org-fold: Allow customizing commands where invisible edits are checked

* lisp/org-fold.el (org-fold-catch-invisible-edits-commands): New
custom option.
(org-fold-catch-invisible-edits): Mention the new custom option in the
docstring.
(org-fold-check-before-invisible-edit-maybe): New function checking
if edits are safe for `this-command'.
(org-fold--advice-edit-commands): New function advising the functions
with `org-fold-check-before-invisible-edit-maybe'.
* lisp/org.el (org-mode): Advice functions on Org startup.
(org-self-insert-command):
(org-delete-backward-char):
(org-delete-char):
(org-meta-return): Do not call `org-fold-check-before-invisible-edit'
and rely on the new advise mechanism instead.
* etc/ORG-NEWS (Commands affected by ~org-fold-catch-invisible-edits~
can now be customized): Announce the change.
* doc/org-manual.org (Catching invisible edits): Mention new
customization.

doc/org-manual.org

@@ -622,11 +622,17 @@ for this property are =folded=, =children=, =content=, and =all=.
 #+cindex: edits, catching invisible
 
 #+vindex: org-fold-catch-invisible-edits
+#+vindex: org-fold-catch-invisible-edits-commands
 Sometimes you may inadvertently edit an invisible part of the buffer
 and be confused on what has been edited and how to undo the mistake.
-Setting ~org-fold-catch-invisible-edits~ to non-~nil~ helps preventing
-this.  See the docstring of this option on how Org should catch
-invisible edits and process them.
+By default, Org prevents such edits for a limited set of user
+commands.  Users can control which commands are affected by
+customizing ~org-fold-catch-invisible-edits-commands~.
+
+The strategy used to decide if a given edit is dangerous is controlled
+by ~org-fold-catch-invisible-edits~.  See the docstring of this option
+on the available strategies.  Set the option to ~nil~ to disable
+catching invisible edits completely.
 
 ** Motion
 :PROPERTIES:

etc/ORG-NEWS

@@ -51,6 +51,18 @@ encounter issues, and users are advised to update to the most recent
 version of org-caldav.  See [[https://github.com/dengste/org-caldav/commit/618bf4cdc9be140ca1993901d017b7f18297f1b8][this org-caldav commit]] for more information.
 
 ** New and changed options
+*** Commands affected by ~org-fold-catch-invisible-edits~ can now be customized
+
+New user option ~org-fold-catch-invisible-edits-commands~ controls
+which commands trigger checking for invisible edits.
+
+The full list of affected commands is:
+- ~org-self-insert-command~
+- ~org-delete-backward-char~
+- ~org-delete-char~
+- ~org-meta-return~
+- ~org-return~ (not checked in earlier Org versions)
+
 *** New customization ~org-image-max-width~ limiting the displayed inline image width
 
 New custom variable ~org-image-max-width~ limits the maximum inline

lisp/org-fold.el

@@ -189,7 +189,10 @@ smart            Make point visible, and do insertion/deletion if it is
                  Never delete a previously invisible character or add in the
                  middle or right after an invisible region.  Basically, this
                  allows insertion and backward-delete right before ellipses.
-                 FIXME: maybe in this case we should not even show?"
+                 FIXME: maybe in this case we should not even show?
+
+This variable only affects commands listed in
+`org-fold-catch-invisible-edits-commands'."
   :group 'org-edit-structure
   :version "24.1"
   :type '(choice
@@ -199,6 +202,33 @@ smart            Make point visible, and do insertion/deletion if it is
 	  (const :tag "Show invisible part and do the edit" show)
 	  (const :tag "Be smart and do the right thing" smart)))
 
+(defcustom org-fold-catch-invisible-edits-commands
+  ;; We do not add non-Org commands here by default to avoid advising
+  ;; globally.  See `org-fold--advice-edit-commands'.
+  '((org-self-insert-command . insert)
+    (org-delete-backward-char . delete-backward)
+    (org-delete-char . delete)
+    (org-meta-return . insert)
+    (org-return . insert))
+  "Alist of commands where Org checks for invisible edits.
+Each element is (COMMAND . KIND), where COMMAND is symbol representing
+command as stored in `this-command' and KIND is symbol `insert',
+symbol `delete', or symbol `delete-backward'.
+
+The checks are performed around `point'.
+
+This variable must be set before loading Org in order to take effect.
+
+Also, see `org-fold-catch-invisible-edits'."
+  :group 'org-edit-structure
+  :package-version '("Org" . "9.7")
+  :type '(alist
+          :key-type symbol
+          :value-type (choice
+                       (const insert)
+                       (const delete)
+                       (const delete-backward))))
+
 ;;; Core functionality
 
 ;;; API
@@ -903,6 +933,19 @@ The detailed reaction depends on the user option
 	    ;; Don't do the edit, make the user repeat it in full visibility
 	    (user-error "Edit in invisible region aborted, repeat to confirm with text visible"))))))))
 
+(defun org-fold-check-before-invisible-edit-maybe (&rest _)
+  "Check before invisible command by `this-command'."
+  (when (derived-mode-p 'org-mode)
+    (pcase (alist-get this-command org-fold-catch-invisible-edits-commands)
+      ((pred null) nil)
+      (kind (org-fold-check-before-invisible-edit kind)))))
+
+(defun org-fold--advice-edit-commands ()
+  "Advice editing commands according to `org-fold-catch-invisible-edits-commands'.
+The advices are installed in current buffer."
+  (dolist (command (mapcar #'car org-fold-catch-invisible-edits-commands))
+    (advice-add command :before #'org-fold-check-before-invisible-edit-maybe)))
+
 (provide 'org-fold)
 
 ;;; org-fold.el ends here

lisp/org.el

@@ -4845,6 +4845,8 @@ The following commands are available:
   (add-hook 'before-change-functions 'org-before-change-function nil 'local)
   ;; Check for running clock before killing a buffer
   (add-hook 'kill-buffer-hook 'org-check-running-clock nil 'local)
+  ;; Check for invisible edits.
+  (org-fold--advice-edit-commands)
   ;; Initialize cache.
   (org-element-cache-reset)
   (when (and org-element-cache-persistent
@@ -16477,7 +16479,6 @@ either not currently on a tagged headline or on a tag."
 If the cursor is in a table looking at whitespace, the whitespace is
 overwritten, and the table is not marked as requiring realignment."
   (interactive "p")
-  (org-fold-check-before-invisible-edit 'insert)
   (cond
    ((and org-use-speed-commands
 	 (let ((kv (this-command-keys-vector)))
@@ -16549,7 +16550,6 @@ still be marked for re-alignment if the field did fill the entire column,
 because, in this case the deletion might narrow the column."
   (interactive "p")
   (save-match-data
-    (org-fold-check-before-invisible-edit 'delete-backward)
     (if (and (= N 1)
 	     (not overwrite-mode)
 	     (not (org-region-active-p))
@@ -16569,7 +16569,6 @@ still be marked for re-alignment if the field did fill the entire column,
 because, in this case the deletion might narrow the column."
   (interactive "p")
   (save-match-data
-    (org-fold-check-before-invisible-edit 'delete)
     (cond
      ((or (/= N 1)
 	  (eq (char-after) ?|)
@@ -17985,7 +17984,6 @@ Calls `org-insert-heading', `org-insert-item' or
 `org-table-wrap-region', depending on context.  When called with
 an argument, unconditionally call `org-insert-heading'."
   (interactive "P")
-  (org-fold-check-before-invisible-edit 'insert)
   (or (run-hook-with-args-until-success 'org-metareturn-hook)
       (call-interactively (cond (arg #'org-insert-heading)
 				((org-at-table-p) #'org-table-wrap-region)