diff --git a/tests/mock/event_dispatcher.php b/tests/mock/event_dispatcher.php
index 2f0f142905..53a1e2d87b 100644
--- a/tests/mock/event_dispatcher.php
+++ b/tests/mock/event_dispatcher.php
@@ -25,10 +25,11 @@ class phpbb_mock_event_dispatcher extends \phpbb\event\dispatcher
 	public function trigger_event($eventName, $data = array()): array
 	{
 		$data = (array) $data;
-		
+
+		// Throw an exception if we reach the core's exit_handler()
 		if ($eventName === 'core.exit_handler')
 		{
-			$data['exit_handler_override'] = true;
+			throw new \RuntimeException('Exit handler called');
 		}
 
 		return $data;