diff --git a/core/tests/Drupal/KernelTests/Core/Config/Storage/FileStorageTest.php b/core/tests/Drupal/KernelTests/Core/Config/Storage/FileStorageTest.php
index f4750a6c85..51ccf4bb1d 100644
--- a/core/tests/Drupal/KernelTests/Core/Config/Storage/FileStorageTest.php
+++ b/core/tests/Drupal/KernelTests/Core/Config/Storage/FileStorageTest.php
@@ -79,7 +79,8 @@ public function testUnsupportedDataTypeConfigException() {
     $name = 'core.extension';
     $path = $this->storage->getFilePath($name);
     $this->expectException(UnsupportedDataTypeConfigException::class);
-    $this->expectExceptionMessage("Invalid data type in config $name, found in file $path: Malformed inline YAML string: " . '"[bar}" at line 3 (near "foo : [bar}").');
+    $this->expectExceptionMessage("Invalid data type in config $name, found in file $path: Malformed inline YAML string: " . '"[bar}" at line 2 (near "foo : [bar}").');
+    unlink($path);
     file_put_contents($path, PHP_EOL . 'foo : [bar}', FILE_APPEND);
     $this->storage->read($name);
   }