@@ -456,7 +456,7 @@ public function _display($output = NULL)
 
 		$elapsed = $BM->elapsed_time('total_execution_time_start', 'total_execution_time_end');
 
-		if ($this->parse_exec_vars === TRUE)
+		if ($this->parse_exec_vars === TRUE && !empty($output))
 		{
 			$memory	= round(memory_get_usage() / 1024 / 1024, 2).'MB';
 			$output = str_replace(array('{elapsed_time}', '{memory_usage}'), array($elapsed, $memory), $output);