org.el (org-fill-paragraph-with-timestamp-nobreak-p): New function

* org.el (org-fill-paragraph-with-timestamp-nobreak-p): New
function.
(org-setup-filling): Use it to prevent breaking a timestamp
when filling a paragraph.

Thanks to William for requesting this.

lisp/org.el

@@ -20970,7 +20970,8 @@ hierarchy of headlines by UP levels before marking the subtree."
      (org-uniquify
       (append fill-nobreak-predicate
 	      '(org-fill-paragraph-separate-nobreak-p
-		org-fill-line-break-nobreak-p)))))
+		org-fill-line-break-nobreak-p
+		org-fill-paragraph-with-timestamp-nobreak-p)))))
   (org-set-local 'fill-paragraph-function 'org-fill-paragraph)
   (org-set-local 'auto-fill-inhibit-regexp nil)
   (org-set-local 'adaptive-fill-function 'org-adaptive-fill-function)
@@ -20989,6 +20990,11 @@ hierarchy of headlines by UP levels before marking the subtree."
     (skip-chars-backward "\\\\")
     (looking-at "\\\\\\\\\\($\\|[^\\\\]\\)")))
 
+(defun org-fill-paragraph-with-timestamp-nobreak-p ()
+  "Non-nil when a line break at point would insert a new item."
+  (and (org-at-timestamp-p t)
+       (not (looking-at org-ts-regexp-both))))
+
 (declare-function message-in-body-p "message" ())
 (defvar org-element--affiliated-re) ; From org-element.el
 (defvar orgtbl-line-start-regexp) ; From org-table.el