Bug: org-toggle-link-display and org-hide-emphasis-markers [9.4 (9.4-44-g5272d9-elpaplus @ /home/gustavo/.emacs.d/elpa/org-plus-contrib-20201123/)]

[Gustavo Barros]

Hi All,

when using `org-hide-emphasis-markers', making links visible with 
`org-toggle-link-display' also unhides the emphasis markers.  I believe 
this to be unexpected behavior (it certainly is to me), but I might be 
wrong here, given that the emphasis markers are explicitly set to a 
`org-link' invisible property (which see).

An ECM to reproduce the issue is:

- Start `emacs -Q'

- Do an initial setup:
 #+begin_src emacs-lisp
 (add-to-list 'load-path "~/.emacs.d/elpa/org-plus-contrib-20201123")
 (setq org-hide-emphasis-markers t)
 #+end_src

- Open an Org buffer with contents:
 #+begin_src org
 [[https://orgmode.org/][Org mode for Emacs]]
 ,*bold*
 #+end_src
 given the settings, both the link and emphasis markers should be 
 invisible.

- Call `M-x org-toggle-link-display', see that both the link and the 
 emphasis markers are made visible.  Toggle it again, and both are 
 invisible.

As far as I dug, the reason for this behavior lies in 
`org-do-emphasis-faces' which indeed uses the `org-link' invisible 
property to hide the links (at the very end of the function):

#+begin_src emacs-lisp
(when (and org-hide-emphasis-markers
           (not (org-at-comment-p)))
 (add-text-properties (match-end 4) (match-beginning 5)
                       '(invisible org-link))
 (add-text-properties (match-beginning 3) (match-end 3)
                       '(invisible org-link)))
#+end_src

So that `org-toggle-link-display' cannot really distinguish an emphasis 
marker from an actual link when it removes `org-link' from the 
invisibility-spec.

I don't know why this is done this way in `org-do-emphasis-faces', so I 
might be missing something, but it does lead to this peculiar behavior 
of `org-toggle-link-display'.

Best regards,
Gustavo.



Emacs  : GNU Emacs 27.1 (build 1, x86_64-pc-linux-gnu, GTK+ Version 
3.24.20, cairo version 1.16.0)
of 2020-08-11
Package: Org mode version 9.4 (9.4-44-g5272d9-elpaplus @ 
/home/gustavo/.emacs.d/elpa/org-plus-contrib-20201123/)

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-mode-hook '(#[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 
		 org-eldoc-load)
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\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-emphasis-markers t
org-agenda-loop-over-headlines-in-active-region nil
org-src-lang-modes '(("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-cycle-hook '(org-cycle-hide-archived-subtrees 
org-cycle-hide-drawers org-cycle-show-empty-lines
                  org-optimize-window-after-visibility-change)
org-speed-command-hook '(org-speed-command-activate 
org-babel-speed-command-activate)
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) ("file+sys") 
		       ("file+emacs")
                       ("shell" :follow org-link--open-shell)
                       ("news" :follow
			#[514 "\301\300\302Q\"\207" ["news" browse-url 
                        ":"] 6 "\n\n(fn URL ARG)"])
                       ("mailto" :follow
			#[514 "\301\300\302Q\"\207" ["mailto" browse-url 
                        ":"] 6 "\n\n(fn URL ARG)"])
                       ("https" :follow
			#[514 "\301\300\302Q\"\207" ["https" browse-url 
                        ":"] 6 "\n\n(fn URL ARG)"])
                       ("http" :follow
			#[514 "\301\300\302Q\"\207" ["http" browse-url 
                        ":"] 6 "\n\n(fn URL ARG)"])
                       ("ftp" :follow
			#[514 "\301\300\302Q\"\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-link-elisp-confirm-function 'yes-or-no-p
)