Ticket #24785: 24785.4.diff

tests/phpunit/tests/query.php

@@ -57 +57 @@
                         }
                 }
         }
+
+        /**
+         * @ticket 24785
+         *
+         */
+        function test_nested_loop_reset_postdata() {
+                $post_id = $this->factory->post->create();
+                $nested_post_id = $this->factory->post->create();
+
+                $first_query = new WP_Query( array( 'post__in' => array( $post_id ) ) );
+                while ( $first_query->have_posts() ) { $first_query->the_post();
+                        $second_query = new WP_Query( array( 'post__in' => array( $nested_post_id ) ) );
+                        while ( $second_query->have_posts() ) {
+                                $second_query->the_post();
+                                $this->assertEquals( get_the_ID(), $nested_post_id );
+                        }
+                        $first_query->reset_postdata();
+                        $this->assertEquals( get_the_ID(), $post_id );
+                }
+
+        }
 }
+ No newline at end of file

src/wp-includes/query.php

@@ -115 +115 @@
  */
 function wp_reset_postdata() {
         global $wp_query;
-        if ( !empty($wp_query->post) ) {
-                $GLOBALS['post'] = $wp_query->post;
-                setup_postdata($wp_query->post);
-        }
+        $wp_query->reset_postdata();
 }
 
 /*
@@ -3628 +3625 @@
                 global $wp_the_query;
                 return $wp_the_query === $this;
         }
+
+        /**
+         * After looping through a nested query, this function
+         * restores the $post global to the current post in this query
+         *
+         * @since 3.7.0
+         *
+         * @return bool
+         */
+        function reset_postdata() {
+                if ( ! empty( $this->post ) ) {
+                        $GLOBALS['post'] = $this->post;
+                        setup_postdata( $this->post );
+                }
+        }
 }
 
 /**