Ticket #4575: 4575.10.diff

src/wp-includes/feed-atom-comments.php

@@ -42 +42 @@
         <subtitle type="text"><?php bloginfo_rss('description'); ?></subtitle>
 
         <updated><?php
-                $date = get_lastcommentmodified( 'GMT' );
+                $date = get_last_build_date();
                 echo $date ? mysql2date( 'Y-m-d\TH:i:s\Z', $date, false ) : date( 'Y-m-d\TH:i:s\Z' );
         ?></updated>
 

src/wp-includes/feed-atom.php

@@ -31 +31 @@
         <subtitle type="text"><?php bloginfo_rss("description") ?></subtitle>
 
         <updated><?php
-                $date = get_lastpostmodified( 'GMT' );
+                $date = get_last_build_date();
                 echo $date ? mysql2date( 'Y-m-d\TH:i:s\Z', $date, false ) : date( 'Y-m-d\TH:i:s\Z' );
         ?></updated>
 

src/wp-includes/feed-rss2-comments.php

@@ -48 +48 @@
         <link><?php (is_single()) ? the_permalink_rss() : bloginfo_rss("url") ?></link>
         <description><?php bloginfo_rss("description") ?></description>
         <lastBuildDate><?php
-                $date = get_lastcommentmodified( 'GMT' );
+                $date = get_last_build_date();
                 echo $date ? mysql2date( 'r', $date, false ) : date( 'r' );
         ?></lastBuildDate>
         <sy:updatePeriod><?php

src/wp-includes/feed-rss2.php

@@ -43 +43 @@
         <link><?php bloginfo_rss('url') ?></link>
         <description><?php bloginfo_rss("description") ?></description>
         <lastBuildDate><?php
-                $date = get_lastpostmodified( 'GMT' );
+                $date = get_last_build_date();
                 echo $date ? mysql2date( 'r', $date, false ) : date( 'r' );
         ?></lastBuildDate>
         <language><?php bloginfo_rss( 'language' ); ?></language>

src/wp-includes/feed.php

@@ -89 +89 @@
 }
 
 /**
+ * Get the timestamp of the most recently modified post from WP_Query
+ *
+ * If viewing a comment feed, the date of the most recently modified
+ * comment will be returned.
+ *
+ * @since 4.8.1
+ *
+ * @return string Date ('Y-m-d H:i:s' for use with mysql2date() )
+ */
+function get_last_build_date() {
+        global $wp_query;
+
+        if ( $wp_query->have_posts() ) {
+                // Determine max post time
+                $post_times = wp_list_pluck( $wp_query->posts, 'post_modified_gmt' );
+                $max_post_time = max( $post_times );
+
+                // If this is a comment feed, check those objects too
+                if ( $wp_query->is_comment_feed() && $wp_query->have_comments() ) {
+                        // Determine the max comment time
+                        $comment_times = wp_list_pluck( $wp_query->comments, 'comment_date_gmt' );
+                        $max_comment_time = max( $comment_times );
+
+                        // Return the most recent timestamp between posts and comments
+                        return max( $max_post_time, $max_comment_time );
+                }
+                // Return the most recent post timestamp if there are no comments to consider
+                return $max_post_time;
+        }
+
+        // Fallback to last time any post was modified or published
+        return get_lastpostmodified( 'GMT' );
+ }
+
+/**
  * Retrieve the blog title for the feed title.
  *
  * @since 2.2.0

tests/phpunit/tests/feed/rss2.php

@@ -32 +32 @@
                 ) );
 
                 // Set a predictable time for testing date archives.
-                self::$post_date = '2003-05-27 10:07:53';
+                self::$post_date = strtotime( '2003-05-27 10:07:53' );
 
                 $count = get_option( 'posts_per_rss' ) + 1;
+                $i = 0;
 
                 // Create a few posts
-                self::$posts = $factory->post->create_many( $count, array(
-                        'post_author'  => self::$user_id,
-                        'post_date'    => self::$post_date,
-                        'post_content' => 'Lorem ipsum dolor sit amet, consectetur adipiscing elit. Donec velit massa, ultrices eu est suscipit, mattis posuere est. Donec vitae purus lacus. Cras vitae odio odio.',
-                        'post_excerpt' => 'Lorem ipsum dolor sit amet, consectetur adipiscing elit.',
-                ) );
+                self::$posts = array();
+                while ( $count-- ) {
+                        self::$posts[] = $factory->post->create( array(
+                                'post_author'  => self::$user_id,
+                                'post_date'    => gmdate( 'Y-m-d H:i:s', self::$post_date + ( 5 * ++$i ) ), // separate post dates 5 seconds apart.
+                                'post_content' => 'Lorem ipsum dolor sit amet, consectetur adipiscing elit. Donec velit massa, ultrices eu est suscipit, mattis posuere est. Donec vitae purus lacus. Cras vitae odio odio.',
+                                'post_excerpt' => 'Lorem ipsum dolor sit amet, consectetur adipiscing elit.',
+                        ) );
+                }
 
                 // Assign a category to those posts
                 foreach ( self::$posts as $post ) {
@@ -83 +87 @@
         }
 
         /**
+         * Test <rss> element has correct last build date.
+         */
+        function test_get_last_build_date() {
+                $this->go_to( '/?feed=rss2' );
+                $feed = $this->do_rss2();
+                $xml = xml_to_array( $feed );
+
+                // Get the <rss> child element of <xml>.
+                $rss = xml_find( $xml, 'rss' );
+                $last_build_date = $rss[0]['child'][0]['child'][4]['content'];
+                $this->assertEquals( strtotime( get_last_build_date() ), strtotime( $last_build_date ) );
+        }
+
+        /**
          * Test the <rss> element to make sure its present and populated
          * with the expected child elements and attributes.
          */