diff --git a/tests/ReturnTypeProvider/DirnameTest.php b/tests/ReturnTypeProvider/DirnameTest.php
index 5ba691a223d..e1b4d01d382 100644
--- a/tests/ReturnTypeProvider/DirnameTest.php
+++ b/tests/ReturnTypeProvider/DirnameTest.php
@@ -5,6 +5,8 @@
 use Psalm\Tests\TestCase;
 use Psalm\Tests\Traits\ValidCodeAnalysisTestTrait;
 
+use function addslashes;
+
 use const DIRECTORY_SEPARATOR;
 
 class DirnameTest extends TestCase