From cc66884f2836bee1203d06618828c0339ea2e4e2 Mon Sep 17 00:00:00 2001
From: Matt Lundin <mdl@imapmail.org>
Date: Thu, 26 Nov 2015 19:22:00 -0600
Subject: [PATCH] Speed up publishing by caching included file data

* lisp/ox-publish.el: (org-publish-cache-get-included-files): New function
  (org-publish-org-to): Use new function
  (org-publish-cache-file-needs-publishing): Use cache instead of
  visiting every file in a project.

Org-publish can now quickly determine a) whether an org source includes
other files (either via #+INCLUDE or #+SETUPFILE) and b) whether those
files have changed. This speeds up the publishing process and makes
tracking of changes in included files more reliable.
---
 lisp/ox-publish.el | 70 ++++++++++++++++++++++++++++++------------------------
 1 file changed, 39 insertions(+), 31 deletions(-)

diff --git a/lisp/ox-publish.el b/lisp/ox-publish.el
index 90f307c..02eb06d 100644
--- a/lisp/ox-publish.el
+++ b/lisp/ox-publish.el
@@ -574,6 +574,7 @@ Return output file name."
 	     (let ((output-file
 		    (org-export-output-file-name extension nil pub-dir))
 		   (body-p (plist-get plist :body-only)))
+	       (when org-publish-cache (org-publish-cache-get-included-files))
 	       (org-export-to-file backend output-file
 		 nil nil nil body-p
 		 ;; Add `org-publish--collect-references' and
@@ -1221,42 +1222,49 @@ If FREE-CACHE, empty the cache."
 (defun org-publish-cache-file-needs-publishing
     (filename &optional pub-dir pub-func _base-dir)
   "Check the timestamp of the last publishing of FILENAME.
-Return non-nil if the file needs publishing.  Also check if
-any included files have been more recently published, so that
-the file including them will be republished as well."
+Return non-nil if the file needs publishing.  Also use the cache
+to check if any included files have changed, so that the file
+including them will be republished."
   (unless org-publish-cache
     (error
      "`org-publish-cache-file-needs-publishing' called, but no cache present"))
-  (let* ((case-fold-search t)
-	 (key (org-publish-timestamp-filename filename pub-dir pub-func))
+  (let* ((key (org-publish-timestamp-filename filename pub-dir pub-func))
 	 (pstamp (org-publish-cache-get key))
-	 (org-inhibit-startup t)
-	 (visiting (find-buffer-visiting filename))
-	 included-files-ctime buf)
-    (when (equal (file-name-extension filename) "org")
-      (setq buf (find-file (expand-file-name filename)))
-      (with-current-buffer buf
-	(goto-char (point-min))
-	(while (re-search-forward "^[ \t]*#\\+INCLUDE:" nil t)
-	  (let* ((element (org-element-at-point))
-		 (included-file
-		  (and (eq (org-element-type element) 'keyword)
-		       (let ((value (org-element-property :value element)))
-			 (and value
-			      (string-match "^\\(\".+?\"\\|\\S-+\\)" value)
-			      ;; Ignore search suffix.
-			      (car (split-string
-				    (org-remove-double-quotes
-				     (match-string 1 value)))))))))
-	    (when included-file
-	      (push (org-publish-cache-ctime-of-src
-		     (expand-file-name included-file))
-		    included-files-ctime)))))
-      (unless visiting (kill-buffer buf)))
+	 (ctime (when pstamp (org-publish-cache-ctime-of-src filename))))
     (or (null pstamp)
-	(let ((ctime (org-publish-cache-ctime-of-src filename)))
-	  (or (< pstamp ctime)
-	      (cl-some (lambda (ct) (< ctime ct)) included-files-ctime))))))
+	(< pstamp ctime)
+	(cl-some (lambda (incl)
+		   ;; See if cached time is before modification time.
+		   (< (cdr incl)
+		      (org-publish-cache-ctime-of-src (car incl))))
+	  (org-publish-cache-get-file-property filename :includes)))))
+
+(defun org-publish-cache-get-included-files ()
+  "Get data about included files in current buffer.
+Store file names and modification times in cache. Also store data
+about setupfiles."
+  (let ((case-fold-search t)
+	included)
+    (save-excursion
+      (goto-char (point-min))
+      (while (re-search-forward "^[ \t]*#\\+\\(INCLUDE\\|SETUPFILE\\):" nil t)
+	(let* ((element (org-element-at-point))
+	       (included-file
+		(and (eq (org-element-type element) 'keyword)
+		     (let ((value (org-element-property :value element)))
+		       (and value
+			    (string-match "^\\(\".+?\"\\|\\S-+\\)" value)
+			    ;; Ignore search suffix.
+			    (car (split-string
+				  (org-remove-double-quotes
+				   (match-string 1 value)))))))))
+	  (when included-file
+	    (let ((iname (expand-file-name included-file)))
+	      (push (cons iname (org-publish-cache-ctime-of-src
+				 (expand-file-name iname)))
+		    included))))))
+    (org-publish-cache-set-file-property (buffer-file-name)
+					 :includes included)))
 
 (defun org-publish-cache-set-file-property
   (filename property value &optional project-name)
-- 
2.6.2