From 20b33106cdd108fd3212e5fef135a55e25ede4a4 Mon Sep 17 00:00:00 2001
From: Ihor Radchenko <yantar92@posteo.net>
Date: Wed, 22 Mar 2023 16:06:34 +0100
Subject: [PATCH] org-element-headline-parser: Fix empty headings with tags

* lisp/org-element.el (org-element-headline-parser): Allow empty title
with tags.  Do not consider space after COMMENT to be a part of title.
*
testing/lisp/test-org-element.el (test-org-element/headline-todo-keyword):
Add tests.

Reported-by: Leo Butler <Leo.Butler@umanitoba.ca>
Link: https://orgmode.org/list/87zg8t4zgo.fsf@localhost
---
 lisp/org-element.el              | 15 ++++++---------
 testing/lisp/test-org-element.el | 10 +++++++++-
 2 files changed, 15 insertions(+), 10 deletions(-)

diff --git a/lisp/org-element.el b/lisp/org-element.el
index d61a7efb2..357ad5596 100644
--- a/lisp/org-element.el
+++ b/lisp/org-element.el
@@ -1114,16 +1114,13 @@ Assume point is at beginning of the headline."
 				 (aref (match-string 0) 2))))
 	   (commentedp
 	    (and (let ((case-fold-search nil))
-                   (looking-at org-element-comment-string))
-		 (goto-char (match-end 0))
-                 (when (looking-at-p "\\(?:[ \t]\\|$\\)")
-                   (point))))
-	   (title-start (prog1 (point)
-                          (unless (or todo priority commentedp)
-                            ;; Headline like "* :tag:"
-                            (skip-chars-backward " \t"))))
+                   (looking-at (concat org-element-comment-string "\\(?: \\|$\\)")))
+                 (prog1 t
+		   (goto-char (match-end 0))
+                   (skip-chars-forward " \t"))))
+	   (title-start (point))
 	   (tags (when (re-search-forward
-			"[ \t]+\\(:[[:alnum:]_@#%:]+:\\)[ \t]*$"
+			"\\(:[[:alnum:]_@#%:]+:\\)[ \t]*$"
 			(line-end-position)
 			'move)
 		   (goto-char (match-beginning 0))
diff --git a/testing/lisp/test-org-element.el b/testing/lisp/test-org-element.el
index e2cdadbd1..6f95b0f0a 100644
--- a/testing/lisp/test-org-element.el
+++ b/testing/lisp/test-org-element.el
@@ -1209,7 +1209,15 @@ Some other text
       (should-not (org-element-property :todo-keyword (org-element-at-point)))))
   (org-test-with-temp-text "* TODO"
     (let ((org-todo-keywords '((sequence "TODO" "DONE"))))
-      (should (org-element-property :todo-keyword (org-element-at-point))))))
+      (should (org-element-property :todo-keyword (org-element-at-point)))))
+  (org-test-with-temp-text "* :tag:"
+    (should (member "tag" (org-element-property :tags (org-element-at-point)))))
+  (org-test-with-temp-text "* COMMENT"
+    (should (org-element-property :commentedp (org-element-at-point))))
+  (org-test-with-temp-text "* COMMENT title"
+    (should (equal "title" (org-element-property :raw-value (org-element-at-point)))))
+  (org-test-with-temp-text "* COMMENT:tag:"
+    (should-not (org-element-property :commentedp (org-element-at-point)))))
 
 (ert-deftest test-org-element/headline-comment-keyword ()
   "Test COMMENT keyword recognition."