ()
    (let ((org-custom-properties '("A")))
      (org-test-with-temp-text
 	 "* H\n:PROPERTIES:\n:A: 1\n:END:\n\n:PROPERTIES:\n<point>:A: 2\n:END:"
+       (org-fold-reveal)
        (org-toggle-custom-properties-visibility)
        (org-invisible-p2)))))
 
-- 
2.35.1



-- 
Ihor Radchenko,
PhD,
Center for Advancing Materials Performance from the Nanoscale (CAMP-nano)
State Key Laboratory for Mechanical Behavior of Materials, Xi'an Jiaotong University, Xi'an, China
Email: yantar92@gmail.com, ihor_radchenko@alumni.sutd.edu.sg