Bug: org-catch-invisible-edits doesn't actually catch most deletions [9.4 (9.4-41-g9bb930-elpaplus @ /home/omarantolin/.emacs.d/elpa/org-plus-contrib-20201116/)]

[Omar Antolín Camarena]

Remember to cover the basics, that is, what you expected to happen and
what in fact did happen.  You don't know how to make a good report?  See

     https://orgmode.org/manual/Feedback.html#Feedback

Your bug report will be posted to the Org mailing list.
------------------------------------------------------------------------

Setting org-catch-invisible-edits to 'error does catch org-delete-backward-char 
(bound to <backspace> by default), but it doesn't catch backward-kill-word 
(<C-backspace>), or kill-word with argument -1 (M-- M-d), or backward-kill-sexp 
(ESC <C-backspace>).

Steps to reproduce:

1. Create an org file with the following 3 lines:

* Stop, hammer time!
You can't touch this
* Break it down!

2. Run emacs -Q and visit the file.

3. M-: (setq org-catch-invisible-edits 'error)

4. Make sure the first headline is folded and place point after the ellipsis.

5. Now you can try any of the commands mentioned in the first paragraph.

The org-catch-invisible-edits will successfully block you from using 
<backspace>, but any of the other command I mentioned will silently delete the 
word "this". Because of the variable's name, I would expect all these commands 
to be blocked.

Maybe technically this isn't a bug, since the docstring for 
org-catch-invisible-edits only says: "Check if in invisible region before 
inserting or deleting a character." So you can argue it only promises to block 
deletion if you attempt it one character at a time, and if you try to delete a 
word, the docstring doesn't promise to stop you.

I'd suggest that naming the variable org-catch-invisible-edits strongly 
suggests it should catch all deletions in the invisible text and that the 
current behavior is misleading.

Emacs  : GNU Emacs 28.0.50 (build 1, x86_64-pc-linux-gnu, GTK+ Version 3.24.5, 
cairo version 1.16.0)
 of 2020-10-13, unofficial emacs-snapshot build: http://emacs.ganneff.de/, git 
commit 8d241e8840fdb02dcfce52425626dd8f2125e51a
Package: Org mode version 9.4 (9.4-41-g9bb930-elpaplus @ 
/home/omarantolin/.emacs.d/elpa/org-plus-contrib-20201116/)

current state:
==============
(setq
 org-src-mode-hook '(org-src-babel-configure-edit-buffer
                     org-src-mode-configure-edit-buffer)
 org-link-shell-confirm-function 'yes-or-no-p
 org-metadown-hook '(org-babel-pop-to-session-maybe)
 org-clock-out-hook '(org-clock-remove-empty-clock-drawer)
 org-refile-targets '((nil :maxlevel . 2) ("~/Notes/Notes.org" :maxlevel . 2)
                      ("~/Notes/Someday.org" :level . 0)
                      ("~/Notes/Daily.org" :level . 3))
 org-pretty-entities t
 org-capture-bookmark nil
 org-latex-default-packages-alist '(("AUTO" "inputenc" t ("pdflatex"))
                                    ("" "graphicx" t) ("" "grffile" t)
                                    ("" "longtable" nil) ("" "wrapfig" nil)
                                    ("" "rotating" nil) ("normalem" "ulem" t)
                                    ("" "amsmath" t) ("" "amssymb" t)
                                    ("" "capt-of" nil) ("" "hyperref" nil))
 org-special-ctrl-a/e t
 org-agenda-files '("~/Notes/Refile.org" "~/Notes/Daily.org"
                    "~/Notes/Alumnos.org" "~/Notes/Someday.org")
 org-mode-hook '(#[0 "\301\211%10\207"
                   [imenu-create-index-function org-imenu-get-tree] 2]
                 #[0 "\300\301\302\303\304$\207"
                   [add-hook change-major-mode-hook org-show-all append local]
                   5]
                 #[0 "\300\301\302\303\304$\207"
                   [add-hook change-major-mode-hook org-babel-show-result-all
                    append local]
                   5]
                 org-babel-result-hide-spec org-babel-hide-all-hashes
                 ediff-with-org-show-all turn-on-org-cdlatex beginend-org-mode
                 org-eldoc-load)
 org-outline-path-complete-in-steps nil
 org-archive-hook '(org-attach-archive-delete-maybe)
 org-confirm-elisp-link-function 'yes-or-no-p
 org-agenda-before-write-hook '(org-agenda-add-entry-text)
 org-metaup-hook '(org-babel-load-in-session-maybe)
 org-bibtex-headline-format-function #[257 "\300%1\236A\207" [:title] 3 
"\n\n(fn ENTRY)"]
 org-babel-pre-tangle-hook '(save-buffer)
 org-tab-first-hook '(org-babel-hide-result-toggle-maybe
                      org-babel-header-arg-expand)
 org-hide-leading-stars t
 org-hide-emphasis-markers t
 org-highlight-latex-and-related '(latex script entities)
 org-ellipsis "…"
 org-agenda-loop-over-headlines-in-active-region nil
 org-src-lang-modes '(("latex-macros" . latex) ("inline-js" . javascript)
                      ("redis" . redis) ("php" . php) ("arduino" . arduino)
                      ("C" . c) ("C++" . c++) ("asymptote" . asy)
                      ("bash" . sh) ("beamer" . latex) ("calc" . fundamental)
                      ("cpp" . c++) ("ditaa" . artist) ("dot" . fundamental)
                      ("elisp" . emacs-lisp) ("ocaml" . tuareg)
                      ("screen" . shell-script) ("shell" . sh)
                      ("sqlite" . sql))
 org-occur-hook '(org-first-headline-recenter)
 org-agenda-mode-hook '(beginend-org-agenda-mode)
 org-structure-template-alist '(("a" . "export ascii") ("c" . "center")
                                ("C" . "comment") ("e" . "example")
                                ("E" . "export") ("h" . "export html")
                                ("l" . "export latex") ("q" . "quote")
                                ("s" . "src") ("v" . "verse")
                                ("thm" . "theorem") ("pf" . "proof")
                                ("lem" . "lemma") ("cor" . "corollary")
                                ("def" . "definition") ("rem" . "remark")
                                ("exer" . "exercise") ("prop" . "proposition")
                                ("el" . "src emacs-lisp"))
 org-cycle-hook '(org-cycle-hide-archived-subtrees org-cycle-hide-drawers
                  org-cycle-show-empty-lines
                  org-optimize-window-after-visibility-change)
 org-todo-keywords '((sequence "TODO" "|" "DONE" "NOPE") (type "WAIT"))
 org-support-shift-select t
 org-speed-command-hook '(org-speed-command-activate
                          org-babel-speed-command-activate)
 org-refile-allow-creating-parent-nodes 'confirm
 org-refile-use-outline-path 'file
 org-export-before-parsing-hook '(org-attach-expand-links)
 org-confirm-shell-link-function 'yes-or-no-p
 org-link-parameters '(("attachment" :follow org-attach-follow :complete
                        org-attach-complete-link)
                       ("id" :follow org-id-open)
                       ("eww" :follow org-eww-open :store org-eww-store-link)
                       ("rmail" :follow org-rmail-open :store
                        org-rmail-store-link)
                       ("mhe" :follow org-mhe-open :store org-mhe-store-link)
                       ("irc" :follow org-irc-visit :store org-irc-store-link
                        :export org-irc-export)
                       ("info" :follow org-info-open :export org-info-export
                        :store org-info-store-link)
                       ("gnus" :follow org-gnus-open :store
                        org-gnus-store-link)
                       ("docview" :follow org-docview-open :export
                        org-docview-export :store org-docview-store-link)
                       ("bibtex" :follow org-bibtex-open :store
                        org-bibtex-store-link)
                       ("bbdb" :follow org-bbdb-open :export org-bbdb-export
                        :complete org-bbdb-complete-link :store
                        org-bbdb-store-link)
                       ("w3m" :store org-w3m-store-link)
                       ("cite" :follow org-bibtex-goto-citation :export nil)
                       ("org-title" :store store-org-title-link) ("file+sys")
                       ("file+emacs") ("shell" :follow org-link--open-shell)
                       ("news" :follow
                        #[514 "\301\300\302%4Q%2\"\207"
                          ["news" browse-url ":"] 6 "\n\n(fn URL ARG)"]
                        )
                       ("mailto" :follow
                        #[514 "\301\300\302%4Q%2\"\207"
                          ["mailto" browse-url ":"] 6 "\n\n(fn URL ARG)"]
                        )
                       ("https" :follow
                        #[514 "\301\300\302%4Q%2\"\207"
                          ["https" browse-url ":"] 6 "\n\n(fn URL ARG)"]
                        )
                       ("http" :follow
                        #[514 "\301\300\302%4Q%2\"\207"
                          ["http" browse-url ":"] 6 "\n\n(fn URL ARG)"]
                        )
                       ("ftp" :follow
                        #[514 "\301\300\302%4Q%2\"\207" ["ftp" browse-url ":"]
                          6 "\n\n(fn URL ARG)"]
                        )
                       ("help" :follow org-link--open-help)
                       ("file" :complete org-link-complete-file)
                       ("elisp" :follow org-link--open-elisp)
                       ("doi" :follow org-link--open-doi))
 org-capture-templates '(("s" "Someday" entry (file "Someday.org") "* %?\n")
                         ("d" "Daily" entry (file+olp+datetree "Daily.org")
                          "* TODO %?\n")
                         ("r" "Refile" entry (file "Refile.org") "* %?\n")
                         ("j" "Journal entry" plain
                          (file+olp+datetree "Journal.org"))
                         ("e" "Emacs templates")
                         ("ei" "Idea" entry
                          (file+olp "Editors/Emacs.org" "Ideas") "* %?\n")
                         ("et" "Tip" entry
                          (file+olp "Editors/Emacs.org" "Tips") "* %?\n")
                         ("eq" "Question" entry
                          (file+olp "Editors/Emacs.org" "Questions") "* %?\n")
                         ("ep" "Package" entry
                          (file+olp "Editors/Emacs.org" "Packages") "* %?\n")
                         )
 org-link-elisp-confirm-function 'yes-or-no-p
 outline-mode-hook '(beginend-outline-mode)
 org-latex-packages-alist '(("AUTO" "babel" t ("pdflatex")))
 org-confirm-babel-evaluate nil
 org-directory "~/Notes"
 org-preview-latex-image-directory "~/.cache/ltximg/"
 )