diff --git a/tests/unit/TestCase.php b/tests/unit/TestCase.php
index 3289be4..bd95465 100644
--- a/tests/unit/TestCase.php
+++ b/tests/unit/TestCase.php
@@ -37,6 +37,7 @@ abstract class TestCase extends \yii\test\TestCase
 	 * Populates Yii::$app with a new application
 	 * The application will be destroyed on tearDown() automatically.
 	 * @param array $config The application configuration, if needed
+	 * @param string $appClass name of the application class to create
 	 */
 	protected function mockApplication($config = array(), $appClass = '\yii\console\Application')
 	{