Ticket #35082: adjacent-post-in-term.diff

src/wp-includes/link-template.php

@@ -1583 +1583 @@
                 }
 
                 if ( $in_same_term ) {
+
                         $join .= " INNER JOIN $wpdb->term_relationships AS tr ON p.ID = tr.object_id INNER JOIN $wpdb->term_taxonomy tt ON tr.term_taxonomy_id = tt.term_taxonomy_id";
                         $where .= $wpdb->prepare( "AND tt.taxonomy = %s", $taxonomy );
 
                         if ( ! is_object_in_taxonomy( $post->post_type, $taxonomy ) )
                                 return '';
-                        $term_array = wp_get_object_terms( $post->ID, $taxonomy, array( 'fields' => 'ids' ) );
+
+                        // Get all fields rather than just IDs, so we have access to parent ID
+                        $term_objects = wp_get_object_terms( $post->ID, $taxonomy, array( 'fields' => 'all' ) );
+
+                        // Seperated WP error check from empty check as needs to run earlier
+                        if( is_wp_error( $term_objects ) )
+                                return '';
+
+                        // Loop over our terms and store the IDs
+                        $term_ids = array();
+                        foreach( $term_objects as $term )
+                                $term_ids[] = (int) $term->term_id;
+
+                        // Loop over the terms and if a terms parent exists, remove the parent
+                        foreach( $term_objects as $term ) {
+                                if( $term_parent = in_array($term->parent, $term_ids) )
+                                        unset($term_ids[$term_parent]);
+                        }
 
                         // Remove any exclusions from the term array to include.
-                        $term_array = array_diff( $term_array, (array) $excluded_terms );
-                        $term_array = array_map( 'intval', $term_array );
+                        $term_ids = array_diff( $term_ids, (array) $excluded_terms );
 
-                        if ( ! $term_array || is_wp_error( $term_array ) )
+                        // If the term objects array is now empty
+                        if ( ! $term_objects )
                                 return '';
 
-                        $where .= " AND tt.term_id IN (" . implode( ',', $term_array ) . ")";
+                        $where .= " AND tt.term_id IN (" . implode( ',', $term_ids ) . ")";
                 }
 
                 if ( ! empty( $excluded_terms ) ) {

tests/phpunit/tests/link.php

@@ -305 +305 @@
         }
 
         /**
+         * @ticket 35082
+         */
+        public function test_get_adjacent_post_in_same_term() {
+                // Need some sample posts to test adjacency
+                $post_one = self::factory()->post->create_and_get( array(
+                        'post_title' => 'First',
+                        'post_date' => '2012-01-01 12:00:00'
+                ) );
+
+                $post_two = self::factory()->post->create_and_get( array(
+                        'post_title' => 'Second',
+                        'post_date' => '2012-02-01 12:00:00'
+                ) );
+
+                $post_three = self::factory()->post->create_and_get( array(
+                        'post_title' => 'Third',
+                        'post_date' => '2012-03-01 12:00:00'
+                ) );
+
+                $post_four = self::factory()->post->create_and_get( array(
+                        'post_title' => 'Fourth',
+                        'post_date' => '2012-04-01 12:00:00'
+                ) );
+
+                // Create terms
+                $term_one = wp_insert_term('parent', 'category');
+                $term_two = wp_insert_term('child', 'category', array('parent' => $term_one['term_id']));
+
+                // Assign some terms
+                wp_set_object_terms( $post_one->ID, array('parent', 'child'), 'category', false );
+                wp_set_object_terms( $post_two->ID, 'parent', 'category', false );
+
+                wp_set_object_terms( $post_three->ID, array('parent', 'child'), 'category', false );
+                wp_set_object_terms( $post_four->ID, array('child'), 'category', false );
+
+                // Post one should have no prior posts and next post should be three
+                $this->go_to( get_permalink( $post_one->ID ) );
+                $this->assertEquals( '', get_adjacent_post( true, '', true ) );
+                $this->assertEquals( $post_three, get_adjacent_post( true, '', false ) );
+
+                // Post three previous should be one and next should be four
+                $this->go_to( get_permalink( $post_three->ID ) );
+                $this->assertEquals( $post_one, get_adjacent_post( true, '', true ) );
+                $this->assertEquals( $post_four, get_adjacent_post( true, '', false ) );
+
+                // Post two should have next post of three and previous of one
+                $this->go_to( get_permalink( $post_two->ID ) );
+                $this->assertEquals( $post_one, get_adjacent_post( true, '', true ) );
+                $this->assertEquals( $post_three, get_adjacent_post( true, '', false ) );
+
+                // Post four should have next post of one and previous of three
+                $this->go_to( get_permalink( $post_four->ID ) );
+                $this->assertEquals( $post_three, get_adjacent_post( true, '', true ) );
+                $this->assertEquals( '', get_adjacent_post( true, '', false ) );
+        }
+
+        /**
          * @ticket 30910
          */
         public function test_get_permalink_should_not_reveal_post_name_for_post_with_post_status_future() {