--- /dev/null
+<?php
+
+namespace Drupal\Tests\views\Kernel;
+
+use Drupal\entity_test\Entity\EntityTest;
+use Drupal\views\Views;
+
+/**
+ * Tests the preprocessing functionality in views.theme.inc.
+ *
+ * @group views
+ */
+class ViewsPreprocessTest extends ViewsKernelTestBase {
+
+ /**
+ * {@inheritdoc}
+ */
+ public static $testViews = ['test_preprocess'];
+
+ /**
+ * {@inheritdoc}
+ */
+ public static $modules = ['entity_test', 'user', 'node'];
+
+ /**
+ * {@inheritdoc}
+ */
+ protected function setUp($import_test_views = TRUE) {
+ parent::setUp();
+
+ $this->installEntitySchema('entity_test');
+ }
+
+ /**
+ * Tests css classes on displays are cleaned correctly.
+ */
+ public function testCssClassCleaning() {
+ \Drupal::service('theme_handler')->install(['test_theme']);
+ $this->config('system.theme')->set('default', 'test_theme')->save();
+
+ $entity = EntityTest::create();
+ $entity->save();
+ /** @var \Drupal\Core\Render\RendererInterface $renderer */
+ $renderer = \Drupal::service('renderer');
+
+ $view = Views::getview('test_preprocess');
+ $build = $view->buildRenderable();
+ $renderer->renderRoot($build);
+ $this->assertContains('class="entity-test--default entity-test__default', (string) $build['#markup']);
+ $view->destroy();
+
+ $view->setDisplay('display_2');
+ $build = $view->buildRenderable();
+ $renderer->renderRoot($build);
+ $markup = (string) $build['#markup'];
+ $this->assertContains('css_class: entity-test--default and-another-class entity-test__default', $markup);
+ $this->assertContains('attributes: class="entity-test--default and-another-class entity-test__default', $markup);
+ }
+
+}