Prem Suthar
--- a/core/modules/locale/tests/src/Kernel/LocaleLegacyTest.php 0 → 100644
+++ b/core/modules/locale/tests/src/Kernel/LocaleLegacyTest.php 0 → 100644
+
+use Drupal\Core\DependencyInjection\ContainerBuilder;
+use Drupal\Core\Language\Language;
+use Drupal\KernelTests\KernelTestBase;
+use Drupal\language\Entity\ConfigurableLanguage;
+
+/**
+ * Tests legacy locale module code.
+ *
+ * @group locale
+ * @group legacy
+ */
+class LocaleLegacyTest extends KernelTestBase {
+
+  /**
+   * The modules to enable for this test.
--- a/core/modules/locale/tests/src/Kernel/LocaleLegacyTest.php 0 → 100644
+++ b/core/modules/locale/tests/src/Kernel/LocaleLegacyTest.php 0 → 100644
+    $language['name'] = 'Hungarian';
+    $container->setParameter('language.default_values', $language);
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  protected function setUp(): void {
+    parent::setUp();
+    ConfigurableLanguage::createFromLangcode('hu')->save();
+    $this->installSchema('locale', ['locales_source', 'locales_target', 'locales_location']);
+    $this->installConfig(['locale_test']);
+  }
+
+  /**
+   * Tests locale_system_set_config_langcodes().
--- a/core/modules/locale/locale.module
+++ b/core/modules/locale/locale.module

 /**
 * Updates default configuration when new modules or themes are installed.
+ *
+ * @deprecated in drupal:10.3.0 and is removed from drupal:11.0.0. Use
--- a/core/modules/user/tests/src/Kernel/UserMailNotifyTest.php
+++ b/core/modules/user/tests/src/Kernel/UserMailNotifyTest.php
    // Install configs.
    $this->installConfig(['language', 'locale', 'user']);

-    locale_system_set_config_langcodes();