diff --git a/tests/Persistence/Mapping/DriverChainTest.php b/tests/Persistence/Mapping/DriverChainTest.php
index 11cf5973..c752b1fb 100644
--- a/tests/Persistence/Mapping/DriverChainTest.php
+++ b/tests/Persistence/Mapping/DriverChainTest.php
@@ -63,7 +63,7 @@ public function testGatherAllClassNames(): void
         $driver1 = $this->createMock(MappingDriver::class);
         $driver1->expects(self::once())
                 ->method('getAllClassNames')
-                ->will(self::returnValue(['Doctrine\Tests\Models\Company\Foo','Doctrine\Tests\Models\Company2\Foo']));
+                ->will(self::returnValue(['Doctrine\Tests\Models\Company\Foo', 'Doctrine\Tests\Models\Company2\Foo']));
 
         $driver2 = $this->createMock(MappingDriver::class);
         $driver2->expects(self::once())