Drupal 8.0.0 beta 12. More info: https://www.drupal.org/node/2514176

core/modules/system/tests/modules/accept_header_routing_test/accept_header_routing_test.info.yml

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+name: Accept header based routing test
+core: 8.x
+type: module

core/modules/system/tests/modules/accept_header_routing_test/accept_header_routing_test.services.yml

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+services:
+  accept_header_matcher:
+    class: Drupal\accept_header_routing_test\Routing\AcceptHeaderMatcher
+    tags:
+      - { name: route_filter }

core/modules/system/tests/modules/accept_header_routing_test/src/AcceptHeaderMiddleware.php

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+<?php
+
+/**
+ * @file
+ * Contains \Drupal\accept_header_routing_test\AcceptHeaderMiddleware.
+ */
+
+namespace Drupal\accept_header_routing_test;
+
+use Symfony\Component\HttpFoundation\Request;
+use Symfony\Component\HttpKernel\HttpKernelInterface;
+
+/**
+ * Example implementation of accept header based content negotation.
+ */
+class AcceptHeaderMiddleware implements HttpKernelInterface {
+
+  /**
+   * Constructs a new AcceptHeaderMiddleware instance.
+   *
+   * @param \Symfony\Component\HttpKernel\HttpKernelInterface $app
+   *   The app.
+   */
+  public function __construct(HttpKernelInterface $app) {
+    $this->app = $app;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function handle(Request $request, $type = self::MASTER_REQUEST, $catch = TRUE) {
+    $mapping = [
+      'application/json' => 'json',
+      'application/hal+json' => 'hal_json',
+      'application/xml' => 'xml',
+      'text/html' => 'html',
+    ];
+
+    $accept = $request->headers->get('Accept') ?: ['text/html'];
+    if (isset($mapping[$accept[0]])) {
+      $request->setRequestFormat($mapping[$accept[0]]);
+    }
+
+    return $this->app->handle($request, $type, $catch);
+  }
+
+}

core/modules/system/tests/modules/accept_header_routing_test/src/AcceptHeaderRoutingTestServiceProvider.php

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+<?php
+
+/**
+ * @file
+ * Contains \Drupal\accept_header_routing_test\AcceptHeaderRoutingTestServiceProvider.
+ */
+
+namespace Drupal\accept_header_routing_test;
+
+use Drupal\Core\DependencyInjection\ContainerBuilder;
+use Drupal\Core\DependencyInjection\ServiceModifierInterface;
+
+/**
+ * Service provider for the accept_header_routing_test module.
+ */
+class AcceptHeaderRoutingTestServiceProvider implements ServiceModifierInterface {
+
+  /**
+   * {@inheritdoc}
+   */
+  public function alter(ContainerBuilder $container) {
+    // Remove the basic content negotation middleware and replace it with a
+    // basic header based one.
+    $container->register('http_middleware.negotiation', 'Drupal\accept_header_routing_test\AcceptHeaderMiddleware')
+      ->addTag('http_middleware', ['priority' => 400]);
+  }
+
+}

core/modules/system/tests/modules/accept_header_routing_test/src/Routing/AcceptHeaderMatcher.php

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+<?php
+
+/**
+ * @file
+ * Contains \Drupal\accept_header_routing_test\Routing\AcceptHeaderMatcher.
+ */
+
+namespace Drupal\accept_header_routing_test\Routing;
+
+use Drupal\Component\Utility\SafeMarkup;
+use Drupal\Core\Routing\RouteFilterInterface;
+use Symfony\Component\HttpFoundation\Request;
+use Symfony\Component\HttpKernel\Exception\NotAcceptableHttpException;
+use Symfony\Component\Routing\Route;
+use Symfony\Component\Routing\RouteCollection;
+
+/**
+ * Filters routes based on the media type specified in the HTTP Accept headers.
+ */
+class AcceptHeaderMatcher implements RouteFilterInterface {
+
+  /**
+   * {@inheritdoc}
+   */
+  public function filter(RouteCollection $collection, Request $request) {
+    // Generates a list of Symfony formats matching the acceptable MIME types.
+    // @todo replace by proper content negotiation library.
+    $acceptable_mime_types = $request->getAcceptableContentTypes();
+    $acceptable_formats = array_filter(array_map(array($request, 'getFormat'), $acceptable_mime_types));
+    $primary_format = $request->getRequestFormat();
+
+    foreach ($collection as $name => $route) {
+      // _format could be a |-delimited list of supported formats.
+      $supported_formats = array_filter(explode('|', $route->getRequirement('_format')));
+
+      if (empty($supported_formats)) {
+        // No format restriction on the route, so it always matches. Move it to
+        // the end of the collection by re-adding it.
+        $collection->add($name, $route);
+      }
+      elseif (in_array($primary_format, $supported_formats)) {
+        // Perfect match, which will get a higher priority by leaving the route
+        // on top of the list.
+      }
+      // The route partially matches if it doesn't care about format, if it
+      // explicitly allows any format, or if one of its allowed formats is
+      // in the request's list of acceptable formats.
+      elseif (in_array('*/*', $acceptable_mime_types) || array_intersect($acceptable_formats, $supported_formats)) {
+        // Move it to the end of the list.
+        $collection->add($name, $route);
+      }
+      else {
+        // Remove the route if it does not match at all.
+        $collection->remove($name);
+      }
+    }
+
+    if (count($collection)) {
+      return $collection;
+    }
+
+    // We do not throw a
+    // \Symfony\Component\Routing\Exception\ResourceNotFoundException here
+    // because we don't want to return a 404 status code, but rather a 406.
+    throw new NotAcceptableHttpException(SafeMarkup::format('No route found for the specified formats @formats.', array('@formats' => implode(' ', $acceptable_mime_types))));
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function applies(Route $route) {
+    return TRUE;
+  }
+
+}

core/modules/system/tests/modules/accept_header_routing_test/tests/Unit/AcceptHeaderMatcherTest.php

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+<?php
+
+/**
+ * @file
+ * Contains \Drupal\Tests\accept_header_routing_teste\Unit\Routing\AcceptHeaderMatcherTest.
+ */
+
+namespace Drupal\Tests\accept_header_routing_teste\Unit\Routing;
+
+use Drupal\accept_header_routing_test\Routing\AcceptHeaderMatcher;
+use Drupal\Tests\Core\Routing\RoutingFixtures;
+use Drupal\Tests\UnitTestCase;
+use Symfony\Component\HttpFoundation\Request;
+
+/**
+ * Confirm that the mime types partial matcher is functioning properly.
+ *
+ * @group Routing
+ */
+class AcceptHeaderMatcherTest extends UnitTestCase {
+
+  /**
+   * A collection of shared fixture data for tests.
+   *
+   * @var \Drupal\Tests\Core\Routing\RoutingFixtures
+   */
+  protected $fixtures;
+
+  /**
+   * The matcher object that is going to be tested.
+   *
+   * @var \Drupal\accept_header_routing_test\Routing\AcceptHeaderMatcher
+   */
+  protected $matcher;
+
+  /**
+   * {@inheritdoc}
+   */
+  protected function setUp() {
+    parent::setUp();
+
+    $this->fixtures = new RoutingFixtures();
+    $this->matcher = new AcceptHeaderMatcher();
+  }
+
+  /**
+   * Provides data for the Accept header filtering test.
+   *
+   * @see Drupal\Tests\Core\Routing\AcceptHeaderMatcherTest::testAcceptFiltering()
+   */
+  public function acceptFilterProvider() {
+    return [
+      // Check that JSON routes get filtered and prioritized correctly.
+      ['application/json, text/xml;q=0.9', 'json', 'route_c', 'route_e'],
+      // Tests a JSON request with alternative JSON MIME type Accept header.
+      ['application/x-json, text/xml;q=0.9', 'json', 'route_c', 'route_e'],
+      // Tests a standard HTML request.
+      ['text/html, text/xml;q=0.9', 'html', 'route_e', 'route_c'],
+    ];
+  }
+
+  /**
+   * Tests that requests using Accept headers get filtered correctly.
+   *
+   * @param string $accept_header
+   *   The HTTP Accept header value of the request.
+   * @param string $format
+   *   The request format.
+   * @param string $included_route
+   *   The route name that should survive the filter and be ranked first.
+   * @param string $excluded_route
+   *   The route name that should be filtered out during matching.
+   *
+   * @dataProvider acceptFilterProvider
+   */
+  public function testAcceptFiltering($accept_header, $format, $included_route, $excluded_route) {
+    $collection = $this->fixtures->sampleRouteCollection();
+
+    $request = Request::create('path/two', 'GET');
+    $request->headers->set('Accept', $accept_header);
+    $request->setRequestFormat($format);
+    $routes = $this->matcher->filter($collection, $request);
+    $this->assertEquals(count($routes), 4, 'The correct number of routes was found.');
+    $this->assertNotNull($routes->get($included_route), "Route $included_route was found when matching $accept_header.");
+    $this->assertNull($routes->get($excluded_route), "Route $excluded_route was not found when matching $accept_header.");
+    foreach ($routes as $name => $route) {
+      $this->assertEquals($name, $included_route, "Route $included_route is the first one in the collection when matching $accept_header.");
+      break;
+    }
+  }
+
+  /**
+   * Confirms that the AcceptHeaderMatcher throws an exception for no-route.
+   *
+   * @expectedException \Symfony\Component\HttpKernel\Exception\NotAcceptableHttpException
+   * @expectedExceptionMessage No route found for the specified formats application/json text/xml.
+   */
+  public function testNoRouteFound() {
+    // Remove the sample routes that would match any method.
+    $routes = $this->fixtures->sampleRouteCollection();
+    $routes->remove('route_a');
+    $routes->remove('route_b');
+    $routes->remove('route_c');
+    $routes->remove('route_d');
+
+    $request = Request::create('path/two', 'GET');
+    $request->headers->set('Accept', 'application/json, text/xml;q=0.9');
+    $request->setRequestFormat('json');
+    $this->matcher->filter($routes, $request);
+    $this->matcher->filter($routes, $request);
+    $this->fail('No exception was thrown.');
+  }
+
+}

core/modules/system/tests/modules/action_test/action_test.info.yml

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+name: 'Action test'
+type: module
+description: 'Support module for action testing.'
+package: Testing
+version: VERSION
+core: 8.x

core/modules/system/tests/modules/action_test/src/Plugin/Action/NoType.php

@@ -0,0 +1,38 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\action_test\Plugin\Action\NoType.
+ */
+
+namespace Drupal\action_test\Plugin\Action;
+
+use Drupal\Core\Access\AccessResult;
+use Drupal\Core\Action\ActionBase;
+use Drupal\Core\Session\AccountInterface;
+
+/**
+ * Provides an operation with no type specified.
+ *
+ * @Action(
+ *   id = "action_test_no_type",
+ *   label = @Translation("An operation with no type specified")
+ * )
+ */
+class NoType extends ActionBase {
+
+  /**
+   * {@inheritdoc}
+   */
+  public function execute($entity = NULL) {
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function access($object, AccountInterface $account = NULL, $return_as_object = FALSE) {
+    $result = AccessResult::allowed();
+    return $return_as_object ? $result : $result->isAllowed();
+  }
+
+}

core/modules/system/tests/modules/action_test/src/Plugin/Action/SaveEntity.php

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+<?php
+
+/**
+ * @file
+ * Contains \Drupal\action_test\Plugin\Action\SaveEntity.
+ */
+
+namespace Drupal\action_test\Plugin\Action;
+
+use Drupal\Core\Action\ActionBase;
+use Drupal\Core\Session\AccountInterface;
+
+/**
+ * Provides an operation to save user entities.
+ *
+ * @Action(
+ *   id = "action_test_save_entity",
+ *   label = @Translation("Saves entities"),
+ *   type = "user"
+ * )
+ */
+class SaveEntity extends ActionBase {
+
+  /**
+   * {@inheritdoc}
+   */
+  public function execute($entity = NULL) {
+    $entity->save();
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function access($object, AccountInterface $account = NULL, $return_as_object = FALSE) {
+    /** @var \Drupal\Core\Entity\EntityInterface $object */
+    return $object->access('update', $account, $return_as_object);
+  }
+
+}

core/modules/system/tests/modules/ajax_forms_test/ajax_forms_test.info.yml

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+name: 'AJAX form test mock module'
+type: module
+description: 'Test for AJAX form calls.'
+core: 8.x
+package: Testing
+version: VERSION

core/modules/system/tests/modules/ajax_forms_test/ajax_forms_test.module

@@ -0,0 +1,198 @@
+<?php
+
+/**
+ * @file
+ * Simpletest mock module for Ajax forms testing.
+ */
+
+use Drupal\Core\Ajax;
+use Drupal\Core\Ajax\AjaxResponse;
+use Drupal\Core\Form\FormStateInterface;
+
+/**
+ * Ajax form callback: Selects 'after'.
+ */
+function ajax_forms_test_advanced_commands_after_callback($form, FormStateInterface $form_state) {
+  $selector = '#after_div';
+
+  $response = new AjaxResponse();
+  $response->addCommand(new Ajax\AfterCommand($selector, "This will be placed after"));
+  return $response;
+}
+
+/**
+ * Ajax form callback: Selects 'alert'.
+ */
+function ajax_forms_test_advanced_commands_alert_callback($form, FormStateInterface $form_state) {
+  $response = new AjaxResponse();
+  $response->addCommand(new Ajax\AlertCommand('Alert'));
+  return $response;
+}
+
+/**
+ * Ajax form callback: Selects 'append'.
+ */
+function ajax_forms_test_advanced_commands_append_callback($form, FormStateInterface $form_state) {
+  $selector = '#append_div';
+  $response = new AjaxResponse();
+  $response->addCommand(new Ajax\AppendCommand($selector, "Appended text"));
+  return $response;
+}
+
+/**
+ * Ajax form callback: Selects 'before'.
+ */
+function ajax_forms_test_advanced_commands_before_callback($form, FormStateInterface $form_state) {
+  $selector = '#before_div';
+  $response = new AjaxResponse();
+  $response->addCommand(new Ajax\BeforeCommand($selector, "Before text"));
+  return $response;
+}
+
+/**
+ * Ajax form callback: Selects 'changed'.
+ */
+function ajax_forms_test_advanced_commands_changed_callback($form, FormStateInterface $form_state) {
+  $response = new AjaxResponse();
+  $response->addCommand(new Ajax\ChangedCommand('#changed_div'));
+  return $response;
+}
+
+/**
+ * Ajax form callback: Selects 'changed' with asterisk marking inner div.
+ */
+function ajax_forms_test_advanced_commands_changed_asterisk_callback($form, FormStateInterface $form_state) {
+  $response = new AjaxResponse();
+  $response->addCommand(new Ajax\ChangedCommand('#changed_div', '#changed_div_mark_this'));
+  return $response;
+}
+
+/**
+ * Ajax form callback: Selects 'css'.
+ */
+function ajax_forms_test_advanced_commands_css_callback($form, FormStateInterface $form_state) {
+  $selector = '#css_div';
+  $color = 'blue';
+
+  $response = new AjaxResponse();
+  $response->addCommand(new Ajax\CssCommand($selector, array('background-color' => $color)));
+  return $response;
+}
+
+/**
+ * Ajax form callback: Selects 'data'.
+ */
+function ajax_forms_test_advanced_commands_data_callback($form, FormStateInterface $form_state) {
+  $selector = '#data_div';
+  $response = new AjaxResponse();
+  $response->addCommand(new Ajax\DataCommand($selector, 'testkey', 'testvalue'));
+  return $response;
+}
+
+/**
+ * Ajax form callback: Selects 'invoke'.
+ */
+function ajax_forms_test_advanced_commands_invoke_callback($form, FormStateInterface $form_state) {
+  $response = new AjaxResponse();
+  $response->addCommand(new Ajax\InvokeCommand('#invoke_div', 'addClass', array('error')));
+  return $response;
+}
+
+/**
+ * Ajax form callback: Selects 'html'.
+ */
+function ajax_forms_test_advanced_commands_html_callback($form, FormStateInterface $form_state) {
+  $response = new AjaxResponse();
+  $response->addCommand(new Ajax\HtmlCommand('#html_div', 'replacement text'));
+  return $response;
+}
+
+/**
+ * Ajax form callback: Selects 'insert'.
+ */
+function ajax_forms_test_advanced_commands_insert_callback($form, FormStateInterface $form_state) {
+  $response = new AjaxResponse();
+  $response->addCommand(new Ajax\InsertCommand('#insert_div', 'insert replacement text'));
+  return $response;
+}
+
+/**
+ * Ajax form callback: Selects 'prepend'.
+ */
+function ajax_forms_test_advanced_commands_prepend_callback($form, FormStateInterface $form_state) {
+  $response = new AjaxResponse();
+  $response->addCommand(new Ajax\PrependCommand('#prepend_div', "prepended text"));
+  return $response;
+}
+
+/**
+ * Ajax form callback: Selects 'remove'.
+ */
+function ajax_forms_test_advanced_commands_remove_callback($form, FormStateInterface $form_state) {
+  $response = new AjaxResponse();
+  $response->addCommand(new Ajax\RemoveCommand('#remove_text'));
+  return $response;
+}
+
+/**
+ * Ajax form callback: Selects 'restripe'.
+ */
+function ajax_forms_test_advanced_commands_restripe_callback($form, FormStateInterface $form_state) {
+  $response = new AjaxResponse();
+  $response->addCommand(new Ajax\RestripeCommand('#restripe_table'));
+  return $response;
+}
+
+/**
+ * Ajax form callback: Selects 'settings'.
+ */
+function ajax_forms_test_advanced_commands_settings_callback($form, FormStateInterface $form_state) {
+  $setting['ajax_forms_test']['foo'] = 42;
+  $response = new AjaxResponse();
+  $response->addCommand(new Ajax\SettingsCommand($setting));
+  return $response;
+}
+
+/**
+ * Ajax callback for 'add_css'.
+ */
+function ajax_forms_test_advanced_commands_add_css_callback($form, FormStateInterface $form_state) {
+  $response = new AjaxResponse();
+  $response->addCommand(new Ajax\AddCssCommand('my/file.css'));
+  return $response;
+}
+
+/**
+ * Ajax form callback: Selects the 'drivertext' element of the validation form.
+ */
+function ajax_forms_test_validation_form_callback($form, FormStateInterface $form_state) {
+  drupal_set_message("ajax_forms_test_validation_form_callback invoked");
+  drupal_set_message(t("Callback: drivertext=%drivertext, spare_required_field=%spare_required_field", array('%drivertext' => $form_state->getValue('drivertext'), '%spare_required_field' => $form_state->getValue('spare_required_field'))));
+  return ['#markup' => '<div id="message_area">ajax_forms_test_validation_form_callback at ' . date('c') . '</div>'];
+}
+
+/**
+ * Ajax form callback: Selects the 'drivernumber' element of the validation form.
+ */
+function ajax_forms_test_validation_number_form_callback($form, FormStateInterface $form_state) {
+  drupal_set_message("ajax_forms_test_validation_number_form_callback invoked");
+  drupal_set_message(t("Callback: drivernumber=%drivernumber, spare_required_field=%spare_required_field", array('%drivernumber' => $form_state->getValue('drivernumber'), '%spare_required_field' => $form_state->getValue('spare_required_field'))));
+  return ['#markup' => '<div id="message_area_number">ajax_forms_test_validation_number_form_callback at ' . date('c') . '</div>'];
+}
+
+/**
+ * AJAX form callback: Selects for the ajax_forms_test_lazy_load_form() form.
+ */
+function ajax_forms_test_lazy_load_form_ajax($form, FormStateInterface $form_state) {
+  $build = [
+    '#markup' => 'new content',
+  ];
+
+  if ($form_state->getValue('add_files')) {
+    $build['#attached']['library'][] = 'system/admin';
+    $build['#attached']['library'][] = 'system/drupal.system';
+    $build['#attached']['drupalSettings']['ajax_forms_test_lazy_load_form_submit'] = 'executed';
+  }
+
+  return $build;
+}

core/modules/system/tests/modules/ajax_forms_test/ajax_forms_test.routing.yml

@@ -0,0 +1,39 @@
+ajax_forms_test.get_form:
+  path: '/ajax_forms_test_get_form'
+  defaults:
+    _title: 'AJAX forms simple form test'
+    _form: '\Drupal\ajax_forms_test\Form\AjaxFormsTestSimpleForm'
+  requirements:
+    _access: 'TRUE'
+
+ajax_forms_test.commands_form:
+  path: '/ajax_forms_test_ajax_commands_form'
+  defaults:
+    _title: 'AJAX forms AJAX commands test'
+    _form: '\Drupal\ajax_forms_test\Form\AjaxFormsTestCommandsForm'
+  requirements:
+    _access: 'TRUE'
+
+ajax_forms_test.validation_test:
+  path: '/ajax_validation_test'
+  defaults:
+    _title: 'AJAX Validation Test'
+    _form: '\Drupal\ajax_forms_test\Form\AjaxFormsTestValidationForm'
+  requirements:
+    _access: 'TRUE'
+
+ajax_forms_test.lazy_load_form:
+  path: '/ajax_forms_test_lazy_load_form'
+  defaults:
+    _title: 'AJAX forms lazy load test'
+    _form: '\Drupal\ajax_forms_test\Form\AjaxFormsTestLazyLoadForm'
+  requirements:
+    _access: 'TRUE'
+
+ajax_forms_test.cached_form:
+  path: '/ajax_forms_test_cached_form'
+  defaults:
+    _title: 'AJAX forms cached form test'
+    _form: '\Drupal\ajax_forms_test\Form\AjaxFormsTestCachedForm'
+  requirements:
+    _access: 'TRUE'

core/modules/system/tests/modules/ajax_forms_test/src/Callbacks.php

@@ -0,0 +1,39 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\ajax_forms_test\Callbacks.
+ */
+
+namespace Drupal\ajax_forms_test;
+
+use Drupal\Core\Ajax\AjaxResponse;
+use Drupal\Core\Ajax\DataCommand;
+use Drupal\Core\Ajax\HtmlCommand;
+use Drupal\Core\Form\FormStateInterface;
+
+/**
+ * Simple object for testing methods as Ajax callbacks.
+ */
+class Callbacks {
+
+  /**
+   * Ajax callback triggered by select.
+   */
+  function selectCallback($form, FormStateInterface $form_state) {
+    $response = new AjaxResponse();
+    $response->addCommand(new HtmlCommand('#ajax_selected_color', $form_state->getValue('select')));
+    $response->addCommand(new DataCommand('#ajax_selected_color', 'form_state_value_select', $form_state->getValue('select')));
+    return $response;
+  }
+
+  /**
+   * Ajax callback triggered by checkbox.
+   */
+  function checkboxCallback($form, FormStateInterface $form_state) {
+    $response = new AjaxResponse();
+    $response->addCommand(new HtmlCommand('#ajax_checkbox_value', (int) $form_state->getValue('checkbox')));
+    $response->addCommand(new DataCommand('#ajax_checkbox_value', 'form_state_value_select', (int) $form_state->getValue('checkbox')));
+    return $response;
+  }
+}

core/modules/system/tests/modules/ajax_forms_test/src/Form/AjaxFormsTestCachedForm.php

@@ -0,0 +1,50 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\ajax_forms_test\Form\AjaxFormsTestCachedForm.
+ */
+
+namespace Drupal\ajax_forms_test\Form;
+
+use Drupal\Core\Form\FormBase;
+use Drupal\Core\Form\FormStateInterface;
+use Drupal\Core\Url;
+
+/**
+ * Provides an AJAX form that will be cached.
+ */
+class AjaxFormsTestCachedForm extends FormBase {
+
+  /**
+   * {@inheritdoc}
+   */
+  public function getFormId() {
+    return 'ajax_form_cache_test_form';
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function buildForm(array $form, FormStateInterface $form_state) {
+    $form['test1'] = [
+      '#type' => 'select',
+      '#title' => $this->t('Test 1'),
+      '#options' => [
+        'option1' => $this->t('Option 1'),
+        'option2' => $this->t('Option 2'),
+      ],
+      '#ajax' => [
+        'url' => Url::fromRoute('system.ajax'),
+      ],
+    ];
+    return $form;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function submitForm(array &$form, FormStateInterface $form_state) {
+  }
+
+}

core/modules/system/tests/modules/ajax_forms_test/src/Form/AjaxFormsTestCommandsForm.php

@@ -0,0 +1,211 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\ajax_forms_test\Form\AjaxFormsTestCommandsForm.
+ */
+
+namespace Drupal\ajax_forms_test\Form;
+
+use Drupal\Core\Form\FormBase;
+use Drupal\Core\Form\FormStateInterface;
+
+/**
+ * Form constructor for the Ajax Command display form.
+ */
+class AjaxFormsTestCommandsForm extends FormBase {
+
+  /**
+   * {@inheritdoc}.
+   */
+  public function getFormId() {
+    return 'ajax_forms_test_ajax_commands_form';
+  }
+
+  /**
+   * {@inheritdoc}.
+   */
+  public function buildForm(array $form, FormStateInterface $form_state) {
+    $form = array();
+
+    // Shows the 'after' command with a callback generating commands.
+    $form['after_command_example'] = array(
+      '#value' => $this->t("AJAX 'After': Click to put something after the div"),
+      '#type' => 'submit',
+      '#ajax' => array(
+        'callback' => 'ajax_forms_test_advanced_commands_after_callback',
+      ),
+      '#suffix' => '<div id="after_div">Something can be inserted after this</div>',
+    );
+
+    // Shows the 'alert' command.
+    $form['alert_command_example'] = array(
+      '#value' => $this->t("AJAX 'Alert': Click to alert"),
+      '#type' => 'submit',
+      '#ajax' => array(
+        'callback' => 'ajax_forms_test_advanced_commands_alert_callback',
+      ),
+    );
+
+    // Shows the 'append' command.
+    $form['append_command_example'] = array(
+      '#value' => $this->t("AJAX 'Append': Click to append something"),
+      '#type' => 'submit',
+      '#ajax' => array(
+        'callback' => 'ajax_forms_test_advanced_commands_append_callback',
+      ),
+      '#suffix' => '<div id="append_div">Append inside this div</div>',
+    );
+
+
+    // Shows the 'before' command.
+    $form['before_command_example'] = array(
+      '#value' => $this->t("AJAX 'before': Click to put something before the div"),
+      '#type' => 'submit',
+      '#ajax' => array(
+        'callback' => 'ajax_forms_test_advanced_commands_before_callback',
+      ),
+      '#suffix' => '<div id="before_div">Insert something before this.</div>',
+    );
+
+    // Shows the 'changed' command without asterisk.
+    $form['changed_command_example'] = array(
+      '#value' => $this->t("AJAX changed: Click to mark div changed."),
+      '#type' => 'submit',
+      '#ajax' => array(
+        'callback' => 'ajax_forms_test_advanced_commands_changed_callback',
+      ),
+      '#suffix' => '<div id="changed_div"> <div id="changed_div_mark_this">This div can be marked as changed or not.</div></div>',
+    );
+    // Shows the 'changed' command adding the asterisk.
+    $form['changed_command_asterisk_example'] = array(
+      '#value' => $this->t("AJAX changed: Click to mark div changed with asterisk."),
+      '#type' => 'submit',
+      '#ajax' => array(
+        'callback' => 'ajax_forms_test_advanced_commands_changed_asterisk_callback',
+      ),
+    );
+
+    // Shows the Ajax 'css' command.
+    $form['css_command_example'] = array(
+      '#value' => $this->t("Set the '#box' div to be blue."),
+      '#type' => 'submit',
+      '#ajax' => array(
+        'callback' => 'ajax_forms_test_advanced_commands_css_callback',
+      ),
+      '#suffix' => '<div id="css_div" style="height: 50px; width: 50px; border: 1px solid black"> box</div>',
+    );
+
+
+    // Shows the Ajax 'data' command. But there is no use of this information,
+    // as this would require a javascript client to use the data.
+    $form['data_command_example'] = array(
+      '#value' => $this->t("AJAX data command: Issue command."),
+      '#type' => 'submit',
+      '#ajax' => array(
+        'callback' => 'ajax_forms_test_advanced_commands_data_callback',
+      ),
+      '#suffix' => '<div id="data_div">Data attached to this div.</div>',
+    );
+
+    // Shows the Ajax 'invoke' command.
+    $form['invoke_command_example'] = array(
+      '#value' => $this->t("AJAX invoke command: Invoke addClass() method."),
+      '#type' => 'submit',
+      '#ajax' => array(
+        'callback' => 'ajax_forms_test_advanced_commands_invoke_callback',
+      ),
+      '#suffix' => '<div id="invoke_div">Original contents</div>',
+    );
+
+    // Shows the Ajax 'html' command.
+    $form['html_command_example'] = array(
+      '#value' => $this->t("AJAX html: Replace the HTML in a selector."),
+      '#type' => 'submit',
+      '#ajax' => array(
+        'callback' => 'ajax_forms_test_advanced_commands_html_callback',
+      ),
+      '#suffix' => '<div id="html_div">Original contents</div>',
+    );
+
+    // Shows the Ajax 'insert' command.
+    $form['insert_command_example'] = array(
+      '#value' => $this->t("AJAX insert: Let client insert based on #ajax['method']."),
+      '#type' => 'submit',
+      '#ajax' => array(
+        'callback' => 'ajax_forms_test_advanced_commands_insert_callback',
+        'method' => 'prepend',
+      ),
+      '#suffix' => '<div id="insert_div">Original contents</div>',
+    );
+
+    // Shows the Ajax 'prepend' command.
+    $form['prepend_command_example'] = array(
+      '#value' => $this->t("AJAX 'prepend': Click to prepend something"),
+      '#type' => 'submit',
+      '#ajax' => array(
+        'callback' => 'ajax_forms_test_advanced_commands_prepend_callback',
+      ),
+      '#suffix' => '<div id="prepend_div">Something will be prepended to this div. </div>',
+    );
+
+    // Shows the Ajax 'remove' command.
+    $form['remove_command_example'] = array(
+      '#value' => $this->t("AJAX 'remove': Click to remove text"),
+      '#type' => 'submit',
+      '#ajax' => array(
+        'callback' => 'ajax_forms_test_advanced_commands_remove_callback',
+      ),
+      '#suffix' => '<div id="remove_div"><div id="remove_text">text to be removed</div></div>',
+    );
+
+    // Shows the Ajax 'restripe' command.
+    $form['restripe_command_example'] = array(
+      '#type' => 'submit',
+      '#value' => $this->t("AJAX 'restripe' command"),
+      '#ajax' => array(
+        'callback' => 'ajax_forms_test_advanced_commands_restripe_callback',
+      ),
+      '#suffix' => '<div id="restripe_div">
+                    <table id="restripe_table" style="border: 1px solid black" >
+                    <tr id="table-first"><td>first row</td></tr>
+                    <tr ><td>second row</td></tr>
+                    </table>
+                    </div>',
+    );
+
+    // Demonstrates the Ajax 'settings' command. The 'settings' command has
+    // nothing visual to "show", but it can be tested via SimpleTest and via
+    // Firebug.
+    $form['settings_command_example'] = array(
+      '#type' => 'submit',
+      '#value' => $this->t("AJAX 'settings' command"),
+      '#ajax' => array(
+        'callback' => 'ajax_forms_test_advanced_commands_settings_callback',
+      ),
+    );
+
+    // Shows the Ajax 'add_css' command.
+    $form['add_css_command_example'] = array(
+      '#type' => 'submit',
+      '#value' => $this->t("AJAX 'add_css' command"),
+      '#ajax' => array(
+        'callback' => 'ajax_forms_test_advanced_commands_add_css_callback',
+      ),
+    );
+
+    $form['submit'] = array(
+      '#type' => 'submit',
+      '#value' => $this->t('Submit'),
+    );
+
+    return $form;
+  }
+
+  /**
+   * {@inheritdoc}.
+   */
+  public function submitForm(array &$form, FormStateInterface $form_state) {
+  }
+
+}

core/modules/system/tests/modules/ajax_forms_test/src/Form/AjaxFormsTestLazyLoadForm.php

@@ -0,0 +1,59 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\ajax_forms_test\Form\AjaxFormsTestLazyLoadForm.
+ */
+
+namespace Drupal\ajax_forms_test\Form;
+
+use Drupal\Core\Form\FormBase;
+use Drupal\Core\Form\FormStateInterface;
+
+/**
+ * Form builder: Builds a form that triggers a simple AJAX callback.
+ */
+class AjaxFormsTestLazyLoadForm extends FormBase {
+
+  /**
+   * {@inheritdoc}
+   */
+  public function getFormId() {
+    return 'ajax_forms_test_lazy_load_form';
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function buildForm(array $form, FormStateInterface $form_state) {
+    // We attach a JavaScript setting, so that one of the generated AJAX
+    // commands will be a settings command. We can then check the settings
+    // command to ensure that the 'currentPath' setting is not part
+    // of the Ajax response.
+    $form['#attached']['drupalSettings']['test'] = 'currentPathUpdate';
+    $form['add_files'] = array(
+      '#title' => $this->t('Add files'),
+      '#type' => 'checkbox',
+      '#default_value' => FALSE,
+    );
+    $form['submit'] = array(
+      '#type' => 'submit',
+      '#value' => $this->t('Submit'),
+      '#ajax' => array(
+        'wrapper' => 'ajax-forms-test-lazy-load-ajax-wrapper',
+        'callback' => 'ajax_forms_test_lazy_load_form_ajax',
+      ),
+      '#prefix' => '<div id="ajax-forms-test-lazy-load-ajax-wrapper"></div>',
+    );
+
+    return $form;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function submitForm(array &$form, FormStateInterface $form_state) {
+    $form_state->setRebuild();
+  }
+
+}

core/modules/system/tests/modules/ajax_forms_test/src/Form/AjaxFormsTestSimpleForm.php

@@ -0,0 +1,84 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\ajax_forms_test\Form\AjaxFormsTestSimpleForm.
+ */
+
+namespace Drupal\ajax_forms_test\Form;
+
+use Drupal\Core\Form\FormBase;
+use Drupal\ajax_forms_test\Callbacks;
+use Drupal\Core\Form\FormStateInterface;
+
+/**
+ * Form builder: Builds a form that triggers a simple AJAX callback.
+ */
+class AjaxFormsTestSimpleForm extends FormBase {
+
+  /**
+   * {@inheritdoc}
+   */
+  public function getFormId() {
+    return 'ajax_forms_test_simple_form';
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function buildForm(array $form, FormStateInterface $form_state) {
+    $object = new Callbacks();
+
+    $form = array();
+    $form['select'] = array(
+      '#title' => $this->t('Color'),
+      '#type' => 'select',
+      '#options' => array(
+        'red' => 'red',
+        'green' => 'green',
+        'blue' => 'blue'),
+      '#ajax' => array(
+        'callback' => array($object, 'selectCallback'),
+      ),
+      '#suffix' => '<div id="ajax_selected_color">No color yet selected</div>',
+    );
+
+    $form['checkbox'] = array(
+      '#type' => 'checkbox',
+      '#title' => $this->t('Test checkbox'),
+      '#ajax' => array(
+        'callback' => array($object, 'checkboxCallback'),
+      ),
+      '#suffix' => '<div id="ajax_checkbox_value">No action yet</div>',
+    );
+    $form['submit'] = array(
+      '#type' => 'submit',
+      '#value' => $this->t('submit'),
+    );
+
+    // This is for testing invalid callbacks that should return a 500 error in
+    // \Drupal\system\FormAjaxController::content().
+    $invalid_callbacks = array(
+      'null' => NULL,
+      'empty' => '',
+      'nonexistent' => 'some_function_that_does_not_exist',
+    );
+    foreach ($invalid_callbacks as $key => $value) {
+      $form['select_' . $key . '_callback'] = array(
+        '#type' => 'select',
+        '#title' => $this->t('Test %key callbacks', array('%key' => $key)),
+        '#options' => array('red' => 'red'),
+        '#ajax' => array('callback' => $value),
+      );
+    }
+
+    return $form;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function submitForm(array &$form, FormStateInterface $form_state) {
+  }
+
+}

core/modules/system/tests/modules/ajax_forms_test/src/Form/AjaxFormsTestValidationForm.php

@@ -0,0 +1,76 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\ajax_forms_test\Form\AjaxFormsTestValidationForm.
+ */
+
+namespace Drupal\ajax_forms_test\Form;
+
+use Drupal\Core\Form\FormBase;
+use Drupal\Core\Form\FormStateInterface;
+
+/**
+ * Form builder: Builds a form that triggers a simple AJAX callback.
+ */
+class AjaxFormsTestValidationForm extends FormBase {
+
+  /**
+   * {@inheritdoc}
+   */
+  public function getFormId() {
+    return 'ajax_forms_test_validation_form';
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function buildForm(array $form, FormStateInterface $form_state) {
+    $form['drivertext'] = array(
+      '#title' => $this->t('AJAX-enabled textfield.'),
+      '#description' => $this->t("When this one AJAX-triggers and the spare required field is empty, you should not get an error."),
+      '#type' => 'textfield',
+      '#default_value' => $form_state->getValue('drivertext', ''),
+      '#ajax' => array(
+        'callback' => 'ajax_forms_test_validation_form_callback',
+        'wrapper' => 'message_area',
+        'method' => 'replace',
+      ),
+      '#suffix' => '<div id="message_area"></div>',
+    );
+
+    $form['drivernumber'] = array(
+      '#title' => $this->t('AJAX-enabled number field.'),
+      '#description' => $this->t("When this one AJAX-triggers and the spare required field is empty, you should not get an error."),
+      '#type' => 'number',
+      '#default_value' => $form_state->getValue('drivernumber', ''),
+      '#ajax' => array(
+        'callback' => 'ajax_forms_test_validation_number_form_callback',
+        'wrapper' => 'message_area_number',
+        'method' => 'replace',
+      ),
+      '#suffix' => '<div id="message_area_number"></div>',
+    );
+
+    $form['spare_required_field'] = array(
+      '#title' => $this->t("Spare Required Field"),
+      '#type' => 'textfield',
+      '#required' => TRUE,
+    );
+
+    $form['submit'] = array(
+      '#type' => 'submit',
+      '#value' => $this->t('Submit'),
+    );
+
+    return $form;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function submitForm(array &$form, FormStateInterface $form_state) {
+    drupal_set_message($this->t("Validation form submitted"));
+  }
+
+}

core/modules/system/tests/modules/ajax_forms_test/src/Plugin/Block/AjaxFormBlock.php

@@ -0,0 +1,140 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\ajax_forms_test\Plugin\Block\AjaxFormBlock.
+ */
+
+namespace Drupal\ajax_forms_test\Plugin\Block;
+
+use Drupal\Core\Block\BlockBase;
+use Drupal\Core\Form\FormBuilderInterface;
+use Drupal\Core\Form\FormInterface;
+use Drupal\Core\Form\FormStateInterface;
+use Drupal\Core\Plugin\ContainerFactoryPluginInterface;
+use Symfony\Component\DependencyInjection\ContainerInterface;
+
+/**
+ * Provides an AJAX form block.
+ *
+ * @Block(
+ *   id = "ajax_forms_test_block",
+ *   admin_label = @Translation("AJAX test form"),
+ *   category = @Translation("Forms")
+ * )
+ */
+class AjaxFormBlock extends BlockBase implements FormInterface, ContainerFactoryPluginInterface {
+
+  /**
+   * The form builder.
+   *
+   * @var \Drupal\Core\Form\FormBuilderInterface
+   */
+  protected $formBuilder;
+
+  /**
+   * Constructs a new AjaxFormBlock.
+   *
+   * @param array $configuration
+   *   A configuration array containing information about the plugin instance.
+   * @param string $plugin_id
+   *   The plugin ID for the plugin instance.
+   * @param mixed $plugin_definition
+   *   The plugin implementation definition.
+   * @param \Drupal\Core\Form\FormBuilderInterface $form_builder
+   *   The form builder.
+   */
+  public function __construct(array $configuration, $plugin_id, $plugin_definition, FormBuilderInterface $form_builder) {
+    parent::__construct($configuration, $plugin_id, $plugin_definition);
+    $this->formBuilder = $form_builder;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public static function create(ContainerInterface $container, array $configuration, $plugin_id, $plugin_definition) {
+    return new static(
+      $configuration,
+      $plugin_id,
+      $plugin_definition,
+      $container->get('form_builder')
+    );
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function build() {
+    return $this->formBuilder->getForm($this);
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function getFormId() {
+    return 'ajax_forms_test_block';
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function buildForm(array $form, FormStateInterface $form_state) {
+    $form['test1'] = [
+      '#type' => 'select',
+      '#title' => $this->t('Test 1'),
+      '#required' => TRUE,
+      '#options' => [
+        'option1' => $this->t('Option 1'),
+        'option2' => $this->t('Option 2'),
+      ],
+      '#ajax' => [
+        'callback' => '::updateOptions',
+        'wrapper' => 'edit-test1-wrapper',
+      ],
+      '#prefix' => '<div id="edit-test1-wrapper">',
+      '#suffix' => '</div>',
+    ];
+    $form['actions'] = [
+      '#type' => 'actions',
+    ];
+    $form['actions']['submit'] = [
+      '#type' => 'submit',
+      '#value' => $this->t('Submit'),
+    ];
+    return $form;
+  }
+
+  /**
+   * Updates the options of a select list.
+   *
+   * @param array $form
+   *   An associative array containing the structure of the form.
+   * @param \Drupal\Core\Form\FormStateInterface $form_state
+   *   The current state of the form.
+   *
+   * @return array
+   *   The updated form element.
+   */
+  public function updateOptions(array $form, FormStateInterface $form_state) {
+    $form['test1']['#options']['option1'] = $this->t('Option 1!!!');
+    $form['test1']['#options'] += [
+      'option3' => $this->t('Option 3'),
+      'option4' => $this->t('Option 4'),
+    ];
+    return $form['test1'];
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function validateForm(array &$form, FormStateInterface $form_state) {
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function submitForm(array &$form, FormStateInterface $form_state) {
+    drupal_set_message('Submission successful.');
+  }
+
+}

core/modules/system/tests/modules/ajax_test/ajax_test.info.yml

@@ -0,0 +1,8 @@
+name: 'AJAX Test'
+type: module
+description: 'Support module for AJAX framework tests.'
+package: Testing
+version: VERSION
+core: 8.x
+dependencies:
+  - contact

core/modules/system/tests/modules/ajax_test/ajax_test.libraries.yml

@@ -0,0 +1,23 @@
+order:
+ drupalSettings:
+   ajax: test
+ dependencies:
+   - ajax_test/order-css-command
+   - ajax_test/order-footer-js-command
+   - ajax_test/order-header-js-command
+
+order-css-command:
+  css:
+     theme:
+       # Two CSS files (order should remain the same).
+       a.css: {}
+       b.css: {}
+
+order-footer-js-command:
+  js:
+    footer.js: {}
+
+order-header-js-command:
+  header: true
+  js:
+    header.js: {}

core/modules/system/tests/modules/ajax_test/ajax_test.routing.yml

@@ -0,0 +1,52 @@
+ajax_test.dialog_contents:
+  path: '/ajax-test/dialog-contents'
+  defaults:
+    _title: 'AJAX Dialog contents routing'
+    _controller: '\Drupal\ajax_test\Controller\AjaxTestController::dialogContents'
+  requirements:
+    _access: 'TRUE'
+
+ajax_test.dialog_form:
+  path: '/ajax-test/dialog-form'
+  defaults:
+    _title: 'Ajax Form contents'
+    _form: '\Drupal\ajax_test\Form\AjaxTestForm'
+  requirements:
+    _access: 'TRUE'
+
+ajax_test.dialog:
+  path: '/ajax-test/dialog'
+  defaults:
+    _controller: '\Drupal\ajax_test\Controller\AjaxTestController::dialog'
+  requirements:
+    _access: 'TRUE'
+
+ajax_test.dialog_close:
+  path: '/ajax-test/dialog-close'
+  defaults:
+    _controller: '\Drupal\ajax_test\Controller\AjaxTestController::dialogClose'
+  requirements:
+    _access: 'TRUE'
+
+ajax_test.render:
+  path: '/ajax-test/render'
+  defaults:
+    _controller: '\Drupal\ajax_test\Controller\AjaxTestController::render'
+  requirements:
+    _access: 'TRUE'
+
+ajax_test.order:
+  path: '/ajax-test/order'
+  defaults:
+    _controller: '\Drupal\ajax_test\Controller\AjaxTestController::order'
+  options:
+    _theme: ajax_base_page
+  requirements:
+    _access: 'TRUE'
+
+ajax_test.render_error:
+  path: '/ajax-test/render-error'
+  defaults:
+    _controller: '\Drupal\ajax_test\Controller\AjaxTestController::renderError'
+  requirements:
+    _access: 'TRUE'

core/modules/system/tests/modules/ajax_test/src/Controller/AjaxTestController.php

@@ -0,0 +1,211 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\ajax_test\Controller\AjaxTestController.
+ */
+
+namespace Drupal\ajax_test\Controller;
+
+use Drupal\Core\Ajax\AjaxResponse;
+use Drupal\Core\Ajax\AlertCommand;
+use Drupal\Core\Ajax\CloseDialogCommand;
+use Drupal\Core\Ajax\HtmlCommand;
+use Drupal\Core\Url;
+use Symfony\Component\HttpFoundation\Request;
+
+/**
+ * Provides content for dialog tests.
+ */
+class AjaxTestController {
+
+  /**
+   * Example content for dialog testing.
+   *
+   * @return array
+   *   Renderable array of AJAX dialog contents.
+   */
+  public static function dialogContents() {
+    // This is a regular render array; the keys do not have special meaning.
+    $content = array(
+      '#title' => 'AJAX Dialog contents',
+      'content' => array(
+        '#markup' => 'Example message',
+      ),
+      'cancel' => array(
+        '#type' => 'link',
+        '#title' => 'Cancel',
+        '#url' => Url::fromRoute('<front>'),
+        '#attributes' => array(
+          // This is a special class to which JavaScript assigns dialog closing
+          // behavior.
+          'class' => array('dialog-cancel'),
+        ),
+      ),
+    );
+
+    return $content;
+  }
+
+  /**
+   * Returns a render array that will be rendered by AjaxRenderer.
+   *
+   * Ensures that \Drupal\Core\Ajax\AjaxResponse::ajaxRender()
+   * incorporates JavaScript settings generated during the page request by
+   * adding a dummy setting.
+   */
+  public function render() {
+    return [
+      '#attached' => [
+        'library' => [
+          'core/drupalSettings',
+        ],
+        'drupalSettings' => [
+          'ajax' => 'test',
+        ],
+      ],
+    ];
+  }
+
+  /**
+   * Returns an AjaxResponse; settings command set last.
+   *
+   * Helps verifying AjaxResponse reorders commands to ensure correct execution.
+   */
+  public function order() {
+    $response = new AjaxResponse();
+    // HTML insertion command.
+    $response->addCommand(new HtmlCommand('body', 'Hello, world!'));
+    $build['#attached']['library'][] = 'ajax_test/order';
+    $response->setAttachments($build['#attached']);
+
+    return $response;
+  }
+
+  /**
+   * Returns an AjaxResponse with alert command.
+   *
+   * @param \Symfony\Component\HttpFoundation\Request $request
+   *   The current request object.
+   *
+   * @return \Drupal\Core\Ajax\AjaxResponse
+   *   The JSON response object.
+   */
+  public function renderError(Request $request) {
+    $message = '';
+    $query = $request->query;
+    if ($query->has('message')) {
+      $message = $query->get('message');
+    }
+    $response = new AjaxResponse();
+    $response->addCommand(new AlertCommand($message));
+    return $response;
+  }
+
+  /**
+   * Returns a render array of form elements and links for dialog.
+   */
+  public function dialog() {
+    // Add two wrapper elements for testing non-modal dialogs. Modal dialogs use
+    // the global drupal-modal wrapper by default.
+    $build['dialog_wrappers'] = array('#markup' => '<div id="ajax-test-dialog-wrapper-1"></div><div id="ajax-test-dialog-wrapper-2"></div>');
+
+    // Dialog behavior applied to a button.
+    $build['form'] = \Drupal::formBuilder()->getForm('Drupal\ajax_test\Form\AjaxTestDialogForm');
+
+    // Dialog behavior applied to a #type => 'link'.
+    $build['link'] = array(
+      '#type' => 'link',
+      '#title' => 'Link 1 (modal)',
+      '#url' => Url::fromRoute('ajax_test.dialog_contents'),
+      '#attributes' => array(
+        'class' => array('use-ajax'),
+        'data-dialog-type' => 'modal',
+      ),
+    );
+
+    // Dialog behavior applied to links rendered by links.html.twig.
+    $build['links'] = array(
+      '#theme' => 'links',
+      '#links' => array(
+        'link2' => array(
+          'title' => 'Link 2 (modal)',
+          'url' => Url::fromRoute('ajax_test.dialog_contents'),
+          'attributes' => array(
+            'class' => array('use-ajax'),
+            'data-dialog-type' => 'modal',
+            'data-dialog-options' => json_encode(array(
+              'width' => 400,
+            ))
+          ),
+        ),
+        'link3' => array(
+          'title' => 'Link 3 (non-modal)',
+          'url' => Url::fromRoute('ajax_test.dialog_contents'),
+          'attributes' => array(
+            'class' => array('use-ajax'),
+            'data-dialog-type' => 'dialog',
+            'data-dialog-options' => json_encode(array(
+              'target' => 'ajax-test-dialog-wrapper-1',
+              'width' => 800,
+            ))
+          ),
+        ),
+        'link4' => array(
+          'title' => 'Link 4 (close non-modal if open)',
+          'url' => Url::fromRoute('ajax_test.dialog_close'),
+          'attributes' => array(
+            'class' => array('use-ajax'),
+            'data-dialog-type' => 'modal',
+          ),
+        ),
+        'link5' => array(
+          'title' => 'Link 5 (form)',
+          'url' => Url::fromRoute('ajax_test.dialog_form'),
+          'attributes' => array(
+            'class' => array('use-ajax'),
+            'data-dialog-type' => 'modal',
+          ),
+        ),
+        'link6' => array(
+          'title' => 'Link 6 (entity form)',
+          'url' => Url::fromRoute('contact.form_add'),
+          'attributes' => array(
+            'class' => array('use-ajax'),
+            'data-dialog-type' => 'modal',
+            'data-dialog-options' => json_encode(array(
+              'width' => 800,
+              'height' => 500,
+            ))
+          ),
+        ),
+        'link7' => array(
+          'title' => 'Link 7 (non-modal, no target)',
+          'url' => Url::fromRoute('ajax_test.dialog_contents'),
+          'attributes' => array(
+            'class' => array('use-ajax'),
+            'data-dialog-type' => 'dialog',
+            'data-dialog-options' => json_encode(array(
+              'width' => 800,
+            ))
+          ),
+        ),
+      ),
+    );
+
+    return $build;
+  }
+
+  /**
+   * Returns an AjaxResponse with command to close dialog.
+   *
+   * @return \Drupal\Core\Ajax\AjaxResponse
+   *   The JSON response object.
+   */
+  public function dialogClose() {
+    $response = new AjaxResponse();
+    $response->addCommand(new CloseDialogCommand('#ajax-test-dialog-wrapper-1'));
+    return $response;
+  }
+
+}

core/modules/system/tests/modules/ajax_test/src/Form/AjaxTestDialogForm.php

@@ -0,0 +1,117 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\ajax_test\Form\AjaxTestDialogForm.
+ */
+
+namespace Drupal\ajax_test\Form;
+
+use Drupal\ajax_test\Controller\AjaxTestController;
+use Drupal\Core\Form\FormBase;
+use Drupal\Core\Ajax\AjaxResponse;
+use Drupal\Core\Ajax\OpenModalDialogCommand;
+use Drupal\Core\Ajax\OpenDialogCommand;
+use Drupal\Core\Form\FormStateInterface;
+
+/**
+ * Dummy form for testing DialogRenderer with _form routes.
+ */
+class AjaxTestDialogForm extends FormBase {
+
+  /**
+   * {@inheritdoc}
+   */
+  public function getFormId() {
+    return 'ajax_test_dialog_form';
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function buildForm(array $form, FormStateInterface $form_state) {
+    // In order to use WebTestBase::drupalPostAjaxForm() to POST from a link, we need
+    // to have a dummy field we can set in WebTestBase::drupalPostForm() else it won't
+    // submit anything.
+    $form['textfield'] = array(
+      '#type' => 'hidden'
+    );
+    $form['button1'] = array(
+      '#type' => 'submit',
+      '#name' => 'button1',
+      '#value' => 'Button 1 (modal)',
+      '#ajax' => array(
+        'callback' => '::modal',
+      ),
+    );
+    $form['button2'] = array(
+      '#type' => 'submit',
+      '#name' => 'button2',
+      '#value' => 'Button 2 (non-modal)',
+      '#ajax' => array(
+        'callback' => '::nonModal',
+      ),
+    );
+
+    return $form;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function validateForm(array &$form, FormStateInterface $form_state) {
+
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function submitForm(array &$form, FormStateInterface $form_state) {
+    $form_state->setRedirect('ajax_test.dialog_contents');
+  }
+
+
+  /**
+   * AJAX callback handler for AjaxTestDialogForm.
+   */
+  public function modal(&$form, FormStateInterface $form_state) {
+    return $this->dialog(TRUE);
+  }
+
+  /**
+   * AJAX callback handler for AjaxTestDialogForm.
+   */
+  public function nonModal(&$form, FormStateInterface $form_state) {
+    return $this->dialog(FALSE);
+  }
+
+
+  /**
+   * Util to render dialog in ajax callback.
+   *
+   * @param bool $is_modal
+   *   (optional) TRUE if modal, FALSE if plain dialog. Defaults to FALSE.
+   *
+   * @return \Drupal\Core\Ajax\AjaxResponse
+   *   An ajax response object.
+   */
+  protected function dialog($is_modal = FALSE) {
+    $content = AjaxTestController::dialogContents();
+    $response = new AjaxResponse();
+    $title = $this->t('AJAX Dialog contents');
+
+    // Attach the library necessary for using the Open(Modal)DialogCommand and
+    // set the attachments for this Ajax response.
+    $content['#attached']['library'][] = 'core/drupal.dialog.ajax';
+
+    if ($is_modal) {
+      $response->addCommand(new OpenModalDialogCommand($title, $content));
+    }
+    else {
+      $selector = '#ajax-test-dialog-wrapper-1';
+      $response->addCommand(new OpenDialogCommand($selector, $title, $content));
+    }
+    return $response;
+  }
+
+}

core/modules/system/tests/modules/ajax_test/src/Form/AjaxTestForm.php

@@ -0,0 +1,74 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\ajax_test\Form\AjaxTestForm.
+ */
+
+namespace Drupal\ajax_test\Form;
+
+use Drupal\Core\Form\FormBase;
+use Drupal\Core\Form\FormStateInterface;
+
+/**
+ * Dummy form for testing DialogRenderer with _form routes.
+ */
+class AjaxTestForm extends FormBase {
+
+  /**
+   * {@inheritdoc}
+   */
+  public function getFormId() {
+    return 'ajax_test_form';
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function buildForm(array $form, FormStateInterface $form_state) {
+
+    $form['#action'] = \Drupal::url('ajax_test.dialog');
+
+    $form['description'] = array(
+      '#markup' => '<p>' . $this->t("Ajax Form contents description.") . '</p>',
+    );
+
+    $form['actions'] = array(
+      '#type' => 'actions',
+    );
+    $form['actions']['submit'] = array(
+      '#type' => 'submit',
+      '#value' => $this->t('Do it'),
+    );
+    $form['actions']['preview'] = array(
+      '#type' => 'submit',
+      '#value' => $this->t('Preview'),
+      // No regular submit-handler. This form only works via JavaScript.
+      '#submit' => array(),
+      '#ajax' => array(
+        // This means the ::preview() method on this class would be invoked in
+        // case of a click event. However, since Drupal core's test runner only
+        // is able to execute PHP, not JS, there is no point in actually
+        // implementing this method, because we can never let it be called from
+        // JS; we'd have to manually call it from PHP, at which point we would
+        // not actually be testing it.
+        // Therefore we consciously choose to not implement this method, because
+        // we cannot meaningfully test it anyway.
+        'callback' => '::preview',
+        'event' => 'click',
+      ),
+    );
+    return $form;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function submitForm(array &$form, FormStateInterface $form_state) {}
+
+  /**
+   * {@inheritdoc}
+   */
+  public function validateForm(array &$form, FormStateInterface $form_state) {}
+
+}

core/modules/system/tests/modules/batch_test/batch_test.callbacks.inc

@@ -0,0 +1,160 @@
+<?php
+
+/**
+ * @file
+ * Batch callbacks for the Batch API tests.
+ */
+
+use Drupal\Component\Utility\SafeMarkup;
+
+/**
+ * Implements callback_batch_operation().
+ *
+ * Performs a simple batch operation.
+ */
+function _batch_test_callback_1($id, $sleep, &$context) {
+  // No-op, but ensure the batch take a couple iterations.
+  // Batch needs time to run for the test, so sleep a bit.
+  usleep($sleep);
+  // Track execution, and store some result for post-processing in the
+  // 'finished' callback.
+  batch_test_stack("op 1 id $id");
+  $context['results'][1][] = $id;
+}
+
+/**
+ * Implements callback_batch_operation().
+ *
+ * Performs a multistep batch operation.
+ */
+function _batch_test_callback_2($start, $total, $sleep, &$context) {
+  // Initialize context with progress information.
+  if (!isset($context['sandbox']['current'])) {
+    $context['sandbox']['current'] = $start;
+    $context['sandbox']['count'] = 0;
+  }
+
+  // Process by groups of 5 (arbitrary value).
+  $limit = 5;
+  for ($i = 0; $i < $limit && $context['sandbox']['count'] < $total; $i++) {
+    // No-op, but ensure the batch take a couple iterations.
+    // Batch needs time to run for the test, so sleep a bit.
+    usleep($sleep);
+    // Track execution, and store some result for post-processing in the
+    // 'finished' callback.
+    $id = $context['sandbox']['current'] + $i;
+    batch_test_stack("op 2 id $id");
+    $context['results'][2][] = $id;
+
+    // Update progress information.
+    $context['sandbox']['count']++;
+  }
+  $context['sandbox']['current'] += $i;
+
+  // Inform batch engine about progress.
+  if ($context['sandbox']['count'] != $total) {
+    $context['finished'] = $context['sandbox']['count'] / $total;
+  }
+}
+
+/**
+ * Implements callback_batch_operation().
+ */
+function _batch_test_callback_5($id, $sleep, &$context) {
+  // No-op, but ensure the batch take a couple iterations.
+  // Batch needs time to run for the test, so sleep a bit.
+  usleep($sleep);
+  // Track execution, and store some result for post-processing in the
+  // 'finished' callback.
+  batch_test_stack("op 5 id $id");
+  $context['results'][5][] = $id;
+  // This test is to test finished > 1
+  $context['finished'] = 3.14;
+}
+
+/**
+ * Implements callback_batch_operation().
+ *
+ * Performs a batch operation setting up its own batch.
+ */
+function _batch_test_nested_batch_callback() {
+  batch_test_stack('setting up batch 2');
+  batch_set(_batch_test_batch_2());
+}
+
+/**
+ * Provides a common 'finished' callback for batches 1 to 4.
+ */
+function _batch_test_finished_helper($batch_id, $success, $results, $operations) {
+  $messages = array("results for batch $batch_id");
+  if ($results) {
+    foreach ($results as $op => $op_results) {
+      $messages[] = 'op '. SafeMarkup::escape($op) . ': processed ' . count($op_results) . ' elements';
+    }
+  }
+  else {
+    $messages[] = 'none';
+  }
+
+  if (!$success) {
+    // A fatal error occurred during the processing.
+    $error_operation = reset($operations);
+    $messages[] = t('An error occurred while processing @op with arguments:<br />@args', array('@op' => $error_operation[0], '@args' => print_r($error_operation[1], TRUE)));
+  }
+
+  drupal_set_message(SafeMarkup::set(implode('<br>', $messages)));
+}
+
+/**
+ * Implements callback_batch_finished().
+ *
+ * Triggers 'finished' callback for batch 0.
+ */
+function _batch_test_finished_0($success, $results, $operations) {
+  _batch_test_finished_helper(0, $success, $results, $operations);
+}
+
+/**
+ * Implements callback_batch_finished().
+ *
+ * Triggers 'finished' callback for batch 1.
+ */
+function _batch_test_finished_1($success, $results, $operations) {
+  _batch_test_finished_helper(1, $success, $results, $operations);
+}
+
+/**
+ * Implements callback_batch_finished().
+ *
+ * Triggers 'finished' callback for batch 2.
+ */
+function _batch_test_finished_2($success, $results, $operations) {
+  _batch_test_finished_helper(2, $success, $results, $operations);
+}
+
+/**
+ * Implements callback_batch_finished().
+ *
+ * Triggers 'finished' callback for batch 3.
+ */
+function _batch_test_finished_3($success, $results, $operations) {
+  _batch_test_finished_helper(3, $success, $results, $operations);
+}
+
+/**
+ * Implements callback_batch_finished().
+ *
+ * Triggers 'finished' callback for batch 4.
+ */
+function _batch_test_finished_4($success, $results, $operations) {
+  _batch_test_finished_helper(4, $success, $results, $operations);
+}
+
+/**
+ * Implements callback_batch_finished().
+ *
+ * Triggers 'finished' callback for batch 5.
+ */
+function _batch_test_finished_5($success, $results, $operations) {
+  _batch_test_finished_helper(5, $success, $results, $operations);
+}

core/modules/system/tests/modules/batch_test/batch_test.info.yml

@@ -0,0 +1,6 @@
+name: 'Batch API test'
+type: module
+description: 'Support module for Batch API tests.'
+package: Testing
+version: VERSION
+core: 8.x

core/modules/system/tests/modules/batch_test/batch_test.links.task.yml

@@ -0,0 +1,46 @@
+batch_test.test_form:
+  title: Simple
+  route_name: batch_test.test_form
+  base_route: batch_test.test_form
+
+batch_test.multistep:
+  title: Multistep
+  route_name: batch_test.multistep
+  base_route: batch_test.test_form
+  weight: 1
+
+batch_test.chained:
+  title: Chained
+  route_name: batch_test.chained
+  base_route: batch_test.test_form
+  weight: 2
+
+batch_test.programmatic:
+  title: Chained
+  route_name: batch_test.programmatic
+  base_route: batch_test.test_form
+  weight: 3
+
+batch_test.no_form:
+  title: 'No form'
+  route_name: batch_test.no_form
+  base_route: batch_test.test_form
+  weight: 4
+
+batch_test.large_percentage:
+  title: 'Large percentage'
+  route_name: batch_test.large_percentage
+  base_route: batch_test.test_form
+  weight: 5
+
+batch_test.nested_programmatic:
+  title: 'Nested programmatic'
+  route_name: batch_test.nested_programmatic
+  base_route: batch_test.test_form
+  weight: 6
+
+batch_test.redirect:
+  title: 'Redirect'
+  route_name: batch_test.redirect
+  base_route: batch_test.test_form
+  weight: 7

core/modules/system/tests/modules/batch_test/batch_test.module

@@ -0,0 +1,199 @@
+<?php
+
+/**
+ * @file
+ * Helper module for the Batch API tests.
+ */
+
+use Drupal\Core\Form\FormState;
+
+/**
+ * Batch operation: Submits form_test_mock_form().
+ */
+function _batch_test_nested_drupal_form_submit_callback($value) {
+  $form_state = (new FormState())
+    ->setValue('test_value', $value);
+  \Drupal::formBuilder()->submitForm('Drupal\batch_test\Form\BatchTestMockForm', $form_state);
+}
+
+/**
+ * Batch 0: Does nothing.
+ */
+function _batch_test_batch_0() {
+  $batch = array(
+    'operations' => array(),
+    'finished' => '_batch_test_finished_0',
+    'file' => drupal_get_path('module', 'batch_test'). '/batch_test.callbacks.inc',
+  );
+  return $batch;
+}
+
+/**
+ * Batch 1: Repeats a simple operation.
+ *
+ * Operations: op 1 from 1 to 10.
+ */
+function _batch_test_batch_1() {
+  // Ensure the batch takes at least two iterations.
+  $total = 10;
+  $sleep = (1000000 / $total) * 2;
+
+  $operations = array();
+  for ($i = 1; $i <= $total; $i++) {
+    $operations[] = array('_batch_test_callback_1', array($i, $sleep));
+  }
+  $batch = array(
+    'operations' => $operations,
+    'finished' => '_batch_test_finished_1',
+    'file' => drupal_get_path('module', 'batch_test'). '/batch_test.callbacks.inc',
+  );
+  return $batch;
+}
+
+/**
+ * Batch 2: Performs a single multistep operation.
+ *
+ * Operations: op 2 from 1 to 10.
+ */
+function _batch_test_batch_2() {
+  // Ensure the batch takes at least two iterations.
+  $total = 10;
+  $sleep = (1000000 / $total) * 2;
+
+  $operations = array(
+    array('_batch_test_callback_2', array(1, $total, $sleep)),
+  );
+  $batch = array(
+    'operations' => $operations,
+    'finished' => '_batch_test_finished_2',
+    'file' => drupal_get_path('module', 'batch_test') . '/batch_test.callbacks.inc',
+  );
+  return $batch;
+}
+
+/**
+ * Batch 3: Performs both single and multistep operations.
+ *
+ * Operations:
+ * - op 1 from 1 to 5,
+ * - op 2 from 1 to 5,
+ * - op 1 from 6 to 10,
+ * - op 2 from 6 to 10.
+ */
+function _batch_test_batch_3() {
+  // Ensure the batch takes at least two iterations.
+  $total = 10;
+  $sleep = (1000000 / $total) * 2;
+
+  $operations = array();
+  for ($i = 1; $i <= round($total / 2); $i++) {
+    $operations[] = array('_batch_test_callback_1', array($i, $sleep));
+  }
+  $operations[] = array('_batch_test_callback_2', array(1, $total / 2, $sleep));
+  for ($i = round($total / 2) + 1; $i <= $total; $i++) {
+    $operations[] = array('_batch_test_callback_1', array($i, $sleep));
+  }
+  $operations[] = array('_batch_test_callback_2', array(6, $total / 2, $sleep));
+  $batch = array(
+    'operations' => $operations,
+    'finished' => '_batch_test_finished_3',
+    'file' => drupal_get_path('module', 'batch_test') . '/batch_test.callbacks.inc',
+  );
+  return $batch;
+}
+
+/**
+ * Batch 4: Performs a batch within a batch.
+ *
+ * Operations:
+ * - op 1 from 1 to 5,
+ * - set batch 2 (op 2 from 1 to 10, should run at the end)
+ * - op 1 from 6 to 10,
+ */
+function _batch_test_batch_4() {
+  // Ensure the batch takes at least two iterations.
+  $total = 10;
+  $sleep = (1000000 / $total) * 2;
+
+  $operations = array();
+  for ($i = 1; $i <= round($total / 2); $i++) {
+    $operations[] = array('_batch_test_callback_1', array($i, $sleep));
+  }
+  $operations[] = array('_batch_test_nested_batch_callback', array());
+  for ($i = round($total / 2) + 1; $i <= $total; $i++) {
+    $operations[] = array('_batch_test_callback_1', array($i, $sleep));
+  }
+  $batch = array(
+    'operations' => $operations,
+    'finished' => '_batch_test_finished_4',
+    'file' => drupal_get_path('module', 'batch_test') . '/batch_test.callbacks.inc',
+  );
+  return $batch;
+}
+
+/**
+ * Batch 5: Repeats a simple operation.
+ *
+ * Operations: op 1 from 1 to 10.
+ */
+function _batch_test_batch_5() {
+  // Ensure the batch takes at least two iterations.
+  $total = 10;
+  $sleep = (1000000 / $total) * 2;
+
+  $operations = array();
+  for ($i = 1; $i <= $total; $i++) {
+    $operations[] = array('_batch_test_callback_5', array($i, $sleep));
+  }
+  $batch = array(
+    'operations' => $operations,
+    'finished' => '_batch_test_finished_5',
+    'file' => drupal_get_path('module', 'batch_test'). '/batch_test.callbacks.inc',
+  );
+  return $batch;
+}
+
+/**
+ * Implements callback_batch_operation().
+ *
+ * Tests the progress page theme.
+ */
+function _batch_test_theme_callback() {
+  // Because drupalGet() steps through the full progressive batch before
+  // returning control to the test function, we cannot test that the correct
+  // theme is being used on the batch processing page by viewing that page
+  // directly. Instead, we save the theme being used in a variable here, so
+  // that it can be loaded and inspected in the thread running the test.
+  $theme = \Drupal::theme()->getActiveTheme()->getName();
+  batch_test_stack($theme);
+}
+
+/**
+ * Tests the title on the progress page by performing a batch callback.
+ */
+function _batch_test_title_callback() {
+  // Because drupalGet() steps through the full progressive batch before
+  // returning control to the test function, we cannot test that the correct
+  // title is being used on the batch processing page by viewing that page
+  // directly. Instead, we save the title being used in a variable here, so
+  // that it can be loaded and inspected in the thread running the test.
+  $request = \Drupal::request();
+  $route_match = \Drupal::routeMatch();
+  $title = \Drupal::service('title_resolver')->getTitle($request, $route_match->getRouteObject());
+  batch_test_stack($title);
+}
+
+/**
+ * Helper function: Stores or retrieves traced execution data.
+ */
+function batch_test_stack($data = NULL, $reset = FALSE) {
+  if ($reset) {
+    \Drupal::state()->delete('batch_test.stack');
+  }
+  if (!isset($data)) {
+    return \Drupal::state()->get('batch_test.stack');
+  }
+  $stack = \Drupal::state()->get('batch_test.stack');
+  $stack[] = $data;
+  \Drupal::state()->set('batch_test.stack', $stack);
+}

core/modules/system/tests/modules/batch_test/batch_test.routing.yml

@@ -0,0 +1,79 @@
+batch_test.redirect:
+  path: '/batch-test/redirect'
+  defaults:
+    _controller: '\Drupal\batch_test\Controller\BatchTestController::testRedirect'
+    _title: 'Redirect'
+  requirements:
+    _access:  'TRUE'
+
+batch_test.large_percentage:
+  path: '/batch-test/large-percentage'
+  defaults:
+    _controller: '\Drupal\batch_test\Controller\BatchTestController::testLargePercentage'
+    _title: 'Simple page with batch over 100% complete'
+  requirements:
+    _access:  'TRUE'
+
+batch_test.nested_programmatic:
+  path: '/batch-test/nested-programmatic/{value}'
+  defaults:
+    _controller: '\Drupal\batch_test\Controller\BatchTestController::testNestedDrupalFormSubmit'
+    _title: 'Nested programmatic'
+    value: '1'
+  requirements:
+    _access: 'TRUE'
+
+batch_test.no_form:
+  path: '/batch-test/no-form'
+  defaults:
+    _controller: '\Drupal\batch_test\Controller\BatchTestController::testNoForm'
+    _title: 'Simple page'
+  requirements:
+    _access: 'TRUE'
+
+batch_test.test_form:
+  path: '/batch-test'
+  defaults:
+    _form: '\Drupal\batch_test\Form\BatchTestSimpleForm'
+    _title: 'Batch test'
+  requirements:
+    _access: 'TRUE'
+
+batch_test.multistep:
+  path: '/batch-test/multistep'
+  defaults:
+    _form: '\Drupal\batch_test\Form\BatchTestMultiStepForm'
+    _title: 'Multistep'
+  requirements:
+    _access: 'TRUE'
+
+batch_test.chained:
+  path: '/batch-test/chained'
+  defaults:
+    _form: '\Drupal\batch_test\Form\BatchTestChainedForm'
+    _title: 'Chained'
+  requirements:
+    _access: 'TRUE'
+
+batch_test.programmatic:
+  path: '/batch-test/programmatic/{value}'
+  defaults:
+    _controller: '\Drupal\batch_test\Controller\BatchTestController::testProgrammatic'
+    _title: 'Programmatic'
+    value: '1'
+  requirements:
+    _access: 'TRUE'
+
+batch_test.test_theme:
+  path: '/admin/batch-test/test-theme'
+  defaults:
+    _controller: '\Drupal\batch_test\Controller\BatchTestController::testThemeBatch'
+  requirements:
+    _access: 'TRUE'
+
+batch_test.test_title:
+  path: '/batch-test/test-title'
+  defaults:
+    _controller: '\Drupal\batch_test\Controller\BatchTestController::testTitleBatch'
+  requirements:
+    _access: 'TRUE'

core/modules/system/tests/modules/batch_test/src/Controller/BatchTestController.php

@@ -0,0 +1,134 @@
+<?php
+/**
+ * @file
+ * Contains \Drupal\batch_test\Controller\BatchTestController.
+ */
+
+namespace Drupal\batch_test\Controller;
+
+use Drupal\Core\Form\FormState;
+
+/**
+ * Controller routines for batch tests.
+ */
+class BatchTestController {
+
+  /**
+   * Redirects successfully.
+   *
+   * @return array
+   *   Render array containing success message.
+   */
+  public function testRedirect() {
+    return array(
+      'success' => array(
+        '#markup' => 'Redirection successful.',
+      )
+    );
+  }
+
+  /**
+   * Fires a batch process without a form submission.
+   *
+   * @return \Symfony\Component\HttpFoundation\RedirectResponse|null
+   *   A redirect response if the batch is progressive. No return value otherwise.
+   */
+  public function testLargePercentage() {
+    batch_test_stack(NULL, TRUE);
+
+    batch_set(_batch_test_batch_5());
+    return batch_process('batch-test/redirect');
+  }
+
+  /**
+   * Submits a form within a batch programmatically.
+   *
+   * @param int $value
+   *   Some value passed to a custom batch callback.
+   *
+   * @return \Symfony\Component\HttpFoundation\RedirectResponse|null
+   *   A redirect response if the batch is progressive. No return value otherwise.
+   */
+  public function testNestedDrupalFormSubmit($value = 1) {
+    // Set the batch and process it.
+    $batch['operations'] = array(
+      array('_batch_test_nested_drupal_form_submit_callback', array($value)),
+    );
+    batch_set($batch);
+    return batch_process('batch-test/redirect');
+  }
+
+  /**
+   * Fires a batch process without a form submission.
+   *
+   * @return \Symfony\Component\HttpFoundation\RedirectResponse|null
+   *   A redirect response if the batch is progressive. No return value otherwise.
+   */
+  public function testNoForm() {
+    batch_test_stack(NULL, TRUE);
+
+    batch_set(_batch_test_batch_1());
+    return batch_process('batch-test/redirect');
+
+  }
+
+  /**
+   * Submits the 'Chained' form programmatically.
+   *
+   * Programmatic form: the page submits the 'Chained' form through
+   * \Drupal::formBuilder()->submitForm().
+   *
+   * @param int $value
+   *   Some value passed to a the chained form.
+   *
+   * @return array
+   *   Render array containing markup.
+   */
+  function testProgrammatic($value = 1) {
+    $form_state = (new FormState())->setValues([
+      'value' => $value,
+    ]);
+    \Drupal::formBuilder()->submitForm('Drupal\batch_test\Form\BatchTestChainedForm', $form_state);
+    return array(
+      'success' => array(
+        '#markup' => 'Got out of a programmatic batched form.',
+      )
+    );
+  }
+
+  /**
+   * Runs a batch for testing theme used on the progress page.
+   *
+   * @return \Symfony\Component\HttpFoundation\RedirectResponse|null
+   *   A redirect response if the batch is progressive. No return value otherwise.
+   */
+  public function testThemeBatch() {
+    batch_test_stack(NULL, TRUE);
+    $batch = array(
+      'operations' => array(
+        array('_batch_test_theme_callback', array()),
+      ),
+    );
+    batch_set($batch);
+    return batch_process('batch-test/redirect');
+  }
+
+  /**
+   * Runs a batch for testing the title shown on the progress page.
+   *
+   * @return \Symfony\Component\HttpFoundation\RedirectResponse|null
+   *   A redirect response if the batch is progressive. No return value otherwise.
+   */
+  public function testTitleBatch() {
+    batch_test_stack(NULL, TRUE);
+    $batch = [
+      'title' => 'Batch Test',
+      'operations' => [
+        ['_batch_test_title_callback', []],
+      ],
+    ];
+    batch_set($batch);
+    return batch_process('batch-test/redirect');
+  }
+
+}

core/modules/system/tests/modules/batch_test/src/Form/BatchTestChainedForm.php

@@ -0,0 +1,112 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\batch_test\Form\BatchTestChainedForm.
+ */
+
+namespace Drupal\batch_test\Form;
+
+use Drupal\Core\Form\FormBase;
+use Drupal\Core\Form\FormStateInterface;
+
+/**
+ * Generate form of id batch_test_chained_form.
+ */
+class BatchTestChainedForm extends FormBase {
+
+  /**
+   * {@inheritdoc}
+   */
+  public function getFormId() {
+    return 'batch_test_chained_form';
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function buildForm(array $form, FormStateInterface $form_state) {
+    // This value is used to test that $form_state persists through batched
+    // submit handlers.
+    $form['value'] = array(
+      '#type' => 'textfield',
+      '#title' => 'Value',
+      '#default_value' => 1,
+    );
+    $form['submit'] = array(
+      '#type' => 'submit',
+      '#value' => 'Submit',
+    );
+    $form['#submit'] = array(
+      'Drupal\batch_test\Form\BatchTestChainedForm::batchTestChainedFormSubmit1',
+      'Drupal\batch_test\Form\BatchTestChainedForm::batchTestChainedFormSubmit2',
+      'Drupal\batch_test\Form\BatchTestChainedForm::batchTestChainedFormSubmit3',
+      'Drupal\batch_test\Form\BatchTestChainedForm::batchTestChainedFormSubmit4',
+    );
+    return $form;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function submitForm(array &$form, FormStateInterface $form_state) {
+  }
+
+  /**
+   * Form submission handler #1 for batch_test_chained_form
+   */
+  public static function batchTestChainedFormSubmit1($form, FormStateInterface $form_state) {
+    batch_test_stack(NULL, TRUE);
+
+    batch_test_stack('submit handler 1');
+    batch_test_stack('value = ' . $form_state->getValue('value'));
+
+    $value = &$form_state->getValue('value');
+    $value++;
+    batch_set(_batch_test_batch_1());
+
+    $form_state->setRedirect('batch_test.redirect');
+  }
+
+  /**
+   * Form submission handler #2 for batch_test_chained_form
+   */
+  public static function batchTestChainedFormSubmit2($form, FormStateInterface $form_state) {
+    batch_test_stack('submit handler 2');
+    batch_test_stack('value = ' . $form_state->getValue('value'));
+
+    $value = &$form_state->getValue('value');
+    $value++;
+    batch_set(_batch_test_batch_2());
+
+    $form_state->setRedirect('batch_test.redirect');
+  }
+
+  /**
+   * Form submission handler #3 for batch_test_chained_form
+   */
+  public static function batchTestChainedFormSubmit3($form, FormStateInterface $form_state) {
+    batch_test_stack('submit handler 3');
+    batch_test_stack('value = ' . $form_state->getValue('value'));
+
+    $value = &$form_state->getValue('value');
+    $value++;
+
+    $form_state->setRedirect('batch_test.redirect');
+  }
+
+  /**
+   * Form submission handler #4 for batch_test_chained_form
+   */
+  public static function batchTestChainedFormSubmit4($form, FormStateInterface $form_state) {
+    batch_test_stack('submit handler 4');
+    batch_test_stack('value = ' . $form_state->getValue('value'));
+
+    $value = &$form_state->getValue('value');
+    $value++;
+    batch_set(_batch_test_batch_3());
+
+    $form_state->setRedirect('batch_test.redirect');
+  }
+
+}

core/modules/system/tests/modules/batch_test/src/Form/BatchTestMockForm.php

@@ -0,0 +1,48 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\batch_test\Form\BatchTestMockForm.
+ */
+
+namespace Drupal\batch_test\Form;
+
+use Drupal\Core\Form\FormBase;
+use Drupal\Core\Form\FormStateInterface;
+
+/**
+ * Generate form of id batch_test_mock_form.
+ */
+class BatchTestMockForm extends FormBase {
+
+  /**
+   * {@inheritdoc}
+   */
+  public function getFormId() {
+    return 'batch_test_mock_form';
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function buildForm(array $form, FormStateInterface $form_state) {
+    $form['test_value'] = array(
+      '#title' => t('Test value'),
+      '#type' => 'textfield',
+    );
+    $form['submit'] = array(
+      '#type' => 'submit',
+      '#value' => t('Submit'),
+    );
+
+    return $form;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function submitForm(array &$form, FormStateInterface $form_state) {
+    batch_test_stack('mock form submitted with value = ' . $form_state->getValue('test_value'));
+  }
+
+}

core/modules/system/tests/modules/batch_test/src/Form/BatchTestMultiStepForm.php

@@ -0,0 +1,70 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\batch_test\Form\BatchTestMultiStepForm.
+ */
+
+namespace Drupal\batch_test\Form;
+
+use Drupal\Core\Form\FormBase;
+use Drupal\Core\Form\FormStateInterface;
+
+/**
+ * Generate form of id batch_test_multistep_form.
+ */
+class BatchTestMultiStepForm extends FormBase {
+
+  /**
+   * {@inheritdoc}
+   */
+  public function getFormId() {
+    return 'batch_test_multistep_form';
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function buildForm(array $form, FormStateInterface $form_state) {
+    $step = $form_state->get('step');
+    if (empty($step)) {
+      $step = 1;
+      $form_state->set('step', $step);
+    }
+
+    $form['step_display'] = array(
+      '#markup' => 'step ' . $step . '<br/>',
+    );
+    $form['submit'] = array(
+      '#type' => 'submit',
+      '#value' => 'Submit',
+    );
+
+    return $form;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function submitForm(array &$form, FormStateInterface $form_state) {
+    batch_test_stack(NULL, TRUE);
+
+    $step = $form_state->get('step');
+    switch ($step) {
+      case 1:
+        batch_set(_batch_test_batch_1());
+        break;
+      case 2:
+        batch_set(_batch_test_batch_2());
+        break;
+    }
+
+    if ($step < 2) {
+      $form_state->set('step', ++$step);
+      $form_state->setRebuild();
+    }
+
+    $form_state->setRedirect('batch_test.redirect');
+  }
+
+}

core/modules/system/tests/modules/batch_test/src/Form/BatchTestSimpleForm.php

@@ -0,0 +1,60 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\batch_test\Form\BatchTestSimpleForm.
+ */
+
+namespace Drupal\batch_test\Form;
+
+use Drupal\Core\Form\FormBase;
+use Drupal\Core\Form\FormStateInterface;
+
+/**
+ * Generate form of id batch_test_simple_form.
+ */
+class BatchTestSimpleForm extends FormBase {
+
+  /**
+   * {@inheritdoc}
+   */
+  public function getFormId() {
+    return 'batch_test_simple_form';
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function buildForm(array $form, FormStateInterface $form_state) {
+    $form['batch'] = array(
+      '#type' => 'select',
+      '#title' => 'Choose batch',
+      '#options' => array(
+        'batch_0' => 'batch 0',
+        'batch_1' => 'batch 1',
+        'batch_2' => 'batch 2',
+        'batch_3' => 'batch 3',
+        'batch_4' => 'batch 4',
+      ),
+    );
+    $form['submit'] = array(
+      '#type' => 'submit',
+      '#value' => 'Submit',
+    );
+
+    return $form;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function submitForm(array &$form, FormStateInterface $form_state) {
+    batch_test_stack(NULL, TRUE);
+
+    $function = '_batch_test_' . $form_state->getValue('batch');
+    batch_set($function());
+
+    $form_state->setRedirect('batch_test.redirect');
+  }
+
+}

core/modules/system/tests/modules/cache_test/cache_test.info.yml

@@ -0,0 +1,6 @@
+name: 'Cache test'
+type: module
+description: 'Support module for cache system testing.'
+package: Testing
+version: VERSION
+core: 8.x

core/modules/system/tests/modules/common_test/common_test.css

@@ -0,0 +1,2 @@
+
+/* This file is for testing CSS file inclusion, no contents are necessary. */

core/modules/system/tests/modules/common_test/common_test.info.yml

@@ -0,0 +1,6 @@
+name: 'Common Test'
+type: module
+description: 'Support module for Common tests.'
+package: Testing
+version: VERSION
+core: 8.x

core/modules/system/tests/modules/common_test/common_test.libraries.yml

@@ -0,0 +1,115 @@
+jquery.farbtastic:
+  version: 0.1
+  js:
+    assets/vendor/farbtastic/farbtastic.js: {}
+  css:
+    component:
+      assets/vendor/farbtastic/farbtastic.css: {}
+  dependencies:
+    - core/jquery
+
+# Library to test CSS and JS file assets.
+files:
+  js:
+    foo.js: {}
+  css:
+    theme:
+      bar.css: {}
+
+# Library to test external CSS and JS file assets.
+external:
+  version: 1
+  js:
+    http://example.com/script.js: { type: external }
+  css:
+    theme:
+      http://example.com/stylesheet.css: { type: external }
+
+# Library to test JS file asset attributes (both internal and external).
+js-attributes:
+  version: 1
+  js:
+    deferred-internal.js: { attributes: { defer: true, bar: foo } }
+    http://example.com/deferred-external.js:
+      type: external
+      attributes:
+        foo: bar
+        defer: true
+
+js-header:
+  header: true
+  js:
+    header.js: {}
+  dependencies:
+    - core/drupal
+
+# Library to test setting cache = FALSE, to prevent aggregation.
+no-cache:
+  js:
+    nocache.js: { cache: false }
+
+order:
+  js:
+    weight_-3_1.js: { weight: -3 }
+    weight_0_1.js: {}
+    weight_0_2.js: {}
+    weight_-8_1.js: { weight: -8 }
+    weight_-8_2.js: { weight: -8 }
+    weight_-8_3.js: { weight: -8 }
+    http://example.com/weight_-5_1.js: { type: external, weight: -5 }
+    weight_-8_4.js: { weight: -8 }
+    weight_-3_2.js: { weight: -3 }
+    weight_0_3.js: {}
+  css:
+    base:
+      base_weight_0_1.js: {}
+      base_weight_0_2.js: {}
+      base_weight_-8_1.js: { weight: -8 }
+      base_weight_-101_1.js: { weight: -101 }
+    layout:
+      layout_weight_0_1.js: {}
+      layout_weight_0_2.js: {}
+      layout_weight_-8_1.js: { weight: -8 }
+      layout_weight_-101_1.js: { weight: -101 }
+    component:
+      component_weight_0_1.js: {}
+      component_weight_0_2.js: {}
+      component_weight_-8_1.js: { weight: -8}
+      component_weight_-101_1.js: { weight: -101}
+    state:
+      state_weight_0_1.js: {}
+      state_weight_0_2.js: {}
+      state_weight_-8_1.js: { weight: -8}
+      state_weight_-101_1.js: { weight: -101}
+    theme:
+      theme_weight_0_1.js: {}
+      theme_weight_0_2.js: {}
+      theme_weight_-8_1.js: { weight: -8}
+      theme_weight_-101_1.js: { weight: -101}
+
+weight:
+  css:
+    theme:
+      first.css: {}
+      lighter.js: { weight: -1 }
+  js:
+    first.js: {}
+    lighter.js: { weight: -1 }
+    before-jquery.js: { weight: -21 }
+
+browsers:
+  js:
+    old-ie.js:
+      browsers:
+        'IE': 'lte IE 8'
+        '!IE': false
+    no-ie.js:
+      browsers:
+        IE: false
+
+querystring:
+  js:
+    querystring.js?arg1=value1&arg2=value2: {}
+  css:
+    theme:
+      querystring.css?arg1=value1&arg2=value2: {}

core/modules/system/tests/modules/common_test/common_test.module

@@ -0,0 +1,280 @@
+<?php
+
+/**
+ * @file
+ * Helper module for the Common tests.
+ */
+
+use \Drupal\Core\Asset\AttachedAssetsInterface;
+
+/**
+ * Applies #printed to an element to help test #pre_render.
+ */
+function common_test_drupal_render_printing_pre_render($elements) {
+  $elements['#printed'] = TRUE;
+  return $elements;
+}
+
+/**
+ * Implements hook_TYPE_alter().
+ */
+function common_test_drupal_alter_alter(&$data, &$arg2 = NULL, &$arg3 = NULL) {
+  // Alter first argument.
+  if (is_array($data)) {
+    $data['foo'] = 'Drupal';
+  }
+  elseif (is_object($data)) {
+    $data->foo = 'Drupal';
+  }
+  // Alter second argument, if present.
+  if (isset($arg2)) {
+    if (is_array($arg2)) {
+      $arg2['foo'] = 'Drupal';
+    }
+    elseif (is_object($arg2)) {
+      $arg2->foo = 'Drupal';
+    }
+  }
+  // Try to alter third argument, if present.
+  if (isset($arg3)) {
+    if (is_array($arg3)) {
+      $arg3['foo'] = 'Drupal';
+    }
+    elseif (is_object($arg3)) {
+      $arg3->foo = 'Drupal';
+    }
+  }
+}
+
+/**
+ * Implements hook_TYPE_alter() on behalf of Bartik theme.
+ *
+ * Same as common_test_drupal_alter_alter(), but here, we verify that themes
+ * can also alter and come last.
+ */
+function bartik_drupal_alter_alter(&$data, &$arg2 = NULL, &$arg3 = NULL) {
+  // Alter first argument.
+  if (is_array($data)) {
+    $data['foo'] .= ' theme';
+  }
+  elseif (is_object($data)) {
+    $data->foo .= ' theme';
+  }
+  // Alter second argument, if present.
+  if (isset($arg2)) {
+    if (is_array($arg2)) {
+      $arg2['foo'] .= ' theme';
+    }
+    elseif (is_object($arg2)) {
+      $arg2->foo .= ' theme';
+    }
+  }
+  // Try to alter third argument, if present.
+  if (isset($arg3)) {
+    if (is_array($arg3)) {
+      $arg3['foo'] .= ' theme';
+    }
+    elseif (is_object($arg3)) {
+      $arg3->foo .= ' theme';
+    }
+  }
+}
+
+/**
+ * Implements hook_TYPE_alter() on behalf of block module.
+ *
+ * This is to verify that
+ * \Drupal::moduleHandler()->alter(array(TYPE1, TYPE2), ...) allows
+ * hook_module_implements_alter() to affect the order in which module
+ * implementations are executed.
+ */
+function block_drupal_alter_foo_alter(&$data, &$arg2 = NULL, &$arg3 = NULL) {
+  $data['foo'] .= ' block';
+}
+
+/**
+ * Implements hook_module_implements_alter().
+ *
+ * @see block_drupal_alter_foo_alter()
+ */
+function common_test_module_implements_alter(&$implementations, $hook) {
+  // For
+  // \Drupal::moduleHandler()->alter(array('drupal_alter', 'drupal_alter_foo'), ...),
+  // make the block module implementations run after all the other modules. Note
+  // that when \Drupal::moduleHandler->alter() is called with an array of types,
+  // the first type is considered primary and controls the module order.
+  if ($hook == 'drupal_alter_alter' && isset($implementations['block'])) {
+    $group = $implementations['block'];
+    unset($implementations['block']);
+    $implementations['block'] = $group;
+  }
+}
+
+/**
+ * Implements hook_theme().
+ */
+function common_test_theme() {
+  return array(
+    'common_test_foo' => array(
+      'variables' => array('foo' => 'foo', 'bar' => 'bar'),
+    ),
+    'common_test_render_element' => array(
+      'render element' => 'foo',
+    ),
+    'common_test_empty' => array(
+      'variables' => array('foo' => 'foo'),
+      'function' => 'theme_common_test_empty',
+    ),
+  );
+}
+
+/**
+ * Provides a theme function for drupal_render().
+ */
+function theme_common_test_foo($variables) {
+  return $variables['foo'] . $variables['bar'];
+}
+
+/**
+ * Always returns an empty string.
+ */
+function theme_common_test_empty($variables) {
+  return '';
+}
+
+/**
+ * Implements MODULE_preprocess().
+ *
+ * @see RenderTest::testDrupalRenderThemePreprocessAttached()
+ */
+function common_test_preprocess(&$variables, $hook) {
+  if (!\Drupal::state()->get('theme_preprocess_attached_test', FALSE)) {
+    return;
+  }
+  $variables['#attached']['library'][] = 'test/generic_preprocess';
+}
+
+/**
+ * Implements MODULE_preprocess_HOOK().
+ *
+ * @see RenderTest::testDrupalRenderThemePreprocessAttached()
+ */
+function common_test_preprocess_common_test_render_element(&$variables) {
+  if (!\Drupal::state()->get('theme_preprocess_attached_test', FALSE)) {
+    return;
+  }
+  $variables['#attached']['library'][] = 'test/specific_preprocess';
+}
+
+/**
+ * Implements hook_library_info_build().
+ */
+function common_test_library_info_build() {
+  $libraries = [];
+  if (\Drupal::state()->get('common_test.library_info_build_test')) {
+    $libraries['dynamic_library'] = [
+      'version' => '1.0',
+      'css' => [
+        'base' => [
+          'common_test.css' => [],
+        ],
+      ],
+    ];
+  }
+  return $libraries;
+}
+
+/**
+ * Implements hook_library_info_alter().
+ */
+function common_test_library_info_alter(&$libraries, $module) {
+  if ($module == 'core' && isset($libraries['jquery.farbtastic'])) {
+    // Change the version of Farbtastic to 0.0.
+    $libraries['jquery.farbtastic']['version'] = '0.0';
+    // Make Farbtastic depend on jQuery Form to test library dependencies.
+    $libraries['jquery.farbtastic']['dependencies'][] = 'core/jquery.form';
+  }
+
+  // Alter the dynamically registered library definition.
+  if ($module == 'common_test' && isset($libraries['dynamic_library'])) {
+    $libraries['dynamic_library']['dependencies'] = [
+      'core/jquery',
+    ];
+  }
+}
+
+/**
+ * Implements hook_cron().
+ *
+ * System module should handle if a module does not catch an exception and keep
+ * cron going.
+ *
+ * @see common_test_cron_helper()
+ *
+ */
+function common_test_cron() {
+  throw new Exception(t('Uncaught exception'));
+}
+
+/**
+ * Implements hook_page_attachments().
+ *
+ * @see \Drupal\system\Tests\Common\PageRenderTest::assertPageRenderHookExceptions()
+ */
+function common_test_page_attachments(array &$page) {
+  $page['#attached']['library'][] = 'core/foo';
+  $page['#attached']['library'][] = 'core/bar';
+  $page['#cache']['tags'] = ['example'];
+  $page['#cache']['contexts'] = ['user.permissions'];
+
+  if (\Drupal::state()->get('common_test.hook_page_attachments.descendant_attached', FALSE)) {
+    $page['content']['#attached']['library'][] = 'core/jquery';
+  }
+
+  if (\Drupal::state()->get('common_test.hook_page_attachments.render_array', FALSE)) {
+    $page['something'] = [
+      '#markup' => 'test',
+    ];
+  }
+}
+
+/**
+ * Implements hook_page_attachments_alter().
+ *
+ * @see \Drupal\system\Tests\Common\PageRenderTest::assertPageRenderHookExceptions()
+ */
+function common_test_page_attachments_alter(array &$page) {
+  // Remove a library that was added in common_test_page_attachments(), to test
+  // that this hook can do what it claims to do.
+  if (isset($page['#attached']['library']) && ($index = array_search('core/bar', $page['#attached']['library'])) && $index !== FALSE) {
+    unset($page['#attached']['library'][$index]);
+  }
+  $page['#attached']['library'][] = 'core/baz';
+  $page['#cache']['tags'] = ['example'];
+  $page['#cache']['contexts'] = ['user.permissions'];
+
+  if (\Drupal::state()->get('common_test.hook_page_attachments_alter.descendant_attached', FALSE)) {
+    $page['content']['#attached']['library'][] = 'core/jquery';
+  }
+
+  if (\Drupal::state()->get('common_test.hook_page_attachments_alter.render_array', FALSE)) {
+    $page['something'] = [
+      '#markup' => 'test',
+    ];
+  }
+}
+
+/**
+ * Implements hook_js_settings_alter().
+ *
+ * @see \Drupal\system\Tests\Common\JavaScriptTest::testHeaderSetting()
+ */
+function common_test_js_settings_alter(&$settings, AttachedAssetsInterface $assets) {
+  // Modify an existing setting.
+  if (array_key_exists('pluralDelimiter', $settings)) {
+    $settings['pluralDelimiter'] = '☃';
+  }
+
+  // Add a setting.
+  $settings['foo'] = 'bar';
+}

core/modules/system/tests/modules/common_test/common_test.print.css

@@ -0,0 +1,2 @@
+
+/* This file is for testing CSS file inclusion, no contents are necessary. */

core/modules/system/tests/modules/common_test/common_test.routing.yml

@@ -0,0 +1,21 @@
+common_test.l_active_class:
+  path: '/common-test/type-link-active-class'
+  defaults:
+    _controller: '\Drupal\common_test\Controller\CommonTestController::typeLinkActiveClass'
+  requirements:
+    _access: 'TRUE'
+
+common_test.destination:
+  path: '/common-test/destination'
+  defaults:
+    _controller: '\Drupal\common_test\Controller\CommonTestController::destination'
+  requirements:
+    _access: 'TRUE'
+
+common_test.js_and_css_querystring:
+  path: '/common-test/query-string'
+  defaults:
+    _title: 'Test querystring'
+    _controller: '\Drupal\common_test\Controller\CommonTestController::jsAndCssQuerystring'
+  requirements:
+    _access: 'TRUE'

core/modules/system/tests/modules/common_test/src/Controller/CommonTestController.php

@@ -0,0 +1,96 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\common_test\Controller\CommonTestController.
+ */
+
+namespace Drupal\common_test\Controller;
+
+use Drupal\Component\Utility\SafeMarkup;
+use Drupal\Core\Url;
+use Symfony\Component\HttpFoundation\Response;
+
+/**
+ * Controller routines for common_test routes.
+ */
+class CommonTestController {
+
+  /**
+   * Returns links to the current page, with and without query strings.
+   *
+   * Using #type 'link' causes these links to be rendered with _l().
+   */
+  public function typeLinkActiveClass() {
+    return array(
+      'no_query' => array(
+        '#type' => 'link',
+        '#title' => t('Link with no query string'),
+        '#url' => Url::fromRoute('<current>'),
+        '#options' => array(
+          'set_active_class' => TRUE,
+        ),
+      ),
+      'with_query' => array(
+        '#type' => 'link',
+        '#title' => t('Link with a query string'),
+        '#url' => Url::fromRoute('<current>'),
+        '#options' => array(
+          'query' => array(
+            'foo' => 'bar',
+            'one' => 'two',
+          ),
+          'set_active_class' => TRUE,
+        ),
+      ),
+      'with_query_reversed' => array(
+        '#type' => 'link',
+        '#title' => t('Link with the same query string in reverse order'),
+        '#url' => Url::fromRoute('<current>'),
+        '#options' => array(
+          'query' => array(
+            'one' => 'two',
+            'foo' => 'bar',
+          ),
+          'set_active_class' => TRUE,
+        ),
+      ),
+    );
+  }
+
+  /**
+   * Adds a JavaScript file and a CSS file with a query string appended.
+   *
+   * @return string
+   *   An empty string.
+   */
+  public function jsAndCssQuerystring() {
+    $attached = array(
+      '#attached' => array(
+        'library' => array(
+          'node/drupal.node',
+        ),
+        'css' => array(
+          drupal_get_path('module', 'node') . '/css/node.admin.css' => array(),
+          // A relative URI may have a query string.
+          '/' . drupal_get_path('module', 'node') . '/node-fake.css?arg1=value1&arg2=value2' => array(),
+        ),
+      ),
+    );
+    return \Drupal::service('renderer')->renderRoot($attached);
+  }
+
+  /**
+   * Prints a destination query parameter.
+   *
+   * @return \Symfony\Component\HttpFoundation\Response
+   *   A new Response object containing a string with the destination query
+   *   parameter.
+   */
+  public function destination() {
+    $destination = \Drupal::destination()->getAsArray();
+    $output = "The destination: " . SafeMarkup::checkPlain($destination['destination']);
+    return new Response($output);
+  }
+
+}

core/modules/system/tests/modules/common_test/templates/common-test-foo.html.twig

@@ -0,0 +1,13 @@
+{#
+/**
+ * @file
+ * Default theme implementation for the common test foo.
+ *
+ * Available variables:
+ * - foo: foo.
+ * - bar: bar.
+ *
+ * @ingroup themeable
+ */
+#}
+{{ foo }}{{ bar -}}

core/modules/system/tests/modules/common_test/templates/common-test-render-element.html.twig

@@ -0,0 +1,12 @@
+{#
+/**
+ * @file
+ * Default theme implementation for the common test render element.
+ *
+ * Available variables:
+ * - foo: A render array.
+ *
+ * @ingroup themeable
+ */
+#}
+{{ foo }}

core/modules/system/tests/modules/common_test_cron_helper/common_test_cron_helper.info.yml

@@ -0,0 +1,6 @@
+name: 'Common Test Cron Helper'
+type: module
+description: 'Helper module for CronRunTestCase::testCronExceptions().'
+package: Testing
+version: VERSION
+core: 8.x

core/modules/system/tests/modules/common_test_cron_helper/common_test_cron_helper.module

@@ -0,0 +1,18 @@
+<?php
+
+/**
+ * @file
+ * Helper module for the testCronExceptions in addition to common_test module.
+ */
+
+/**
+ * Implements hook_cron().
+ *
+ * common_test_cron() throws an exception, but the execution should reach this
+ * function as well.
+ *
+ * @see common_test_cron()
+ */
+function common_test_cron_helper_cron() {
+  \Drupal::state()->set('common_test.cron', 'success');
+}

core/modules/system/tests/modules/condition_test/condition_test.info.yml

@@ -0,0 +1,6 @@
+name: "Condition Test Support"
+type: module
+description: "Test general form component for condition plugins."
+package: Testing
+version: VERSION
+core: 8.x

core/modules/system/tests/modules/condition_test/condition_test.routing.yml

@@ -0,0 +1,6 @@
+condition_test.1:
+  path: '/condition_test'
+  defaults:
+    _form: '\Drupal\condition_test\FormController'
+  requirements:
+    _access: 'TRUE'

core/modules/system/tests/modules/condition_test/src/FormController.php

@@ -0,0 +1,78 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\condition_test\FormController.
+ */
+
+namespace Drupal\condition_test;
+
+use Drupal\Core\Form\FormInterface;
+use Drupal\Core\Condition\ConditionManager;
+use Drupal\Core\Form\FormStateInterface;
+use Drupal\node\Entity\Node;
+
+/**
+ * Routing controller class for condition_test testing of condition forms.
+ */
+class FormController implements FormInterface {
+
+  /**
+   * The condition plugin we will be working with.
+   *
+   * @var \Drupal\Core\Condition\ConditionInterface
+   */
+  protected $condition;
+
+  /**
+   * {@inheritdoc}
+   */
+  public function getFormId() {
+    return 'condition_node_type_test_form';
+  }
+
+  /**
+   * Constructs a \Drupal\condition_test\FormController object.
+   */
+  public function __construct() {
+    $manager = new ConditionManager(\Drupal::service('container.namespaces'), \Drupal::cache('discovery'), \Drupal::moduleHandler());
+    $this->condition = $manager->createInstance('node_type');
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function buildForm(array $form, FormStateInterface $form_state) {
+    $form = $this->condition->buildConfigurationForm($form, $form_state);
+    $form['actions']['submit'] = array(
+      '#type' => 'submit',
+      '#value' => t('Submit'),
+    );
+    return $form;
+  }
+
+  /**
+   * Implements \Drupal\Core\Form\FormInterface::validateForm().
+   *
+   */
+  public function validateForm(array &$form, FormStateInterface $form_state) {
+    $this->condition->validateConfigurationForm($form, $form_state);
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function submitForm(array &$form, FormStateInterface $form_state) {
+    $this->condition->submitConfigurationForm($form, $form_state);
+    $config = $this->condition->getConfig();
+    foreach ($config['bundles'] as $bundle) {
+      drupal_set_message('Bundle: ' . $bundle);
+    }
+
+    $article = Node::load(1);
+    $this->condition->setContextValue('node', $article);
+    if ($this->condition->execute()) {
+      drupal_set_message(t('Executed successfully.'));
+    }
+  }
+}

core/modules/system/tests/modules/condition_test/src/Plugin/Condition/ConditionTestDualUser.php

@@ -0,0 +1,42 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\condition_test\Plugin\Condition\ConditionTestDualUser.
+ */
+
+namespace Drupal\condition_test\Plugin\Condition;
+
+use Drupal\Core\Condition\ConditionPluginBase;
+
+/**
+ * Provides a condition that requires two users.
+ *
+ * @Condition(
+ *   id = "condition_test_dual_user",
+ *   label = @Translation("Dual user"),
+ *   context = {
+ *     "user1" = @ContextDefinition("entity:user", label = @Translation("User 1")),
+ *     "user2" = @ContextDefinition("entity:user", label = @Translation("User 2"))
+ *   }
+ * )
+ */
+class ConditionTestDualUser extends ConditionPluginBase {
+
+  /**
+   * {@inheritdoc}
+   */
+  public function evaluate() {
+    $user1 = $this->getContextValue('user1');
+    $user2 = $this->getContextValue('user2');
+    return $user1->id() === $user2->id();
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function summary() {
+    return $this->t('This condition has two users.');
+  }
+
+}

core/modules/system/tests/modules/condition_test/src/Tests/ConditionTestDualUserTest.php

@@ -0,0 +1,98 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\condition_test\Tests\ConditionTestDualUserTest.
+ */
+
+namespace Drupal\condition_test\Tests;
+
+use Drupal\Core\Plugin\Context\Context;
+use Drupal\Core\Plugin\Context\ContextDefinition;
+use Drupal\simpletest\KernelTestBase;
+use Drupal\user\Entity\User;
+
+/**
+ * Tests a condition that requires two users.
+ *
+ * @group condition_test
+ */
+class ConditionTestDualUserTest extends KernelTestBase {
+
+  /**
+   * An anonymous user for testing purposes.
+   *
+   * @var \Drupal\user\Entity\User
+   */
+  protected $anonymous;
+
+  /**
+   * An authenticated user for testing purposes.
+   *
+   * @var \Drupal\user\Entity\User
+   */
+  protected $authenticated;
+
+  /**
+   * {@inheritdoc}
+   */
+  public static $modules = ['system', 'user', 'condition_test'];
+
+  /**
+   * {@inheritdoc}
+   */
+  protected function setUp() {
+    parent::setUp();
+
+    $this->installSchema('system', 'sequences');
+    $this->installEntitySchema('user');
+
+    $this->anonymous = User::create(['uid' => 0]);
+    $this->authenticated = User::create(['uid' => 1]);
+  }
+
+  /**
+   * Tests the dual user condition.
+   */
+  public function testConditions() {
+    $this->doTestIdenticalUser();
+    $this->doTestDifferentUser();
+  }
+
+  /**
+   * Tests with both contexts mapped to the same user.
+   */
+  protected function doTestIdenticalUser() {
+    /** @var \Drupal\Core\Condition\ConditionPluginBase $condition */
+    $condition = \Drupal::service('plugin.manager.condition')
+      ->createInstance('condition_test_dual_user')
+      // Map the anonymous user to both contexts.
+      ->setContextMapping([
+        'user1' => 'anonymous',
+        'user2' => 'anonymous',
+      ]);
+    $definition = new ContextDefinition('entity:user');
+    $contexts['anonymous'] = (new Context($definition))->setContextValue($this->anonymous);
+    \Drupal::service('context.handler')->applyContextMapping($condition, $contexts);
+    $this->assertTrue($condition->execute());
+  }
+
+  /**
+   * Tests with each context mapped to different users.
+   */
+  protected function doTestDifferentUser() {
+    /** @var \Drupal\Core\Condition\ConditionPluginBase $condition */
+    $condition = \Drupal::service('plugin.manager.condition')
+      ->createInstance('condition_test_dual_user')
+      ->setContextMapping([
+        'user1' => 'anonymous',
+        'user2' => 'authenticated',
+      ]);
+    $definition = new ContextDefinition('entity:user');
+    $contexts['anonymous'] = (new Context($definition))->setContextValue($this->anonymous);
+    $contexts['authenticated'] = (new Context($definition))->setContextValue($this->authenticated);
+    \Drupal::service('context.handler')->applyContextMapping($condition, $contexts);
+    $this->assertFalse($condition->execute());
+  }
+
+}

core/modules/system/tests/modules/conneg_test/conneg_test.info.yml

@@ -0,0 +1,6 @@
+name: Content negotiation test
+type: module
+description: 'Support testing content negotiation variations.'
+package: Core
+version: VERSION
+core: 8.x

core/modules/system/tests/modules/conneg_test/conneg_test.routing.yml

@@ -0,0 +1,32 @@
+# Tests
+conneg.simpletest:
+  path: conneg/simple.json
+  defaults:
+    _controller: '\Drupal\conneg_test\Controller\TestController::simple'
+  requirements:
+    _access: 'TRUE'
+conneg.html:
+  path: conneg/html
+  defaults:
+    _controller: '\Drupal\conneg_test\Controller\TestController::html'
+  requirements:
+    _access: 'TRUE'
+conneg.simple_conneg:
+  path: conneg/html
+  defaults:
+    _controller: '\Drupal\conneg_test\Controller\TestController::format'
+  requirements:
+    _access: 'TRUE'
+    _format: 'json|xml'
+conneg.variable_with_period:
+  path: conneg/plugin/{plugin_id}
+  defaults:
+    _controller: '\Drupal\conneg_test\Controller\TestController::variable'
+  requirements:
+    _access: 'TRUE'
+conneg.full_content_negotiation:
+  path: conneg/negotiate
+  defaults:
+    _controller: '\Drupal\conneg_test\Controller\TestController::format'
+  requirements:
+    _access: 'TRUE'

core/modules/system/tests/modules/conneg_test/src/Controller/TestController.php

@@ -0,0 +1,76 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\conneg_test\Controller\TestController.
+ */
+
+namespace Drupal\conneg_test\Controller;
+
+use Symfony\Component\HttpFoundation\JsonResponse;
+use Symfony\Component\HttpFoundation\Request;
+use Symfony\Component\HttpFoundation\Response;
+
+/**
+ * Test controller for content negotation tests.
+ */
+class TestController {
+
+  /**
+   * Returns a json response.
+   *
+   * @return \Symfony\Component\HttpFoundation\JsonResponse
+   */
+  public function simple() {
+    return new JsonResponse(['some' => 'data']);
+  }
+
+  /**
+   * Returns a simple render array.
+   *
+   * @return array
+   */
+  public function html() {
+    return [
+      '#markup' => 'here',
+    ];
+  }
+
+  /**
+   * Returns different responses dependening on the request format.
+   *
+   * @param \Symfony\Component\HttpFoundation\Request $request
+   *   The request
+   *
+   * @return \Symfony\Component\HttpFoundation\Response
+   *   The response.
+   */
+  public function format(Request $request) {
+    switch ($request->getRequestFormat()) {
+      case 'json':
+        return new JsonResponse(['some' => 'data']);
+
+      case 'xml':
+        return new Response('<xml></xml>', Response::HTTP_OK, ['Content-Type' => 'application/xml']);
+
+      default:
+        return new Response($request->getRequestFormat());
+    }
+  }
+
+  /**
+   * Returns a render array depending on some passed in value.
+   *
+   * @param string $plugin_id
+   *   The plugin ID.
+   *
+   * @return array
+   *   The render array
+   */
+  public function variable($plugin_id) {
+    return [
+      '#markup' => $plugin_id,
+    ];
+  }
+
+}

core/modules/system/tests/modules/cron_queue_test/cron_queue_test.info.yml

@@ -0,0 +1,6 @@
+name: 'Cron Queue test'
+type: module
+description: 'Support module for the cron queue runner.'
+package: Testing
+version: VERSION
+core: 8.x

core/modules/system/tests/modules/cron_queue_test/src/Plugin/QueueWorker/CronQueueTestBrokenQueue.php

@@ -0,0 +1,32 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\cron_queue_test\Plugin\QueueWorker\CronQueueTestBrokenQueue.
+ */
+
+namespace Drupal\cron_queue_test\Plugin\QueueWorker;
+
+use Drupal\Core\Queue\QueueWorkerBase;
+use Drupal\Core\Queue\SuspendQueueException;
+
+/**
+ * @QueueWorker(
+ *   id = "cron_queue_test_broken_queue",
+ *   title = @Translation("Broken queue test"),
+ *   cron = {"time" = 60}
+ * )
+ */
+class CronQueueTestBrokenQueue extends QueueWorkerBase {
+
+  /**
+   * {@inheritdoc}
+   */
+  public function processItem($data) {
+    if ($data == 'crash') {
+      throw new SuspendQueueException('The queue is broken.');
+    }
+    // Do nothing otherwise.
+  }
+
+}

core/modules/system/tests/modules/cron_queue_test/src/Plugin/QueueWorker/CronQueueTestException.php

@@ -0,0 +1,28 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\cron_queue_test\Plugin\QueueWorker\CronQueueTestException.
+ */
+
+namespace Drupal\cron_queue_test\Plugin\QueueWorker;
+
+use Drupal\Core\Queue\QueueWorkerBase;
+
+/**
+ * @QueueWorker(
+ *   id = "cron_queue_test_exception",
+ *   title = @Translation("Exception test"),
+ *   cron = {"time" = 60}
+ * )
+ */
+class CronQueueTestException extends QueueWorkerBase {
+
+  /**
+   * {@inheritdoc}
+   */
+  public function processItem($data) {
+    throw new \Exception('That is not supposed to happen.');
+  }
+
+}

core/modules/system/tests/modules/database_test/database_test.info.yml

@@ -0,0 +1,6 @@
+name: 'Database Test'
+type: module
+description: 'Support module for Database layer tests.'
+core: 8.x
+package: Testing
+version: VERSION

core/modules/system/tests/modules/database_test/database_test.install

@@ -0,0 +1,278 @@
+<?php
+
+/**
+ * @file
+ * Install, update and uninstall functions for the database_test module.
+ */
+
+/**
+ * Implements hook_schema().
+ *
+ * The database tests use the database API which depends on schema
+ * information for certain operations on certain databases.
+ * Therefore, the schema must actually be declared in a normal module
+ * like any other, not directly in the test file.
+ */
+function database_test_schema() {
+  $schema['test'] = array(
+    'description' => 'Basic test table for the database unit tests.',
+    'fields' => array(
+      'id' => array(
+        'type' => 'serial',
+        'unsigned' => TRUE,
+        'not null' => TRUE,
+      ),
+      'name' => array(
+        'description' => "A person's name",
+        'type' => 'varchar_ascii',
+        'length' => 255,
+        'not null' => TRUE,
+        'default' => '',
+        'binary' => TRUE,
+      ),
+      'age' => array(
+        'description' => "The person's age",
+        'type' => 'int',
+        'unsigned' => TRUE,
+        'not null' => TRUE,
+        'default' => 0,
+      ),
+      'job' => array(
+        'description' => "The person's job",
+        'type' => 'varchar',
+        'length' => 255,
+        'not null' => TRUE,
+        'default' => 'Undefined',
+      ),
+    ),
+    'primary key' => array('id'),
+    'unique keys' => array(
+      'name' => array('name')
+    ),
+    'indexes' => array(
+      'ages' => array('age'),
+    ),
+  );
+
+  // This is an alternate version of the same table that is structured the same
+  // but has a non-serial Primary Key.
+  $schema['test_people'] = array(
+    'description' => 'A duplicate version of the test table, used for additional tests.',
+    'fields' => array(
+      'name' => array(
+        'description' => "A person's name",
+        'type' => 'varchar',
+        'length' => 255,
+        'not null' => TRUE,
+        'default' => '',
+      ),
+      'age' => array(
+        'description' => "The person's age",
+        'type' => 'int',
+        'unsigned' => TRUE,
+        'not null' => TRUE,
+        'default' => 0,
+      ),
+      'job' => array(
+        'description' => "The person's job",
+        'type' => 'varchar_ascii',
+        'length' => 255,
+        'not null' => TRUE,
+        'default' => '',
+      ),
+    ),
+    'primary key' => array('job'),
+    'indexes' => array(
+      'ages' => array('age'),
+    ),
+  );
+
+  $schema['test_people_copy'] = array(
+    'description' => 'A duplicate version of the test_people table, used for additional tests.',
+    'fields' => array(
+      'name' => array(
+        'description' => "A person's name",
+        'type' => 'varchar',
+        'length' => 255,
+        'not null' => TRUE,
+        'default' => '',
+      ),
+      'age' => array(
+        'description' => "The person's age",
+        'type' => 'int',
+        'unsigned' => TRUE,
+        'not null' => TRUE,
+        'default' => 0,
+      ),
+      'job' => array(
+        'description' => "The person's job",
+        'type' => 'varchar_ascii',
+        'length' => 255,
+        'not null' => TRUE,
+        'default' => '',
+      ),
+    ),
+    'primary key' => array('job'),
+    'indexes' => array(
+      'ages' => array('age'),
+    ),
+  );
+
+  $schema['test_one_blob'] = array(
+    'description' => 'A simple table including a BLOB field for testing BLOB behavior.',
+    'fields' => array(
+      'id' => array(
+        'description' => 'Simple unique ID.',
+        'type' => 'serial',
+        'not null' => TRUE,
+      ),
+      'blob1' => array(
+        'description' => 'A BLOB field.',
+        'type' => 'blob',
+      ),
+    ),
+    'primary key' => array('id'),
+    );
+
+  $schema['test_two_blobs'] = array(
+    'description' => 'A simple test table with two BLOB fields.',
+    'fields' => array(
+      'id' => array(
+        'description' => 'Simple unique ID.',
+        'type' => 'serial',
+        'not null' => TRUE,
+      ),
+      'blob1' => array(
+        'description' => 'A dummy BLOB field.',
+        'type' => 'blob',
+      ),
+      'blob2' => array(
+        'description' => 'A second BLOB field.',
+        'type' => 'blob'
+      ),
+    ),
+    'primary key' => array('id'),
+    );
+
+  $schema['test_task'] = array(
+    'description' => 'A task list for people in the test table.',
+    'fields' => array(
+      'tid' => array(
+        'description' => 'Task ID, primary key.',
+        'type' => 'serial',
+        'not null' => TRUE,
+      ),
+      'pid' => array(
+        'description' => 'The {test_people}.pid, foreign key for the test table.',
+        'type' => 'int',
+        'unsigned' => TRUE,
+        'not null' => TRUE,
+        'default' => 0,
+      ),
+      'task' => array(
+        'description' => 'The task to be completed.',
+        'type' => 'varchar',
+        'length' => 255,
+        'not null' => TRUE,
+        'default' => '',
+      ),
+      'priority' => array(
+        'description' => 'The priority of the task.',
+        'type' => 'int',
+        'unsigned' => TRUE,
+        'not null' => TRUE,
+        'default' => 0,
+      ),
+    ),
+    'primary key' => array('tid'),
+  );
+
+  $schema['test_null'] = array(
+    'description' => 'Basic test table for NULL value handling.',
+    'fields' => array(
+      'id' => array(
+        'type' => 'serial',
+        'unsigned' => TRUE,
+        'not null' => TRUE,
+      ),
+      'name' => array(
+        'description' => "A person's name.",
+        'type' => 'varchar_ascii',
+        'length' => 255,
+        'not null' => FALSE,
+        'default' => '',
+      ),
+      'age' => array(
+        'description' => "The person's age.",
+        'type' => 'int',
+        'unsigned' => TRUE,
+        'not null' => FALSE,
+        'default' => 0),
+    ),
+    'primary key' => array('id'),
+    'unique keys' => array(
+      'name' => array('name')
+    ),
+    'indexes' => array(
+      'ages' => array('age'),
+    ),
+  );
+
+  $schema['test_serialized'] = array(
+    'description' => 'Basic test table for NULL value handling.',
+    'fields' => array(
+      'id' => array(
+        'type' => 'serial',
+        'unsigned' => TRUE,
+        'not null' => TRUE,
+      ),
+      'name' => array(
+        'description' => "A person's name.",
+        'type' => 'varchar_ascii',
+        'length' => 255,
+        'not null' => FALSE,
+        'default' => '',
+      ),
+      'info' => array(
+        'description' => "The person's data in serialized form.",
+        'type' => 'blob',
+        'serialize' => TRUE,
+      ),
+    ),
+    'primary key' => array('id'),
+    'unique keys' => array(
+      'name' => array('name')
+    ),
+  );
+
+  $schema['test_composite_primary'] = array(
+    'description' => 'Basic test table with a composite primary key',
+    'fields' => array(
+      'name' => array(
+        'description' => "A person's name",
+        'type' => 'varchar',
+        'length' => 50,
+        'not null' => TRUE,
+        'default' => '',
+        'binary' => TRUE,
+      ),
+      'age' => array(
+        'description' => "The person's age",
+        'type' => 'int',
+        'unsigned' => TRUE,
+        'not null' => TRUE,
+        'default' => 0,
+      ),
+      'job' => array(
+        'description' => "The person's job",
+        'type' => 'varchar',
+        'length' => 255,
+        'not null' => TRUE,
+        'default' => 'Undefined',
+      ),
+    ),
+    'primary key' => array('name', 'age'),
+  );
+
+  return $schema;
+}

core/modules/system/tests/modules/database_test/database_test.module

@@ -0,0 +1,46 @@
+<?php
+
+use Drupal\Core\Database\Query\AlterableInterface;
+use Symfony\Component\HttpFoundation\JsonResponse;
+
+/**
+ * Implements hook_query_alter().
+ */
+function database_test_query_alter(AlterableInterface $query) {
+
+  if ($query->hasTag('database_test_alter_add_range')) {
+    $query->range(0, 2);
+  }
+
+  if ($query->hasTag('database_test_alter_add_join')) {
+    $people_alias = $query->join('test', 'people', "test_task.pid = %alias.id");
+    $query->addField($people_alias, 'name', 'name');
+    $query->condition($people_alias . '.id', 2);
+  }
+
+  if ($query->hasTag('database_test_alter_change_conditional')) {
+    $conditions =& $query->conditions();
+    $conditions[0]['value'] = 2;
+  }
+
+  if ($query->hasTag('database_test_alter_change_fields')) {
+    $fields =& $query->getFields();
+    unset($fields['age']);
+  }
+
+  if ($query->hasTag('database_test_alter_change_expressions')) {
+    $expressions =& $query->getExpressions();
+    $expressions['double_age']['expression'] = 'age*3';
+  }
+}
+
+
+/**
+ * Implements hook_query_TAG_alter().
+ *
+ * Called by DatabaseTestCase::testAlterRemoveRange.
+ */
+function database_test_query_database_test_alter_remove_range_alter(AlterableInterface $query) {
+  $query->range();
+}
+

core/modules/system/tests/modules/database_test/database_test.routing.yml

@@ -0,0 +1,41 @@
+database_test.db_query_temporary:
+  path: '/database_test/db_query_temporary'
+  defaults:
+    _controller: '\Drupal\database_test\Controller\DatabaseTestController::dbQueryTemporary'
+  requirements:
+    _access: 'TRUE'
+
+database_test.pager_query_even:
+  path: '/database_test/pager_query_even/{limit}'
+  defaults:
+    _controller: '\Drupal\database_test\Controller\DatabaseTestController::pagerQueryEven'
+  requirements:
+    _access: 'TRUE'
+
+database_test.pager_query_odd:
+  path: '/database_test/pager_query_odd/{limit}'
+  defaults:
+    _controller: '\Drupal\database_test\Controller\DatabaseTestController::pagerQueryOdd'
+  requirements:
+    _access: 'TRUE'
+
+database_test.tablesort:
+  path: '/database_test/tablesort'
+  defaults:
+    _controller: '\Drupal\database_test\Controller\DatabaseTestController::testTablesort'
+  requirements:
+    _access: 'TRUE'
+
+database_test.tablesort_first:
+  path: '/database_test/tablesort_first'
+  defaults:
+    _controller: '\Drupal\database_test\Controller\DatabaseTestController::testTablesortFirst'
+  requirements:
+    _access: 'TRUE'
+
+database_test.tablesort_default_sort:
+  path: '/database_test/tablesort_default_sort'
+  defaults:
+    _form: '\Drupal\database_test\Form\DatabaseTestForm'
+  requirements:
+    _access: 'TRUE'

core/modules/system/tests/modules/database_test/src/Controller/DatabaseTestController.php

@@ -0,0 +1,150 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\database_test\Controller\DatabaseTestController.
+ */
+
+namespace Drupal\database_test\Controller;
+
+use Symfony\Component\HttpFoundation\JsonResponse;
+
+/**
+ * Controller routines for database_test routes.
+ */
+class DatabaseTestController {
+
+  /**
+   * Runs db_query_temporary() and outputs the table name and its number of rows.
+   *
+   * We need to test that the table created is temporary, so we run it here, in a
+   * separate menu callback request; After this request is done, the temporary
+   * table should automatically dropped.
+   *
+   * @return \Symfony\Component\HttpFoundation\JsonResponse
+   */
+  public function dbQueryTemporary() {
+    $table_name = db_query_temporary('SELECT age FROM {test}', array());
+    return new JsonResponse(array(
+      'table_name' => $table_name,
+      'row_count' => db_select($table_name)->countQuery()->execute()->fetchField(),
+    ));
+  }
+
+  /**
+   * Runs a pager query and returns the results.
+   *
+   * This function does care about the page GET parameter, as set by the
+   * simpletest HTTP call.
+   *
+   * @return \Symfony\Component\HttpFoundation\JsonResponse
+   */
+  public function pagerQueryEven($limit) {
+    $query = db_select('test', 't');
+    $query
+      ->fields('t', array('name'))
+      ->orderBy('age');
+
+    // This should result in 2 pages of results.
+    $query = $query
+      ->extend('Drupal\Core\Database\Query\PagerSelectExtender')
+      ->limit($limit);
+
+    $names = $query->execute()->fetchCol();
+
+    return new JsonResponse(array(
+      'names' => $names,
+    ));
+  }
+
+  /**
+   * Runs a pager query and returns the results.
+   *
+   * This function does care about the page GET parameter, as set by the
+   * simpletest HTTP call.
+   *
+   * @return \Symfony\Component\HttpFoundation\JsonResponse
+   */
+  public function pagerQueryOdd($limit) {
+    $query = db_select('test_task', 't');
+    $query
+      ->fields('t', array('task'))
+      ->orderBy('pid');
+
+    // This should result in 4 pages of results.
+    $query = $query
+      ->extend('Drupal\Core\Database\Query\PagerSelectExtender')
+      ->limit($limit);
+
+    $names = $query->execute()->fetchCol();
+
+    return new JsonResponse(array(
+      'names' => $names,
+    ));
+  }
+
+  /**
+   * Runs a tablesort query and returns the results.
+   *
+   * This function does care about the page GET parameter, as set by the
+   * simpletest HTTP call.
+   *
+   * @return \Symfony\Component\HttpFoundation\JsonResponse
+   */
+  public function testTablesort() {
+    $header = array(
+      'tid' => array('data' => t('Task ID'), 'field' => 'tid', 'sort' => 'desc'),
+      'pid' => array('data' => t('Person ID'), 'field' => 'pid'),
+      'task' => array('data' => t('Task'), 'field' => 'task'),
+      'priority' => array('data' => t('Priority'), 'field' => 'priority', ),
+    );
+
+    $query = db_select('test_task', 't');
+    $query
+      ->fields('t', array('tid', 'pid', 'task', 'priority'));
+
+    $query = $query
+      ->extend('Drupal\Core\Database\Query\TableSortExtender')
+      ->orderByHeader($header);
+
+    // We need all the results at once to check the sort.
+    $tasks = $query->execute()->fetchAll();
+
+    return new JsonResponse(array(
+      'tasks' => $tasks,
+    ));
+  }
+
+  /**
+   * Runs a tablesort query with a second order_by after and returns the results.
+   *
+   * This function does care about the page GET parameter, as set by the
+   * simpletest HTTP call.
+   *
+   * @return \Symfony\Component\HttpFoundation\JsonResponse
+   */
+  public function testTablesortFirst() {
+    $header = array(
+      'tid' => array('data' => t('Task ID'), 'field' => 'tid', 'sort' => 'desc'),
+      'pid' => array('data' => t('Person ID'), 'field' => 'pid'),
+      'task' => array('data' => t('Task'), 'field' => 'task'),
+      'priority' => array('data' => t('Priority'), 'field' => 'priority', ),
+    );
+
+    $query = db_select('test_task', 't');
+    $query
+      ->fields('t', array('tid', 'pid', 'task', 'priority'));
+
+    $query = $query
+      ->extend('Drupal\Core\Database\Query\TableSortExtender')
+      ->orderByHeader($header)
+      ->orderBy('priority');
+
+    // We need all the results at once to check the sort.
+    $tasks = $query->execute()->fetchAll();
+
+    return new JsonResponse(array(
+      'tasks' => $tasks,
+    ));
+  }
+}

core/modules/system/tests/modules/database_test/src/Form/DatabaseTestForm.php

@@ -0,0 +1,81 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\database_test\Form\DatabaseTestForm.
+ */
+
+namespace Drupal\database_test\Form;
+
+use Drupal\Component\Utility\SafeMarkup;
+use Drupal\Core\Form\FormBase;
+use Drupal\Core\Form\FormStateInterface;
+use Drupal\user\Entity\User;
+
+/**
+ * Form controller for database_test module.
+ */
+class DatabaseTestForm extends FormBase {
+
+  /**
+   * {@inheritdoc}
+   */
+  public function getFormId() {
+    return 'database_test_theme_tablesort';
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function buildForm(array $form, FormStateInterface $form_state) {
+    $header = array(
+      'username' => array('data' => t('Username'), 'field' => 'u.name'),
+      'status' => array('data' => t('Status'), 'field' => 'u.status'),
+    );
+
+    $query = db_select('users_field_data', 'u');
+    $query->condition('u.uid', 0, '<>');
+    $query->condition('u.default_langcode', 1);
+
+    $count_query = clone $query;
+    $count_query->addExpression('COUNT(u.uid)');
+
+    $query = $query
+      ->extend('Drupal\Core\Database\Query\PagerSelectExtender')
+      ->extend('Drupal\Core\Database\Query\TableSortExtender');
+    $query
+      ->fields('u', array('uid'))
+      ->limit(50)
+      ->orderByHeader($header)
+      ->setCountQuery($count_query);
+    $uids = $query
+      ->execute()
+      ->fetchCol();
+
+    $options = array();
+
+    foreach (User::loadMultiple($uids) as $account) {
+      $options[$account->id()] = array(
+        'title' => array('data' => array('#title' => SafeMarkup::checkPlain($account->getUsername()))),
+        'username' => SafeMarkup::checkPlain($account->getUsername()),
+        'status' =>  $account->isActive() ? t('active') : t('blocked'),
+      );
+    }
+
+    $form['accounts'] = array(
+      '#type' => 'tableselect',
+      '#header' => $header,
+      '#options' => $options,
+      '#empty' => t('No people available.'),
+    );
+
+    return $form;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function submitForm(array &$form, FormStateInterface $form_state) {
+  }
+
+}

core/modules/system/tests/modules/drupal_system_listing_compatible_test/drupal_system_listing_compatible_test.info.yml

@@ -0,0 +1,6 @@
+name: 'Drupal system listing compatible test'
+type: module
+description: 'Support module for testing the drupal_system_listing function.'
+package: Testing
+version: VERSION
+core: 8.x

core/modules/system/tests/modules/entity_crud_hook_test/entity_crud_hook_test.info.yml

@@ -0,0 +1,6 @@
+name: 'Entity CRUD Hooks Test'
+type: module
+description: 'Support module for CRUD hook tests.'
+core: 8.x
+package: Testing
+version: VERSION

core/modules/system/tests/modules/entity_crud_hook_test/entity_crud_hook_test.module

@@ -0,0 +1,400 @@
+<?php
+
+/**
+ * @file
+ * Test module for the Entity CRUD API.
+ */
+
+use Drupal\Core\Entity\EntityInterface;
+
+/**
+ * Implements hook_entity_create().
+ */
+function entity_crud_hook_test_entity_create(EntityInterface $entity) {
+  $GLOBALS['entity_crud_hook_test'][] = (__FUNCTION__ . ' called for type ' . $entity->getEntityTypeId());
+}
+
+/**
+ * Implements hook_ENTITY_TYPE_create() for block entities.
+ */
+function entity_crud_hook_test_block_create() {
+  $GLOBALS['entity_crud_hook_test'][] = (__FUNCTION__ . ' called');
+}
+
+/**
+ * Implements hook_ENTITY_TYPE_create() for comment entities.
+ */
+function entity_crud_hook_test_comment_create() {
+  $GLOBALS['entity_crud_hook_test'][] = (__FUNCTION__ . ' called');
+}
+
+/**
+ * Implements hook_ENTITY_TYPE_create() for file entities.
+ */
+function entity_crud_hook_test_file_create() {
+  $GLOBALS['entity_crud_hook_test'][] = (__FUNCTION__ . ' called');
+}
+
+/**
+ * Implements hook_ENTITY_TYPE_create() for node entities.
+ */
+function entity_crud_hook_test_node_create() {
+  $GLOBALS['entity_crud_hook_test'][] = (__FUNCTION__ . ' called');
+}
+
+/**
+ * Implements hook_ENTITY_TYPE_create() for taxonomy_term entities.
+ */
+function entity_crud_hook_test_taxonomy_term_create() {
+  $GLOBALS['entity_crud_hook_test'][] = (__FUNCTION__ . ' called');
+}
+
+/**
+ * Implements hook_ENTITY_TYPE_create() for taxonomy_vocabulary entities.
+ */
+function entity_crud_hook_test_taxonomy_vocabulary_create() {
+  $GLOBALS['entity_crud_hook_test'][] = (__FUNCTION__ . ' called');
+}
+
+/**
+ * Implements hook_ENTITY_TYPE_create() for user entities.
+ */
+function entity_crud_hook_test_user_create() {
+  $GLOBALS['entity_crud_hook_test'][] = (__FUNCTION__ . ' called');
+}
+
+/**
+ * Implements hook_entity_presave().
+ */
+function entity_crud_hook_test_entity_presave(EntityInterface $entity) {
+  $GLOBALS['entity_crud_hook_test'][] = (__FUNCTION__ . ' called for type ' . $entity->getEntityTypeId());
+}
+
+/**
+ * Implements hook_ENTITY_TYPE_presave() for block entities.
+ */
+function entity_crud_hook_test_block_presave() {
+  $GLOBALS['entity_crud_hook_test'][] = (__FUNCTION__ . ' called');
+}
+
+/**
+ * Implements hook_ENTITY_TYPE_presave() for comment entities.
+ */
+function entity_crud_hook_test_comment_presave() {
+  $GLOBALS['entity_crud_hook_test'][] = (__FUNCTION__ . ' called');
+}
+
+/**
+ * Implements hook_ENTITY_TYPE_presave() for file entities.
+ */
+function entity_crud_hook_test_file_presave() {
+  $GLOBALS['entity_crud_hook_test'][] = (__FUNCTION__ . ' called');
+}
+
+/**
+ * Implements hook_ENTITY_TYPE_presave() for node entities.
+ */
+function entity_crud_hook_test_node_presave() {
+  $GLOBALS['entity_crud_hook_test'][] = (__FUNCTION__ . ' called');
+}
+
+/**
+ * Implements hook_ENTITY_TYPE_presave() for taxonomy_term entities.
+ */
+function entity_crud_hook_test_taxonomy_term_presave() {
+  $GLOBALS['entity_crud_hook_test'][] = (__FUNCTION__ . ' called');
+}
+
+/**
+ * Implements hook_ENTITY_TYPE_presave() for taxonomy_vocabulary entities.
+ */
+function entity_crud_hook_test_taxonomy_vocabulary_presave() {
+  $GLOBALS['entity_crud_hook_test'][] = (__FUNCTION__ . ' called');
+}
+
+/**
+ * Implements hook_ENTITY_TYPE_presave() for user entities.
+ */
+function entity_crud_hook_test_user_presave() {
+  $GLOBALS['entity_crud_hook_test'][] = (__FUNCTION__ . ' called');
+}
+
+/**
+ * Implements hook_entity_insert().
+ */
+function entity_crud_hook_test_entity_insert(EntityInterface $entity) {
+  $GLOBALS['entity_crud_hook_test'][] = (__FUNCTION__ . ' called for type ' . $entity->getEntityTypeId());
+}
+
+/**
+ * Implements hook_ENTITY_TYPE_insert() for block entities.
+ */
+function entity_crud_hook_test_block_insert() {
+  $GLOBALS['entity_crud_hook_test'][] = (__FUNCTION__ . ' called');
+}
+
+/**
+ * Implements hook_ENTITY_TYPE_insert() for comment entities.
+ */
+function entity_crud_hook_test_comment_insert() {
+  $GLOBALS['entity_crud_hook_test'][] = (__FUNCTION__ . ' called');
+}
+
+/**
+ * Implements hook_ENTITY_TYPE_insert() for file entities.
+ */
+function entity_crud_hook_test_file_insert() {
+  $GLOBALS['entity_crud_hook_test'][] = (__FUNCTION__ . ' called');
+}
+
+/**
+ * Implements hook_ENTITY_TYPE_insert() for node entities.
+ */
+function entity_crud_hook_test_node_insert() {
+  $GLOBALS['entity_crud_hook_test'][] = (__FUNCTION__ . ' called');
+}
+
+/**
+ * Implements hook_ENTITY_TYPE_insert() for taxonomy_term entities.
+ */
+function entity_crud_hook_test_taxonomy_term_insert() {
+  $GLOBALS['entity_crud_hook_test'][] = (__FUNCTION__ . ' called');
+}
+
+/**
+ * Implements hook_ENTITY_TYPE_insert() for taxonomy_vocabulary entities.
+ */
+function entity_crud_hook_test_taxonomy_vocabulary_insert() {
+  $GLOBALS['entity_crud_hook_test'][] = (__FUNCTION__ . ' called');
+}
+
+/**
+ * Implements hook_ENTITY_TYPE_insert() for user entities.
+ */
+function entity_crud_hook_test_user_insert() {
+  $GLOBALS['entity_crud_hook_test'][] = (__FUNCTION__ . ' called');
+}
+
+/**
+ * Implements hook_entity_load().
+ */
+function entity_crud_hook_test_entity_load(array $entities, $type) {
+  $GLOBALS['entity_crud_hook_test'][] = (__FUNCTION__ . ' called for type ' . $type);
+}
+
+/**
+ * Implements hook_ENTITY_TYPE_load() for block entities.
+ */
+function entity_crud_hook_test_block_load() {
+  $GLOBALS['entity_crud_hook_test'][] = (__FUNCTION__ . ' called');
+}
+
+/**
+ * Implements hook_ENTITY_TYPE_load() for comment entities.
+ */
+function entity_crud_hook_test_comment_load() {
+  $GLOBALS['entity_crud_hook_test'][] = (__FUNCTION__ . ' called');
+}
+
+/**
+ * Implements hook_ENTITY_TYPE_load() for file entities.
+ */
+function entity_crud_hook_test_file_load() {
+  $GLOBALS['entity_crud_hook_test'][] = (__FUNCTION__ . ' called');
+}
+
+/**
+ * Implements hook_ENTITY_TYPE_load() for node entities.
+ */
+function entity_crud_hook_test_node_load() {
+  $GLOBALS['entity_crud_hook_test'][] = (__FUNCTION__ . ' called');
+}
+
+/**
+ * Implements hook_ENTITY_TYPE_load() for taxonomy_term entities.
+ */
+function entity_crud_hook_test_taxonomy_term_load() {
+  $GLOBALS['entity_crud_hook_test'][] = (__FUNCTION__ . ' called');
+}
+
+/**
+ * Implements hook_ENTITY_TYPE_load() for taxonomy_vocabulary entities.
+ */
+function entity_crud_hook_test_taxonomy_vocabulary_load() {
+  $GLOBALS['entity_crud_hook_test'][] = (__FUNCTION__ . ' called');
+}
+
+/**
+ * Implements hook_ENTITY_TYPE_load() for user entities.
+ */
+function entity_crud_hook_test_user_load() {
+  $GLOBALS['entity_crud_hook_test'][] = (__FUNCTION__ . ' called');
+}
+
+/**
+ * Implements hook_entity_update().
+ */
+function entity_crud_hook_test_entity_update(EntityInterface $entity) {
+  $GLOBALS['entity_crud_hook_test'][] = (__FUNCTION__ . ' called for type ' . $entity->getEntityTypeId());
+}
+
+/**
+ * Implements hook_ENTITY_TYPE_update() for block entities.
+ */
+function entity_crud_hook_test_block_update() {
+  $GLOBALS['entity_crud_hook_test'][] = (__FUNCTION__ . ' called');
+}
+
+/**
+ * Implements hook_ENTITY_TYPE_update() for comment entities.
+ */
+function entity_crud_hook_test_comment_update() {
+  $GLOBALS['entity_crud_hook_test'][] = (__FUNCTION__ . ' called');
+}
+
+/**
+ * Implements hook_ENTITY_TYPE_update() for file entities.
+ */
+function entity_crud_hook_test_file_update() {
+  $GLOBALS['entity_crud_hook_test'][] = (__FUNCTION__ . ' called');
+}
+
+/**
+ * Implements hook_ENTITY_TYPE_update() for node entities.
+ */
+function entity_crud_hook_test_node_update() {
+  $GLOBALS['entity_crud_hook_test'][] = (__FUNCTION__ . ' called');
+}
+
+/**
+ * Implements hook_ENTITY_TYPE_update() for taxonomy_term entities.
+ */
+function entity_crud_hook_test_taxonomy_term_update() {
+  $GLOBALS['entity_crud_hook_test'][] = (__FUNCTION__ . ' called');
+}
+
+/**
+ * Implements hook_ENTITY_TYPE_update() for taxonomy_vocabulary entities.
+ */
+function entity_crud_hook_test_taxonomy_vocabulary_update() {
+  $GLOBALS['entity_crud_hook_test'][] = (__FUNCTION__ . ' called');
+}
+
+/**
+ * Implements hook_ENTITY_TYPE_update() for user entities.
+ */
+function entity_crud_hook_test_user_update() {
+  $GLOBALS['entity_crud_hook_test'][] = (__FUNCTION__ . ' called');
+}
+
+/**
+ * Implements hook_entity_predelete().
+ */
+function entity_crud_hook_test_entity_predelete(EntityInterface $entity) {
+  $GLOBALS['entity_crud_hook_test'][] = (__FUNCTION__ . ' called for type ' . $entity->getEntityTypeId());
+}
+
+/**
+ * Implements hook_ENTITY_TYPE_predelete() for block entities.
+ */
+function entity_crud_hook_test_block_predelete() {
+  $GLOBALS['entity_crud_hook_test'][] = (__FUNCTION__ . ' called');
+}
+
+/**
+ * Implements hook_ENTITY_TYPE_predelete() for comment entities.
+ */
+function entity_crud_hook_test_comment_predelete() {
+  $GLOBALS['entity_crud_hook_test'][] = (__FUNCTION__ . ' called');
+}
+
+/**
+ * Implements hook_ENTITY_TYPE_predelete() for file entities.
+ */
+function entity_crud_hook_test_file_predelete() {
+  $GLOBALS['entity_crud_hook_test'][] = (__FUNCTION__ . ' called');
+}
+
+/**
+ * Implements hook_ENTITY_TYPE_predelete() for node entities.
+ */
+function entity_crud_hook_test_node_predelete() {
+  $GLOBALS['entity_crud_hook_test'][] = (__FUNCTION__ . ' called');
+}
+
+/**
+ * Implements hook_ENTITY_TYPE_predelete() for taxonomy_term entities.
+ */
+function entity_crud_hook_test_taxonomy_term_predelete() {
+  $GLOBALS['entity_crud_hook_test'][] = (__FUNCTION__ . ' called');
+}
+
+/**
+ * Implements hook_ENTITY_TYPE_predelete() for taxonomy_vocabulary entities.
+ */
+function entity_crud_hook_test_taxonomy_vocabulary_predelete() {
+  $GLOBALS['entity_crud_hook_test'][] = (__FUNCTION__ . ' called');
+}
+
+/**
+ * Implements hook_ENTITY_TYPE_predelete() for user entities.
+ */
+function entity_crud_hook_test_user_predelete() {
+  $GLOBALS['entity_crud_hook_test'][] = (__FUNCTION__ . ' called');
+}
+
+/**
+ * Implements hook_entity_delete().
+ */
+function entity_crud_hook_test_entity_delete(EntityInterface $entity) {
+  $GLOBALS['entity_crud_hook_test'][] = (__FUNCTION__ . ' called for type ' . $entity->getEntityTypeId());
+}
+
+/**
+ * Implements hook_ENTITY_TYPE_delete() for block entities.
+ */
+function entity_crud_hook_test_block_delete() {
+  $GLOBALS['entity_crud_hook_test'][] = (__FUNCTION__ . ' called');
+}
+
+/**
+ * Implements hook_ENTITY_TYPE_delete() for comment entities.
+ */
+function entity_crud_hook_test_comment_delete() {
+  $GLOBALS['entity_crud_hook_test'][] = (__FUNCTION__ . ' called');
+}
+
+/**
+ * Implements hook_ENTITY_TYPE_delete() for file entities.
+ */
+function entity_crud_hook_test_file_delete() {
+  $GLOBALS['entity_crud_hook_test'][] = (__FUNCTION__ . ' called');
+}
+
+/**
+ * Implements hook_ENTITY_TYPE_delete() for node entities.
+ */
+function entity_crud_hook_test_node_delete() {
+  $GLOBALS['entity_crud_hook_test'][] = (__FUNCTION__ . ' called');
+}
+
+/**
+ * Implements hook_ENTITY_TYPE_delete() for taxonomy_term entities.
+ */
+function entity_crud_hook_test_taxonomy_term_delete() {
+  $GLOBALS['entity_crud_hook_test'][] = (__FUNCTION__ . ' called');
+}
+
+/**
+ * Implements hook_ENTITY_TYPE_delete() for taxonomy_vocabulary entities.
+ */
+function entity_crud_hook_test_taxonomy_vocabulary_delete() {
+  $GLOBALS['entity_crud_hook_test'][] = (__FUNCTION__ . ' called');
+}
+
+/**
+ * Implements hook_ENTITY_TYPE_delete() for user entities.
+ */
+function entity_crud_hook_test_user_delete() {
+  $GLOBALS['entity_crud_hook_test'][] = (__FUNCTION__ . ' called');
+}

core/modules/system/tests/modules/entity_schema_test/entity_schema_test.info.yml

@@ -0,0 +1,8 @@
+name: 'Entity schema test module'
+type: module
+description: 'Provides entity and field definitions to test entity schema.'
+package: Testing
+version: VERSION
+core: 8.x
+dependencies:
+  - entity_test

core/modules/system/tests/modules/entity_schema_test/entity_schema_test.module

@@ -0,0 +1,98 @@
+<?php
+
+/**
+ * @file
+ * Test module for the entity API providing a bundle field.
+ */
+
+use Drupal\Core\Entity\EntityTypeInterface;
+use Drupal\Core\Field\BaseFieldDefinition;
+use Drupal\entity_test\FieldStorageDefinition;
+use Drupal\entity_test\Entity\EntityTestMulRev;
+
+/**
+ * Implements hook_entity_type_alter().
+ */
+function entity_schema_test_entity_type_alter(array &$entity_types) {
+  if (\Drupal::state()->get('entity_schema_update')) {
+    $entity_type = $entity_types['entity_test'];
+    $entity_type->set('translatable', TRUE);
+    $entity_type->set('data_table', 'entity_test_field_data');
+    $keys = $entity_type->getKeys();
+    $keys['revision'] = 'revision_id';
+    $entity_type->set('entity_keys', $keys);
+  }
+}
+
+/**
+ * Implements hook_entity_base_field_info().
+ */
+function entity_schema_test_entity_base_field_info(EntityTypeInterface $entity_type) {
+  if ($entity_type->id() == 'entity_test') {
+    $definitions['custom_base_field'] = BaseFieldDefinition::create('string')
+      ->setName('custom_base_field')
+      ->setLabel(t('A custom base field'));
+    if (\Drupal::state()->get('entity_schema_update')) {
+      $definitions += EntityTestMulRev::baseFieldDefinitions($entity_type);
+      // And add a revision log.
+      $definitions['revision_log'] = BaseFieldDefinition::create('string_long')
+        ->setLabel(t('Revision log message'))
+        ->setDescription(t('The log entry explaining the changes in this revision.'))
+        ->setRevisionable(TRUE);
+    }
+    return $definitions;
+  }
+}
+
+/**
+ * Implements hook_entity_field_storage_info().
+ */
+function entity_schema_test_entity_field_storage_info(EntityTypeInterface $entity_type) {
+  if ($entity_type->id() == 'entity_test') {
+    $definitions['custom_bundle_field'] = FieldStorageDefinition::create('string')
+      ->setName('custom_bundle_field')
+      ->setLabel(t('A custom bundle field'))
+      ->setTargetEntityTypeId($entity_type->id());
+    return $definitions;
+  }
+}
+
+/**
+ * Implements hook_entity_bundle_field_info().
+ */
+function entity_schema_test_entity_bundle_field_info(EntityTypeInterface $entity_type, $bundle) {
+  if ($entity_type->id() == 'entity_test' && $bundle == 'custom') {
+    $definitions['custom_bundle_field'] = \Drupal::entityManager()->getFieldStorageDefinitions($entity_type->id())['custom_bundle_field'];
+    return $definitions;
+  }
+}
+
+/**
+ * Implements hook_entity_bundle_create().
+ */
+function entity_schema_test_entity_bundle_create($entity_type_id, $bundle) {
+  if ($entity_type_id == 'entity_test' && $bundle == 'custom') {
+    $entity_type = \Drupal::entityManager()->getDefinition($entity_type_id);
+    $field_definitions = entity_schema_test_entity_bundle_field_info($entity_type, $bundle);
+    $field_definitions['custom_bundle_field']
+      ->setTargetEntityTypeId($entity_type_id)
+      ->setTargetBundle($bundle);
+    // Notify the entity storage that we just created a new field.
+    \Drupal::entityManager()->onFieldDefinitionCreate($field_definitions['custom_bundle_field']);
+  }
+}
+
+/**
+ * Implements hook_entity_bundle_delete().
+ */
+function entity_schema_test_entity_bundle_delete($entity_type_id, $bundle) {
+  if ($entity_type_id == 'entity_test' && $bundle == 'custom') {
+    $entity_type = \Drupal::entityManager()->getDefinition($entity_type_id);
+    $field_definitions = entity_schema_test_entity_bundle_field_info($entity_type, $bundle);
+    $field_definitions['custom_bundle_field']
+      ->setTargetEntityTypeId($entity_type_id)
+      ->setTargetBundle($bundle);
+    // Notify the entity storage that our field is gone.
+    \Drupal::entityManager()->onFieldDefinitionDelete($field_definitions['custom_bundle_field']);
+  }
+}

core/modules/system/tests/modules/entity_test/config/install/core.entity_view_mode.entity_test.full.yml

@@ -0,0 +1,8 @@
+id: entity_test.full
+label: Full
+status: false
+cache: true
+targetEntityType: entity_test
+dependencies:
+  module:
+    - entity_test

core/modules/system/tests/modules/entity_test/config/install/core.entity_view_mode.entity_test.test.yml

@@ -0,0 +1,8 @@
+id: entity_test.test
+label: Test
+status: false
+cache: false
+targetEntityType: entity_test
+dependencies:
+  module:
+    - entity_test

core/modules/system/tests/modules/entity_test/config/schema/entity_test.schema.yml

@@ -0,0 +1,15 @@
+core.entity_view_display.*.*.*.third_party.entity_test:
+  type: mapping
+  label: 'Schema for entity_test module additions to entity_view_display entity'
+  mapping:
+    foo:
+      type: string
+      label: 'Label for foo'
+
+field.storage_settings.shape:
+  type: mapping
+  label: 'Shape field storage settings'
+  mapping:
+    foreign_key_name:
+      type: string
+      label: 'Foreign key name'

core/modules/system/tests/modules/entity_test/entity_test.info.yml

@@ -0,0 +1,10 @@
+name: 'Entity CRUD test module'
+type: module
+description: 'Provides entity types based upon the CRUD API.'
+package: Testing
+version: VERSION
+core: 8.x
+dependencies:
+  - field
+  - text
+  - entity_reference

core/modules/system/tests/modules/entity_test/entity_test.install

@@ -0,0 +1,51 @@
+<?php
+
+/**
+ * @file
+ * Install, update and uninstall functions for the entity_test module.
+ */
+
+/**
+ * Implements hook_install().
+ */
+function entity_test_install() {
+  foreach (entity_test_entity_types() as $entity_type) {
+    // Auto-create fields for testing.
+    entity_create('field_storage_config', array(
+      'entity_type' => $entity_type,
+      'field_name' => 'field_test_text',
+      'type' => 'text',
+      'cardinality' => 1,
+    ))->save();
+    entity_create('field_config', array(
+      'entity_type' => $entity_type,
+      'field_name' => 'field_test_text',
+      'bundle' => $entity_type,
+      'label' => 'Test text-field',
+      'translatable' => FALSE,
+    ))->save();
+
+    entity_get_form_display($entity_type, $entity_type, 'default')
+      ->setComponent('field_test_text', array('type' => 'text_textfield'))
+      ->save();
+  }
+}
+
+/**
+ * Implements hook_schema().
+ */
+function entity_test_schema() {
+  // Schema for simple entity.
+  $schema['entity_test_example'] = array(
+    'description' => 'Stores entity_test items.',
+    'fields' => array(
+      'id' => array(
+        'type' => 'serial',
+        'not null' => TRUE,
+        'description' => 'Primary Key: Unique entity-test item ID.',
+      ),
+    ),
+    'primary key' => array('id'),
+  );
+  return $schema;
+}

core/modules/system/tests/modules/entity_test/entity_test.links.task.yml

@@ -0,0 +1,2 @@
+entity_test.local_tasks:
+  deriver: 'Drupal\entity_test\Plugin\Derivative\EntityTestLocalTasks'

core/modules/system/tests/modules/entity_test/entity_test.module

@@ -0,0 +1,627 @@
+<?php
+
+/**
+ * @file
+ * Test module for the entity API providing several entity types for testing.
+ */
+
+use Drupal\Core\Access\AccessResult;
+use Drupal\Core\Entity\EntityInterface;
+use Drupal\Core\Entity\FieldableEntityInterface;
+use Drupal\Core\Entity\EntityTypeInterface;
+use Drupal\Core\Field\FieldDefinitionInterface;
+use Drupal\Core\Field\FieldItemListInterface;
+use Drupal\Core\Form\FormStateInterface;
+use Drupal\Core\Session\AccountInterface;
+use Drupal\Core\Entity\Entity\EntityFormDisplay;
+use Drupal\Core\Url;
+
+/**
+ * Filter that limits test entity list to revisable ones.
+ */
+const ENTITY_TEST_TYPES_REVISABLE = 1;
+
+/**
+ * Filter that limits test entity list to multilingual ones.
+ */
+const ENTITY_TEST_TYPES_MULTILINGUAL = 2;
+
+/**
+ * Filter that limits test entity list to routeable ones.
+ */
+const ENTITY_TEST_TYPES_ROUTING = 3;
+
+/**
+ * Returns a list of test entity types.
+ *
+ * The returned entity types are one for each available entity storage type:
+ * - The plain entity_test type supports neither revisions nor multilingual
+ *   properties.
+ * - The entity_test_mul type supports multilingual properties.
+ * - The entity_test_rev type supports revisions.
+ * - The entity_test_mulrev type supports both revisions and multilingual
+ *   properties.
+ *
+ * @param int $filter
+ *   Either ENTITY_TEST_TYPES_REVISABLE to only return revisable entity types or
+ *   ENTITY_TEST_TYPES_MULTILINGUAL to only return multilingual ones. Defaults
+ *   to NULL, which returns all.
+ *
+ * @return array
+ *   List with entity_types.
+ */
+function entity_test_entity_types($filter = NULL) {
+  $types = array();
+  if ($filter === NULL || $filter === ENTITY_TEST_TYPES_ROUTING) {
+    $types[] = 'entity_test';
+  }
+  if ($filter != ENTITY_TEST_TYPES_REVISABLE) {
+    $types[] = 'entity_test_mul';
+    $types[] = 'entity_test_mul_langcode_key';
+    $types[] = 'entity_test_mul_changed';
+  }
+  if ($filter != ENTITY_TEST_TYPES_MULTILINGUAL) {
+    $types[] = 'entity_test_rev';
+  }
+  if ($filter === ENTITY_TEST_TYPES_ROUTING) {
+    $types[] = 'entity_test_base_field_display';
+  }
+  $types[] = 'entity_test_mulrev';
+  $types[] = 'entity_test_mulrev_changed';
+
+  return array_combine($types, $types);
+}
+
+/**
+ * Implements hook_entity_type_alter().
+ */
+function entity_test_entity_type_alter(array &$entity_types) {
+  $state = \Drupal::state();
+
+  /** @var $entity_types \Drupal\Core\Entity\EntityTypeInterface[] */
+  foreach (entity_test_entity_types() as $entity_type) {
+    // Optionally specify a translation handler for testing translations.
+    if ($state->get('entity_test.translation')) {
+      $translation = $entity_types[$entity_type]->get('translation');
+      $translation[$entity_type] = TRUE;
+      $entity_types[$entity_type]->set('translation', $translation);
+    }
+  }
+
+  // Allow entity_test_update tests to override the entity type definition.
+  $entity_types['entity_test_update'] = $state->get('entity_test_update.entity_type', $entity_types['entity_test_update']);
+
+  // Enable the entity_test_new only when needed.
+  if (!$state->get('entity_test_new')) {
+    unset($entity_types['entity_test_new']);
+  }
+}
+
+/**
+ * Implements hook_entity_base_field_info_alter().
+ */
+function entity_test_entity_base_field_info_alter(&$fields, EntityTypeInterface $entity_type) {
+  if ($entity_type->id() == 'entity_test_mulrev' && ($names = \Drupal::state()->get('entity_test.field_definitions.translatable'))) {
+    foreach ($names as $name => $value) {
+      $fields[$name]->setTranslatable($value);
+    }
+  }
+  if ($entity_type->id() == 'node' && Drupal::state()->get('entity_test.node_remove_status_field')) {
+    unset($fields['status']);
+  }
+}
+
+/**
+ * Implements hook_entity_field_storage_info().
+ */
+function entity_test_entity_field_storage_info(EntityTypeInterface $entity_type) {
+  if ($entity_type->id() == 'entity_test_update') {
+    return \Drupal::state()->get('entity_test_update.additional_field_storage_definitions', array());
+  }
+}
+
+/**
+ * Creates a new bundle for entity_test entities.
+ *
+ * @param string $bundle
+ *   The machine-readable name of the bundle.
+ * @param string $text
+ *   (optional) The human-readable name of the bundle. If none is provided, the
+ *   machine name will be used.
+ * @param string $entity_type
+ *   (optional) The entity type for which the bundle is created. Defaults to
+ *   'entity_test'.
+ */
+function entity_test_create_bundle($bundle, $text = NULL, $entity_type = 'entity_test') {
+  $bundles = \Drupal::state()->get($entity_type . '.bundles') ?: array($entity_type => array('label' => 'Entity Test Bundle'));
+  $bundles += array($bundle => array('label' => $text ? $text : $bundle));
+  \Drupal::state()->set($entity_type . '.bundles', $bundles);
+
+  \Drupal::entityManager()->onBundleCreate($bundle, $entity_type);
+}
+
+/**
+ * Renames a bundle for entity_test entities.
+ *
+ * @param string $bundle_old
+ *   The machine-readable name of the bundle to rename.
+ * @param string $bundle_new
+ *   The new machine-readable name of the bundle.
+ * @param string $entity_type
+ *   (optional) The entity type for which the bundle is renamed. Defaults to
+ *   'entity_test'.
+ */
+function entity_test_rename_bundle($bundle_old, $bundle_new, $entity_type = 'entity_test') {
+  $bundles = \Drupal::state()->get($entity_type . '.bundles') ?: array($entity_type => array('label' => 'Entity Test Bundle'));
+  $bundles[$bundle_new] = $bundles[$bundle_old];
+  unset($bundles[$bundle_old]);
+  \Drupal::state()->set($entity_type . '.bundles', $bundles);
+
+  \Drupal::entityManager()->onBundleRename($bundle_old, $bundle_new, $entity_type);
+}
+
+/**
+ * Deletes a bundle for entity_test entities.
+ *
+ * @param string $bundle
+ *   The machine-readable name of the bundle to delete.
+ * @param string $entity_type
+ *   (optional) The entity type for which the bundle is deleted. Defaults to
+ *   'entity_test'.
+ */
+function entity_test_delete_bundle($bundle, $entity_type = 'entity_test') {
+  $bundles = \Drupal::state()->get($entity_type . '.bundles') ?: array($entity_type => array('label' => 'Entity Test Bundle'));
+  unset($bundles[$bundle]);
+  \Drupal::state()->set($entity_type . '.bundles', $bundles);
+
+  \Drupal::entityManager()->onBundleDelete($bundle, $entity_type);
+}
+
+/**
+ * Implements hook_entity_bundle_info().
+ */
+function entity_test_entity_bundle_info() {
+  $bundles = array();
+  $entity_types = \Drupal::entityManager()->getDefinitions();
+  foreach ($entity_types as $entity_type_id => $entity_type) {
+    if ($entity_type->getProvider() == 'entity_test') {
+      $bundles[$entity_type_id] = \Drupal::state()->get($entity_type_id . '.bundles') ?: array($entity_type_id => array('label' => 'Entity Test Bundle'));
+    }
+  }
+  return $bundles;
+}
+
+/**
+ * Implements hook_entity_view_mode_info_alter().
+ */
+function entity_test_entity_view_mode_info_alter(&$view_modes) {
+  $entity_info = \Drupal::entityManager()->getDefinitions();
+  foreach ($entity_info as $entity_type => $info) {
+    if ($entity_info[$entity_type]->getProvider() == 'entity_test' && !isset($view_modes[$entity_type])) {
+      $view_modes[$entity_type] = array(
+        'full' => array(
+          'label' => t('Full object'),
+          'status' => TRUE,
+          'cache' => TRUE,
+        ),
+        'teaser' => array(
+          'label' => t('Teaser'),
+          'status' => TRUE,
+          'cache' => TRUE,
+        ),
+      );
+    }
+  }
+}
+
+/**
+ * Implements hook_entity_form_mode_info_alter().
+ */
+function entity_test_entity_form_mode_info_alter(&$form_modes) {
+  $entity_info = \Drupal::entityManager()->getDefinitions();
+  foreach ($entity_info as $entity_type => $info) {
+    if ($entity_info[$entity_type]->getProvider() == 'entity_test') {
+      $form_modes[$entity_type] = array(
+        'compact' => array(
+          'label' => t('Compact version'),
+          'status' => TRUE,
+        ),
+      );
+    }
+  }
+}
+
+/**
+ * Implements hook_entity_extra_field_info().
+ */
+function entity_test_entity_extra_field_info() {
+  $extra['entity_test']['bundle_with_extra_fields'] = array(
+    'display' => array(
+      // Note: those extra fields do not currently display anything, they are
+      // just used in \Drupal\field_ui\Tests\EntityDisplayTest to test the
+      // behavior of entity display objects.
+      'display_extra_field' => array(
+        'label' => t('Display extra field'),
+        'description' => t('An extra field on the display side.'),
+        'weight' => 5,
+        'visible' => TRUE,
+      ),
+      'display_extra_field_hidden' => array(
+        'label' => t('Display extra field (hidden)'),
+        'description' => t('An extra field on the display side, hidden by default.'),
+        'visible' => FALSE,
+      ),
+    )
+  );
+
+  return $extra;
+}
+
+/**
+ * Implements hook_form_BASE_FORM_ID_alter().
+ */
+function entity_test_form_node_form_alter(&$form, FormStateInterface $form_state, $form_id) {
+  $langcode = $form_state->getFormObject()->getFormLangcode($form_state);
+  \Drupal::state()->set('entity_test.form_langcode', $langcode);
+}
+
+/**
+ * Loads a test entity.
+ *
+ * @param int $id
+ *   A test entity ID.
+ * @param bool $reset
+ *   A boolean indicating that the internal cache should be reset.
+ *
+ * @return \Drupal\entity_test\Entity\EntityTest
+ *   The loaded entity object, or NULL if the entity cannot be loaded.
+ */
+function entity_test_load($id, $reset = FALSE) {
+  return entity_load('entity_test', $id, $reset);
+}
+
+/**
+ * Loads a test entity.
+ *
+ * @param int $id
+ *   A test entity ID.
+ * @param bool $reset
+ *   A boolean indicating that the internal cache should be reset.
+ *
+ * @return \Drupal\entity_test\Entity\EntityTestRev
+ *   The loaded entity object, or NULL if the entity cannot be loaded.
+ */
+function entity_test_rev_load($id, $reset = FALSE) {
+  return entity_load('entity_test_rev', $id, $reset);
+}
+
+/**
+ * Loads a test entity.
+ *
+ * @param int $id
+ *   A test entity ID.
+ * @param bool $reset
+ *   A boolean indicating that the internal cache should be reset.
+ *
+ * @return \Drupal\entity_test\Entity\EntityTestMul
+ *   The loaded entity object, or FALSE if the entity cannot be loaded.
+ */
+function entity_test_mul_load($id, $reset = FALSE) {
+  return entity_load('entity_test_mul', $id, $reset);
+}
+
+/**
+ * Loads a test entity.
+ *
+ * @param int $id
+ *   A test entity ID.
+ * @param bool $reset
+ *   A boolean indicating that the internal cache should be reset.
+ *
+ * @return \Drupal\entity_test\Entity\EntityTestMulRev
+ *   The loaded entity object, or NULL if the entity cannot be loaded.
+ */
+function entity_test_mulrev_load($id, $reset = FALSE) {
+  return entity_load('entity_test_mulrev', $id, $reset);
+}
+
+/**
+ * Implements hook_ENTITY_TYPE_insert() for 'entity_test'.
+ */
+function entity_test_entity_test_insert($entity) {
+  if ($entity->name->value == 'fail_insert') {
+    throw new Exception("Test exception rollback.");
+  }
+}
+
+/**
+ * Implements hook_entity_field_access().
+ *
+ * @see \Drupal\system\Tests\Entity\FieldAccessTest::testFieldAccess()
+ */
+function entity_test_entity_field_access($operation, FieldDefinitionInterface $field_definition, AccountInterface $account, FieldItemListInterface $items = NULL) {
+  if ($field_definition->getName() == 'field_test_text') {
+    if ($items) {
+      if ($items->value == 'no access value') {
+        return AccessResult::forbidden()->cacheUntilEntityChanges($items->getEntity());
+      }
+      elseif ($operation == 'edit' && $items->value == 'no edit access value') {
+        return AccessResult::forbidden()->cacheUntilEntityChanges($items->getEntity());
+      }
+    }
+  }
+  if ($field = \Drupal::state()->get('views_field_access_test-field')) {
+    if ($field_definition->getName() === $field) {
+      $result = AccessResult::allowedIfHasPermission($account, 'view test entity field');
+      // For test purposes we want to actively deny access.
+      if ($result->isNeutral()) {
+        $result = AccessResult::forbidden();
+      }
+      return $result;
+    }
+  }
+
+  // No opinion.
+  return AccessResult::neutral();
+}
+
+/**
+ * Implements hook_entity_field_access_alter().
+ *
+ * @see \Drupal\system\Tests\Entity\FieldAccessTest::testFieldAccess()
+ */
+function entity_test_entity_field_access_alter(array &$grants, array $context) {
+  if ($context['field_definition']->getName() == 'field_test_text' && $context['items']->value == 'access alter value') {
+    $grants[':default'] = AccessResult::forbidden()->inheritCacheability($grants[':default'])->cacheUntilEntityChanges($context['items']->getEntity());
+  }
+}
+
+/**
+ * Implements hook_entity_form_display_alter().
+ */
+function entity_test_entity_form_display_alter(EntityFormDisplay $form_display, $context) {
+  // Make the field_test_text field 42 characters for entity_test_mul.
+  if ($context['entity_type'] == 'entity_test') {
+    if ($component_options = $form_display->getComponent('field_test_text')) {
+      $component_options['settings']['size'] = 42;
+      $form_display->setComponent('field_test_text', $component_options);
+    }
+  }
+}
+
+/**
+ * Implements hook_entity_presave().
+ */
+function entity_test_entity_presave(EntityInterface $entity) {
+  if (isset($GLOBALS['entity_test_throw_exception'])) {
+    throw new Exception('Entity presave exception', 1);
+  }
+
+  if ($entity->getEntityType()->id() == 'entity_view_display') {
+    $entity->setThirdPartySetting('entity_test', 'foo', 'bar');
+  }
+}
+
+/**
+ * Implements hook_entity_predelete().
+ */
+function entity_test_entity_predelete(EntityInterface $entity) {
+  if (isset($GLOBALS['entity_test_throw_exception'])) {
+    throw new Exception('Entity predelete exception', 2);
+  }
+}
+
+/**
+ * Implements hook_entity_operation_alter().
+ */
+function entity_test_entity_operation_alter(array &$operations, EntityInterface $entity) {
+  $valid_entity_type_ids = [
+    'user_role',
+    'block',
+  ];
+  if (in_array($entity->getEntityTypeId(), $valid_entity_type_ids)) {
+    if (\Drupal::service('router.route_provider')->getRouteByName("entity.{$entity->getEntityTypeId()}.test_operation")) {
+      $operations['test_operation'] = [
+        'title' => format_string('Test Operation: @label', ['@label' => $entity->label()]),
+        'url' => Url::fromRoute("entity.{$entity->getEntityTypeId()}.test_operation", [$entity->getEntityTypeId() => $entity->id()]),
+        'weight' => 50,
+      ];
+    }
+  }
+}
+
+/**
+ * Implements hook_entity_translation_insert().
+ */
+function entity_test_entity_translation_insert(EntityInterface $translation) {
+  _entity_test_record_hooks('entity_translation_insert', $translation->language()->getId());
+}
+
+/**
+ * Implements hook_entity_translation_delete().
+ */
+function entity_test_entity_translation_delete(EntityInterface $translation) {
+  _entity_test_record_hooks('entity_translation_delete', $translation->language()->getId());
+}
+
+/**
+ * Implements hook_ENTITY_TYPE_translation_insert() for 'entity_test_mul'.
+ */
+function entity_test_entity_test_mul_translation_insert(EntityInterface $translation) {
+  _entity_test_record_hooks('entity_test_mul_translation_insert', $translation->language()->getId());
+}
+
+/**
+ * Implements hook_ENTITY_TYPE_translation_delete() for 'entity_test_mul'.
+ */
+function entity_test_entity_test_mul_translation_delete(EntityInterface $translation) {
+  _entity_test_record_hooks('entity_test_mul_translation_delete', $translation->language()->getId());
+}
+
+/**
+ * Implements hook_ENTITY_TYPE_translation_insert() for 'entity_test_mulrev'.
+ */
+function entity_test_entity_test_mul_changed_translation_insert(EntityInterface $translation) {
+  _entity_test_record_hooks('entity_test_mul_changed_translation_insert', $translation->language()->getId());
+}
+
+/**
+ * Implements hook_ENTITY_TYPE_translation_delete().
+ */
+function entity_test_entity_test_mul_changed_translation_delete(EntityInterface $translation) {
+  _entity_test_record_hooks('entity_test_mul_changed_translation_delete', $translation->language()->getId());
+}
+
+/**
+ * Implements hook_ENTITY_TYPE_translation_insert().
+ */
+function entity_test_entity_test_mulrev_translation_insert(EntityInterface $translation) {
+  _entity_test_record_hooks('entity_test_mulrev_translation_insert', $translation->language()->getId());
+}
+
+/**
+ * Implements hook_ENTITY_TYPE_translation_delete() for 'entity_test_mulrev'.
+ */
+function entity_test_entity_test_mulrev_translation_delete(EntityInterface $translation) {
+  _entity_test_record_hooks('entity_test_mulrev_translation_delete', $translation->language()->getId());
+}
+
+/**
+ * Implements hook_ENTITY_TYPE_translation_insert() for 'entity_test_mulrev'.
+ */
+function entity_test_entity_test_mulrev_changed_translation_insert(EntityInterface $translation) {
+  _entity_test_record_hooks('entity_test_mulrev_changed_translation_insert', $translation->language()->getId());
+}
+
+/**
+ * Implements hook_ENTITY_TYPE_translation_delete().
+ */
+function entity_test_entity_test_mulrev_changed_translation_delete(EntityInterface $translation) {
+  _entity_test_record_hooks('entity_test_mulrev_changed_translation_delete', $translation->language()->getId());
+}
+
+/**
+ * Implements hook_ENTITY_TYPE_translation_insert() for 'entity_test_mul_langcode_key'.
+ */
+function entity_test_entity_test_mul_langcode_key_translation_insert(EntityInterface $translation) {
+  _entity_test_record_hooks('entity_test_mul_langcode_key_translation_insert', $translation->language()->getId());
+}
+
+/**
+ * Implements hook_ENTITY_TYPE_translation_delete() for 'entity_test_mul_langcode_key'.
+ */
+function entity_test_entity_test_mul_langcode_key_translation_delete(EntityInterface $translation) {
+  _entity_test_record_hooks('entity_test_mul_langcode_key_translation_delete', $translation->language()->getId());
+}
+
+/**
+ * Field default value callback.
+ *
+ * @param \Drupal\Core\Entity\FieldableEntityInterface $entity
+ *   The entity being created.
+ * @param \Drupal\Core\Field\FieldDefinitionInterface $definition
+ *   The field definition.
+ *
+ * @return array
+ *   An array of default values, in the same format as the $default_value
+ *   property.
+ *
+ * @see \Drupal\field\Entity\FieldConfig::$default_value
+ */
+function entity_test_field_default_value(FieldableEntityInterface $entity, FieldDefinitionInterface $definition) {
+  // Include the field name and entity language in the generated values to check
+  // that they are correctly passed.
+  $string = $definition->getName() . '_' . $entity->language()->getId();
+  // Return a "default value" with multiple items.
+  return array(
+    array(
+      'shape' => "shape:0:$string",
+      'color' => "color:0:$string",
+    ),
+    array(
+      'shape' => "shape:1:$string",
+      'color' => "color:1:$string",
+    ),
+  );
+}
+
+/**
+ * Helper function to be used to record hook invocations.
+ *
+ * @param string $hook
+ *   The hook name.
+ * @param mixed $data
+ *   Arbitrary data associated to the hook invocation.
+ */
+function _entity_test_record_hooks($hook, $data) {
+  $state = \Drupal::state();
+  $key = 'entity_test.hooks';
+  $hooks = $state->get($key);
+  $hooks[$hook] = $data;
+  $state->set($key, $hooks);
+}
+
+/**
+ * Implements hook_entity_prepare_view().
+ */
+function entity_test_entity_prepare_view($entity_type, array $entities, array $displays) {
+  // Add a dummy field item attribute on field_test_text if it exists.
+  if ($entity_type == 'entity_test') {
+    foreach ($entities as $entity) {
+      if ($entity->hasField('field_test_text') && $displays[$entity->bundle()]->getComponent('field_test_text')) {
+        foreach ($entity->get('field_test_text') as $item) {
+          $item->_attributes += array('data-field-item-attr' => 'foobar');
+        }
+      }
+    }
+  }
+}
+
+/**
+ * Implements hook_entity_access().
+ */
+function entity_test_entity_access(EntityInterface $entity, $operation, AccountInterface $account, $langcode) {
+  \Drupal::state()->set('entity_test_entity_access', TRUE);
+
+  // Attempt to allow access to entities with the title forbid_access,
+  // this will be overridden by
+  // \Drupal\entity_test\EntityTestAccessControlHandler::checkAccess().
+  if ($entity->label() == 'forbid_access') {
+    return AccessResult::allowed();
+  }
+
+  // Uncacheable because the access result depends on a State key-value pair and
+  // might therefore change at any time.
+  $condition = \Drupal::state()->get("entity_test_entity_access.{$operation}." . $entity->id(), FALSE);
+  return AccessResult::allowedIf($condition)->setCacheMaxAge(0);
+}
+
+/**
+ * Implements hook_ENTITY_TYPE_access() for 'entity_test'.
+ */
+function entity_test_entity_test_access(EntityInterface $entity, $operation, AccountInterface $account, $langcode) {
+  \Drupal::state()->set('entity_test_entity_test_access', TRUE);
+
+  // No opinion.
+  return AccessResult::neutral();
+}
+
+/**
+ * Implements hook_entity_create_access().
+ */
+function entity_test_entity_create_access(AccountInterface $account, $context, $entity_bundle) {
+  \Drupal::state()->set('entity_test_entity_create_access', TRUE);
+
+  // No opinion.
+  return AccessResult::neutral();
+}
+
+/**
+ * Implements hook_ENTITY_TYPE_create_access() for 'entity_test'.
+ */
+function entity_test_entity_test_create_access(AccountInterface $account, $context, $entity_bundle) {
+  \Drupal::state()->set('entity_test_entity_test_create_access', TRUE);
+
+  // No opinion.
+  return AccessResult::neutral();
+}

core/modules/system/tests/modules/entity_test/entity_test.permissions.yml

@@ -0,0 +1,9 @@
+administer entity_test content:
+  title: 'Administer entity_test content'
+  description: 'Manage entity_test content'
+view test entity:
+  title: 'View test entities'
+view test entity translations:
+  title: 'View translations of test entities'
+view test entity field:
+  title: 'View test entity field'

core/modules/system/tests/modules/entity_test/entity_test.routing.yml

@@ -0,0 +1,80 @@
+entity.entity_test.canonical:
+  path: '/entity_test/{entity_test}'
+  defaults:
+    _entity_view: 'entity_test.full'
+    _title: 'Test full view mode'
+  requirements:
+    _access: 'TRUE'
+
+entity.entity_test.render_options:
+  path: '/entity_test_converter/{foo}'
+  options:
+    parameters:
+      foo:
+        type: 'entity:entity_test'
+  defaults:
+    _entity_view: 'entity_test.full'
+  requirements:
+    _access: 'TRUE'
+
+entity.entity_test.render_no_view_mode:
+  path: '/entity_test_no_view_mode/{entity_test}'
+  defaults:
+    _entity_view: 'entity_test'
+  requirements:
+    _access: 'TRUE'
+
+entity.entity_test.collection_referencing_entities:
+  path: '/entity_test/list/{entity_reference_field_name}/{referenced_entity_type}/{referenced_entity_id}'
+  defaults:
+    _controller: '\Drupal\entity_test\Controller\EntityTestController::listReferencingEntities'
+    _title: 'List entity_test entities referencing the given entity'
+  requirements:
+    _access: 'TRUE'
+
+entity.entity_test.collection_labels_alphabetically:
+  path: '/entity_test/list_labels_alphabetically/{entity_type_id}'
+  defaults:
+    _controller: '\Drupal\entity_test\Controller\EntityTestController::listEntitiesAlphabetically'
+    _title: 'List labels of entities of the given entity type alphabetically'
+  requirements:
+    _access: 'TRUE'
+
+entity.entity_test.collection_empty:
+  path: '/entity_test/list_empty/{entity_type_id}'
+  defaults:
+    _controller: '\Drupal\entity_test\Controller\EntityTestController::listEntitiesEmpty'
+    _title: 'Empty list of entities of the given entity type, empty because no entities match the query'
+  requirements:
+    _access: 'TRUE'
+
+entity.entity_test.collection:
+  path: '/entity_test/list'
+  defaults:
+    _entity_list: entity_test
+  requirements:
+    _access: 'TRUE'
+
+entity.entity_test_rev.revision:
+  path: '/entity_test_rev/{entity_test_rev}/revision/{entity_test_rev_revision}/view'
+  defaults:
+    _entity_view: 'entity_test_rev'
+  requirements:
+    _access: 'TRUE'
+
+entity.block.test_operation:
+  path: '/admin/structure/block/manage/{block}/test_operation'
+  defaults:
+    _entity_view: 'entity_test'
+  requirements:
+    _access: 'TRUE'
+
+entity.user_role.test_operation:
+  path: '/admin/people/roles/manage/{user_role}/test_operation'
+  defaults:
+    _entity_view: 'entity_test'
+  requirements:
+    _access: 'TRUE'
+
+route_callbacks:
+  - '\Drupal\entity_test\Routing\EntityTestRoutes::routes'

core/modules/system/tests/modules/entity_test/entity_test.services.yml

@@ -0,0 +1,10 @@
+services:
+  entity_test.definition.subscriber:
+    class: Drupal\entity_test\EntityTestDefinitionSubscriber
+    arguments: ['@state']
+    tags:
+      - { name: event_subscriber }
+  cache_context.entity_test_view_grants:
+    class: Drupal\entity_test\Cache\EntityTestViewGrantsCacheContext
+    tags:
+      - { name: cache.context }

core/modules/system/tests/modules/entity_test/entity_test.views.inc

@@ -0,0 +1,9 @@
+<?php
+
+/**
+ * Implements hook_views_data_alter().
+ */
+function entity_test_views_data_alter(&$data) {
+  $data['entity_test']['name_alias'] = $data['entity_test']['name'];
+  $data['entity_test']['name_alias']['field']['real field'] = 'name';
+}

core/modules/system/tests/modules/entity_test/src/Cache/EntityTestViewGrantsCacheContext.php

@@ -0,0 +1,35 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\entity_test\Cache\EntityTestViewGrantsCacheContext.
+ */
+
+namespace Drupal\entity_test\Cache;
+
+use Drupal\Core\Cache\Context\CacheContextInterface;
+
+/**
+ * Defines the entity_test view grants cache context service.
+ *
+ * @see \Drupal\node\Cache\NodeAccessViewGrantsCacheContext
+ */
+class EntityTestViewGrantsCacheContext implements CacheContextInterface {
+
+  /**
+   * {@inheritdoc}
+   */
+  public static function getLabel() {
+    return t("Entity test view grants");
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function getContext() {
+    // Return a constant value, so we can fetch render cache both in actual
+    // requests and test code itself.
+    return '299792458';
+  }
+
+}

core/modules/system/tests/modules/entity_test/src/Controller/EntityTestController.php

@@ -0,0 +1,197 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\entity_test\Controller\EntityTestController.
+ */
+
+namespace Drupal\entity_test\Controller;
+
+use Drupal\Core\Cache\Cache;
+use Drupal\Core\Controller\ControllerBase;
+use Drupal\Core\Entity\Query\QueryFactory;
+use Drupal\Core\Routing\RouteMatchInterface;
+use Symfony\Component\DependencyInjection\ContainerInterface;
+
+/**
+ * Controller routines for entity_test routes.
+ */
+class EntityTestController extends ControllerBase {
+
+  /**
+   * The entity query factory.
+   *
+   * @var \Drupal\Core\Entity\Query\QueryFactory
+   */
+  protected $entityQueryFactory;
+
+  /**
+   * Constructs a new EntityTestController.
+   *
+   * @param \Drupal\Core\Entity\Query\QueryFactory
+   *   The entity query factory.
+   */
+  public function __construct(QueryFactory $entity_query_factory) {
+    $this->entityQueryFactory = $entity_query_factory;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public static function create(ContainerInterface $container) {
+    return new static(
+      $container->get('entity.query')
+    );
+  }
+
+  /**
+   * Displays the 'Add new entity_test' form.
+   *
+   * @param string $entity_type_id
+   *   Name of the entity type for which a create form should be displayed.
+   *
+   * @return array
+   *   The processed form for a new entity_test.
+   *
+   * @see \Drupal\entity_test\Routing\EntityTestRoutes::routes()
+   */
+  public function testAdd($entity_type_id) {
+    $entity = entity_create($entity_type_id, array());
+    $form = $this->entityFormBuilder()->getForm($entity);
+    $form['#title'] = $this->t('Create an @type', array('@type' => $entity_type_id));
+    return $form;
+  }
+
+  /**
+   * Displays the 'Edit existing entity_test' form.
+   *
+   * @param \Drupal\Core\Routing\RouteMatchInterface $route_match
+   *   The route match object to get entity type from.
+   * @param string $entity_type_id
+   *   The entity type ID.
+   *
+   * @return array
+   *   The processed form for the edited entity.
+   *
+   * @see \Drupal\entity_test\Routing\EntityTestRoutes::routes()
+   */
+  public function testEdit(RouteMatchInterface $route_match, $entity_type_id) {
+    $entity = $route_match->getParameter($entity_type_id);
+    $form = $this->entityFormBuilder()->getForm($entity);
+    $form['#title'] = $entity->label();
+    return $form;
+  }
+
+  /**
+   * Returns an empty page.
+   *
+   * @see \Drupal\entity_test\Routing\EntityTestRoutes::routes()
+   */
+  public function testAdmin() {
+    return [];
+  }
+
+  /**
+   * List entity_test entities referencing the given entity.
+   *
+   * @param string $entity_reference_field_name
+   *   The name of the entity_reference field to use in the query.
+   * @param string $referenced_entity_type
+   *   The type of the entity being referenced.
+   * @param int $referenced_entity_id
+   *   The ID of the entity being referenced.
+   *
+   * @return array
+   *   A renderable array.
+   */
+  public function listReferencingEntities($entity_reference_field_name, $referenced_entity_type, $referenced_entity_id) {
+    // Early return if the referenced entity does not exist (or is deleted).
+    $referenced_entity = $this->entityManager()
+      ->getStorage($referenced_entity_type)
+      ->load($referenced_entity_id);
+    if ($referenced_entity === NULL) {
+      return array();
+    }
+
+    $query = $this->entityQueryFactory
+      ->get('entity_test')
+      ->condition($entity_reference_field_name . '.target_id', $referenced_entity_id);
+    $entities = $this->entityManager()
+      ->getStorage('entity_test')
+      ->loadMultiple($query->execute());
+    return $this->entityManager()
+      ->getViewBuilder('entity_test')
+      ->viewMultiple($entities, 'full');
+  }
+
+  /**
+   * List entities of the given entity type labels, sorted alphabetically.
+   *
+   * @param string $entity_type_id
+   *   The type of the entity being listed.
+   *
+   * @return array
+   *   A renderable array.
+   */
+  public function listEntitiesAlphabetically($entity_type_id) {
+    $entity_type_definition = $this->entityManager()->getDefinition($entity_type_id);
+    $query = $this->entityQueryFactory->get($entity_type_id);
+
+    // Sort by label field, if any.
+    if ($label_field = $entity_type_definition->getKey('label')) {
+      $query->sort($label_field);
+    }
+
+    $entities = $this->entityManager()
+      ->getStorage($entity_type_id)
+      ->loadMultiple($query->execute());
+
+    $cache_tags = [];
+    $labels = [];
+    foreach ($entities as $entity) {
+      $labels[] = $entity->label();
+      $cache_tags = Cache::mergeTags($cache_tags, $entity->getCacheTags());
+    }
+    // Always associate the list cache tag, otherwise the cached empty result
+    // wouldn't be invalidated. This would continue to show nothing matches the
+    // query, even though a newly created entity might match the query.
+    $cache_tags = Cache::mergeTags($cache_tags, $entity_type_definition->getListCacheTags());
+
+    return [
+      '#theme' => 'item_list',
+      '#items' => $labels,
+      '#title' => $entity_type_id . ' entities',
+      '#cache' => [
+        'contexts' => $entity_type_definition->getListCacheContexts(),
+        'tags' => $cache_tags,
+      ],
+    ];
+  }
+
+
+  /**
+   * Empty list of entities of the given entity type.
+   *
+   * Empty because no entities match the query. That may seem contrived, but it
+   * is an excellent way for testing whether an entity's list cache tags are
+   * working as expected.
+   *
+   * @param string $entity_type_id
+   *   The type of the entity being listed.
+   *
+   * @return array
+   *   A renderable array.
+   */
+  public function listEntitiesEmpty($entity_type_id) {
+    $entity_type_definition = $this->entityManager()->getDefinition($entity_type_id);
+    return [
+      '#theme' => 'item_list',
+      '#items' => [],
+      '#cache' => [
+        'contexts' => $entity_type_definition->getListCacheContexts(),
+        'tags' => $entity_type_definition->getListCacheTags(),
+      ],
+    ];
+  }
+
+}

core/modules/system/tests/modules/entity_test/src/Entity/EntityTest.php

@@ -0,0 +1,184 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\entity_test\Entity\EntityTest.
+ */
+
+namespace Drupal\entity_test\Entity;
+
+use Drupal\Core\Entity\ContentEntityBase;
+use Drupal\Core\Entity\EntityTypeInterface;
+use Drupal\Core\Field\BaseFieldDefinition;
+use Drupal\Core\Entity\EntityStorageInterface;
+use Drupal\user\EntityOwnerInterface;
+use Drupal\user\UserInterface;
+
+/**
+ * Defines the test entity class.
+ *
+ * @ContentEntityType(
+ *   id = "entity_test",
+ *   label = @Translation("Test entity"),
+ *   handlers = {
+ *     "list_builder" = "Drupal\entity_test\EntityTestListBuilder",
+ *     "view_builder" = "Drupal\entity_test\EntityTestViewBuilder",
+ *     "access" = "Drupal\entity_test\EntityTestAccessControlHandler",
+ *     "form" = {
+ *       "default" = "Drupal\entity_test\EntityTestForm",
+ *       "delete" = "Drupal\entity_test\EntityTestDeleteForm"
+ *     },
+ *     "translation" = "Drupal\content_translation\ContentTranslationHandler",
+ *     "views_data" = "Drupal\entity_test\EntityTestViewsData"
+ *   },
+ *   base_table = "entity_test",
+ *   persistent_cache = FALSE,
+ *   list_cache_contexts = { "entity_test_view_grants" },
+ *   entity_keys = {
+ *     "id" = "id",
+ *     "uuid" = "uuid",
+ *     "bundle" = "type",
+ *     "label" = "name",
+ *     "langcode" = "langcode",
+ *   },
+ *   links = {
+ *     "canonical" = "/entity_test/{entity_test}",
+ *     "edit-form" = "/entity_test/manage/{entity_test}",
+ *     "delete-form" = "/entity_test/delete/entity_test/{entity_test}",
+ *   },
+ *   field_ui_base_route = "entity.entity_test.admin_form",
+ * )
+ */
+class EntityTest extends ContentEntityBase implements EntityOwnerInterface {
+
+  /**
+   * {@inheritdoc}
+   */
+  public static function preCreate(EntityStorageInterface $storage, array &$values) {
+    parent::preCreate($storage, $values);
+    if (empty($values['type'])) {
+      $values['type'] = $storage->getEntityTypeId();
+    }
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public static function baseFieldDefinitions(EntityTypeInterface $entity_type) {
+    $fields['id'] = BaseFieldDefinition::create('integer')
+      ->setLabel(t('ID'))
+      ->setDescription(t('The ID of the test entity.'))
+      ->setReadOnly(TRUE)
+      ->setSetting('unsigned', TRUE);
+
+    $fields['uuid'] = BaseFieldDefinition::create('uuid')
+      ->setLabel(t('UUID'))
+      ->setDescription(t('The UUID of the test entity.'))
+      ->setReadOnly(TRUE);
+
+    $fields['langcode'] = BaseFieldDefinition::create('language')
+      ->setLabel(t('Language code'))
+      ->setDescription(t('The language code of the test entity.'))
+      ->setTranslatable(TRUE);
+
+    $fields['name'] = BaseFieldDefinition::create('string')
+      ->setLabel(t('Name'))
+      ->setDescription(t('The name of the test entity.'))
+      ->setTranslatable(TRUE)
+      ->setSetting('max_length', 32)
+      ->setDisplayOptions('view', array(
+        'label' => 'hidden',
+        'type' => 'string',
+        'weight' => -5,
+      ))
+      ->setDisplayOptions('form', array(
+        'type' => 'string_textfield',
+        'weight' => -5,
+      ));
+
+    // @todo: Add allowed values validation.
+    $fields['type'] = BaseFieldDefinition::create('string')
+      ->setLabel(t('Type'))
+      ->setDescription(t('The bundle of the test entity.'))
+      ->setRequired(TRUE);
+
+    $fields['created'] = BaseFieldDefinition::create('created')
+      ->setLabel(t('Authored on'))
+      ->setDescription(t('Time the entity was created'))
+      ->setTranslatable(TRUE);
+
+    $fields['user_id'] = BaseFieldDefinition::create('entity_reference')
+      ->setLabel(t('User ID'))
+      ->setDescription(t('The ID of the associated user.'))
+      ->setSetting('target_type', 'user')
+      ->setSetting('handler', 'default')
+      // Default EntityTest entities to have the root user as the owner, to
+      // simplify testing.
+      ->setDefaultValue(array(0 => array('target_id' => 1)))
+      ->setTranslatable(TRUE)
+      ->setDisplayOptions('form', array(
+        'type' => 'entity_reference_autocomplete',
+        'weight' => -1,
+        'settings' => array(
+          'match_operator' => 'CONTAINS',
+          'size' => '60',
+          'placeholder' => '',
+        ),
+      ));
+
+    return $fields;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function getOwner() {
+    return $this->get('user_id')->entity;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function getOwnerId() {
+    return $this->get('user_id')->target_id;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function setOwnerId($uid) {
+    $this->set('user_id', $uid);
+    return $this;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function setOwner(UserInterface $account) {
+    $this->set('user_id', $account->id());
+    return $this;
+  }
+
+  /**
+   * Sets the name.
+   *
+   * @param string $name
+   *   Name of the entity.
+   *
+   * @return $this
+   */
+  public function setName($name) {
+    $this->set('name', $name);
+    return $this;
+  }
+
+  /**
+   * Returns the name.
+   *
+   * @return string
+   */
+  public function getName() {
+    return $this->get('name')->value;
+  }
+
+}

core/modules/system/tests/modules/entity_test/src/Entity/EntityTestBaseFieldDisplay.php

@@ -0,0 +1,76 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\entity_test\Entity\EntityTestBaseFieldDisplay.
+ */
+
+namespace Drupal\entity_test\Entity;
+
+use Drupal\Core\Entity\EntityTypeInterface;
+use Drupal\Core\Field\BaseFieldDefinition;
+
+/**
+ * Defines a test entity class for base fields display.
+ *
+ * @ContentEntityType(
+ *   id = "entity_test_base_field_display",
+ *   label = @Translation("Test entity - base field display"),
+ *   handlers = {
+ *     "access" = "Drupal\entity_test\EntityTestAccessControlHandler",
+ *     "form" = {
+ *       "default" = "Drupal\entity_test\EntityTestForm"
+ *     },
+ *     "translation" = "Drupal\content_translation\ContentTranslationHandler"
+ *   },
+ *   base_table = "entity_test",
+ *   entity_keys = {
+ *     "id" = "id",
+ *     "uuid" = "uuid",
+ *     "bundle" = "type"
+ *   },
+ *   links = {
+ *     "edit-form" = "/entity_test_base_field_display/manage/{entity_test_base_field_display}",
+ *   },
+ *   field_ui_base_route = "entity.entity_test_base_field_display.admin_form",
+ * )
+ */
+class EntityTestBaseFieldDisplay extends EntityTest {
+
+  /**
+   * {@inheritdoc}
+   */
+  public static function baseFieldDefinitions(EntityTypeInterface $entity_type) {
+    $fields = parent::baseFieldDefinitions($entity_type);
+
+    $fields['test_no_display'] = BaseFieldDefinition::create('text')
+      ->setLabel(t('Field with no display'));
+
+    $fields['test_display_configurable'] = BaseFieldDefinition::create('text')
+      ->setLabel(t('Field with configurable display'))
+      ->setDisplayOptions('view', array(
+        'type' => 'text_default',
+        'weight' => 10,
+      ))
+      ->setDisplayConfigurable('view', TRUE)
+      ->setDisplayOptions('form', array(
+        'type' => 'text_textfield',
+        'weight' => 10,
+      ))
+      ->setDisplayConfigurable('form', TRUE);
+
+    $fields['test_display_non_configurable'] = BaseFieldDefinition::create('text')
+      ->setLabel(t('Field with non-configurable display'))
+      ->setDisplayOptions('view', array(
+        'type' => 'text_default',
+        'weight' => 11,
+      ))
+      ->setDisplayOptions('form', array(
+        'type' => 'text_textfield',
+        'weight' => 11,
+      ));
+
+    return $fields;
+  }
+
+}

core/modules/system/tests/modules/entity_test/src/Entity/EntityTestCache.php

@@ -0,0 +1,33 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\entity_test\Entity\EntityTestCache.
+ */
+
+namespace Drupal\entity_test\Entity;
+
+/**
+ * Defines the test entity class.
+ *
+ * @ContentEntityType(
+ *   id = "entity_test_cache",
+ *   label = @Translation("Test entity with field cache"),
+ *   handlers = {
+ *     "access" = "Drupal\entity_test\EntityTestAccessControlHandler",
+ *     "form" = {
+ *       "default" = "Drupal\entity_test\EntityTestForm"
+ *     },
+ *     "translation" = "Drupal\content_translation\ContentTranslationHandler"
+ *   },
+ *   base_table = "entity_test",
+ *   entity_keys = {
+ *     "id" = "id",
+ *     "uuid" = "uuid",
+ *     "bundle" = "type"
+ *   }
+ * )
+ */
+class EntityTestCache extends EntityTest {
+
+}

core/modules/system/tests/modules/entity_test/src/Entity/EntityTestCompositeConstraint.php

@@ -0,0 +1,57 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\entity_test\Entity\EntityTestCompositeConstraint.
+ */
+
+namespace Drupal\entity_test\Entity;
+use Drupal\Core\Entity\EntityTypeInterface;
+
+/**
+ * Defines a test class for testing composite constraints.
+ *
+ * @ContentEntityType(
+ *   id = "entity_test_composite_constraint",
+ *   label = @Translation("Test entity constraints with composite constraint"),
+ *   entity_keys = {
+ *     "id" = "id",
+ *     "uuid" = "uuid",
+ *     "bundle" = "type",
+ *     "label" = "name"
+ *   },
+ *   handlers = {
+ *     "form" = {
+ *       "default" = "Drupal\entity_test\EntityTestForm"
+ *     }
+ *   },
+ *   base_table = "entity_test_composite_constraint",
+ *   persistent_cache = FALSE,
+ *   constraints = {
+ *     "EntityTestComposite" = {},
+ *     "EntityTestEntityLevel" = {},
+ *   }
+ * )
+ */
+class EntityTestCompositeConstraint extends EntityTest {
+
+  /**
+   * {@inheritdoc}
+   */
+  public static function baseFieldDefinitions(EntityTypeInterface $entity_type) {
+    $fields = parent::baseFieldDefinitions($entity_type);
+
+    $fields['name']->setDisplayOptions('form', array(
+      'type' => 'string',
+      'weight' => 0,
+    ));
+
+    $fields['type']->setDisplayOptions('form', array(
+      'type' => 'entity_reference_autocomplete',
+      'weight' => 0,
+    ));
+
+    return $fields;
+  }
+
+}

core/modules/system/tests/modules/entity_test/src/Entity/EntityTestConstraintViolation.php

@@ -0,0 +1,50 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\entity_test\Entity\EntityTestConstraintViolation.
+ */
+
+namespace Drupal\entity_test\Entity;
+
+use Drupal\Core\Entity\EntityTypeInterface;
+
+/**
+ * Defines the test entity class for testing entity constraint violations.
+ *
+ * @ContentEntityType(
+ *   id = "entity_test_constraint_violation",
+ *   label = @Translation("Test entity constraint violation"),
+ *   handlers = {
+ *     "form" = {
+ *       "default" = "Drupal\entity_test\EntityTestForm"
+ *     }
+ *   },
+ *   base_table = "entity_test",
+ *   persistent_cache = FALSE,
+ *   entity_keys = {
+ *     "id" = "id",
+ *     "uuid" = "uuid",
+ *     "bundle" = "type",
+ *     "label" = "name"
+ *   }
+ * )
+ */
+class EntityTestConstraintViolation extends EntityTest {
+
+  /**
+   * {@inheritdoc}
+   */
+  public static function baseFieldDefinitions(EntityTypeInterface $entity_type) {
+    $fields = parent::baseFieldDefinitions($entity_type);
+
+    $fields['name']->setDisplayOptions('form', array(
+      'type' => 'string',
+      'weight' => 0,
+    ));
+    $fields['name']->addConstraint('FieldWidgetConstraint', array());
+
+    return $fields;
+  }
+
+}

core/modules/system/tests/modules/entity_test/src/Entity/EntityTestConstraints.php

@@ -0,0 +1,57 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\entity_test\Entity\EntityTestConstraints.
+ */
+
+namespace Drupal\entity_test\Entity;
+
+use Drupal\Core\Entity\EntityChangedTrait;
+use Drupal\Core\Entity\EntityTypeInterface;
+use Drupal\Core\Entity\EntityChangedInterface;
+use Drupal\Core\Field\BaseFieldDefinition;
+
+/**
+ * Defines a test class for testing the definition of entity level constraints.
+ *
+ * @ContentEntityType(
+ *   id = "entity_test_constraints",
+ *   label = @Translation("Test entity constraints"),
+ *   entity_keys = {
+ *     "id" = "id",
+ *     "uuid" = "uuid",
+ *     "bundle" = "type",
+ *     "label" = "name"
+ *   },
+ *   base_table = "entity_test_constraints",
+ *   persistent_cache = FALSE,
+ *   constraints = {
+ *     "NotNull" = {}
+ *   }
+ * )
+ */
+class EntityTestConstraints extends EntityTest implements EntityChangedInterface {
+
+  use EntityChangedTrait;
+
+  /**
+   * {@inheritdoc}
+   */
+  public static function baseFieldDefinitions(EntityTypeInterface $entity_type) {
+    $fields = parent::baseFieldDefinitions($entity_type);
+
+    $fields['changed'] = BaseFieldDefinition::create('changed')
+      ->setLabel(t('Changed'));
+
+    return $fields;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function getChangedTime() {
+    return $this->get('changed')->value;
+  }
+
+}

core/modules/system/tests/modules/entity_test/src/Entity/EntityTestDefaultAccess.php

@@ -0,0 +1,25 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\entity_test\Entity\EntityTestDefaultAccess.
+ */
+
+namespace Drupal\entity_test\Entity;
+
+/**
+ * Defines a test entity class with no access control handler.
+ *
+ * @ContentEntityType(
+ *   id = "entity_test_default_access",
+ *   label = @Translation("Test entity with default access"),
+ *   base_table = "entity_test",
+ *   entity_keys = {
+ *     "id" = "id",
+ *     "bundle" = "type"
+ *   }
+ * )
+ */
+class EntityTestDefaultAccess extends EntityTest {
+
+}

core/modules/system/tests/modules/entity_test/src/Entity/EntityTestDefaultValue.php

@@ -0,0 +1,43 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\entity_test\Entity\EntityTestDefaultValue.
+ */
+
+namespace Drupal\entity_test\Entity;
+
+use Drupal\Core\Entity\EntityTypeInterface;
+use Drupal\Core\Field\BaseFieldDefinition;
+
+/**
+ * Defines a test entity class for testing default values.
+ *
+ * @ContentEntityType(
+ *   id = "entity_test_default_value",
+ *   label = @Translation("Test entity for default values"),
+ *   base_table = "entity_test_default_value",
+ *   entity_keys = {
+ *     "id" = "id",
+ *     "uuid" = "uuid",
+ *     "bundle" = "type",
+ *     "langcode" = "langcode"
+ *   }
+ * )
+ */
+class EntityTestDefaultValue extends EntityTest {
+
+  /**
+   * {@inheritdoc}
+   */
+  public static function baseFieldDefinitions(EntityTypeInterface $entity_type) {
+    $fields = parent::baseFieldDefinitions($entity_type);
+
+    $fields['description'] = BaseFieldDefinition::create('shape')
+      ->setLabel(t('Some custom description'))
+      ->setDefaultValueCallback('entity_test_field_default_value');
+
+    return $fields;
+  }
+
+}

core/modules/system/tests/modules/entity_test/src/Entity/EntityTestFieldOverride.php

@@ -0,0 +1,49 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\entity_test\Entity\EntityTestFieldOverride.
+ */
+
+namespace Drupal\entity_test\Entity;
+
+use Drupal\Core\Entity\EntityTypeInterface;
+
+/**
+ * Defines a test entity class for testing default values.
+ *
+ * @ContentEntityType(
+ *   id = "entity_test_field_override",
+ *   label = @Translation("Test entity field overrides"),
+ *   base_table = "entity_test_field_override",
+ *   entity_keys = {
+ *     "id" = "id",
+ *     "uuid" = "uuid",
+ *     "bundle" = "type"
+ *   }
+ * )
+ */
+class EntityTestFieldOverride extends EntityTest {
+
+  /**
+   * {@inheritdoc}
+   */
+  public static function baseFieldDefinitions(EntityTypeInterface $entity_type) {
+    $fields = parent::baseFieldDefinitions($entity_type);
+    $fields['name']->setDescription('The default description.');
+    return $fields;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public static function bundleFieldDefinitions(EntityTypeInterface $entity_type, $bundle, array $base_field_definitions) {
+    $fields = parent::bundleFieldDefinitions($entity_type, $bundle, $base_field_definitions);
+
+    if ($bundle == 'some_test_bundle') {
+      $fields['name'] = clone $base_field_definitions['name'];
+      $fields['name']->setDescription('Custom description.');
+    }
+    return $fields;
+  }
+}

core/modules/system/tests/modules/entity_test/src/Entity/EntityTestLabel.php

@@ -0,0 +1,31 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\entity_test\Entity\EntityTestLabel.
+ */
+
+namespace Drupal\entity_test\Entity;
+
+/**
+ * Test entity class.
+ *
+ * @ContentEntityType(
+ *   id = "entity_test_label",
+ *   label = @Translation("Entity Test label"),
+ *   handlers = {
+ *     "access" = "Drupal\entity_test\EntityTestAccessControlHandler",
+ *     "view_builder" = "Drupal\entity_test\EntityTestViewBuilder"
+ *   },
+ *   base_table = "entity_test",
+ *   render_cache = FALSE,
+ *   entity_keys = {
+ *     "id" = "id",
+ *     "label" = "name",
+ *     "bundle" = "type"
+ *   }
+ * )
+ */
+class EntityTestLabel extends EntityTest {
+
+}

core/modules/system/tests/modules/entity_test/src/Entity/EntityTestLabelCallback.php

@@ -0,0 +1,27 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\entity_test\Entity\EntityTestLabelCallback.
+ */
+
+namespace Drupal\entity_test\Entity;
+
+/**
+ * Test entity class.
+ *
+ * @ContentEntityType(
+ *   id = "entity_test_label_callback",
+ *   label = @Translation("Entity test label callback"),
+ *   persistent_cache = FALSE,
+ *   base_table = "entity_test",
+ *   label_callback = "entity_test_label_callback",
+ *   entity_keys = {
+ *     "id" = "id",
+ *     "bundle" = "type"
+ *   }
+ * )
+ */
+class EntityTestLabelCallback extends EntityTest {
+
+}

core/modules/system/tests/modules/entity_test/src/Entity/EntityTestMul.php

@@ -0,0 +1,50 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\entity_test\Entity\EntityTestMul.
+ */
+
+namespace Drupal\entity_test\Entity;
+
+use Drupal\Core\Entity\EntityTypeInterface;
+use Drupal\Core\Field\BaseFieldDefinition;
+use Drupal\entity_test\Entity\EntityTest;
+
+/**
+ * Defines the test entity class.
+ *
+ * @ContentEntityType(
+ *   id = "entity_test_mul",
+ *   label = @Translation("Test entity - data table"),
+ *   handlers = {
+ *     "view_builder" = "Drupal\entity_test\EntityTestViewBuilder",
+ *     "access" = "Drupal\entity_test\EntityTestAccessControlHandler",
+ *     "form" = {
+ *       "default" = "Drupal\entity_test\EntityTestForm",
+ *       "delete" = "Drupal\entity_test\EntityTestDeleteForm"
+ *     },
+ *     "translation" = "Drupal\content_translation\ContentTranslationHandler",
+ *     "views_data" = "Drupal\views\EntityViewsData"
+ *   },
+ *   base_table = "entity_test_mul",
+ *   data_table = "entity_test_mul_property_data",
+ *   translatable = TRUE,
+ *   entity_keys = {
+ *     "id" = "id",
+ *     "uuid" = "uuid",
+ *     "bundle" = "type",
+ *     "label" = "name",
+ *     "langcode" = "langcode",
+ *   },
+ *   links = {
+ *     "canonical" = "/entity_test_mul/manage/{entity_test_mul}",
+ *     "edit-form" = "/entity_test_mul/manage/{entity_test_mul}",
+ *     "delete-form" = "/entity_test/delete/entity_test_mul/{entity_test_mul}",
+ *   },
+ *   field_ui_base_route = "entity.entity_test_mul.admin_form",
+ * )
+ */
+class EntityTestMul extends EntityTest {
+
+}

core/modules/system/tests/modules/entity_test/src/Entity/EntityTestMulChanged.php

@@ -0,0 +1,83 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\entity_test\Entity\EntityTestMulChanged.
+ */
+
+namespace Drupal\entity_test\Entity;
+
+use Drupal\Core\Entity\EntityChangedInterface;
+use Drupal\Core\Entity\EntityChangedTrait;
+use Drupal\Core\Entity\EntityTypeInterface;
+use Drupal\Core\Field\BaseFieldDefinition;
+
+/**
+ * Defines the test entity class.
+ *
+ * @ContentEntityType(
+ *   id = "entity_test_mul_changed",
+ *   label = @Translation("Test entity - data table"),
+ *   handlers = {
+ *     "view_builder" = "Drupal\entity_test\EntityTestViewBuilder",
+ *     "access" = "Drupal\entity_test\EntityTestAccessControlHandler",
+ *     "form" = {
+ *       "default" = "Drupal\entity_test\EntityTestForm",
+ *       "delete" = "Drupal\entity_test\EntityTestDeleteForm"
+ *     },
+ *     "translation" = "Drupal\content_translation\ContentTranslationHandler",
+ *     "views_data" = "Drupal\views\EntityViewsData"
+ *   },
+ *   base_table = "entity_test_mul_changed",
+ *   data_table = "entity_test_mul_changed_property",
+ *   translatable = TRUE,
+ *   entity_keys = {
+ *     "id" = "id",
+ *     "uuid" = "uuid",
+ *     "bundle" = "type",
+ *     "label" = "name",
+ *     "langcode" = "langcode"
+ *   },
+ *   links = {
+ *     "canonical" = "/entity_test_mul_changed/manage/{entity_test_mul_changed}",
+ *     "edit-form" = "/entity_test_mul_changed/manage/{entity_test_mul_changed}",
+ *     "delete-form" = "/entity_test/delete/entity_test_mul_changed/{entity_test_mul_changed}",
+ *   },
+ *   field_ui_base_route = "entity.entity_test_mul_changed.admin_form",
+ * )
+ */
+class EntityTestMulChanged extends EntityTestMul implements EntityChangedInterface {
+
+  use EntityChangedTrait;
+
+  /**
+   * {@inheritdoc}
+   */
+  public static function baseFieldDefinitions(EntityTypeInterface $entity_type) {
+    $fields = parent::baseFieldDefinitions($entity_type);
+
+    $fields['changed'] = BaseFieldDefinition::create('changed_test')
+      ->setLabel(t('Changed'))
+      ->setDescription(t('The time that the entity was last edited.'))
+      ->setTranslatable(TRUE);
+
+    return $fields;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function save() {
+    // Ensure a new timestamp.
+    sleep(1);
+    parent::save();
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function getChangedTime() {
+    return $this->get('changed')->value;
+  }
+
+}

core/modules/system/tests/modules/entity_test/src/Entity/EntityTestMulDefaultValue.php

@@ -0,0 +1,63 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\entity_test\Entity\EntityTestMulDefaultValue.
+ */
+
+namespace Drupal\entity_test\Entity;
+
+use Drupal\Core\Entity\EntityTypeInterface;
+use Drupal\Core\Field\BaseFieldDefinition;
+
+/**
+ * Defines the test entity class.
+ *
+ * @ContentEntityType(
+ *   id = "entity_test_mul_default_value",
+ *   label = @Translation("Test entity - data table"),
+ *   handlers = {
+ *     "view_builder" = "Drupal\entity_test\EntityTestViewBuilder",
+ *     "access" = "Drupal\entity_test\EntityTestAccessControlHandler",
+ *     "form" = {
+ *       "default" = "Drupal\entity_test\EntityTestForm",
+ *       "delete" = "Drupal\entity_test\EntityTestDeleteForm"
+ *     },
+ *     "translation" = "Drupal\content_translation\ContentTranslationHandler",
+ *     "views_data" = "Drupal\views\EntityViewsData"
+ *   },
+ *   base_table = "entity_test_mul_default_value",
+ *   data_table = "entity_test_mul_default_value_property_data",
+ *   translatable = TRUE,
+ *   entity_keys = {
+ *     "id" = "id",
+ *     "uuid" = "uuid",
+ *     "bundle" = "type",
+ *     "label" = "name",
+ *     "langcode" = "langcode"
+ *   },
+ *   links = {
+ *     "canonical" = "/entity_test_mul_default_value/manage/{entity_test_mul_default_value}",
+ *     "edit-form" = "/entity_test_mul_default_value/manage/{entity_test_mul_default_value}",
+ *     "delete-form" = "/entity_test/delete/entity_test_mul_default_value/{entity_test_mul_default_value}",
+ *   },
+ *   field_ui_base_route = "entity.entity_test_mul.admin_form",
+ * )
+ */
+class EntityTestMulDefaultValue extends EntityTestMul {
+
+  /**
+   * {@inheritdoc}
+   */
+  public static function baseFieldDefinitions(EntityTypeInterface $entity_type) {
+    $fields = parent::baseFieldDefinitions($entity_type);
+
+    $fields['description'] = BaseFieldDefinition::create('shape')
+      ->setLabel(t('Some custom description'))
+      ->setTranslatable(TRUE)
+      ->setDefaultValueCallback('entity_test_field_default_value');
+
+    return $fields;
+  }
+
+}

core/modules/system/tests/modules/entity_test/src/Entity/EntityTestMulLangcodeKey.php

@@ -0,0 +1,59 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\entity_test\Entity\EntityTestMulLangcodeKey.
+ */
+
+namespace Drupal\entity_test\Entity;
+
+use Drupal\Core\Entity\EntityTypeInterface;
+
+/**
+ * Defines a test entity class using a custom langcode entity key.
+ *
+ * @ContentEntityType(
+ *   id = "entity_test_mul_langcode_key",
+ *   label = @Translation("Test entity - data table - langcode key"),
+ *   handlers = {
+ *     "view_builder" = "Drupal\entity_test\EntityTestViewBuilder",
+ *     "access" = "Drupal\entity_test\EntityTestAccessControlHandler",
+ *     "form" = {
+ *       "default" = "Drupal\entity_test\EntityTestForm",
+ *       "delete" = "Drupal\entity_test\EntityTestDeleteForm"
+ *     },
+ *     "translation" = "Drupal\content_translation\ContentTranslationHandler",
+ *     "views_data" = "Drupal\views\EntityViewsData"
+ *   },
+ *   base_table = "entity_test_mul_langcode_key",
+ *   data_table = "entity_test_mul_langcode_key_field_data",
+ *   translatable = TRUE,
+ *   entity_keys = {
+ *     "id" = "id",
+ *     "uuid" = "uuid",
+ *     "bundle" = "type",
+ *     "label" = "name",
+ *     "langcode" = "custom_langcode_key",
+ *     "default_langcode" = "custom_default_langcode_key",
+ *   },
+ *   links = {
+ *     "canonical" = "/entity_test_mul_langcode_key/manage/{entity_test_mul_langcode_key}",
+ *     "edit-form" = "/entity_test_mul_langcode_key/manage/{entity_test_mul_langcode_key}",
+ *     "delete-form" = "/entity_test/delete/entity_test_mul_langcode_key/{entity_test_mul_langcode_key}",
+ *   },
+ *   field_ui_base_route = "entity.entity_test_mul_langcode_key.admin_form",
+ * )
+ */
+class EntityTestMulLangcodeKey extends EntityTest {
+
+  /**
+   * {@inheritdoc}
+   */
+  public static function baseFieldDefinitions(EntityTypeInterface $entity_type) {
+    $fields = parent::baseFieldDefinitions($entity_type);
+    $fields['custom_langcode_key'] = $fields['langcode'];
+    unset($fields['langcode']);
+    return $fields;
+  }
+
+}

core/modules/system/tests/modules/entity_test/src/Entity/EntityTestMulRev.php

@@ -0,0 +1,53 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\entity_test\Entity\EntityTestMulRev.
+ */
+
+namespace Drupal\entity_test\Entity;
+
+use Drupal\Core\Entity\EntityTypeInterface;
+use Drupal\Core\Field\BaseFieldDefinition;
+use Drupal\entity_test\Entity\EntityTestRev;
+
+/**
+ * Defines the test entity class.
+ *
+ * @ContentEntityType(
+ *   id = "entity_test_mulrev",
+ *   label = @Translation("Test entity - revisions and data table"),
+ *   handlers = {
+ *     "view_builder" = "Drupal\entity_test\EntityTestViewBuilder",
+ *     "access" = "Drupal\entity_test\EntityTestAccessControlHandler",
+ *     "form" = {
+ *       "default" = "Drupal\entity_test\EntityTestForm",
+ *       "delete" = "Drupal\entity_test\EntityTestDeleteForm"
+ *     },
+ *     "translation" = "Drupal\content_translation\ContentTranslationHandler",
+ *     "views_data" = "Drupal\views\EntityViewsData"
+ *   },
+ *   base_table = "entity_test_mulrev",
+ *   data_table = "entity_test_mulrev_property_data",
+ *   revision_table = "entity_test_mulrev_revision",
+ *   revision_data_table = "entity_test_mulrev_property_revision",
+ *   translatable = TRUE,
+ *   entity_keys = {
+ *     "id" = "id",
+ *     "uuid" = "uuid",
+ *     "bundle" = "type",
+ *     "revision" = "revision_id",
+ *     "label" = "name",
+ *     "langcode" = "langcode",
+ *   },
+ *   links = {
+ *     "canonical" = "/entity_test_mulrev/manage/{entity_test_mulrev}",
+ *     "delete-form" = "/entity_test/delete/entity_test_mulrev/{entity_test_mulrev}",
+ *     "edit-form" = "/entity_test_mulrev/manage/{entity_test_mulrev}",
+ *     "revision" = "/entity_test_mulrev/{entity_test_mulrev}/revision/{entity_test_mulrev_revision}/view",
+ *   }
+ * )
+ */
+class EntityTestMulRev extends EntityTestRev {
+
+}

core/modules/system/tests/modules/entity_test/src/Entity/EntityTestMulRevChanged.php

@@ -0,0 +1,79 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\entity_test\Entity\EntityTestMulRevChanged.
+ */
+
+namespace Drupal\entity_test\Entity;
+
+use Drupal\Core\Entity\EntityTypeInterface;
+use Drupal\Core\Field\BaseFieldDefinition;
+
+/**
+ * Defines the test entity class.
+ *
+ * @ContentEntityType(
+ *   id = "entity_test_mulrev_changed",
+ *   label = @Translation("Test entity - revisions and data table"),
+ *   handlers = {
+ *     "view_builder" = "Drupal\entity_test\EntityTestViewBuilder",
+ *     "access" = "Drupal\entity_test\EntityTestAccessControlHandler",
+ *     "form" = {
+ *       "default" = "Drupal\entity_test\EntityTestForm",
+ *       "delete" = "Drupal\entity_test\EntityTestDeleteForm"
+ *     },
+ *     "translation" = "Drupal\content_translation\ContentTranslationHandler",
+ *     "views_data" = "Drupal\views\EntityViewsData"
+ *   },
+ *   base_table = "entity_test_mulrev_changed",
+ *   data_table = "entity_test_mulrev_changed_property",
+ *   revision_table = "entity_test_mulrev_changed_revision",
+ *   revision_data_table = "entity_test_mulrev_changed_property_revision",
+ *   translatable = TRUE,
+ *   entity_keys = {
+ *     "id" = "id",
+ *     "uuid" = "uuid",
+ *     "bundle" = "type",
+ *     "revision" = "revision_id",
+ *     "label" = "name",
+ *     "langcode" = "langcode",
+ *   },
+ *   links = {
+ *     "canonical" = "/entity_test_mulrev_changed/manage/{entity_test_mulrev_changed}",
+ *     "delete-form" = "/entity_test/delete/entity_test_mulrev_changed/{entity_test_mulrev_changed}",
+ *     "edit-form" = "/entity_test_mulrev_changed/manage/{entity_test_mulrev_changed}",
+ *     "revision" = "/entity_test_mulrev_changed/{entity_test_mulrev_changed}/revision/{entity_test_mulrev_changed_revision}/view",
+ *   }
+ * )
+ */
+class EntityTestMulRevChanged extends EntityTestMulChanged {
+
+  /**
+   * {@inheritdoc}
+   */
+  public static function baseFieldDefinitions(EntityTypeInterface $entity_type) {
+    $fields = parent::baseFieldDefinitions($entity_type);
+
+    $fields['revision_id'] = BaseFieldDefinition::create('integer')
+      ->setLabel(t('Revision ID'))
+      ->setDescription(t('The version id of the test entity.'))
+      ->setReadOnly(TRUE)
+      ->setSetting('unsigned', TRUE);
+
+    $fields['revision_translation_affected'] = BaseFieldDefinition::create('boolean')
+      ->setLabel(t('Revision translation affected'))
+      ->setDescription(t('Indicates if the last edit of a translation belongs to current revision.'))
+      ->setReadOnly(TRUE)
+      ->setRevisionable(TRUE)
+      ->setTranslatable(TRUE);
+
+    $fields['langcode']->setRevisionable(TRUE);
+    $fields['name']->setRevisionable(TRUE);
+    $fields['user_id']->setRevisionable(TRUE);
+    $fields['changed']->setRevisionable(TRUE);
+
+    return $fields;
+  }
+
+}

core/modules/system/tests/modules/entity_test/src/Entity/EntityTestNew.php

@@ -0,0 +1,30 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\entity_test\Entity\EntityTestNew.
+ */
+
+namespace Drupal\entity_test\Entity;
+
+/**
+ * Defines the test entity class for testing definition addition.
+ *
+ * This entity type is initially not defined. It is enabled when needed to test
+ * the related updates.
+ *
+ * @ContentEntityType(
+ *   id = "entity_test_new",
+ *   label = @Translation("New test entity"),
+ *   base_table = "entity_test_new",
+ *   entity_keys = {
+ *     "id" = "id",
+ *     "uuid" = "uuid",
+ *     "bundle" = "type",
+ *     "label" = "name",
+ *     "langcode" = "langcode",
+ *   }
+ * )
+ */
+class EntityTestNew extends EntityTest {
+}