diff --git a/core/modules/simpletest/simpletest.install b/core/modules/simpletest/simpletest.install
index 69ddb8a56ce280da1b88bdd2bbd814c97a0b5fc5..b36ed9a7f932ee96ea2636def735568ea14de235 100644
--- a/core/modules/simpletest/simpletest.install
+++ b/core/modules/simpletest/simpletest.install
@@ -7,6 +7,7 @@
 
 use Drupal\Core\Database\Database;
 use Drupal\Core\File\Exception\FileException;
+use Drupal\Core\Test\EnvironmentCleaner;
 use Drupal\Core\Test\TestDatabase;
 use Symfony\Component\Console\Output\NullOutput;