ox-texinfo:: Always provide a @direntry

Until now @dircategory/@direntry entries were added only if
both TEXINFO_DIR_CATEGORY and TEXINFO_DIR_TITLE were set.
And the setting of TEXINFO_DIR_TITLE had to be careful to
provide exactly the right syntax.

This patch changes various things in this regard:
- Always generate a @dircategory/@direntry.
- Default TEXINFO_DIR_CATEGORY to "Misc".
- Use the document title by default if TEXINFO_DIR_DESC is missing.
- Rename TEXINFO_DIR_TITLE to TEXINFO_DIR_NAME.
- Use the filename by default when TEXINFO_DIR_NAME is missing.
- Try and make it harder to provide a direntry that does not
  have the right format or refers to a different filename than
  the one we're outputting to.

* lisp/ox-texinfo.el (texinfo): Add entry for TEXINFO_DIR_NAME.
(org-texinfo-template): Use sane defaults for `@direntry` and `@dircategory`.

* doc/org-manual.org (Texinfo specific export settings): Adjust accordingly.
(Info directory file, A Texinfo example, Export Setup): Update examples
to use the new syntax.
* etc/ORG-NEWS (Version 9.7 / New features): Add entry.

doc/org-manual.org

@@ -15718,17 +15718,26 @@ the general options (see [[*Export Settings]]).
 - =TEXINFO_DIR_CATEGORY= ::
 
   #+cindex: @samp{TEXINFO_DIR_CATEGORY}, keyword
-  The directory category of the document.
+  The directory category of the document.  Defaults to ~Misc~.
 
-- =TEXINFO_DIR_TITLE= ::
+- =TEXINFO_DIR_NAME= ::
 
-  #+cindex: @samp{TEXINFO_DIR_TITLE}, keyword
+  #+cindex: @samp{TEXINFO_DIR_NAME}, keyword
-  The directory title of the document.
+  The directory name of the document.
+  This is the short name under which the ~m~ command will find your
+  manual in the main Info directory.  It defaults to the base name of
+  the Texinfo file.
+
+  The full form of the Texinfo entry is ~* DIRNAME: NODE.~ where ~NODE~
+  is usually just ~(FILENAME)~.  Normally this option only provides the
+ ~DIRNAME~ part, but if you need more control, it can also be the full
+  entry (recognized by the presence of parentheses or a leading ~* ~).
 
 - =TEXINFO_DIR_DESC= ::
 
   #+cindex: @samp{TEXINFO_DIR_DESC}, keyword
   The directory description of the document.
+  Defaults to the title of the document.
 
 - =TEXINFO_PRINTED_TITLE= ::
 
@@ -15812,11 +15821,11 @@ Copyright information is printed on the back of the title page.
 #+cindex: @code{install-info}, in Texinfo export
 
 #+cindex: @samp{TEXINFO_DIR_CATEGORY}, keyword
-#+cindex: @samp{TEXINFO_DIR_TITLE}, keyword
+#+cindex: @samp{TEXINFO_DIR_NAME}, keyword
 #+cindex: @samp{TEXINFO_DIR_DESC}, keyword
 The end result of the Texinfo export process is the creation of an
 Info file.  This Info file's metadata has variables for category,
-title, and description: =TEXINFO_DIR_CATEGORY=, =TEXINFO_DIR_TITLE=,
+title, and description: =TEXINFO_DIR_CATEGORY=, =TEXINFO_DIR_NAME=,
 and =TEXINFO_DIR_DESC= keywords that establish where in the Info
 hierarchy the file fits.
 
@@ -15824,7 +15833,7 @@ Here is an example that writes to the Info directory file:
 
 #+begin_example
 ,#+TEXINFO_DIR_CATEGORY: Emacs
-,#+TEXINFO_DIR_TITLE: Org Mode: (org)
+,#+TEXINFO_DIR_NAME: Org Mode
 ,#+TEXINFO_DIR_DESC: Outline-based notes management and organizer
 #+end_example
 
@@ -16232,7 +16241,7 @@ Texinfo code.
 ,#+TEXINFO_HEADER: @syncodeindex pg cp
 
 ,#+TEXINFO_DIR_CATEGORY: Texinfo documentation system
-,#+TEXINFO_DIR_TITLE: sample: (sample)
+,#+TEXINFO_DIR_NAME: sample
 ,#+TEXINFO_DIR_DESC: Invoking sample
 
 ,#+TEXINFO_PRINTED_TITLE: GNU Sample
@@ -22924,7 +22933,7 @@ modify this GNU manual."
 #+export_file_name: org.texi
 
 #+texinfo_dir_category: Emacs editing modes
-#+texinfo_dir_title: Org Mode: (org)
+#+texinfo_dir_name: Org Mode: (org)
 #+texinfo_dir_desc: Outline-based notes management and organizer
 
 * Footnotes

etc/ORG-NEWS

@@ -1141,6 +1141,13 @@ anonymous footnotes automatically with ~org-footnote-new~.
 The same can be done via startup options:
 : #+STARTUP: fnanon
 
+*** ox-texinfo always generates a ~@direntry~
+We use defaults based on the file name and title of the document, and
+place the entry in the ~Misc~ category if ~TEXINFO_DIR_CATEGORY~ is missing.
+
+=TEXINFO_DIR_TITLE= is renamed to =TEXINFO_DIR_NAME=.
+The old name is obsolete.
+
 ** New functions and changes in function arguments
 *** New optional argument =UPDATE-HEADING= for ~org-bibtex-yank~
 

lisp/ox-texinfo.el

@@ -110,7 +110,8 @@
     (:subtitle "SUBTITLE" nil nil parse)
     (:subauthor "SUBAUTHOR" nil nil newline)
     (:texinfo-dircat "TEXINFO_DIR_CATEGORY" nil nil t)
-    (:texinfo-dirtitle "TEXINFO_DIR_TITLE" nil nil t)
+    (:texinfo-dirtitle "TEXINFO_DIR_TITLE" nil nil t) ;Obsolete.
+    (:texinfo-dirname "TEXINFO_DIR_NAME" nil nil t)
     (:texinfo-dirdesc "TEXINFO_DIR_DESC" nil nil t)
     (:texinfo-printed-title "TEXINFO_PRINTED_TITLE" nil nil t)
     ;; Other variables.
@@ -796,25 +797,49 @@ holding export options."
 	  (format "@copying\n%s@end copying\n\n"
 		  (org-element-normalize-string
 		   (org-export-data copying info))))
-     ;; Info directory information.  Only supply if both title and
+     (let* ((dircat (or (plist-get info :texinfo-dircat) "Misc"))
-     ;; category are provided.
+	    (file (or (org-strip-quotes (plist-get info :texinfo-filename))
-     (let ((dircat (plist-get info :texinfo-dircat))
+		    (plist-get info :output-file)))
-	   (dirtitle
+	    (file (if file (file-name-sans-extension file)))
-	    (let ((title (plist-get info :texinfo-dirtitle)))
+	    (dn (or (plist-get info :texinfo-dirname)
-	      (and title
+	            (plist-get info :texinfo-dirtitle))) ;Obsolete name.
-		   (string-match "^\\(?:\\* \\)?\\(.*?\\)\\(\\.\\)?$" title)
+	    ;; Strip any terminating `.' from `dn'.
-		   (format "* %s." (match-string 1 title))))))
+	    (dn (if (and dn (string-match "\\.\\'" dn)) (substring dn 0 -1) dn))
-       (when (and dircat dirtitle)
+	    ;; The direntry we need to produce has the shape:
+	    ;;     * DIRNAME: NODE.   DESCRIPTION.
+	    ;; where NODE is usually just `(FILENAME)', and where
+	    ;; `* FILENAME.' is a shorthand for `* FILENAME: (FILENAME).'
+	    (dirname
+             (cond
+              ((and dn (string-match
+                        (eval-when-compile
+                          (concat "\\`\\(?:"
+                                  "\\* \\(?1:.*\\)" ;Starts with `* ' or
+                                  "\\|\\(?1:.*(.*).*\\)" ;contains parens.
+                                  "\\)\\'"))
+                        dn))
+               ;; When users provide a `dn' that looks like a complete
+               ;; `* DIRNAME: (FILENAME).' thingy, we just trust them to
+               ;; provide something valid (just making sure it starts
+               ;; with `* ' and ends with `.').
+               (format "* %s." (match-string 1 dn)))
+              ;; `dn' is presumed to be just the DIRNAME part, so generate
+              ;; either `* DIRNAME: (FILENAME).' or `* FILENAME.', whichever
+              ;; is shortest.
+              ((and dn (not (equal dn file)))
+               (format "* %s: (%s)." dn (or file dn)))
+              (t (format "* %s." file)))))
        (concat "@dircategory " dircat "\n"
 	       "@direntry\n"
 	       (let ((dirdesc
-			(let ((desc (plist-get info :texinfo-dirdesc)))
+		      (let ((desc (or (plist-get info :texinfo-dirdesc)
+			              title)))
 			(cond ((not desc) nil)
 			      ((string-suffix-p "." desc) desc)
 			      (t (concat desc "."))))))
-		   (if dirdesc (format "%-23s %s" dirtitle dirdesc) dirtitle))
+		 (if dirdesc (format "%-23s %s" dirname dirdesc) dirname))
 	       "\n"
-		 "@end direntry\n\n")))
+	       "@end direntry\n\n"))
      ;; Title
      "@finalout\n"
      "@titlepage\n"