=== modified file 'lisp/ChangeLog'
--- lisp/ChangeLog	2013-01-11 23:24:52 +0000
+++ lisp/ChangeLog	2013-01-12 07:33:28 +0000
@@ -1,3 +1,16 @@
+2013-01-12  Dmitry Gutov  <gutov@vbx>
+
+	* emacs-lisp/package.el (package-desc-kind): Get the kind from the
+	metadata plist.
+	(package-desc-meta): Return metadata plist.
+	(define-package): Store EXTRA-PROPERTIES as the 4th element of
+	the package data vector.
+	(package--add-to-archive-contents): Instead of just package kind,
+	use the 4th element of the vector for the matadata.  Include kind
+	in the metadata.
+	(describe-package-1): When the package metadata includes
+	`:homepage', display a link button for it (bug#13291).
+
 2013-01-11  Felix H. Dahlke  <fhd@ubercode.de>
 
 	* progmodes/js.el: Fix multiline declarations's indentation (bug#8576).

=== modified file 'lisp/emacs-lisp/package.el'
--- lisp/emacs-lisp/package.el	2013-01-01 09:11:05 +0000
+++ lisp/emacs-lisp/package.el	2013-01-12 07:23:54 +0000
@@ -302,12 +302,13 @@
 Each element has the form (PKG . DESC), where PKG is a package
 name (a symbol) and DESC is a vector that describes the package.
 
-The vector DESC has the form [VERSION-LIST REQS DOCSTRING].
+The vector DESC has the form [VERSION-LIST REQS DOCSTRING META].
   VERSION-LIST is a version list.
   REQS is a list of packages required by the package, each
    requirement having the form (NAME VL) where NAME is a string
    and VL is a version list.
   DOCSTRING is a brief description of the package.
+  META is a property list mapping metadata keywords to values.
 
 This variable is set automatically by `package-load-descriptor',
 called via `package-initialize'.  To change which packages are
@@ -426,6 +427,10 @@
 
 (defsubst package-desc-kind (desc)
   "Extract the kind of download from an archive package description vector."
+  (plist-get (package-desc-meta desc) :kind))
+
+(defsubst package-desc-meta (desc)
+  "Extract the metadata property list from a package description vector."
   (aref desc 3))
 
 (defun package--dir (name version)
@@ -525,7 +530,7 @@
 
 (defun define-package (name-string version-string
 				&optional docstring requirements
-				&rest _extra-properties)
+				&rest extra-properties)
   "Define a new package.
 NAME-STRING is the name of the package, as a string.
 VERSION-STRING is the version of the package, as a string.
@@ -533,8 +538,8 @@
 REQUIREMENTS is a list of dependencies on other packages.
  Each requirement is of the form (OTHER-PACKAGE OTHER-VERSION),
  where OTHER-VERSION is a string.
-
-EXTRA-PROPERTIES is currently unused."
+EXTRA-PROPERTIES is a property list mapping additional metadata
+keywords (e.g. `:homepage') to values."
   (let* ((name (intern name-string))
 	 (version (version-to-list version-string))
 	 (new-pkg-desc
@@ -545,7 +550,8 @@
 			   (list (car elt)
 				 (version-to-list (car (cdr elt)))))
 			 requirements)
-			docstring)))
+			docstring
+			extra-properties)))
 	 (old-pkg (assq name package-alist)))
     (cond
      ;; If there's no old package, just add this to `package-alist'.
@@ -853,8 +859,15 @@
 Also, add the originating archive to the end of the package vector."
   (let* ((name    (car package))
          (version (package-desc-vers (cdr package)))
+         (data    (append (cdr package) nil))
+         (ex-len  (- (length data) 3))
+         (extras  (last data ex-len))
          (entry   (cons name
-			(vconcat (cdr package) (vector archive))))
+                        (vconcat (nbutlast data ex-len)
+                                 ;; Save the kind and any following
+                                 ;; keyword-value pairs as metadata.
+                                 (vector (cons :kind extras)
+                                         archive))))
          (existing-package (assq name package-archive-contents)))
     (cond ((not existing-package)
 	   (add-to-list 'package-archive-contents entry))
@@ -1261,7 +1274,13 @@
 	  (help-insert-xref-button text 'help-package name))
 	(insert "\n")))
     (insert "    " (propertize "Summary" 'font-lock-face 'bold)
-	    ": " (if desc (package-desc-doc desc)) "\n\n")
+	    ": " (if desc (package-desc-doc desc)) "\n")
+    (let ((homepage (plist-get (package-desc-meta desc) :homepage)))
+      (when homepage
+        (insert "   " (propertize "Homepage" 'font-lock-face 'bold) ": ")
+        (help-insert-xref-button homepage 'help-url homepage)
+        (insert "\n")))
+    (insert "\n")
 
     (if built-in
 	;; For built-in packages, insert the commentary.