org-bibtex-yank: Allow to populate existing item

Align with `org-bibtex-create'.

* lisp/ol-bibtex.el (org-bibtex-write):
* lisp/ol-bibtex.el (org-bibtex-yank): New optional argument
UPDATE-HEADING to update heading at point instead of creating a new
heading.
(org-bibtex-create): Rename NONEW argument to UPDATE-HEADING.
* etc/ORG-NEWS (~org-bibtex-yank~ accepts a prefix argument):
(New optional argument =UPDATE-HEADING= for ~org-bibtex-yank~):
Announce the change.

Link: https://list.orgmode.org/orgmode/4868155.GXAFRqVoOG@gt1/

etc/ORG-NEWS

@@ -928,6 +928,11 @@ properties, links to headlines in the file can also be made more
 robust by using the file id instead of the file path.
 
 ** New features
+*** ~org-bibtex-yank~ accepts a prefix argument
+
+When called with a prefix argument, ~org-bibtex-yank~ adds data to the
+headline of the entry at point instead of creating a new one.
+
 *** =ob-plantuml.el=: Support tikz file format output
 
 =ob-plantuml.el= now output =tikz= :file format via
@@ -1127,6 +1132,11 @@ The same can be done via startup options:
 : #+STARTUP: fnanon
 
 ** New functions and changes in function arguments
+*** New optional argument =UPDATE-HEADING= for ~org-bibtex-yank~
+
+When the new argument is non-nil, add data to the headline of the
+entry at point.
+
 *** New API functions to store data within ~org-element-cache~
 
 Elisp programs can now store data inside Org element cache.

lisp/ol-bibtex.el

@@ -640,22 +640,23 @@ With prefix argument OPTIONAL also prompt for optional fields."
   "Return headline text according to ENTRY title."
   (cdr (assq :title entry)))
 
-(defun org-bibtex-create (&optional arg nonew)
+(defun org-bibtex-create (&optional arg update-heading)
   "Create a new entry at the given level.
-With a prefix arg, query for optional fields as well.
+With a prefix ARG, query for optional fields as well.
-If nonew is t, add data to the headline of the entry at point."
+If UPDATE-HEADING is non-nil, add data to the headline of the entry at
+point."
   (interactive "P")
   (let* ((type (completing-read
 		"Type: " (mapcar (lambda (type)
 				   (substring (symbol-name (car type)) 1))
 				 org-bibtex-types)
-		nil nil (when nonew
+		nil nil (when update-heading
-			  (org-bibtex-get org-bibtex-type-property-name))))
+		      (org-bibtex-get org-bibtex-type-property-name))))
 	 (type (if (keywordp type) type (intern (concat ":" type))))
-	 (org-bibtex-treat-headline-as-title (if nonew nil t)))
+	 (org-bibtex-treat-headline-as-title (if update-heading nil t)))
     (unless (assoc type org-bibtex-types)
       (error "Type:%s is not known" type))
-    (if nonew
+    (if update-heading
 	(org-back-to-heading)
       (org-insert-heading)
       (let ((title (org-bibtex-ask :title)))
@@ -722,29 +723,32 @@ Return the number of saved entries."
   (interactive "fFile: ")
   (org-bibtex-read-buffer (find-file-noselect file 'nowarn 'rawfile)))
 
-(defun org-bibtex-write (&optional noindent)
+(defun org-bibtex-write (&optional noindent update-heading)
   "Insert a heading built from the first element of `org-bibtex-entries'.
 When optional argument NOINDENT is non-nil, do not indent the properties
-drawer."
+drawer.  If UPDATE-HEADING is non-nil, add data to the headline of the
+entry at point."
   (interactive)
   (unless org-bibtex-entries
     (error "No entries in `org-bibtex-entries'"))
   (let* ((entry (pop org-bibtex-entries))
 	 (org-special-properties nil) ; avoids errors with `org-entry-put'
 	 (val (lambda (field) (cdr (assoc field entry))))
-	 (togtag (lambda (tag) (org-toggle-tag tag 'on))))
+	 (togtag (lambda (tag) (org-toggle-tag tag 'on)))
-    (org-insert-heading)
+         (insert-raw (not update-heading)))
-    (insert (funcall org-bibtex-headline-format-function entry))
+    (unless update-heading
-    (insert "\n:PROPERTIES:\n")
+      (org-insert-heading)
-    (org-bibtex-put "TITLE" (funcall val :title) 'insert)
+      (insert (funcall org-bibtex-headline-format-function entry))
+      (insert "\n:PROPERTIES:\n"))
+    (org-bibtex-put "TITLE" (funcall val :title) insert-raw)
     (org-bibtex-put org-bibtex-type-property-name
 		    (downcase (funcall val :type))
-                    'insert)
+                    insert-raw)
     (dolist (pair entry)
       (pcase (car pair)
 	(:title    nil)
 	(:type     nil)
-	(:key      (org-bibtex-put org-bibtex-key-property (cdr pair) 'insert))
+	(:key      (org-bibtex-put org-bibtex-key-property (cdr pair) insert-raw))
 	(:keywords (if org-bibtex-tags-are-keywords
 		       (dolist (kw (split-string (cdr pair) ", *"))
 			 (funcall
@@ -752,25 +756,28 @@ drawer."
 			  (replace-regexp-in-string
 			   "[^[:alnum:]_@#%]" ""
 			   (replace-regexp-in-string "[ \t]+" "_" kw))))
-		     (org-bibtex-put (car pair) (cdr pair) 'insert)))
+		     (org-bibtex-put (car pair) (cdr pair) insert-raw)))
-	(_ (org-bibtex-put (car pair) (cdr pair) 'insert))))
+	(_ (org-bibtex-put (car pair) (cdr pair) insert-raw))))
-    (insert ":END:\n")
+    (unless update-heading
+      (insert ":END:\n"))
     (mapc togtag org-bibtex-tags)
     (unless noindent
       (org-indent-region
        (save-excursion (org-back-to-heading t) (point))
        (point)))))
 
-(defun org-bibtex-yank ()
+(defun org-bibtex-yank (&optional update-heading)
-  "If kill ring holds a bibtex entry yank it as an Org headline."
+  "If kill ring holds a bibtex entry yank it as an Org headline.
-  (interactive)
+When called with non-nil prefix argument UPDATE-HEADING, add data to the
+headline of the entry at point."
+  (interactive "P")
   (let (entry)
     (with-temp-buffer
       (yank 1)
       (bibtex-mode)
       (setf entry (org-bibtex-read)))
     (if entry
-	(org-bibtex-write)
+	(org-bibtex-write nil update-heading)
       (error "Yanked text does not appear to contain a BibTeX entry"))))
 
 (defun org-bibtex-import-from-file (file)