Ticket #7392: 7392.4.patch

wp-admin/includes/post.php

@@ -1296 +1296 @@
  * @subpackage Post_Revisions
  * @since 2.6.0
  *
+ * @uses get_post()
  * @uses _wp_translate_postdata()
+ * @uses is_wp_error()
+ * @uses get_current_user_id()
+ * @uses wp_get_post_autosave()
  * @uses _wp_post_revision_fields()
+ * @uses apply_filters()
+ * @uses normalize_whitespace()
+ * @uses wp_update_post()
+ * @uses wp_unslash()
+ * @uses _wp_put_post_revision()
  *
- * @return unknown
+ * @return mixed
  */
 function wp_create_post_autosave( $post_id ) {
+        if ( ! $post = get_post( $post_id ) )
+                return;
+
         $translated = _wp_translate_postdata( true );
         if ( is_wp_error( $translated ) )
                 return $translated;
@@ -1314 +1326 @@
                 $new_autosave['ID'] = $old_autosave->ID;
                 $new_autosave['post_author'] = $post_author;
 
+                // Check if post content has changed before autosaving
+                if ( is_array( $new_autosave ) && apply_filters( 'wp_save_post_revision_check_for_changes', true, $post, $new_autosave ) ) {
+                        $post_has_changed = false;
+
+                        foreach ( array_keys( _wp_post_revision_fields() ) as $field ) {
+                                if ( normalize_whitespace( $new_autosave[ $field ] ) != normalize_whitespace( $post->{$field} ) ) {
+                                        $post_has_changed = true;
+                                        break;
+                                }
+                        }
+
+                        // Don't save anything new if post is unchanged
+                        if ( ! $post_has_changed )
+                                return;
+                }
+
                 return wp_update_post( $new_autosave );
         }