comparison core/lib/Drupal/Core/Test/FunctionalTestSetupTrait.php @ 0:4c8ae668cc8c

Initial import (non-working)

+<?php
+
+namespace Drupal\Core\Test;
+
+use Drupal\Component\FileCache\FileCacheFactory;
+use Drupal\Component\Utility\SafeMarkup;
+use Drupal\Core\Cache\Cache;
+use Drupal\Core\Config\Development\ConfigSchemaChecker;
+use Drupal\Core\Database\Database;
+use Drupal\Core\DrupalKernel;
+use Drupal\Core\Extension\MissingDependencyException;
+use Drupal\Core\Serialization\Yaml;
+use Drupal\Core\Session\UserSession;
+use Drupal\Core\Site\Settings;
+use Drupal\Core\StreamWrapper\StreamWrapperInterface;
+use Symfony\Component\DependencyInjection\ContainerInterface;
+use Symfony\Component\HttpFoundation\Request;
+use Symfony\Component\Yaml\Yaml as SymfonyYaml;
+
+/**
+ * Defines a trait for shared functional test setup functionality.
+ */
+trait FunctionalTestSetupTrait {
+
+  /**
+   * The "#1" admin user.
+   *
+   * @var \Drupal\Core\Session\AccountInterface
+   */
+  protected $rootUser;
+
+  /**
+   * The class loader to use for installation and initialization of setup.
+   *
+   * @var \Symfony\Component\Classloader\Classloader
+   */
+  protected $classLoader;
+
+  /**
+   * The config directories used in this test.
+   */
+  protected $configDirectories = [];
+
+  /**
+   * Prepares site settings and services before installation.
+   */
+  protected function prepareSettings() {
+    // Prepare installer settings that are not install_drupal() parameters.
+    // Copy and prepare an actual settings.php, so as to resemble a regular
+    // installation.
+    // Not using File API; a potential error must trigger a PHP warning.
+    $directory = DRUPAL_ROOT . '/' . $this->siteDirectory;
+    copy(DRUPAL_ROOT . '/sites/default/default.settings.php', $directory . '/settings.php');
+
+    // The public file system path is created during installation. Additionally,
+    // during tests:
+    // - The temporary directory is set and created by install_base_system().
+    // - The private file directory is created post install by
+    //   FunctionalTestSetupTrait::initConfig().
+    // @see system_requirements()
+    // @see TestBase::prepareEnvironment()
+    // @see install_base_system()
+    // @see \Drupal\Core\Test\FunctionalTestSetupTrait::initConfig()
+    $settings['settings']['file_public_path'] = (object) [
+      'value' => $this->publicFilesDirectory,
+      'required' => TRUE,
+    ];
+    $settings['settings']['file_private_path'] = (object) [
+      'value' => $this->privateFilesDirectory,
+      'required' => TRUE,
+    ];
+    // Save the original site directory path, so that extensions in the
+    // site-specific directory can still be discovered in the test site
+    // environment.
+    // @see \Drupal\Core\Extension\ExtensionDiscovery::scan()
+    $settings['settings']['test_parent_site'] = (object) [
+      'value' => $this->originalSite,
+      'required' => TRUE,
+    ];
+    // Add the parent profile's search path to the child site's search paths.
+    // @see \Drupal\Core\Extension\ExtensionDiscovery::getProfileDirectories()
+    $settings['conf']['simpletest.settings']['parent_profile'] = (object) [
+      'value' => $this->originalProfile,
+      'required' => TRUE,
+    ];
+    $this->writeSettings($settings);
+    // Allow for test-specific overrides.
+    $settings_testing_file = DRUPAL_ROOT . '/' . $this->originalSite . '/settings.testing.php';
+    if (file_exists($settings_testing_file)) {
+      // Copy the testing-specific settings.php overrides in place.
+      copy($settings_testing_file, $directory . '/settings.testing.php');
+      // Add the name of the testing class to settings.php and include the
+      // testing specific overrides.
+      file_put_contents($directory . '/settings.php', "\n\$test_class = '" . get_class($this) . "';\n" . 'include DRUPAL_ROOT . \'/\' . $site_path . \'/settings.testing.php\';' . "\n", FILE_APPEND);
+    }
+    $settings_services_file = DRUPAL_ROOT . '/' . $this->originalSite . '/testing.services.yml';
+    if (!file_exists($settings_services_file)) {
+      // Otherwise, use the default services as a starting point for overrides.
+      $settings_services_file = DRUPAL_ROOT . '/sites/default/default.services.yml';
+    }
+    // Copy the testing-specific service overrides in place.
+    copy($settings_services_file, $directory . '/services.yml');
+    if ($this->strictConfigSchema) {
+      // Add a listener to validate configuration schema on save.
+      $yaml = new SymfonyYaml();
+      $content = file_get_contents($directory . '/services.yml');
+      $services = $yaml->parse($content);
+      $services['services']['simpletest.config_schema_checker'] = [
+        'class' => ConfigSchemaChecker::class,
+        'arguments' => ['@config.typed', $this->getConfigSchemaExclusions()],
+        'tags' => [['name' => 'event_subscriber']],
+      ];
+      file_put_contents($directory . '/services.yml', $yaml->dump($services));
+    }
+    // Since Drupal is bootstrapped already, install_begin_request() will not
+    // bootstrap again. Hence, we have to reload the newly written custom
+    // settings.php manually.
+    Settings::initialize(DRUPAL_ROOT, $this->siteDirectory, $this->classLoader);
+  }
+
+  /**
+   * Rewrites the settings.php file of the test site.
+   *
+   * @param array $settings
+   *   An array of settings to write out, in the format expected by
+   *   drupal_rewrite_settings().
+   *
+   * @see drupal_rewrite_settings()
+   */
+  protected function writeSettings(array $settings) {
+    include_once DRUPAL_ROOT . '/core/includes/install.inc';
+    $filename = $this->siteDirectory . '/settings.php';
+    // system_requirements() removes write permissions from settings.php
+    // whenever it is invoked.
+    // Not using File API; a potential error must trigger a PHP warning.
+    chmod($filename, 0666);
+    drupal_rewrite_settings($settings, $filename);
+  }
+
+  /**
+   * Changes parameters in the services.yml file.
+   *
+   * @param string $name
+   *   The name of the parameter.
+   * @param string $value
+   *   The value of the parameter.
+   */
+  protected function setContainerParameter($name, $value) {
+    $filename = $this->siteDirectory . '/services.yml';
+    chmod($filename, 0666);
+
+    $services = Yaml::decode(file_get_contents($filename));
+    $services['parameters'][$name] = $value;
+    file_put_contents($filename, Yaml::encode($services));
+
+    // Ensure that the cache is deleted for the yaml file loader.
+    $file_cache = FileCacheFactory::get('container_yaml_loader');
+    $file_cache->delete($filename);
+  }
+
+  /**
+   * Rebuilds \Drupal::getContainer().
+   *
+   * Use this to update the test process's kernel with a new service container.
+   * For example, when the list of enabled modules is changed via the internal
+   * browser the test process's kernel has a service container with an out of
+   * date module list.
+   *
+   * @see TestBase::prepareEnvironment()
+   * @see TestBase::restoreEnvironment()
+   *
+   * @todo Fix https://www.drupal.org/node/2021959 so that module enable/disable
+   *   changes are immediately reflected in \Drupal::getContainer(). Until then,
+   *   tests can invoke this workaround when requiring services from newly
+   *   enabled modules to be immediately available in the same request.
+   */
+  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();
+  }
+
+  /**
+   * Resets all data structures after having enabled new modules.
+   *
+   * This method is called by FunctionalTestSetupTrait::rebuildAll() after
+   * enabling the requested modules. It must be called again when additional
+   * modules are enabled later.
+   *
+   * @see \Drupal\Core\Test\FunctionalTestSetupTrait::rebuildAll()
+   * @see \Drupal\Tests\BrowserTestBase::installDrupal()
+   * @see \Drupal\simpletest\WebTestBase::setUp()
+   */
+  protected function resetAll() {
+    // Clear all database and static caches and rebuild data structures.
+    drupal_flush_all_caches();
+    $this->container = \Drupal::getContainer();
+
+    // Reset static variables and reload permissions.
+    $this->refreshVariables();
+  }
+
+  /**
+   * Refreshes in-memory configuration and state information.
+   *
+   * Useful after a page request is made that changes configuration or state in
+   * a different thread.
+   *
+   * In other words calling a settings page with $this->drupalPostForm() with a
+   * changed value would update configuration to reflect that change, but in the
+   * thread that made the call (thread running the test) the changed values
+   * would not be picked up.
+   *
+   * This method clears the cache and loads a fresh copy.
+   */
+  protected function refreshVariables() {
+    // Clear the tag cache.
+    \Drupal::service('cache_tags.invalidator')->resetChecksums();
+    foreach (Cache::getBins() as $backend) {
+      if (is_callable([$backend, 'reset'])) {
+        $backend->reset();
+      }
+    }
+
+    $this->container->get('config.factory')->reset();
+    $this->container->get('state')->resetCache();
+  }
+
+  /**
+   * Creates a mock request and sets it on the generator.
+   *
+   * This is used to manipulate how the generator generates paths during tests.
+   * It also ensures that calls to $this->drupalGet() will work when running
+   * from run-tests.sh because the url generator no longer looks at the global
+   * variables that are set there but relies on getting this information from a
+   * request object.
+   *
+   * @param bool $clean_urls
+   *   Whether to mock the request using clean urls.
+   * @param array $override_server_vars
+   *   An array of server variables to override.
+   *
+   * @return \Symfony\Component\HttpFoundation\Request
+   *   The mocked request object.
+   */
+  protected function prepareRequestForGenerator($clean_urls = TRUE, $override_server_vars = []) {
+    $request = Request::createFromGlobals();
+    $server = $request->server->all();
+    if (basename($server['SCRIPT_FILENAME']) != basename($server['SCRIPT_NAME'])) {
+      // We need this for when the test is executed by run-tests.sh.
+      // @todo Remove this once run-tests.sh has been converted to use a Request
+      //   object.
+      $cwd = getcwd();
+      $server['SCRIPT_FILENAME'] = $cwd . '/' . basename($server['SCRIPT_NAME']);
+      $base_path = rtrim($server['REQUEST_URI'], '/');
+    }
+    else {
+      $base_path = $request->getBasePath();
+    }
+    if ($clean_urls) {
+      $request_path = $base_path ? $base_path . '/user' : 'user';
+    }
+    else {
+      $request_path = $base_path ? $base_path . '/index.php/user' : '/index.php/user';
+    }
+    $server = array_merge($server, $override_server_vars);
+
+    $request = Request::create($request_path, 'GET', [], [], [], $server);
+    // 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);
+    $this->container->get('request_stack')->push($request);
+
+    // The request context is normally set by the router_listener from within
+    // its KernelEvents::REQUEST listener. In the simpletest parent site this
+    // event is not fired, therefore it is necessary to updated the request
+    // context manually here.
+    $this->container->get('router.request_context')->fromRequest($request);
+
+    return $request;
+  }
+
+  /**
+   * Execute the non-interactive installer.
+   *
+   * @see install_drupal()
+   */
+  protected function doInstall() {
+    require_once DRUPAL_ROOT . '/core/includes/install.core.inc';
+    install_drupal($this->classLoader, $this->installParameters());
+  }
+
+  /**
+   * Initialize settings created during install.
+   */
+  protected function initSettings() {
+    Settings::initialize(DRUPAL_ROOT, $this->siteDirectory, $this->classLoader);
+    foreach ($GLOBALS['config_directories'] as $type => $path) {
+      $this->configDirectories[$type] = $path;
+    }
+
+    // After writing settings.php, the installer removes write permissions
+    // from the site directory. To allow drupal_generate_test_ua() to write
+    // a file containing the private key for drupal_valid_test_ua(), the site
+    // directory has to be writable.
+    // TestBase::restoreEnvironment() will delete the entire site directory.
+    // Not using File API; a potential error must trigger a PHP warning.
+    chmod(DRUPAL_ROOT . '/' . $this->siteDirectory, 0777);
+
+    // During tests, cacheable responses should get the debugging cacheability
+    // headers by default.
+    $this->setContainerParameter('http.response.debug_cacheability_headers', TRUE);
+  }
+
+  /**
+   * Initialize various configurations post-installation.
+   *
+   * @param \Symfony\Component\DependencyInjection\ContainerInterface $container
+   *   The container.
+   */
+  protected function initConfig(ContainerInterface $container) {
+    $config = $container->get('config.factory');
+
+    // Manually create the private directory.
+    file_prepare_directory($this->privateFilesDirectory, FILE_CREATE_DIRECTORY);
+
+    // Manually configure the test mail collector implementation to prevent
+    // tests from sending out emails and collect them in state instead.
+    // While this should be enforced via settings.php prior to installation,
+    // some tests expect to be able to test mail system implementations.
+    $config->getEditable('system.mail')
+      ->set('interface.default', 'test_mail_collector')
+      ->save();
+
+    // By default, verbosely display all errors and disable all production
+    // environment optimizations for all tests to avoid needless overhead and
+    // ensure a sane default experience for test authors.
+    // @see https://www.drupal.org/node/2259167
+    $config->getEditable('system.logging')
+      ->set('error_level', 'verbose')
+      ->save();
+    $config->getEditable('system.performance')
+      ->set('css.preprocess', FALSE)
+      ->set('js.preprocess', FALSE)
+      ->save();
+
+    // Set an explicit time zone to not rely on the system one, which may vary
+    // from setup to setup. The Australia/Sydney time zone is chosen so all
+    // tests are run using an edge case scenario (UTC10 and DST). This choice
+    // is made to prevent time zone related regressions and reduce the
+    // fragility of the testing system in general.
+    $config->getEditable('system.date')
+      ->set('timezone.default', 'Australia/Sydney')
+      ->save();
+  }
+
+  /**
+   * Initializes user 1 for the site to be installed.
+   */
+  protected function initUserSession() {
+    $password = $this->randomMachineName();
+    // Define information about the user 1 account.
+    $this->rootUser = new UserSession([
+      'uid' => 1,
+      'name' => 'admin',
+      'mail' => '[e-mail]',
+      'pass_raw' => $password,
+      'passRaw' => $password,
+      'timezone' => date_default_timezone_get(),
+    ]);
+
+    // The child site derives its session name from the database prefix when
+    // running web tests.
+    $this->generateSessionName($this->databasePrefix);
+  }
+
+  /**
+   * Initializes the kernel after installation.
+   *
+   * @param \Symfony\Component\HttpFoundation\Request $request
+   *   Request object.
+   *
+   * @return \Symfony\Component\DependencyInjection\ContainerInterface
+   *   The container.
+   */
+  protected function initKernel(Request $request) {
+    $this->kernel = DrupalKernel::createFromRequest($request, $this->classLoader, 'prod', TRUE);
+    $this->kernel->prepareLegacyRequest($request);
+    // Force the container to be built from scratch instead of loaded from the
+    // disk. This forces us to not accidentally load the parent site.
+    return $this->kernel->rebuildContainer();
+  }
+
+  /**
+   * Install modules defined by `static::$modules`.
+   *
+   * To install test modules outside of the testing environment, add
+   * @code
+   * $settings['extension_discovery_scan_tests'] = TRUE;
+   * @endcode
+   * to your settings.php.
+   *
+   * @param \Symfony\Component\DependencyInjection\ContainerInterface $container
+   *   The container.
+   */
+  protected function installModulesFromClassProperty(ContainerInterface $container) {
+    $class = get_class($this);
+    $modules = [];
+    while ($class) {
+      if (property_exists($class, 'modules')) {
+        $modules = array_merge($modules, $class::$modules);
+      }
+      $class = get_parent_class($class);
+    }
+    if ($modules) {
+      $modules = array_unique($modules);
+      try {
+        $success = $container->get('module_installer')->install($modules, TRUE);
+        $this->assertTrue($success, SafeMarkup::format('Enabled modules: %modules', ['%modules' => implode(', ', $modules)]));
+      }
+      catch (MissingDependencyException $e) {
+        // The exception message has all the details.
+        $this->fail($e->getMessage());
+      }
+
+      $this->rebuildContainer();
+    }
+  }
+
+  /**
+   * Resets and rebuilds the environment after setup.
+   */
+  protected function rebuildAll() {
+    // Reset/rebuild all data structures after enabling the modules, primarily
+    // to synchronize all data structures and caches between the test runner and
+    // the child site.
+    // @see \Drupal\Core\DrupalKernel::bootCode()
+    // @todo Test-specific setUp() methods may set up further fixtures; find a
+    //   way to execute this after setUp() is done, or to eliminate it entirely.
+    $this->resetAll();
+    $this->kernel->prepareLegacyRequest(\Drupal::request());
+
+    // Explicitly call register() again on the container registered in \Drupal.
+    // @todo This should already be called through
+    //   DrupalKernel::prepareLegacyRequest() -> DrupalKernel::boot() but that
+    //   appears to be calling a different container.
+    $this->container->get('stream_wrapper_manager')->register();
+  }
+
+  /**
+   * Returns the parameters that will be used when Simpletest installs Drupal.
+   *
+   * @see install_drupal()
+   * @see install_state_defaults()
+   *
+   * @return array
+   *   Array of parameters for use in install_drupal().
+   */
+  protected function installParameters() {
+    $connection_info = Database::getConnectionInfo();
+    $driver = $connection_info['default']['driver'];
+    $connection_info['default']['prefix'] = $connection_info['default']['prefix']['default'];
+    unset($connection_info['default']['driver']);
+    unset($connection_info['default']['namespace']);
+    unset($connection_info['default']['pdo']);
+    unset($connection_info['default']['init_commands']);
+    // Remove database connection info that is not used by SQLite.
+    if ($driver === 'sqlite') {
+      unset($connection_info['default']['username']);
+      unset($connection_info['default']['password']);
+      unset($connection_info['default']['host']);
+      unset($connection_info['default']['port']);
+    }
+    $parameters = [
+      'interactive' => FALSE,
+      'parameters' => [
+        'profile' => $this->profile,
+        'langcode' => 'en',
+      ],
+      'forms' => [
+        'install_settings_form' => [
+          'driver' => $driver,
+          $driver => $connection_info['default'],
+        ],
+        'install_configure_form' => [
+          'site_name' => 'Drupal',
+          'site_mail' => '[e-mail]',
+          'account' => [
+            'name' => $this->rootUser->name,
+            'mail' => $this->rootUser->getEmail(),
+            'pass' => [
+              'pass1' => isset($this->rootUser->pass_raw) ? $this->rootUser->pass_raw : $this->rootUser->passRaw,
+              'pass2' => isset($this->rootUser->pass_raw) ? $this->rootUser->pass_raw : $this->rootUser->passRaw,
+            ],
+          ],
+          // form_type_checkboxes_value() requires NULL instead of FALSE values
+          // for programmatic form submissions to disable a checkbox.
+          'enable_update_status_module' => NULL,
+          'enable_update_status_emails' => NULL,
+        ],
+      ],
+    ];
+
+    // If we only have one db driver available, we cannot set the driver.
+    include_once DRUPAL_ROOT . '/core/includes/install.inc';
+    if (count($this->getDatabaseTypes()) == 1) {
+      unset($parameters['forms']['install_settings_form']['driver']);
+    }
+    return $parameters;
+  }
+
+  /**
+   * Sets up the base URL based upon the environment variable.
+   *
+   * @throws \Exception
+   *   Thrown when no SIMPLETEST_BASE_URL environment variable is provided.
+   */
+  protected function setupBaseUrl() {
+    global $base_url;
+
+    // Get and set the domain of the environment we are running our test
+    // coverage against.
+    $base_url = getenv('SIMPLETEST_BASE_URL');
+    if (!$base_url) {
+      throw new \Exception(
+        'You must provide a SIMPLETEST_BASE_URL environment variable to run some PHPUnit based functional tests.'
+      );
+    }
+
+    // Setup $_SERVER variable.
+    $parsed_url = parse_url($base_url);
+    $host = $parsed_url['host'] . (isset($parsed_url['port']) ? ':' . $parsed_url['port'] : '');
+    $path = isset($parsed_url['path']) ? rtrim(rtrim($parsed_url['path']), '/') : '';
+    $port = isset($parsed_url['port']) ? $parsed_url['port'] : 80;
+
+    $this->baseUrl = $base_url;
+
+    // If the passed URL schema is 'https' then setup the $_SERVER variables
+    // properly so that testing will run under HTTPS.
+    if ($parsed_url['scheme'] === 'https') {
+      $_SERVER['HTTPS'] = 'on';
+    }
+    $_SERVER['HTTP_HOST'] = $host;
+    $_SERVER['REMOTE_ADDR'] = '127.0.0.1';
+    $_SERVER['SERVER_ADDR'] = '127.0.0.1';
+    $_SERVER['SERVER_PORT'] = $port;
+    $_SERVER['SERVER_SOFTWARE'] = NULL;
+    $_SERVER['SERVER_NAME'] = 'localhost';
+    $_SERVER['REQUEST_URI'] = $path . '/';
+    $_SERVER['REQUEST_METHOD'] = 'GET';
+    $_SERVER['SCRIPT_NAME'] = $path . '/index.php';
+    $_SERVER['SCRIPT_FILENAME'] = $path . '/index.php';
+    $_SERVER['PHP_SELF'] = $path . '/index.php';
+    $_SERVER['HTTP_USER_AGENT'] = 'Drupal command line';
+  }
+
+  /**
+   * Prepares the current environment for running the test.
+   *
+   * Also sets up new resources for the testing environment, such as the public
+   * filesystem and configuration directories.
+   *
+   * This method is private as it must only be called once by
+   * BrowserTestBase::setUp() (multiple invocations for the same test would have
+   * unpredictable consequences) and it must not be callable or overridable by
+   * test classes.
+   */
+  protected function prepareEnvironment() {
+    // Bootstrap Drupal so we can use Drupal's built in functions.
+    $this->classLoader = require __DIR__ . '/../../../../../autoload.php';
+    $request = Request::createFromGlobals();
+    $kernel = TestRunnerKernel::createFromRequest($request, $this->classLoader);
+    // TestRunnerKernel expects the working directory to be DRUPAL_ROOT.
+    chdir(DRUPAL_ROOT);
+    $kernel->prepareLegacyRequest($request);
+    $this->prepareDatabasePrefix();
+
+    $this->originalSite = $kernel->findSitePath($request);
+
+    // Create test directory ahead of installation so fatal errors and debug
+    // information can be logged during installation process.
+    file_prepare_directory($this->siteDirectory, FILE_CREATE_DIRECTORY | FILE_MODIFY_PERMISSIONS);
+
+    // Prepare filesystem directory paths.
+    $this->publicFilesDirectory = $this->siteDirectory . '/files';
+    $this->privateFilesDirectory = $this->siteDirectory . '/private';
+    $this->tempFilesDirectory = $this->siteDirectory . '/temp';
+    $this->translationFilesDirectory = $this->siteDirectory . '/translations';
+
+    // Ensure the configImporter is refreshed for each test.
+    $this->configImporter = NULL;
+
+    // Unregister all custom stream wrappers of the parent site.
+    $wrappers = \Drupal::service('stream_wrapper_manager')->getWrappers(StreamWrapperInterface::ALL);
+    foreach ($wrappers as $scheme => $info) {
+      stream_wrapper_unregister($scheme);
+    }
+
+    // Reset statics.
+    drupal_static_reset();
+
+    $this->container = NULL;
+
+    // Unset globals.
+    unset($GLOBALS['config_directories']);
+    unset($GLOBALS['config']);
+    unset($GLOBALS['conf']);
+
+    // Log fatal errors.
+    ini_set('log_errors', 1);
+    ini_set('error_log', DRUPAL_ROOT . '/' . $this->siteDirectory . '/error.log');
+
+    // Change the database prefix.
+    $this->changeDatabasePrefix();
+
+    // After preparing the environment and changing the database prefix, we are
+    // in a valid test environment.
+    drupal_valid_test_ua($this->databasePrefix);
+
+    // Reset settings.
+    new Settings([
+      // For performance, simply use the database prefix as hash salt.
+      'hash_salt' => $this->databasePrefix,
+    ]);
+
+    drupal_set_time_limit($this->timeLimit);
+
+    // Save and clean the shutdown callbacks array because it is static cached
+    // and will be changed by the test run. Otherwise it will contain callbacks
+    // from both environments and the testing environment will try to call the
+    // handlers defined by the original one.
+    $callbacks = &drupal_register_shutdown_function();
+    $this->originalShutdownCallbacks = $callbacks;
+    $callbacks = [];
+  }
+
+  /**
+   * Returns all supported database driver installer objects.
+   *
+   * This wraps drupal_get_database_types() for use without a current container.
+   *
+   * @return \Drupal\Core\Database\Install\Tasks[]
+   *   An array of available database driver installer objects.
+   */
+  protected function getDatabaseTypes() {
+    if ($this->originalContainer) {
+      \Drupal::setContainer($this->originalContainer);
+    }
+    $database_types = drupal_get_database_types();
+    if ($this->originalContainer) {
+      \Drupal::unsetContainer();
+    }
+    return $database_types;
+  }
+
+}