diff --git a/tests/AssertTest.php b/tests/AssertTest.php
index 996e873d..4a23b061 100644
--- a/tests/AssertTest.php
+++ b/tests/AssertTest.php
@@ -133,6 +133,7 @@ public function getTests()
             array('isInstanceOf', array(new Exception(), 'stdClass'), false),
             array('isInstanceOf', array(123, 'stdClass'), false),
             array('isInstanceOf', array(array(), 'stdClass'), false),
+            array('isInstanceOf', array(null, 'stdClass'), false),
             array('notInstanceOf', array(new stdClass(), 'stdClass'), false),
             array('notInstanceOf', array(new Exception(), 'stdClass'), true),
             array('notInstanceOf', array(123, 'stdClass'), true),