diff --git a/tests/src/Kernel/ModeManagerTest.php b/tests/src/Kernel/ModeManagerTest.php
index cefd863..38edd1a 100644
--- a/tests/src/Kernel/ModeManagerTest.php
+++ b/tests/src/Kernel/ModeManagerTest.php
@@ -87,7 +87,7 @@ final class ModeManagerTest extends KernelTestBase {
    * @return array
    *   Mock data set.
    */
-  public function getData() {
+  public static function getData() {
     return [
       ['text/x-sql', 'text/x-sql'],
       ['PHP', 'text/x-php'],