diff --git a/tests/bootstrap.php b/tests/bootstrap.php
index caf694a..1ef6735 100644
--- a/tests/bootstrap.php
+++ b/tests/bootstrap.php
@@ -12,4 +12,4 @@ require_once(__DIR__ . '/../vendor/autoload.php');
 require_once(__DIR__ . '/../vendor/yiisoft/yii2/Yii.php');
 
 Yii::setAlias('@yiiunit/extensions/swiftmailer', __DIR__);
-Yii::setAlias('@yii/swiftmailer', dirname(__DIR__));
\ No newline at end of file
+Yii::setAlias('@yii/swiftmailer', dirname(__DIR__) . '/src');
\ No newline at end of file