--- /dev/null
+<?php
+
+namespace Drupal\Tests\language\Kernel;
+
+use Drupal\entity_test\Entity\EntityTest;
+use Drupal\KernelTests\KernelTestBase;
+
+/**
+ * Tests the language select widget.
+ *
+ * @group language
+ */
+class LanguageSelectWidgetTest extends KernelTestBase {
+
+ /**
+ * {@inheritdoc}
+ */
+ protected static $modules = [
+ 'entity_test',
+ 'language',
+ 'user',
+ 'system',
+ ];
+
+ /**
+ * The entity form display.
+ *
+ * @var \Drupal\Core\Entity\Entity\EntityFormDisplay
+ */
+ protected $entityFormDisplay;
+
+ /**
+ * {@inheritdoc}
+ */
+ protected function setUp() {
+ parent::setUp();
+
+ $this->installEntitySchema('entity_test');
+ $this->installEntitySchema('user');
+
+ $storage = $this->container->get('entity_type.manager')->getStorage('entity_form_display');
+ $this->entityFormDisplay = $storage->create([
+ 'targetEntityType' => 'entity_test',
+ 'bundle' => 'entity_test',
+ 'mode' => 'default',
+ 'status' => TRUE,
+ ]);
+ }
+
+ /**
+ * Tests the widget with the locked languages.
+ */
+ public function testWithIncludedLockedLanguage() {
+ $this->entityFormDisplay->setComponent('langcode', [
+ 'type' => 'language_select',
+ ])->save();
+ $entity = EntityTest::create(['name' => $this->randomString()]);
+ $form = $this->container->get('entity.form_builder')->getForm($entity);
+ $options = array_keys($form['langcode']['widget'][0]['value']['#options']);
+ $this->assertSame(['en', 'und', 'zxx'], $options);
+ }
+
+ /**
+ * Test the widget without the locked languages.
+ */
+ public function testWithoutIncludedLockedLanguage() {
+ $this->entityFormDisplay->setComponent('langcode', [
+ 'type' => 'language_select',
+ 'settings' => ['include_locked' => FALSE],
+ ])->save();
+ $entity = EntityTest::create(['name' => $this->randomString()]);
+ $form = $this->container->get('entity.form_builder')->getForm($entity);
+ $options = array_keys($form['langcode']['widget'][0]['value']['#options']);
+ $this->assertSame(['en'], $options);
+ }
+
+}