Preview fixes: different method of showing previews for published posts, now uses the proper templates. Fixes #8052

git-svn-id: http://svn.automattic.com/wordpress/trunk@9509 1a063a9b-81f0-0310-95a4-ce76da25c4cd

wp-admin/includes/post.php

@@ -998,7 +998,7 @@ function wp_create_post_autosave( $post_id ) {
  * @uses current_user_can()
  * @uses wp_create_post_autosave()
  * 
- * @return int|object the saved post id or wp_error object
+ * @return str URL to redirect to show the preview
  */
 function post_preview() {
 
@@ -1034,7 +1034,17 @@ function post_preview() {
 			$id = $post->ID;
 	}
 
-	return $id;
+	if ( is_wp_error($id) )
+		wp_die( $id->get_error_message() );
+
+	if ( $_POST['post_status'] == 'draft'  ) {
+		$url = add_query_arg( 'preview', 'true', get_permalink($id) );
+	} else {
+		$nonce = wp_create_nonce('post_preview_' . $id);
+		$url = add_query_arg( array( 'preview' => 'true', 'preview_id' => $id, 'preview_nonce' => $nonce ), get_permalink($id) );
+	}
+
+	return $url;
 }
 
 /**

wp-admin/page.php

@@ -176,17 +176,7 @@ case 'delete':
 case 'preview':
 	check_admin_referer( 'autosave', 'autosavenonce' );
 
-	$id = post_preview();
-
-	if ( is_wp_error($id) )
-		wp_die( $id->get_error_message() );
-
-	if ( $_POST['post_status'] == 'draft'  ) {
-		$url = get_option('home') . '/?page_id=' . $id . '&preview=true';
-	} else {
-		$nonce = wp_create_nonce('post_preview_' . $id);
-		$url = get_option('home') . '/?wp_preview=' . $id . '&preview_nonce=' . $nonce;
-	}
+	$url = post_preview();
 
 	wp_redirect($url);
 	exit();

wp-admin/post.php

@@ -223,17 +223,7 @@ case 'delete':
 case 'preview':
 	check_admin_referer( 'autosave', 'autosavenonce' );
 
-	$id = post_preview();
-
-	if ( is_wp_error($id) )
-		wp_die( $id->get_error_message() );
-
-	if ( $_POST['post_status'] == 'draft'  ) {
-		$url = get_option('home') . '/?p=' . $id . '&preview=true';
-	} else {
-		$nonce = wp_create_nonce('post_preview_' . $id);
-		$url = get_option('home') . '/?wp_preview=' . $id . '&preview_nonce=' . $nonce;
-	}
+	$url = post_preview();
 
 	wp_redirect($url);
 	exit();

wp-includes/post.php

@@ -3552,24 +3552,33 @@ function wp_get_post_revisions( $post_id = 0, $args = null ) {
 	return $revisions;
 }
 
+function _set_preview($post) {
+
+	if ( ! is_object($post) )
+		return $post;
+
+	$preview = wp_get_post_autosave($post->ID);
+
+	if ( ! is_object($preview) )
+		return $post;
+
+	$preview = sanitize_post($preview);
+
+	$post->post_content = $preview->post_content;
+	$post->post_title = $preview->post_title;
+	$post->post_excerpt = $preview->post_excerpt;
+
+	return $post;
+}
+
 function _show_post_preview() {
 
-	if ( isset($_GET['wp_preview']) && isset($_GET['preview_nonce']) ) {
-		$post_ID = (int) $_GET['wp_preview'];
+	if ( isset($_GET['preview_id']) && isset($_GET['preview_nonce']) ) {
+		$id = (int) $_GET['preview_id'];
 
-		if ( false == wp_verify_nonce( $_GET['preview_nonce'], 'post_preview_' . $post_ID ) || ! current_user_can('edit_post', $post_ID) )
+		if ( false == wp_verify_nonce( $_GET['preview_nonce'], 'post_preview_' . $id ) )
 			wp_die( __('You do not have permission to preview drafts.') );
 
-		$q = array(
-			'name' => "{$post_ID}-autosave",
-			'post_parent' => $post_ID,
-			'post_type' => 'revision',
-			'post_status' => 'inherit'
-		);
-
-		add_action( 'parse_query', '_wp_get_post_autosave_hack' );
-		query_posts($q);
-		remove_action( 'parse_query', '_wp_get_post_autosave_hack' );
-
+		add_filter('the_preview', '_set_preview');
 	}
 }

wp-includes/query.php

@@ -2294,6 +2294,9 @@ class WP_Query {
 					}
 				}
 			}
+
+			if ( $this->is_preview && current_user_can( "edit_{$post_type}", $this->posts[0]->ID ) )
+				$this->posts[0] = apply_filters('the_preview', $this->posts[0]);
 		}
 
 		// Put sticky posts at the top of the posts array