Bug: org-latex--format-spec does not support documented SUBTITLE/%s substitution [9.3.4 (9.3.4-elpa @ /home/seth/.emacs.d/elpa/org-20200206/)]

[Robertson, Seth]

------------------------------------------------------------------------

org-latex-title-command does not honor the document SUBTITLE or %s
substitution, and throws an error invalid format character %s.

Investigation showed that org-latex--format-spec did not have an entry
for %s.  Making the obvious change appeared to resolve the issue:

#+BEGIN_SRC emacs-lisp
--- ox-latex.el~        2020-02-07 13:59:34.804141887 -0500
+++ ox-latex.el 2020-02-07 14:00:18.836895973 -0500
@@ -1586,6 +1586,7 @@
                        lang))))
     `((?a . ,(org-export-data (plist-get info :author) info))
       (?t . ,(org-export-data (plist-get info :title) info))
+      (?s . ,(org-export-data (plist-get info :subtitle) info))
       (?k . ,(org-export-data (org-latex--wrap-latex-math-block
                               (plist-get info :keywords) info)
                              info))
#+END_SRC



Emacs  : GNU Emacs 26.3 (build 1, x86_64-redhat-linux-gnu, GTK+ Version 3.24.13)
 of 2019-12-10
Package: Org mode version 9.3.4 (9.3.4-elpa @ 
/home/srobertson/.emacs.d/elpa/org-20200206/)