[PATCH] Allow customizing commands affected by `org-fold-catch-invisible-edits' (was: Should we extend org-catch-invisible-edits to more interactive commands? (was: Catching invisible edits: problem understanding doc))

[Ihor Radchenko]

Alain.Cochard@unistra.fr writes:

> Ihor Radchenko writes on Sat 11 Feb 2023 18:22:
>
>  > We can indeed at such warning, but it will probably be not very
>  > helpful.
>
> I don't understand this.  And isn't it better to have a more accurate
> manual anyway?

Sure. But I want to implement more generic feature.
See the attached patch.

> Also, this is another instance where 'C-h v' with the cursor on
> 'org-fold-catch-invisible-edits' does not offer it right away in the
> minibuffer.  I am surprised since it does so in 9.5 (with
> 'org-catch-invisible-edit').

The variable has been moved to a different file.
C-h v not working is an Emacs bug.

>From 653005e1b383b4c7ad9086fc0b7e40d262dab744 Mon Sep 17 00:00:00 2001
Message-Id: 
<653005e1b383b4c7ad9086fc0b7e40d262dab744.1676215378.git.yantar92@posteo.net>
From: Ihor Radchenko <yantar92@posteo.net>
Date: Sun, 12 Feb 2023 18:13:36 +0300
Subject: [PATCH] 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 | 12 +++++++++---
 etc/ORG-NEWS       | 12 ++++++++++++
 lisp/org-fold.el   | 45 ++++++++++++++++++++++++++++++++++++++++++++-
 lisp/org.el        |  6 ++----
 4 files changed, 67 insertions(+), 8 deletions(-)

diff --git a/doc/org-manual.org b/doc/org-manual.org
index 2d38cf76c..2b836a026 100644
--- a/doc/org-manual.org
+++ b/doc/org-manual.org
@@ -622,11 +622,17 @@ *** Catching invisible edits
 #+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:
diff --git a/etc/ORG-NEWS b/etc/ORG-NEWS
index 87ecd77cd..b85c46758 100644
--- a/etc/ORG-NEWS
+++ b/etc/ORG-NEWS
@@ -24,6 +24,18 @@ consider 
[[https://gitlab.com/jackkamm/ob-python-mode-mode][ob-python-mode-mode]
 has been ported to.
 
 ** 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 escape in ~org-beamer-environments-extra~ for labels in Beamer export
 The escape =%l= in ~org-beamer-environments-extra~ inserts the label
 obtained from ~org-beamer--get-label~.  This is added to the default
diff --git a/lisp/org-fold.el b/lisp/org-fold.el
index 1b7ca22b0..3d86eb802 100644
--- a/lisp/org-fold.el
+++ b/lisp/org-fold.el
@@ -189,7 +189,10 @@ (defcustom org-fold-catch-invisible-edits 'smart
                  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 @@ (defcustom org-fold-catch-invisible-edits 'smart
          (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
@@ -901,6 +931,19 @@ (defun org-fold-check-before-invisible-edit (kind)
            ;; 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
diff --git a/lisp/org.el b/lisp/org.el
index 4d12084d9..8d88f83e7 100644
--- a/lisp/org.el
+++ b/lisp/org.el
@@ -4839,6 +4839,8 @@ (define-derived-mode org-mode outline-mode "Org"
   (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
@@ -16440,7 +16442,6 @@ (defun org-self-insert-command (N)
 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)))
@@ -16510,7 +16511,6 @@ (defun org-delete-backward-char (N)
 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))
@@ -16530,7 +16530,6 @@ (defun org-delete-char (N)
 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) ?|)
@@ -17944,7 +17943,6 @@ (defun org-meta-return (&optional arg)
 `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)
-- 
2.39.1

-- 
Ihor Radchenko // yantar92,
Org mode contributor,
Learn more about Org mode at <https://orgmode.org/>.
Support Org development at <https://liberapay.com/org-mode>,
or support my work at <https://liberapay.com/yantar92>