Bug: org-insert-heading-respect-content before first heading [9.4 (9.4-19-gb1de0c-elpaplus @ /home/gustavo/.emacs.d/elpa/org-plus-contrib-20201019/)]

[Gustavo Barros <gusbrs.2016@gmail.com>]

Hi All,

I just found a misbehaving of `org-insert-heading-respect-content': when 
it's called before the first heading in the buffer, it breaks the 
structure of that fist heading by inserting a new heading on the line 
the previous heading existed.

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-20201019")
  #+end_src

- Visit file =test.org= with contents:
  #+begin_src org
  ,#+title: Title


  ,* Foo
  #+end_src

- Place point between the title and the "Foo" heading, and call 
  `org-insert-heading-respect-content' with "C-RET".

- The result is:
  #+begin_src org
  ,#+title: Title


  ,* !* Foo
  #+end_src
  where "!" represents point position.

Which clearly does not "respect content" of the following heading.

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 (9.4-19-gb1de0c-elpaplus @ 
/home/gustavo/.emacs.d/elpa/org-plus-contrib-20201019/)

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-agenda-loop-over-headlines-in-active-region nil
 org-src-lang-modes '(("arduino" . arduino) ("redis" . redis) ("php" 
 . php) ("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
 )