diff --git a/_tests/ParallelOutput.php b/_tests/ParallelOutput.php
index 719af164..7125f5d5 100644
--- a/_tests/ParallelOutput.php
+++ b/_tests/ParallelOutput.php
@@ -8,6 +8,7 @@ class ParallelOutput {
 	private $headers;
 	private $processStatus;
 	private $startTimes;
+	private $nonJsonOutput;
 
 	public function __construct() {
 		$this->rawOutput     = '';