Issue #2484991 by znerol, voleger, andypost, dww, anmolgoyal74, markdorison, ankithashetty, larowlan, daffie, alexpott: Add the session to the request in KernelTestBase, BrowserTestBase, and drush

core/lib/Drupal/Core/DrupalKernel.php

@@ -28,6 +28,8 @@ use Symfony\Component\DependencyInjection\ParameterBag\ParameterBag;
 use Symfony\Component\HttpFoundation\RedirectResponse;
 use Symfony\Component\HttpFoundation\Request;
 use Symfony\Component\HttpFoundation\Response;
+use Symfony\Component\HttpFoundation\Session\Session;
+use Symfony\Component\HttpFoundation\Session\Storage\MockArraySessionStorage;
 use Symfony\Component\HttpKernel\Exception\BadRequestHttpException;
 use Symfony\Component\HttpKernel\Exception\HttpExceptionInterface;
 use Symfony\Component\HttpKernel\TerminableInterface;
@@ -582,6 +584,11 @@ class DrupalKernel implements DrupalKernelInterface, TerminableInterface {
       (bool) Settings::get(RequestSanitizer::SANITIZE_LOG, FALSE)
     );
 
+    // Ensure that there is a session on every request.
+    if (!$request->hasSession()) {
+      $this->initializeEphemeralSession($request);
+    }
+
     $this->loadLegacyIncludes();
 
     // Load all enabled modules.
@@ -1638,4 +1645,23 @@ class DrupalKernel implements DrupalKernelInterface, TerminableInterface {
     return $config['profile'] ?? NULL;
   }
 
+  /**
+   * Initializes a session backed by in-memory store and puts it on the request.
+   *
+   * A simple in-memory store is sufficient for command line tools and tests.
+   * Web requests will be processed by the session middleware where the mock
+   * session is replaced by a session object backed with persistent storage and
+   * a real session handler.
+   *
+   * @param \Symfony\Component\HttpFoundation\Request $request
+   *   The request.
+   *
+   * @see \Drupal\Core\StackMiddleware\Session::handle()
+   */
+  protected function initializeEphemeralSession(Request $request): void {
+    $session = new Session(new MockArraySessionStorage());
+    $session->start();
+    $request->setSession($session);
+  }
+
 }

core/lib/Drupal/Core/StackMiddleware/Session.php

@@ -49,19 +49,42 @@ class Session implements HttpKernelInterface {
    * {@inheritdoc}
    */
   public function handle(Request $request, $type = self::MAIN_REQUEST, $catch = TRUE): Response {
+    // Initialize and start a session for web requests. Command line tools and
+    // the parent site in functional tests must continue to use the ephemeral
+    // session initialized and started in DrupalKernel::preHandle().
     if ($type === self::MAIN_REQUEST && PHP_SAPI !== 'cli') {
-      $session = $this->container->get($this->sessionServiceName);
-      $session->start();
-      $request->setSession($session);
+      $this->initializePersistentSession($request);
     }
 
     $result = $this->httpKernel->handle($request, $type, $catch);
 
-    if ($type === self::MAIN_REQUEST && $request->hasSession()) {
+    if ($type === self::MAIN_REQUEST && PHP_SAPI !== 'cli' && $request->hasSession()) {
       $request->getSession()->save();
     }
 
     return $result;
   }
 
+  /**
+   * Initializes a session backed by persistent store and puts it on the request.
+   *
+   * Sessions for web requests need to be backed by a persistent session store
+   * and a real session handler (responsible for session cookie management).
+   * In contrast, a simple in-memory store is sufficient for command line tools
+   * and tests. Hence, the persistent session should only ever be placed on web
+   * requests while command line tools and the parent site in functional tests
+   * must continue to use the ephemeral session initialized in
+   * DrupalKernel::preHandle().
+   *
+   * @param \Symfony\Component\HttpFoundation\Request $request
+   *   The request.
+   *
+   * @see \Drupal\Core\DrupalKernel::preHandle()
+   */
+  protected function initializePersistentSession(Request $request): void {
+    $session = $this->container->get($this->sessionServiceName);
+    $session->start();
+    $request->setSession($session);
+  }
+
 }

core/lib/Drupal/Core/Test/FunctionalTestSetupTrait.php

@@ -23,6 +23,8 @@ use Symfony\Component\DependencyInjection\ContainerInterface;
 use Symfony\Component\HttpFoundation\Request;
 use Symfony\Component\Yaml\Yaml as SymfonyYaml;
 use Drupal\Core\Routing\RouteObjectInterface;
+use Symfony\Component\HttpFoundation\Session\Session;
+use Symfony\Component\HttpFoundation\Session\Storage\MockArraySessionStorage;
 use Symfony\Component\Routing\Route;
 
 /**
@@ -210,10 +212,6 @@ trait FunctionalTestSetupTrait {
   protected function rebuildContainer() {
     // Rebuild the kernel and bring it back to a fully bootstrapped state.
     $this->container = $this->kernel->rebuildContainer();
-
-    // Make sure the URL generator has a request object, otherwise calls to
-    // $this->drupalGet() will fail.
-    $this->prepareRequestForGenerator();
   }
 
   /**
@@ -254,6 +252,7 @@ trait FunctionalTestSetupTrait {
    */
   protected function prepareRequestForGenerator($clean_urls = TRUE, $override_server_vars = []) {
     $request = Request::createFromGlobals();
+    $request->setSession(new Session(new MockArraySessionStorage()));
     $base_path = $request->getBasePath();
     if ($clean_urls) {
       $request_path = $base_path ? $base_path . '/user' : 'user';
@@ -265,6 +264,7 @@ trait FunctionalTestSetupTrait {
     $server = array_merge($request->server->all(), $override_server_vars);
 
     $request = Request::create($request_path, 'GET', [], [], [], $server);
+    $request->setSession(new Session(new MockArraySessionStorage()));
     // Ensure the request time is REQUEST_TIME to ensure that API calls
     // in the test use the right timestamp.
     $request->server->set('REQUEST_TIME', REQUEST_TIME);

core/modules/book/tests/src/Kernel/BookMultilingualTest.php

@@ -14,6 +14,8 @@ use Drupal\node\Entity\NodeType;
 use Drupal\Tests\user\Traits\UserCreationTrait;
 use Drupal\user\Plugin\LanguageNegotiation\LanguageNegotiationUser;
 use Symfony\Component\HttpFoundation\Request;
+use Symfony\Component\HttpFoundation\Session\Session;
+use Symfony\Component\HttpFoundation\Session\Storage\MockArraySessionStorage;
 use Symfony\Component\Routing\Route;
 
 /**
@@ -271,7 +273,9 @@ class BookMultilingualTest extends KernelTestBase {
    *   is used instead of the content language.
    */
   protected function setCurrentLanguage(string $langcode): void {
-    \Drupal::requestStack()->push(Request::create("http://$langcode.book.test.domain/"));
+    $request = Request::create("http://$langcode.book.test.domain/");
+    $request->setSession(new Session(new MockArraySessionStorage()));
+    \Drupal::requestStack()->push($request);
     $language_manager = $this->container->get('language_manager');
     $language_manager->reset();
     $current_user = \Drupal::currentUser();

core/modules/comment/tests/src/Kernel/CommentHostnameTest.php

@@ -6,6 +6,8 @@ use Drupal\comment\Entity\Comment;
 use Drupal\comment\Entity\CommentType;
 use Drupal\KernelTests\KernelTestBase;
 use Symfony\Component\HttpFoundation\Request;
+use Symfony\Component\HttpFoundation\Session\Session;
+use Symfony\Component\HttpFoundation\Session\Storage\MockArraySessionStorage;
 
 /**
  * Tests the hostname base field.
@@ -29,6 +31,7 @@ class CommentHostnameTest extends KernelTestBase {
   public function testGetDefaultHostname() {
     // Create a fake request to be used for testing.
     $request = Request::create('/', 'GET', [], [], [], ['REMOTE_ADDR' => '203.0.113.1']);
+    $request->setSession(new Session(new MockArraySessionStorage()));
     /** @var \Symfony\Component\HttpFoundation\RequestStack $stack */
     $stack = $this->container->get('request_stack');
     $stack->push($request);

core/modules/file/tests/src/Kernel/RequirementsTest.php

@@ -7,6 +7,8 @@ namespace Drupal\Tests\file\Kernel;
 use Drupal\KernelTests\KernelTestBase;
 use Symfony\Component\HttpFoundation\Request;
 use Symfony\Component\HttpFoundation\RequestStack;
+use Symfony\Component\HttpFoundation\Session\Session;
+use Symfony\Component\HttpFoundation\Session\Storage\MockArraySessionStorage;
 
 /**
  * Tests the file requirements.
@@ -69,6 +71,7 @@ class RequirementsTest extends KernelTestBase {
    */
   private function setServerSoftware(?string $software): void {
     $request = new Request();
+    $request->setSession(new Session(new MockArraySessionStorage()));
     if (is_string($software)) {
       $request->server->set('SERVER_SOFTWARE', $software);
     }

core/modules/language/tests/src/Functional/LanguageNegotiationContentEntityTest.php

@@ -10,6 +10,8 @@ use Drupal\language\Plugin\LanguageNegotiation\LanguageNegotiationUrl;
 use Drupal\Tests\BrowserTestBase;
 use Drupal\Core\Routing\RouteObjectInterface;
 use Symfony\Component\HttpFoundation\Request;
+use Symfony\Component\HttpFoundation\Session\Session;
+use Symfony\Component\HttpFoundation\Session\Storage\MockArraySessionStorage;
 use Symfony\Component\Routing\Route;
 
 /**
@@ -185,6 +187,7 @@ class LanguageNegotiationContentEntityTest extends BrowserTestBase {
     $request = Request::create($path);
     $request->attributes->set(RouteObjectInterface::ROUTE_NAME, $route_name);
     $request->attributes->set(RouteObjectInterface::ROUTE_OBJECT, new Route($path));
+    $request->setSession(new Session(new MockArraySessionStorage()));
     $this->container->get('request_stack')->push($request);
   }
 

core/modules/language/tests/src/Functional/LanguageUILanguageNegotiationTest.php

@@ -19,6 +19,8 @@ use Drupal\Core\Language\LanguageInterface;
 use Symfony\Component\HttpFoundation\Request;
 use Drupal\language\LanguageNegotiatorInterface;
 use Drupal\block\Entity\Block;
+use Symfony\Component\HttpFoundation\Session\Session;
+use Symfony\Component\HttpFoundation\Session\Storage\MockArraySessionStorage;
 
 /**
  * Tests the language UI for language switching.
@@ -564,6 +566,7 @@ class LanguageUILanguageNegotiationTest extends BrowserTestBase {
 
     // Test HTTPS via current URL scheme.
     $request = Request::create('', 'GET', [], [], [], ['HTTPS' => 'on']);
+    $request->setSession(new Session(new MockArraySessionStorage()));
     $this->container->get('request_stack')->push($request);
     $italian_url = Url::fromRoute('system.admin', [], ['language' => $languages['it']])->toString();
     $correct_link = 'https://' . $link;

core/modules/language/tests/src/Kernel/EntityUrlLanguageTest.php

@@ -9,6 +9,8 @@ use Drupal\language\Plugin\LanguageNegotiation\LanguageNegotiationContentEntity;
 use Drupal\language\Plugin\LanguageNegotiation\LanguageNegotiationUrl;
 use Drupal\Core\Routing\RouteObjectInterface;
 use Symfony\Component\HttpFoundation\Request;
+use Symfony\Component\HttpFoundation\Session\Session;
+use Symfony\Component\HttpFoundation\Session\Storage\MockArraySessionStorage;
 use Symfony\Component\Routing\Route;
 
 /**
@@ -132,6 +134,7 @@ class EntityUrlLanguageTest extends LanguageTestBase {
     $request = Request::create($path);
     $request->attributes->set(RouteObjectInterface::ROUTE_NAME, $route_name);
     $request->attributes->set(RouteObjectInterface::ROUTE_OBJECT, new Route($path));
+    $request->setSession(new Session(new MockArraySessionStorage()));
     $this->container->get('request_stack')->push($request);
   }
 

core/modules/menu_link_content/tests/src/Kernel/MenuLinkContentCacheabilityBubblingTest.php

@@ -12,6 +12,8 @@ use Drupal\Tests\user\Traits\UserCreationTrait;
 use Drupal\user\Entity\User;
 use Drupal\Core\Routing\RouteObjectInterface;
 use Symfony\Component\HttpFoundation\Request;
+use Symfony\Component\HttpFoundation\Session\Session;
+use Symfony\Component\HttpFoundation\Session\Storage\MockArraySessionStorage;
 use Symfony\Component\Routing\Route;
 
 /**
@@ -62,6 +64,7 @@ class MenuLinkContentCacheabilityBubblingTest extends KernelTestBase {
     $request = Request::create('/');
     $request->attributes->set(RouteObjectInterface::ROUTE_NAME, '<front>');
     $request->attributes->set(RouteObjectInterface::ROUTE_OBJECT, new Route('/'));
+    $request->setSession(new Session(new MockArraySessionStorage()));
     $request_stack->push($request);
     $request_context->fromRequest($request);
 

core/modules/rest/tests/src/Functional/Views/StyleSerializerTest.php

@@ -16,6 +16,8 @@ use Drupal\views\Entity\View;
 use Drupal\views\Plugin\views\display\DisplayPluginBase;
 use Drupal\views\Views;
 use Symfony\Component\HttpFoundation\Request;
+use Symfony\Component\HttpFoundation\Session\Session;
+use Symfony\Component\HttpFoundation\Session\Storage\MockArraySessionStorage;
 
 /**
  * Tests the serializer style plugin.
@@ -594,6 +596,7 @@ class StyleSerializerTest extends ViewTestBase {
     // We set up a request so it looks like a request in the live preview.
     $request = new Request();
     $request->query->add([MainContentViewSubscriber::WRAPPER_FORMAT => 'drupal_ajax']);
+    $request->setSession(new Session(new MockArraySessionStorage()));
     /** @var \Symfony\Component\HttpFoundation\RequestStack $request_stack */
     $request_stack = \Drupal::service('request_stack');
     $request_stack->push($request);

core/modules/syslog/tests/src/Kernel/SyslogTest.php

@@ -4,6 +4,8 @@ namespace Drupal\Tests\syslog\Kernel;
 
 use Drupal\KernelTests\KernelTestBase;
 use Symfony\Component\HttpFoundation\Request;
+use Symfony\Component\HttpFoundation\Session\Session;
+use Symfony\Component\HttpFoundation\Session\Storage\MockArraySessionStorage;
 
 /**
  * Test syslog logger functionality.
@@ -30,6 +32,7 @@ class SyslogTest extends KernelTestBase {
 
     $request = Request::create('/page-not-found', 'GET', [], [], [], ['REMOTE_ADDR' => '1.2.3.4']);
     $request->headers->set('Referer', 'other-site');
+    $request->setSession(new Session(new MockArraySessionStorage()));
     \Drupal::requestStack()->push($request);
 
     $user = $this->getMockBuilder('Drupal\Core\Session\AccountInterface')->getMock();

core/modules/system/tests/src/Functional/Database/SelectPagerDefaultTest.php

@@ -6,6 +6,8 @@ use Drupal\Component\Render\FormattableMarkup;
 use Drupal\Core\Database\Database;
 use Drupal\Core\Database\Query\PagerSelectExtender;
 use Symfony\Component\HttpFoundation\Request;
+use Symfony\Component\HttpFoundation\Session\Session;
+use Symfony\Component\HttpFoundation\Session\Storage\MockArraySessionStorage;
 
 /**
  * Tests the pager query select extender.
@@ -141,6 +143,7 @@ class SelectPagerDefaultTest extends DatabaseTestBase {
     $request->query->replace([
       'page' => '3, 2, 1, 0',
     ]);
+    $request->setSession(new Session(new MockArraySessionStorage()));
     \Drupal::getContainer()->get('request_stack')->push($request);
 
     $connection = Database::getConnection();

core/modules/system/tests/src/Kernel/Block/SystemMenuBlockTest.php

@@ -11,6 +11,8 @@ use Drupal\Tests\Core\Menu\MenuLinkMock;
 use Drupal\user\Entity\User;
 use Drupal\Core\Routing\RouteObjectInterface;
 use Symfony\Component\HttpFoundation\Request;
+use Symfony\Component\HttpFoundation\Session\Session;
+use Symfony\Component\HttpFoundation\Session\Storage\MockArraySessionStorage;
 use Symfony\Component\Routing\Route;
 use Symfony\Component\Routing\RouteCollection;
 
@@ -233,6 +235,7 @@ class SystemMenuBlockTest extends KernelTestBase {
     $request = new Request();
     $request->attributes->set(RouteObjectInterface::ROUTE_NAME, 'example3');
     $request->attributes->set(RouteObjectInterface::ROUTE_OBJECT, $route);
+    $request->setSession(new Session(new MockArraySessionStorage()));
     $this->container->get('request_stack')->push($request);
     // \Drupal\Core\Menu\MenuActiveTrail uses the cache collector pattern, which
     // includes static caching. Since this second scenario simulates a second
@@ -300,6 +303,7 @@ class SystemMenuBlockTest extends KernelTestBase {
     $request = new Request();
     $request->attributes->set(RouteObjectInterface::ROUTE_NAME, $active_route);
     $request->attributes->set(RouteObjectInterface::ROUTE_OBJECT, $route);
+    $request->setSession(new Session(new MockArraySessionStorage()));
     $this->container->get('request_stack')->push($request);
 
     $block_build = $block->build();

core/modules/system/tests/src/Kernel/Theme/TwigIncludeTest.php

@@ -68,8 +68,10 @@ class TwigIncludeTest extends KernelTestBase {
     $twig_config = $this->container->getParameter('twig.config');
     $twig_config['allowed_file_extensions'][] = 'sql';
     $this->twigConfig = $twig_config;
-    $this->container->get('kernel')->shutdown();
-    $this->container->get('kernel')->boot();
+    // @todo This used to call shutdown() and boot(). rebuildContainer() is
+    // needed until we stop pushing the request twice and only popping it once.
+    // @see https://www.drupal.org/i/2613044
+    $this->container->get('kernel')->rebuildContainer();
     /** @var \Drupal\Core\Template\Loader\FilesystemLoader $loader */
     $loader = \Drupal::service('twig.loader.filesystem');
     $source = $loader->getSourceContext('@__main__\/core/tests/fixtures/files/sql-2.sql');
@@ -80,8 +82,10 @@ class TwigIncludeTest extends KernelTestBase {
     $this->assertSame(['css', 'html', 'js', 'svg', 'twig', 'sql'], \Drupal::getContainer()->getParameter('twig.config')['allowed_file_extensions']);
     unset($twig_config['allowed_file_extensions']);
     $this->twigConfig = $twig_config;
-    $this->container->get('kernel')->shutdown();
-    $this->container->get('kernel')->boot();
+    // @todo This used to call shutdown() and boot(). rebuildContainer() is
+    // needed until we stop pushing the request twice and only popping it once.
+    // @see https://www.drupal.org/i/2613044
+    $this->container->get('kernel')->rebuildContainer();
     $this->assertArrayNotHasKey('allowed_file_extensions', \Drupal::getContainer()->getParameter('twig.config'));
     /** @var \Drupal\Core\Template\Loader\FilesystemLoader $loader */
     $loader = \Drupal::service('twig.loader.filesystem');
@@ -108,8 +112,10 @@ class TwigIncludeTest extends KernelTestBase {
     // Allow files with no extension.
     $twig_config['allowed_file_extensions'] = ['twig', ''];
     $this->twigConfig = $twig_config;
-    $this->container->get('kernel')->shutdown();
-    $this->container->get('kernel')->boot();
+    // @todo This used to call shutdown() and boot(). rebuildContainer() is
+    // needed until we stop pushing the request twice and only popping it once.
+    // @see https://www.drupal.org/i/2613044
+    $this->container->get('kernel')->rebuildContainer();
     /** @var \Drupal\Core\Template\Loader\FilesystemLoader $loader */
     $loader = \Drupal::service('twig.loader.filesystem');
     $source = $loader->getSourceContext('@__main__\/' . $this->siteDirectory . '/test_file');

core/modules/system/tests/src/Kernel/Token/TokenReplaceKernelTest.php

@@ -7,6 +7,8 @@ use Drupal\Component\Utility\Html;
 use Drupal\Component\Utility\Xss;
 use Drupal\Core\Render\BubbleableMetadata;
 use Symfony\Component\HttpFoundation\Request;
+use Symfony\Component\HttpFoundation\Session\Session;
+use Symfony\Component\HttpFoundation\Session\Storage\MockArraySessionStorage;
 
 /**
  * Tests token replacement.
@@ -137,6 +139,7 @@ class TokenReplaceKernelTest extends TokenReplaceKernelTestBase {
       'SERVER_NAME' => 'http://localhost',
     ];
     $request = Request::create('/subdir/', 'GET', [], [], [], $server);
+    $request->setSession(new Session(new MockArraySessionStorage()));
     $request->server->add($server);
     $request_stack->push($request);
     $bubbleable_metadata = new BubbleableMetadata();

core/modules/views/src/Tests/AssertViewsCacheTagsTrait.php

@@ -6,6 +6,8 @@ use Drupal\Core\Cache\Cache;
 use Drupal\views\Plugin\views\display\DisplayPluginBase;
 use Drupal\views\ViewExecutable;
 use Symfony\Component\HttpFoundation\Request;
+use Symfony\Component\HttpFoundation\Session\Session;
+use Symfony\Component\HttpFoundation\Session\Storage\MockArraySessionStorage;
 
 trait AssertViewsCacheTagsTrait {
 
@@ -43,6 +45,7 @@ trait AssertViewsCacheTagsTrait {
     $request_stack = \Drupal::service('request_stack');
     $request = Request::createFromGlobals();
     $request->server->set('REQUEST_TIME', REQUEST_TIME);
+    $request->setSession(new Session(new MockArraySessionStorage()));
     $view->setRequest($request);
     $request_stack->push($request);
     $renderer->renderRoot($build);
@@ -123,6 +126,7 @@ trait AssertViewsCacheTagsTrait {
     $request_stack = \Drupal::service('request_stack');
     $request = new Request();
     $request->server->set('REQUEST_TIME', REQUEST_TIME);
+    $request->setSession(new Session(new MockArraySessionStorage()));
     $request_stack->push($request);
     $renderer->renderRoot($build);
 

core/modules/views/tests/src/Kernel/Handler/AreaDisplayLinkTest.php

@@ -15,6 +15,8 @@ use Prophecy\Argument;
 use Psr\Log\LoggerInterface;
 use Symfony\Component\HttpFoundation\Request;
 use Symfony\Component\HttpFoundation\RequestStack;
+use Symfony\Component\HttpFoundation\Session\Session;
+use Symfony\Component\HttpFoundation\Session\Storage\MockArraySessionStorage;
 
 /**
  * Tests the core views_handler_area_display_link handler.
@@ -148,8 +150,7 @@ class AreaDisplayLinkTest extends ViewsKernelTestBase {
 
     // Assert some special request parameters are filtered from the display
     // links.
-    $request_stack = new RequestStack();
-    $request_stack->push(Request::create('page_1', 'GET', [
+    $request = Request::create('page_1', 'GET', [
       'name' => 'John',
       'sort_by' => 'created',
       'sort_order' => 'ASC',
@@ -166,7 +167,10 @@ class AreaDisplayLinkTest extends ViewsKernelTestBase {
       AjaxResponseSubscriber::AJAX_REQUEST_PARAMETER => 1,
       FormBuilderInterface::AJAX_FORM_REQUEST => 1,
       MainContentViewSubscriber::WRAPPER_FORMAT => 1,
-    ]));
+    ]);
+    $request->setSession(new Session(new MockArraySessionStorage()));
+    $request_stack = new RequestStack();
+    $request_stack->push($request);
     $this->container->set('request_stack', $request_stack);
     $view->destroy();
     $view->setDisplay('page_1');

core/tests/Drupal/FunctionalTests/BrowserTestBaseTest.php

@@ -11,6 +11,7 @@ use Drupal\Tests\StreamCapturer;
 use Drupal\Tests\Traits\Core\CronRunTrait;
 use Drupal\user\Entity\Role;
 use PHPUnit\Framework\ExpectationFailedException;
+use Symfony\Component\HttpFoundation\Request;
 
 /**
  * Tests BrowserTestBase functionality.
@@ -521,6 +522,30 @@ class BrowserTestBaseTest extends BrowserTestBase {
     $this->assertSession()->statusCodeEquals(403);
   }
 
+  /**
+   * Tests that a usable session is on the request in test-runner.
+   */
+  public function testSessionOnRequest(): void {
+    /** @var \Symfony\Component\HttpFoundation\Session\Session $session */
+    $session = $this->container->get('request_stack')->getSession();
+
+    $session->set('some-val', 'do-not-cleanup');
+    $this->assertEquals('do-not-cleanup', $session->get('some-val'));
+
+    $session->set('some-other-val', 'do-cleanup');
+    $this->assertEquals('do-cleanup', $session->remove('some-other-val'));
+  }
+
+  /**
+   * Tests deprecation of modified request stack lacking a session.
+   *
+   * @group legacy
+   */
+  public function testDeprecatedSessionMissing(): void {
+    $this->expectDeprecation('Pushing requests without a session onto the request_stack is deprecated in drupal:10.3.0 and an error will be thrown from drupal:11.0.0. See https://www.drupal.org/node/3337193');
+    $this->container->get('request_stack')->push(Request::create('/'));
+  }
+
   /**
    * Tests that deprecation headers do not get duplicated.
    *

core/tests/Drupal/FunctionalTests/Installer/InstallerTestBase.php

@@ -15,6 +15,8 @@ use Symfony\Component\DependencyInjection\ContainerBuilder;
 use Symfony\Component\DependencyInjection\Reference;
 use Symfony\Component\HttpFoundation\Request;
 use Symfony\Component\HttpFoundation\RequestStack;
+use Symfony\Component\HttpFoundation\Session\Session;
+use Symfony\Component\HttpFoundation\Session\Storage\MockArraySessionStorage;
 
 /**
  * Base class for testing the interactive installer.
@@ -118,6 +120,7 @@ abstract class InstallerTestBase extends BrowserTestBase {
     // server information so that XDebug works.
     // @see install_begin_request()
     $request = Request::create($GLOBALS['base_url'] . '/core/install.php', 'GET', [], $_COOKIE, [], $_SERVER);
+    $request->setSession(new Session(new MockArraySessionStorage()));
     $this->container = new ContainerBuilder();
     $request_stack = new RequestStack();
     $request_stack->push($request);

core/tests/Drupal/KernelTests/Core/Entity/EntityQueryTest.php

@@ -13,6 +13,8 @@ use Drupal\taxonomy\Entity\Term;
 use Drupal\taxonomy\Entity\Vocabulary;
 use Drupal\Tests\field\Traits\EntityReferenceFieldCreationTrait;
 use Symfony\Component\HttpFoundation\Request;
+use Symfony\Component\HttpFoundation\Session\Session;
+use Symfony\Component\HttpFoundation\Session\Storage\MockArraySessionStorage;
 
 // cspell:ignore merhaba siema xsiemax
 
@@ -464,6 +466,7 @@ class EntityQueryTest extends EntityKernelTestBase {
     $request->query->replace([
       'page' => '0,2',
     ]);
+    $request->setSession(new Session(new MockArraySessionStorage()));
     \Drupal::getContainer()->get('request_stack')->push($request);
     $this->queryResults = $this->storage
       ->getQuery()
@@ -500,6 +503,7 @@ class EntityQueryTest extends EntityKernelTestBase {
       'sort' => 'asc',
       'order' => 'Type',
     ]);
+    $request->setSession(new Session(new MockArraySessionStorage()));
     \Drupal::getContainer()->get('request_stack')->push($request);
 
     $header = [

core/tests/Drupal/KernelTests/Core/File/FileUrlGeneratorTest.php

@@ -4,6 +4,8 @@ namespace Drupal\KernelTests\Core\File;
 
 use Drupal\Core\File\Exception\InvalidStreamWrapperException;
 use Symfony\Component\HttpFoundation\Request;
+use Symfony\Component\HttpFoundation\Session\Session;
+use Symfony\Component\HttpFoundation\Session\Storage\MockArraySessionStorage;
 
 /**
  * @coversDefaultClass \Drupal\Core\File\FileUrlGenerator
@@ -154,6 +156,7 @@ class FileUrlGeneratorTest extends FileTestBase {
 
     // Create a mock Request for transformRelative().
     $request = Request::create($GLOBALS['base_url']);
+    $request->setSession(new Session(new MockArraySessionStorage()));
     $this->container->get('request_stack')->push($request);
     \Drupal::setContainer($this->container);
 
@@ -183,6 +186,7 @@ class FileUrlGeneratorTest extends FileTestBase {
 
     // Create a mock Request for transformRelative().
     $request = Request::create($GLOBALS['base_url']);
+    $request->setSession(new Session(new MockArraySessionStorage()));
     $this->container->get('request_stack')->push($request);
     \Drupal::setContainer($this->container);
 
@@ -200,6 +204,7 @@ class FileUrlGeneratorTest extends FileTestBase {
 
     // Create a mock Request for transformRelative().
     $request = Request::create($GLOBALS['base_url']);
+    $request->setSession(new Session(new MockArraySessionStorage()));
     $this->container->get('request_stack')->push($request);
     \Drupal::setContainer($this->container);
 

core/tests/Drupal/KernelTests/Core/File/UrlTransformRelativeTest.php

@@ -4,6 +4,8 @@ namespace Drupal\KernelTests\Core\File;
 
 use Drupal\KernelTests\KernelTestBase;
 use Symfony\Component\HttpFoundation\Request;
+use Symfony\Component\HttpFoundation\Session\Session;
+use Symfony\Component\HttpFoundation\Session\Storage\MockArraySessionStorage;
 
 /**
  * Tests URL transform to relative.
@@ -35,6 +37,7 @@ class UrlTransformRelativeTest extends KernelTestBase {
     $_SERVER['HTTPS'] = $https;
 
     $request = Request::createFromGlobals();
+    $request->setSession(new Session(new MockArraySessionStorage()));
     \Drupal::requestStack()->push($request);
 
     $this->assertSame($expected, \Drupal::service('file_url_generator')->transformRelative($url, $root_relative));

core/tests/Drupal/KernelTests/Core/Form/ExternalFormUrlTest.php

@@ -7,6 +7,8 @@ use Drupal\Core\Form\FormStateInterface;
 use Drupal\KernelTests\KernelTestBase;
 use Drupal\user\Entity\User;
 use Symfony\Component\HttpFoundation\Request;
+use Symfony\Component\HttpFoundation\Session\Session;
+use Symfony\Component\HttpFoundation\Session\Storage\MockArraySessionStorage;
 
 /**
  * Ensures that form actions can't be tricked into sending to external URLs.
@@ -76,6 +78,7 @@ class ExternalFormUrlTest extends KernelTestBase implements FormInterface {
     $request_stack->pop();
     $request_stack->pop();
     $request = Request::create($original_request->getSchemeAndHttpHost() . '//example.org');
+    $request->setSession(new Session(new MockArraySessionStorage()));
     $request_stack->push($request);
 
     $form = \Drupal::formBuilder()->getForm($this);
@@ -91,6 +94,7 @@ class ExternalFormUrlTest extends KernelTestBase implements FormInterface {
     $request_stack = \Drupal::service('request_stack');
     $original_request = $request_stack->pop();
     $request = Request::create($original_request->getSchemeAndHttpHost() . '/example.org');
+    $request->setSession(new Session(new MockArraySessionStorage()));
     $request_stack->push($request);
 
     $form = \Drupal::formBuilder()->getForm($this);

core/tests/Drupal/KernelTests/Core/Form/FormActionXssTest.php

@@ -7,6 +7,8 @@ use Drupal\Core\Form\FormStateInterface;
 use Drupal\KernelTests\KernelTestBase;
 use Drupal\user\Entity\User;
 use Symfony\Component\HttpFoundation\Request;
+use Symfony\Component\HttpFoundation\Session\Session;
+use Symfony\Component\HttpFoundation\Session\Storage\MockArraySessionStorage;
 
 // cspell:ignore attribute\'close
 
@@ -77,6 +79,7 @@ class FormActionXssTest extends KernelTestBase implements FormInterface {
     $request_stack->pop();
     $request_stack->pop();
     $request = Request::create($original_request->getSchemeAndHttpHost() . '/test/"injected=\'attribute\'close="');
+    $request->setSession(new Session(new MockArraySessionStorage()));
     $request_stack->push($request);
 
     $form = \Drupal::formBuilder()->getForm($this);

core/tests/Drupal/KernelTests/Core/Pager/PagerManagerTest.php

@@ -4,6 +4,8 @@ namespace Drupal\KernelTests\Core\Pager;
 
 use Drupal\KernelTests\KernelTestBase;
 use Symfony\Component\HttpFoundation\Request;
+use Symfony\Component\HttpFoundation\Session\Session;
+use Symfony\Component\HttpFoundation\Session\Storage\MockArraySessionStorage;
 
 /**
  * @group Pager
@@ -22,6 +24,7 @@ class PagerManagerTest extends KernelTestBase {
       'other' => 'arbitrary',
     ];
     $request = Request::create('http://example.com', 'GET', $test_parameters);
+    $request->setSession(new Session(new MockArraySessionStorage()));
 
     /** @var \Symfony\Component\HttpFoundation\RequestStack $request_stack */
     $request_stack = $this->container->get('request_stack');
@@ -43,6 +46,7 @@ class PagerManagerTest extends KernelTestBase {
    */
   public function testFindPage() {
     $request = Request::create('http://example.com', 'GET', ['page' => '0,10']);
+    $request->setSession(new Session(new MockArraySessionStorage()));
 
     /** @var \Symfony\Component\HttpFoundation\RequestStack $request_stack */
     $request_stack = $this->container->get('request_stack');

core/tests/Drupal/KernelTests/Core/Pager/RequestPagerTest.php

@@ -4,6 +4,8 @@ namespace Drupal\KernelTests\Core\Pager;
 
 use Drupal\KernelTests\KernelTestBase;
 use Symfony\Component\HttpFoundation\Request;
+use Symfony\Component\HttpFoundation\Session\Session;
+use Symfony\Component\HttpFoundation\Session\Storage\MockArraySessionStorage;
 
 /**
  * @group Pager
@@ -17,6 +19,7 @@ class RequestPagerTest extends KernelTestBase {
    */
   public function testFindPage() {
     $request = Request::create('http://example.com', 'GET', ['page' => '0,10']);
+    $request->setSession(new Session(new MockArraySessionStorage()));
 
     /** @var \Symfony\Component\HttpFoundation\RequestStack $request_stack */
     $request_stack = $this->container->get('request_stack');
@@ -35,6 +38,7 @@ class RequestPagerTest extends KernelTestBase {
       'other' => 'arbitrary',
     ];
     $request = Request::create('http://example.com', 'GET', array_merge(['page' => '0,10'], $test_parameters));
+    $request->setSession(new Session(new MockArraySessionStorage()));
 
     /** @var \Symfony\Component\HttpFoundation\RequestStack $request_stack */
     $request_stack = $this->container->get('request_stack');

core/tests/Drupal/KernelTests/Core/Path/PathValidatorTest.php

@@ -55,10 +55,12 @@ class PathValidatorTest extends KernelTestBase {
       FALSE,
     ];
     foreach ($methods as $method) {
+      /** @var \Symfony\Component\HttpFoundation\Request|null $request */
+      $request = NULL;
       if ($method === FALSE) {
         $request_stack = $this->container->get('request_stack');
         while ($request_stack->getCurrentRequest()) {
-          $request_stack->pop();
+          $request = $request_stack->pop();
         }
         $this->container->set('router.request_context', new RequestContext());
       }
@@ -69,6 +71,12 @@ class PathValidatorTest extends KernelTestBase {
       $this->assertEquals($method, $requestContext->getMethod());
       $this->assertInstanceOf(Url::class, $url);
       $this->assertSame(['entity_test' => $entity->id()], $url->getRouteParameters());
+
+      if ($method === FALSE) {
+        // Restore main request.
+        $request_stack = $this->container->get('request_stack');
+        $request_stack->push($request);
+      }
     }
   }
 

core/tests/Drupal/KernelTests/Core/Plugin/Condition/RequestPathTest.php

@@ -7,6 +7,8 @@ use Drupal\KernelTests\KernelTestBase;
 use Drupal\system\Tests\Routing\MockAliasManager;
 use Symfony\Component\HttpFoundation\Request;
 use Symfony\Component\HttpFoundation\RequestStack;
+use Symfony\Component\HttpFoundation\Session\Session;
+use Symfony\Component\HttpFoundation\Session\Storage\MockArraySessionStorage;
 
 /**
  * Tests system.module's request path condition.
@@ -83,6 +85,7 @@ class RequestPathTest extends KernelTestBase {
     $pages = "/my/pass/page\r\n/my/pass/page2\r\n/foo";
 
     $request = Request::create('/my/pass/page2');
+    $request->setSession(new Session(new MockArraySessionStorage()));
     $this->requestStack->push($request);
 
     /** @var \Drupal\system\Plugin\Condition\RequestPath $condition */

core/tests/Drupal/KernelTests/Core/Plugin/Condition/ResponseStatusTest.php

@@ -9,6 +9,8 @@ use Drupal\KernelTests\KernelTestBase;
 use Symfony\Component\HttpFoundation\Request;
 use Symfony\Component\HttpFoundation\RequestStack;
 use Symfony\Component\HttpFoundation\Response;
+use Symfony\Component\HttpFoundation\Session\Session;
+use Symfony\Component\HttpFoundation\Session\Storage\MockArraySessionStorage;
 use Symfony\Component\HttpKernel\Exception\HttpException;
 
 /**
@@ -61,6 +63,7 @@ class ResponseStatusTest extends KernelTestBase {
       $request = new Request();
       $request->attributes->set('exception', new HttpException($response_code));
     }
+    $request->setSession(new Session(new MockArraySessionStorage()));
     $this->requestStack->push($request);
 
     /** @var \Drupal\system\Plugin\Condition\ResponseStatus $condition */

core/tests/Drupal/KernelTests/Core/Render/Element/TableSortExtenderTest.php

@@ -5,6 +5,8 @@ namespace Drupal\KernelTests\Core\Render\Element;
 use Drupal\Core\Utility\TableSort;
 use Drupal\KernelTests\KernelTestBase;
 use Symfony\Component\HttpFoundation\Request;
+use Symfony\Component\HttpFoundation\Session\Session;
+use Symfony\Component\HttpFoundation\Session\Storage\MockArraySessionStorage;
 
 /**
  * Tests table sorting.
@@ -31,6 +33,7 @@ class TableSortExtenderTest extends KernelTestBase {
     ];
     $request = Request::createFromGlobals();
     $request->query->replace([]);
+    $request->setSession(new Session(new MockArraySessionStorage()));
     \Drupal::getContainer()->get('request_stack')->push($request);
     $ts = TableSort::getContextFromRequest($headers, $request);
     $this->assertEquals($expected_ts, $ts, 'Simple table headers sorted correctly.');
@@ -43,6 +46,7 @@ class TableSortExtenderTest extends KernelTestBase {
       // headers are overridable.
       'order' => 'bar',
     ]);
+    $request->setSession(new Session(new MockArraySessionStorage()));
     \Drupal::getContainer()->get('request_stack')->push($request);
     $ts = TableSort::getContextFromRequest($headers, $request);
     $this->assertEquals($expected_ts, $ts, 'Simple table headers plus non-overriding $_GET parameters sorted correctly.');
@@ -56,6 +60,7 @@ class TableSortExtenderTest extends KernelTestBase {
       // it in the links that it creates.
       'alpha' => 'beta',
     ]);
+    $request->setSession(new Session(new MockArraySessionStorage()));
     \Drupal::getContainer()->get('request_stack')->push($request);
     $expected_ts['sort'] = 'desc';
     $expected_ts['query'] = ['alpha' => 'beta'];
@@ -83,6 +88,7 @@ class TableSortExtenderTest extends KernelTestBase {
     $request->query->replace([
       'order' => '2',
     ]);
+    $request->setSession(new Session(new MockArraySessionStorage()));
     \Drupal::getContainer()->get('request_stack')->push($request);
     $ts = TableSort::getContextFromRequest($headers, $request);
     $expected_ts = [
@@ -101,6 +107,7 @@ class TableSortExtenderTest extends KernelTestBase {
       // exist.
       'order' => 'bar',
     ]);
+    $request->setSession(new Session(new MockArraySessionStorage()));
     \Drupal::getContainer()->get('request_stack')->push($request);
     $ts = TableSort::getContextFromRequest($headers, $request);
     $expected_ts = [
@@ -121,6 +128,7 @@ class TableSortExtenderTest extends KernelTestBase {
       // it in the links that it creates.
       'alpha' => 'beta',
     ]);
+    $request->setSession(new Session(new MockArraySessionStorage()));
     \Drupal::getContainer()->get('request_stack')->push($request);
     $expected_ts = [
       'name' => '1',
@@ -165,6 +173,7 @@ class TableSortExtenderTest extends KernelTestBase {
     $request->query->replace([
       'order' => '1',
     ]);
+    $request->setSession(new Session(new MockArraySessionStorage()));
     \Drupal::getContainer()->get('request_stack')->push($request);
     $ts = TableSort::getContextFromRequest($headers, $request);
     $expected_ts = [
@@ -181,6 +190,7 @@ class TableSortExtenderTest extends KernelTestBase {
     $request->query->replace([
       'order' => '2',
     ]);
+    $request->setSession(new Session(new MockArraySessionStorage()));
     \Drupal::getContainer()->get('request_stack')->push($request);
     $ts = TableSort::getContextFromRequest($headers, $request);
     $expected_ts = [
@@ -197,6 +207,7 @@ class TableSortExtenderTest extends KernelTestBase {
     $request->query->replace([
       'order' => '3',
     ]);
+    $request->setSession(new Session(new MockArraySessionStorage()));
     \Drupal::getContainer()->get('request_stack')->push($request);
     $ts = TableSort::getContextFromRequest($headers, $request);
     $expected_ts = [
@@ -213,6 +224,7 @@ class TableSortExtenderTest extends KernelTestBase {
     $request->query->replace([
       'order' => '4',
     ]);
+    $request->setSession(new Session(new MockArraySessionStorage()));
     \Drupal::getContainer()->get('request_stack')->push($request);
     $ts = TableSort::getContextFromRequest($headers, $request);
     $expected_ts = [
@@ -229,6 +241,7 @@ class TableSortExtenderTest extends KernelTestBase {
     $request->query->replace([
       'order' => '5',
     ]);
+    $request->setSession(new Session(new MockArraySessionStorage()));
     \Drupal::getContainer()->get('request_stack')->push($request);
     $ts = TableSort::getContextFromRequest($headers, $request);
     $expected_ts = [

core/tests/Drupal/KernelTests/Core/RouteProcessor/RouteNoneTest.php

@@ -8,6 +8,8 @@ use Drupal\Core\Render\BubbleableMetadata;
 use Drupal\KernelTests\KernelTestBase;
 use Drupal\Core\Routing\RouteObjectInterface;
 use Symfony\Component\HttpFoundation\Request;
+use Symfony\Component\HttpFoundation\Session\Session;
+use Symfony\Component\HttpFoundation\Session\Storage\MockArraySessionStorage;
 use Symfony\Component\Routing\Route;
 
 /**
@@ -59,6 +61,7 @@ class RouteNoneTest extends KernelTestBase {
     $request = Request::create('/subdir', 'GET', [], [], [], $server);
     $request->attributes->set(RouteObjectInterface::ROUTE_NAME, '<front>');
     $request->attributes->set(RouteObjectInterface::ROUTE_OBJECT, new Route('/'));
+    $request->setSession(new Session(new MockArraySessionStorage()));
 
     $request_stack->push($request);
     $request_context->fromRequest($request);
@@ -76,6 +79,7 @@ class RouteNoneTest extends KernelTestBase {
     $request = Request::create('/subdir/node/add', 'GET', [], [], [], $server);
     $request->attributes->set(RouteObjectInterface::ROUTE_NAME, 'node.add');
     $request->attributes->set(RouteObjectInterface::ROUTE_OBJECT, new Route('/node/add'));
+    $request->setSession(new Session(new MockArraySessionStorage()));
 
     $request_stack->push($request);
     $request_context->fromRequest($request);
@@ -93,6 +97,7 @@ class RouteNoneTest extends KernelTestBase {
     $request = Request::create('/', 'GET', [], [], [], $server);
     $request->attributes->set(RouteObjectInterface::ROUTE_NAME, '<front>');
     $request->attributes->set(RouteObjectInterface::ROUTE_OBJECT, new Route('/'));
+    $request->setSession(new Session(new MockArraySessionStorage()));
 
     $request_stack->push($request);
     $request_context->fromRequest($request);
@@ -110,6 +115,7 @@ class RouteNoneTest extends KernelTestBase {
     $request = Request::create('/node/add', 'GET', [], [], [], $server);
     $request->attributes->set(RouteObjectInterface::ROUTE_NAME, 'node.add');
     $request->attributes->set(RouteObjectInterface::ROUTE_OBJECT, new Route('/node/add'));
+    $request->setSession(new Session(new MockArraySessionStorage()));
 
     $request_stack->push($request);
     $request_context->fromRequest($request);

core/tests/Drupal/KernelTests/Core/RouteProcessor/RouteProcessorCurrentIntegrationTest.php

@@ -8,6 +8,8 @@ use Drupal\Core\Render\BubbleableMetadata;
 use Drupal\KernelTests\KernelTestBase;
 use Drupal\Core\Routing\RouteObjectInterface;
 use Symfony\Component\HttpFoundation\Request;
+use Symfony\Component\HttpFoundation\Session\Session;
+use Symfony\Component\HttpFoundation\Session\Storage\MockArraySessionStorage;
 use Symfony\Component\Routing\Route;
 
 /**
@@ -60,6 +62,7 @@ class RouteProcessorCurrentIntegrationTest extends KernelTestBase {
     $request = Request::create('/subdir/', 'GET', [], [], [], $server);
     $request->attributes->set(RouteObjectInterface::ROUTE_NAME, '<front>');
     $request->attributes->set(RouteObjectInterface::ROUTE_OBJECT, new Route('/'));
+    $request->setSession(new Session(new MockArraySessionStorage()));
 
     $request_stack->push($request);
     $request_context->fromRequest($request);
@@ -75,6 +78,7 @@ class RouteProcessorCurrentIntegrationTest extends KernelTestBase {
     $request = Request::create('/subdir/node/add', 'GET', [], [], [], $server);
     $request->attributes->set(RouteObjectInterface::ROUTE_NAME, 'node.add');
     $request->attributes->set(RouteObjectInterface::ROUTE_OBJECT, new Route('/node/add'));
+    $request->setSession(new Session(new MockArraySessionStorage()));
 
     $request_stack->push($request);
     $request_context->fromRequest($request);
@@ -90,6 +94,7 @@ class RouteProcessorCurrentIntegrationTest extends KernelTestBase {
     $request = Request::create('/', 'GET', [], [], [], $server);
     $request->attributes->set(RouteObjectInterface::ROUTE_NAME, '<front>');
     $request->attributes->set(RouteObjectInterface::ROUTE_OBJECT, new Route('/'));
+    $request->setSession(new Session(new MockArraySessionStorage()));
 
     $request_stack->push($request);
     $request_context->fromRequest($request);
@@ -105,6 +110,7 @@ class RouteProcessorCurrentIntegrationTest extends KernelTestBase {
     $request = Request::create('/node/add', 'GET', [], [], [], $server);
     $request->attributes->set(RouteObjectInterface::ROUTE_NAME, 'node.add');
     $request->attributes->set(RouteObjectInterface::ROUTE_OBJECT, new Route('/node/add'));
+    $request->setSession(new Session(new MockArraySessionStorage()));
 
     $request_stack->push($request);
     $request_context->fromRequest($request);
@@ -119,6 +125,7 @@ class RouteProcessorCurrentIntegrationTest extends KernelTestBase {
       'SERVER_NAME' => 'http://www.example.com',
     ];
     $request = Request::create('/invalid-path', 'GET', [], [], [], $server);
+    $request->setSession(new Session(new MockArraySessionStorage()));
 
     $request_stack->push($request);
     $request_context->fromRequest($request);

core/tests/Drupal/KernelTests/Core/StringTranslation/TranslationStringTest.php

@@ -58,8 +58,10 @@ class TranslationStringTest extends KernelTestBase {
     // Reboot the container so that different services are injected and the new
     // settings are picked.
     $kernel = $this->container->get('kernel');
-    $kernel->shutdown();
-    $kernel->boot();
+    // @todo This used to call shutdown() and boot(). rebuildContainer() is
+    // needed until we stop pushing the request twice and only popping it once.
+    // @see https://www.drupal.org/i/2613044
+    $kernel->rebuildContainer();
     $settings = Settings::getAll();
     $settings['locale_custom_strings_de'] = ['' => ['Example @number' => 'Example @number translated']];
     // Recreate the settings static.

core/tests/Drupal/KernelTests/Core/Theme/ImageTest.php

@@ -4,6 +4,8 @@ namespace Drupal\KernelTests\Core\Theme;
 
 use Drupal\KernelTests\KernelTestBase;
 use Symfony\Component\HttpFoundation\Request;
+use Symfony\Component\HttpFoundation\Session\Session;
+use Symfony\Component\HttpFoundation\Session\Storage\MockArraySessionStorage;
 
 /**
  * Tests built-in image theme functions.
@@ -43,6 +45,7 @@ class ImageTest extends KernelTestBase {
     // the Request containing the correct hostname. KernelTestBase doesn't set
     // it, so push another request onto the stack to ensure it's correct.
     $request = Request::create('/', 'GET', [], [], [], $_SERVER);
+    $request->setSession(new Session(new MockArraySessionStorage()));
     $this->container = \Drupal::service('kernel')->getContainer();
     $this->container->get('request_stack')->push($request);
 

core/tests/Drupal/KernelTests/KernelTestBase.php

@@ -37,6 +37,7 @@ use Drupal\Core\Routing\RouteObjectInterface;
 use Symfony\Component\Routing\Route;
 use Symfony\Component\VarDumper\VarDumper;
 use Symfony\Bridge\PhpUnit\ExpectDeprecationTrait;
+use Symfony\Component\HttpFoundation\Exception\SessionNotFoundException;
 
 /**
  * Base class for functional integration tests.
@@ -667,6 +668,19 @@ abstract class KernelTestBase extends TestCase implements ServiceProviderInterfa
    * {@inheritdoc}
    */
   protected function tearDown(): void {
+    if ($this->container) {
+      // Clean up mock session started in DrupalKernel::preHandle().
+      try {
+        /** @var \Symfony\Component\HttpFoundation\Session\Session $session */
+        $session = $this->container->get('request_stack')->getSession();
+        $session->clear();
+        $session->save();
+      }
+      catch (SessionNotFoundException) {
+        @trigger_error('Pushing requests without a session onto the request_stack is deprecated in drupal:10.3.0 and an error will be thrown from drupal:11.0.0. See https://www.drupal.org/node/3337193', E_USER_DEPRECATED);
+      }
+    }
+
     // Destroy the testing kernel.
     if (isset($this->kernel)) {
       $this->kernel->shutdown();

core/tests/Drupal/KernelTests/KernelTestBaseTest.php

@@ -11,6 +11,7 @@ use Drupal\user\Entity\Role;
 use org\bovigo\vfs\vfsStream;
 use org\bovigo\vfs\visitor\vfsStreamStructureVisitor;
 use PHPUnit\Framework\SkippedTestError;
+use Symfony\Component\HttpFoundation\Request;
 
 /**
  * @coversDefaultClass \Drupal\KernelTests\KernelTestBase
@@ -235,6 +236,34 @@ class KernelTestBaseTest extends KernelTestBase {
     $this->assertEquals('public', \Drupal::config('system.file')->get('default_scheme'));
   }
 
+  /**
+   * Tests that a usable session is on the request.
+   *
+   * @covers ::bootKernel
+   */
+  public function testSessionOnRequest(): void {
+    /** @var \Symfony\Component\HttpFoundation\Session\Session $session */
+    $session = $this->container->get('request_stack')->getSession();
+
+    $session->set('some-val', 'do-not-cleanup');
+    $this->assertEquals('do-not-cleanup', $session->get('some-val'));
+
+    $session->set('some-other-val', 'do-cleanup');
+    $this->assertEquals('do-cleanup', $session->remove('some-other-val'));
+  }
+
+  /**
+   * Tests deprecation of modified request stack lacking a session.
+   *
+   * @covers ::tearDown
+   *
+   * @group legacy
+   */
+  public function testDeprecatedSessionMissing(): void {
+    $this->expectDeprecation('Pushing requests without a session onto the request_stack is deprecated in drupal:10.3.0 and an error will be thrown from drupal:11.0.0. See https://www.drupal.org/node/3337193');
+    $this->container->get('request_stack')->push(Request::create('/'));
+  }
+
   /**
    * Tests the assumption that local time is in 'Australia/Sydney'.
    */

core/tests/Drupal/Tests/BrowserTestBase.php

@@ -24,6 +24,7 @@ use Drupal\TestTools\TestVarDumper;
 use GuzzleHttp\Cookie\CookieJar;
 use PHPUnit\Framework\TestCase;
 use Symfony\Bridge\PhpUnit\ExpectDeprecationTrait;
+use Symfony\Component\HttpFoundation\Exception\SessionNotFoundException;
 use Symfony\Component\VarDumper\VarDumper;
 
 /**
@@ -446,6 +447,19 @@ abstract class BrowserTestBase extends TestCase {
   protected function tearDown(): void {
     parent::tearDown();
 
+    if ($this->container) {
+      // Cleanup mock session started in DrupalKernel::preHandle().
+      try {
+        /** @var \Symfony\Component\HttpFoundation\Session\Session $session */
+        $session = $this->container->get('request_stack')->getSession();
+        $session->clear();
+        $session->save();
+      }
+      catch (SessionNotFoundException) {
+        @trigger_error('Pushing requests without a session onto the request_stack is deprecated in drupal:10.3.0 and an error will be thrown from drupal:11.0.0. See https://www.drupal.org/node/3337193', E_USER_DEPRECATED);
+      }
+    }
+
     // Destroy the testing kernel.
     if (isset($this->kernel)) {
       $this->cleanupEnvironment();