Ticket #40293: 40293.2.diff

src/wp-includes/comment-template.php

@@ -1379 +1379 @@
 
                         $top_level_count = $top_level_query->query( $top_level_args );
 
-                        $comment_args['offset'] = ( ceil( $top_level_count / $per_page ) - 1 ) * $per_page;
+                        if ( $top_level_count && $per_page ) {
+                                $comment_args['offset'] = ( ceil( $top_level_count / $per_page ) - 1 ) * $per_page;
+                        } else {
+                                $comment_args['offset'] = 0;
+                        }
                 }
         }
 

tests/phpunit/tests/comment/commentsTemplate.php

@@ -128 +128 @@
         }
 
         /**
+         * @ticket 40293
+         */
+        public function test_should_handle_zero_comments_per_page_with_comments_broken_into_pages_and_last_page_displayed_by_default() {
+                $now = time();
+                $p = self::factory()->post->create();
+
+                $comment_1 = self::factory()->comment->create( array(
+                        'comment_post_ID' => $p,
+                        'comment_content' => '1',
+                        'comment_date_gmt' => date( 'Y-m-d H:i:s', $now - 100 ),
+                ) );
+                $comment_2 = self::factory()->comment->create( array(
+                        'comment_post_ID' => $p,
+                        'comment_content' => '2',
+                        'comment_date_gmt' => date( 'Y-m-d H:i:s', $now ),
+                ) );
+
+                update_option( 'comment_order', 'desc' );
+                update_option( 'default_comments_page', 'newest' ); // last (newest) page displayed by default
+                update_option( 'comments_per_page', '0' );          // top level comments per page
+                update_option( 'page_comments', '1' );              // break comments into pages
+
+                $this->go_to( get_permalink( $p ) );
+                $found = get_echo( 'comments_template' );    
+
+                preg_match_all( '/id="comment-([0-9]+)"/', $found, $matches );
+
+                $found_cids = array_map( 'intval', $matches[1] );
+                $this->assertSame( array( $comment_2, $comment_1 ), $found_cids );
+        }
+
+        /**
          * @ticket 8071
          */
         public function test_should_respect_comment_order_asc_when_default_comments_page_is_newest_on_subsequent_pages() {