Ticket #28155: 28155.2.diff

tests/phpunit/tests/db.php

@@ -458 +458 @@
                 $this->assertEquals( $expected2, $wpdb->last_query );
                 $wpdb->suppress_errors( $suppress );
         }
+
+        /**
+         * mysqli_ incorrect flush and further sync issues.
+         *
+         * @ticket 28155
+         */
+        function test_mysqli_flush_sync() {
+                global $wpdb;
+                if ( !$wpdb->use_mysqli )
+                        $this->markTestSkipped( 'mysqli not being used' );
+
+                $suppress = $wpdb->suppress_errors( true );
+
+                $wpdb->query( 'DROP PROCEDURE IF EXISTS `test_mysqli_flush_sync_procedure`' );
+                $wpdb->query( 'CREATE PROCEDURE `test_mysqli_flush_sync_procedure`() BEGIN
+                        SELECT ID FROM `' . $wpdb->posts . '` LIMIT 1;
+                END' );
+
+                if ( count( $wpdb->get_results( 'SHOW CREATE PROCEDURE `test_mysqli_flush_sync_procedure`' ) ) < 1 ) {
+                        $wpdb->suppress_errors( $suppress );
+                        $this->markTestSkipped( 'procedure could not be created (missing privileges?)' );
+                }
+
+                $this->factory->post->create();
+
+                $this->assertNotEmpty( $wpdb->get_results( 'CALL `test_mysqli_flush_sync_procedure`' ) );
+                $this->assertNotEmpty( $wpdb->get_results( "SELECT ID FROM `{$wpdb->posts}` LIMIT 1" ) );
+
+                $wpdb->query( 'DROP PROCEDURE IF EXISTS `test_mysqli_flush_sync_procedure`' );
+                $wpdb->suppress_errors( $suppress );
+        }
 }

src/wp-includes/wp-db.php

@@ -1324 +1324 @@
                 $this->rows_affected = $this->num_rows = 0;
                 $this->last_error  = '';
 
-                if ( is_resource( $this->result ) ) {
-                        if ( $this->use_mysqli ) {
-                                mysqli_free_result( $this->result );
-                        } else {
-                                mysql_free_result( $this->result );
-                        }
+                if ( $this->use_mysqli && $this->result instanceof mysqli_result ) {
+                        mysqli_free_result( $this->result );
+                        $this->result = null;
+                        if ( empty( $this->dbh ) || !( $this->dbh instanceof mysqli ) )
+                                return; // Sanity check before using the handle
+                        while ( $this->dbh->more_results() )
+                                $this->dbh->next_result();
+                } else if ( is_resource( $this->result ) ) {
+                        mysql_free_result( $this->result );
                 }
         }