Update to Drupal 8.0.0 beta 14. For more information, see https://drupal.org/node/2544542

core/lib/Drupal/Core/Access/AccessResult.php

@@ -25,6 +25,9 @@ use Drupal\Core\Session\AccountInterface;
  *
  * When using ::orIf() and ::andIf(), cacheability metadata will be merged
  * accordingly as well.
+ *
+ * @todo Use RefinableCacheableDependencyInterface and the corresponding trait in
+ *   https://www.drupal.org/node/2526326.
  */
 abstract class AccessResult implements AccessResultInterface, CacheableDependencyInterface {
 
@@ -316,10 +319,12 @@ abstract class AccessResult implements AccessResultInterface, CacheableDependenc
    *   The entity whose cache tag to set on the access result.
    *
    * @return $this
+   *
+   * @deprecated in Drupal 8.0.x-dev, will be removed before Drupal 9.0.0. Use
+   *   ::addCacheableDependency() instead.
    */
   public function cacheUntilEntityChanges(EntityInterface $entity) {
-    $this->addCacheTags($entity->getCacheTags());
-    return $this;
+    return $this->addCacheableDependency($entity);
   }
 
   /**
@@ -329,9 +334,33 @@ abstract class AccessResult implements AccessResultInterface, CacheableDependenc
    *   The configuration object whose cache tag to set on the access result.
    *
    * @return $this
+   *
+   * @deprecated in Drupal 8.0.x-dev, will be removed before Drupal 9.0.0. Use
+   *   ::addCacheableDependency() instead.
    */
   public function cacheUntilConfigurationChanges(ConfigBase $configuration) {
-    $this->addCacheTags($configuration->getCacheTags());
+    return $this->addCacheableDependency($configuration);
+  }
+
+  /**
+   * Adds a dependency on an object: merges its cacheability metadata.
+   *
+   * @param \Drupal\Core\Cache\CacheableDependencyInterface|object $other_object
+   *   The dependency. If the object implements CacheableDependencyInterface,
+   *   then its cacheability metadata will be used. Otherwise, the passed in
+   *   object must be assumed to be uncacheable, so max-age 0 is set.
+   *
+   * @return $this
+   */
+  public function addCacheableDependency($other_object) {
+    if ($other_object instanceof CacheableDependencyInterface) {
+      $this->contexts = Cache::mergeContexts($this->contexts, $other_object->getCacheContexts());
+      $this->tags = Cache::mergeTags($this->tags, $other_object->getCacheTags());
+      $this->maxAge = Cache::mergeMaxAges($this->maxAge, $other_object->getCacheMaxAge());
+    }
+    else {
+      $this->maxAge = 0;
+    }
     return $this;
   }
 

core/lib/Drupal/Core/Access/RouteProcessorCsrf.php

@@ -7,7 +7,7 @@
 
 namespace Drupal\Core\Access;
 
-use Drupal\Core\Cache\CacheableMetadata;
+use Drupal\Core\Render\BubbleableMetadata;
 use Drupal\Core\RouteProcessor\OutboundRouteProcessorInterface;
 use Symfony\Component\Routing\Route;
 
@@ -36,7 +36,7 @@ class RouteProcessorCsrf implements OutboundRouteProcessorInterface {
   /**
    * {@inheritdoc}
    */
-  public function processOutbound($route_name, Route $route, array &$parameters, CacheableMetadata $cacheable_metadata = NULL) {
+  public function processOutbound($route_name, Route $route, array &$parameters, BubbleableMetadata $bubbleable_metadata = NULL) {
     if ($route->hasRequirement('_csrf_token')) {
       $path = ltrim($route->getPath(), '/');
       // Replace the path parameters with values from the parameters array.
@@ -45,13 +45,44 @@ class RouteProcessorCsrf implements OutboundRouteProcessorInterface {
       }
       // Adding this to the parameters means it will get merged into the query
       // string when the route is compiled.
-      $parameters['token'] = $this->csrfToken->get($path);
-      if ($cacheable_metadata) {
-        // Tokens are per user and per session, so not cacheable.
-        // @todo Improve in https://www.drupal.org/node/2351015.
-        $cacheable_metadata->setCacheMaxAge(0);
+      if (!$bubbleable_metadata) {
+        $parameters['token'] = $this->csrfToken->get($path);
+      }
+      else {
+        // Generate a placeholder and a render array to replace it.
+        $placeholder = hash('sha1', $path);
+        $placeholder_render_array = [
+          '#lazy_builder' => ['route_processor_csrf:renderPlaceholderCsrfToken', [$path]],
+        ];
+
+        // Instead of setting an actual CSRF token as the query string, we set
+        // the placeholder, which will be replaced at the very last moment. This
+        // ensures links with CSRF tokens don't break cacheability.
+        $parameters['token'] = $placeholder;
+        $bubbleable_metadata->addAttachments(['placeholders' => [$placeholder => $placeholder_render_array]]);
       }
     }
   }
 
+  /**
+   * #lazy_builder callback; gets a CSRF token for the given path.
+   *
+   * @param string $path
+   *   The path to get a CSRF token for.
+   *
+   * @return array
+   *   A renderable array representing the CSRF token.
+   */
+  public function renderPlaceholderCsrfToken($path) {
+    return [
+      '#markup' => $this->csrfToken->get($path),
+      // Tokens are per session.
+      '#cache' => [
+        'contexts' => [
+          'session',
+        ],
+      ],
+    ];
+  }
+
 }

core/lib/Drupal/Core/Ajax/AjaxResponseAttachmentsProcessor.php

@@ -164,15 +164,15 @@ class AjaxResponseAttachmentsProcessor implements AttachmentsResponseProcessorIn
     $resource_commands = array();
     if ($css_assets) {
       $css_render_array = $this->cssCollectionRenderer->render($css_assets);
-      $resource_commands[] = new AddCssCommand($this->renderer->renderPlain($css_render_array));
+      $resource_commands[] = new AddCssCommand((string) $this->renderer->renderPlain($css_render_array));
     }
     if ($js_assets_header) {
       $js_header_render_array = $this->jsCollectionRenderer->render($js_assets_header);
-      $resource_commands[] = new PrependCommand('head', $this->renderer->renderPlain($js_header_render_array));
+      $resource_commands[] = new PrependCommand('head', (string) $this->renderer->renderPlain($js_header_render_array));
     }
     if ($js_assets_footer) {
       $js_footer_render_array = $this->jsCollectionRenderer->render($js_assets_footer);
-      $resource_commands[] = new AppendCommand('body', $this->renderer->renderPlain($js_footer_render_array));
+      $resource_commands[] = new AppendCommand('body', (string) $this->renderer->renderPlain($js_footer_render_array));
     }
     foreach (array_reverse($resource_commands) as $resource_command) {
       $response->addCommand($resource_command, TRUE);

core/lib/Drupal/Core/Ajax/CommandWithAttachedAssetsTrait.php

@@ -37,10 +37,10 @@ trait CommandWithAttachedAssetsTrait {
     if (is_array($this->content)) {
       $html = \Drupal::service('renderer')->renderRoot($this->content);
       $this->attachedAssets = AttachedAssets::createFromRenderArray($this->content);
-      return $html;
+      return (string) $html;
     }
     else {
-      return $this->content;
+      return (string) $this->content;
     }
   }
 

core/lib/Drupal/Core/Authentication/AuthenticationCollector.php

@@ -0,0 +1,89 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\Core\Authentication\AuthenticationCollector.
+ */
+
+namespace Drupal\Core\Authentication;
+
+/**
+ * A collector class for authentication providers.
+ */
+class AuthenticationCollector implements AuthenticationCollectorInterface {
+
+  /**
+   * Array of all registered authentication providers, keyed by ID.
+   *
+   * @var \Drupal\Core\Authentication\AuthenticationProviderInterface[]
+   */
+  protected $providers;
+
+  /**
+   * Array of all providers and their priority.
+   *
+   * @var array
+   */
+  protected $providerOrders = [];
+
+  /**
+   * Sorted list of registered providers.
+   *
+   * @var \Drupal\Core\Authentication\AuthenticationProviderInterface[]
+   */
+  protected $sortedProviders;
+
+  /**
+   * List of providers which are allowed on routes with no _auth option.
+   *
+   * @var string[]
+   */
+  protected $globalProviders;
+
+  /**
+   * {@inheritdoc}
+   */
+  public function addProvider(AuthenticationProviderInterface $provider, $provider_id, $priority = 0, $global = FALSE) {
+    $this->providers[$provider_id] = $provider;
+    $this->providerOrders[$priority][$provider_id] = $provider;
+    // Force the providers to be re-sorted.
+    $this->sortedProviders = NULL;
+
+    if ($global) {
+      $this->globalProviders[$provider_id] = TRUE;
+    }
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function isGlobal($provider_id) {
+    return isset($this->globalProviders[$provider_id]);
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function getProvider($provider_id) {
+    return isset($this->providers[$provider_id]) ? $this->providers[$provider_id] : NULL;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function getSortedProviders() {
+    if (!isset($this->sortedProviders)) {
+      // Sort the providers according to priority.
+      krsort($this->providerOrders);
+
+      // Merge nested providers from $this->providers into $this->sortedProviders.
+      $this->sortedProviders = [];
+      foreach ($this->providerOrders as $providers) {
+        $this->sortedProviders = array_merge($this->sortedProviders, $providers);
+      }
+    }
+
+    return $this->sortedProviders;
+  }
+
+}

core/lib/Drupal/Core/Authentication/AuthenticationCollectorInterface.php

@@ -0,0 +1,62 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\Core\Authentication\AuthenticationCollectorInterface.
+ */
+
+namespace Drupal\Core\Authentication;
+
+/**
+ * Interface for collectors of registered authentication providers.
+ */
+interface AuthenticationCollectorInterface {
+
+  /**
+   * Adds a provider to the array of registered providers.
+   *
+   * @param \Drupal\Core\Authentication\AuthenticationProviderInterface $provider
+   *   The provider object.
+   * @param string $provider_id
+   *   Identifier of the provider.
+   * @param int $priority
+   *   (optional) The provider's priority.
+   * @param bool $global
+   *   (optional) TRUE if the provider is to be applied globally on all routes.
+   *   Defaults to FALSE.
+   */
+  public function addProvider(AuthenticationProviderInterface $provider, $provider_id, $priority = 0, $global = FALSE);
+
+  /**
+   * Returns whether a provider is considered global.
+   *
+   * @param string $provider_id
+   *   The provider ID.
+   *
+   * @return bool
+   *   TRUE if the provider is global, FALSE otherwise.
+   *
+   * @see \Drupal\Core\Authentication\AuthenticationCollectorInterface::addProvider
+   */
+  public function isGlobal($provider_id);
+
+  /**
+   * Returns an authentication provider.
+   *
+   * @param string $provider_id
+   *   The provider ID.
+   *
+   * @return \Drupal\Core\Authentication\AuthenticationProviderInterface|NULL
+   *   The authentication provider which matches the ID.
+   */
+  public function getProvider($provider_id);
+
+  /**
+   * Returns the sorted array of authentication providers.
+   *
+   * @return \Drupal\Core\Authentication\AuthenticationProviderInterface[]
+   *   An array of authentication provider objects.
+   */
+  public function getSortedProviders();
+
+}

core/lib/Drupal/Core/Authentication/AuthenticationManager.php

@@ -20,69 +20,23 @@ use Symfony\Component\HttpFoundation\Request;
  *
  * If no provider set an active user then the user is set to anonymous.
  */
-class AuthenticationManager implements AuthenticationProviderInterface, AuthenticationProviderFilterInterface, AuthenticationProviderChallengeInterface, AuthenticationManagerInterface {
+class AuthenticationManager implements AuthenticationProviderInterface, AuthenticationProviderFilterInterface, AuthenticationProviderChallengeInterface {
 
   /**
-   * Array of all registered authentication providers, keyed by ID.
+   * The authentication provider collector.
    *
-   * @var \Drupal\Core\Authentication\AuthenticationProviderInterface[]
+   * @var \Drupal\Core\Authentication\AuthenticationCollectorInterface
    */
-  protected $providers;
+  protected $authCollector;
 
   /**
-   * Array of all providers and their priority.
+   * Creates a new authentication manager instance.
    *
-   * @var array
+   * @param \Drupal\Core\Authentication\AuthenticationCollectorInterface $auth_collector
+   *   The authentication provider collector.
    */
-  protected $providerOrders = array();
-
-  /**
-   * Sorted list of registered providers.
-   *
-   * @var \Drupal\Core\Authentication\AuthenticationProviderInterface[]
-   */
-  protected $sortedProviders;
-
-  /**
-   * List of providers which implement the filter interface.
-   *
-   * @var \Drupal\Core\Authentication\AuthenticationProviderFilterInterface[]
-   */
-  protected $filters;
-
-  /**
-   * List of providers which implement the challenge interface.
-   *
-   * @var \Drupal\Core\Authentication\AuthenticationProviderChallengeInterface[]
-   */
-  protected $challengers;
-
-  /**
-   * List of providers which are allowed on routes with no _auth option.
-   *
-   * @var string[]
-   */
-  protected $globalProviders;
-
-  /**
-   * {@inheritdoc}
-   */
-  public function addProvider(AuthenticationProviderInterface $provider, $provider_id, $priority = 0, $global = FALSE) {
-    $this->providers[$provider_id] = $provider;
-    $this->providerOrders[$priority][$provider_id] = $provider;
-    // Force the builders to be re-sorted.
-    $this->sortedProviders = NULL;
-
-    if ($provider instanceof AuthenticationProviderFilterInterface) {
-      $this->filters[$provider_id] = $provider;
-    }
-    if ($provider instanceof AuthenticationProviderChallengeInterface) {
-      $this->challengers[$provider_id] = $provider;
-    }
-
-    if ($global) {
-      $this->globalProviders[$provider_id] = TRUE;
-    }
+  public function __construct(AuthenticationCollectorInterface $auth_collector) {
+    $this->authCollector = $auth_collector;
   }
 
   /**
@@ -97,7 +51,13 @@ class AuthenticationManager implements AuthenticationProviderInterface, Authenti
    */
   public function authenticate(Request $request) {
     $provider_id = $this->getProvider($request);
-    return $this->providers[$provider_id]->authenticate($request);
+    $provider = $this->authCollector->getProvider($provider_id);
+
+    if ($provider) {
+      return $provider->authenticate($request);
+    }
+
+    return NULL;
   }
 
   /**
@@ -110,7 +70,7 @@ class AuthenticationManager implements AuthenticationProviderInterface, Authenti
       $result = $this->applyFilter($request, $authenticated, $this->getProvider($request));
     }
     else {
-      foreach ($this->getSortedProviders() as $provider_id => $provider) {
+      foreach ($this->authCollector->getSortedProviders() as $provider_id => $provider) {
         if ($this->applyFilter($request, $authenticated, $provider_id)) {
           $result = TRUE;
           break;
@@ -126,8 +86,10 @@ class AuthenticationManager implements AuthenticationProviderInterface, Authenti
    */
   public function challengeException(Request $request, \Exception $previous) {
     $provider_id = $this->getChallenger($request);
+
     if ($provider_id) {
-      return $this->challengers[$provider_id]->challengeException($request, $previous);
+      $provider = $this->authCollector->getProvider($provider_id);
+      return $provider->challengeException($request, $previous);
     }
   }
 
@@ -142,7 +104,7 @@ class AuthenticationManager implements AuthenticationProviderInterface, Authenti
    *   If no application detects appropriate credentials, then NULL is returned.
    */
   protected function getProvider(Request $request) {
-    foreach ($this->getSortedProviders() as $provider_id => $provider) {
+    foreach ($this->authCollector->getSortedProviders() as $provider_id => $provider) {
       if ($provider->applies($request)) {
         return $provider_id;
       }
@@ -150,21 +112,19 @@ class AuthenticationManager implements AuthenticationProviderInterface, Authenti
   }
 
   /**
-   * Returns the id of the challenge provider for a request.
+   * Returns the ID of the challenge provider for a request.
    *
    * @param \Symfony\Component\HttpFoundation\Request $request
    *   The incoming request.
    *
    * @return string|NULL
-   *   The id of the first authentication provider which applies to the request.
+   *   The ID of the first authentication provider which applies to the request.
    *   If no application detects appropriate credentials, then NULL is returned.
    */
   protected function getChallenger(Request $request) {
-    if (!empty($this->challengers)) {
-      foreach ($this->getSortedProviders($request, FALSE) as $provider_id => $provider) {
-        if (isset($this->challengers[$provider_id]) && !$provider->applies($request) && $this->applyFilter($request, FALSE, $provider_id)) {
-          return $provider_id;
-        }
+    foreach ($this->authCollector->getSortedProviders() as $provider_id => $provider) {
+      if (($provider instanceof AuthenticationProviderChallengeInterface) && !$provider->applies($request) && $this->applyFilter($request, FALSE, $provider_id)) {
+        return $provider_id;
       }
     }
   }
@@ -186,8 +146,10 @@ class AuthenticationManager implements AuthenticationProviderInterface, Authenti
    *   TRUE if provider is allowed, FALSE otherwise.
    */
   protected function applyFilter(Request $request, $authenticated, $provider_id) {
-    if (isset($this->filters[$provider_id])) {
-      $result = $this->filters[$provider_id]->appliesToRoutedRequest($request, $authenticated);
+    $provider = $this->authCollector->getProvider($provider_id);
+
+    if ($provider && ($provider instanceof AuthenticationProviderFilterInterface)) {
+      $result = $provider->appliesToRoutedRequest($request, $authenticated);
     }
     else {
       $result = $this->defaultFilter($request, $provider_id);
@@ -222,27 +184,8 @@ class AuthenticationManager implements AuthenticationProviderInterface, Authenti
       return in_array($provider_id, $route->getOption('_auth'));
     }
     else {
-      return isset($this->globalProviders[$provider_id]);
+      return $this->authCollector->isGlobal($provider_id);
     }
   }
 
-  /**
-   * Returns the sorted array of authentication providers.
-   *
-   * @return \Drupal\Core\Authentication\AuthenticationProviderInterface[]
-   *   An array of authentication provider objects.
-   */
-  protected function getSortedProviders() {
-    if (!isset($this->sortedProviders)) {
-      // Sort the builders according to priority.
-      krsort($this->providerOrders);
-      // Merge nested providers from $this->providers into $this->sortedProviders.
-      $this->sortedProviders = array();
-      foreach ($this->providerOrders as $providers) {
-        $this->sortedProviders = array_merge($this->sortedProviders, $providers);
-      }
-    }
-    return $this->sortedProviders;
-  }
-
 }

core/lib/Drupal/Core/Authentication/AuthenticationManagerInterface.php

@@ -1,30 +0,0 @@
-<?php
-
-/**
- * @file
- * Contains \Drupal\Core\Authentication\AuthenticationManagerInterface.
- */
-
-namespace Drupal\Core\Authentication;
-
-/**
- * Defines an interface for authentication managers.
- */
-interface AuthenticationManagerInterface {
-
-  /**
-   * Adds a provider to the array of registered providers.
-   *
-   * @param \Drupal\Core\Authentication\AuthenticationProviderInterface $provider
-   *   The provider object.
-   * @param string $provider_id
-   *   Identifier of the provider.
-   * @param int $priority
-   *   (optional) The provider's priority.
-   * @param bool $global
-   *   (optional) TRUE if the provider is to be applied globally on all routes.
-   *   Defaults to FALSE.
-   */
-  public function addProvider(AuthenticationProviderInterface $provider, $provider_id, $priority = 0, $global = FALSE);
-
-}

core/lib/Drupal/Core/Block/BlockBase.php

@@ -10,6 +10,7 @@ namespace Drupal\Core\Block;
 use Drupal\block\BlockInterface;
 use Drupal\Component\Utility\SafeMarkup;
 use Drupal\Core\Access\AccessResult;
+use Drupal\Core\Cache\CacheableDependencyInterface;
 use Drupal\Core\Form\FormStateInterface;
 use Drupal\Core\Plugin\ContextAwarePluginBase;
 use Drupal\Component\Utility\Unicode;
@@ -265,18 +266,23 @@ abstract class BlockBase extends ContextAwarePluginBase implements BlockPluginIn
     //   \Drupal\system\MachineNameController::transliterate(), so it might make
     //   sense to provide a common service for the two.
     $transliterated = $this->transliteration()->transliterate($admin_label, LanguageInterface::LANGCODE_DEFAULT, '_');
-
-    $replace_pattern = '[^a-z0-9_.]+';
-
     $transliterated = Unicode::strtolower($transliterated);
 
-    if (isset($replace_pattern)) {
-      $transliterated = preg_replace('@' . $replace_pattern . '@', '', $transliterated);
-    }
+    $transliterated = preg_replace('@[^a-z0-9_.]+@', '', $transliterated);
 
     return $transliterated;
   }
 
+  /**
+   * {@inheritdoc}
+   */
+  public function getCacheMaxAge() {
+    $max_age = parent::getCacheMaxAge();
+    // @todo Configurability of this will be removed in
+    //   https://www.drupal.org/node/2458763.
+    return Cache::mergeMaxAges($max_age, (int) $this->configuration['cache']['max_age']);
+  }
+
   /**
    * Wraps the transliteration service.
    *
@@ -299,25 +305,4 @@ abstract class BlockBase extends ContextAwarePluginBase implements BlockPluginIn
     $this->transliteration = $transliteration;
   }
 
-  /**
-   * {@inheritdoc}
-   */
-  public function getCacheContexts() {
-    return [];
-  }
-
-  /**
-   * {@inheritdoc}
-   */
-  public function getCacheTags() {
-    return [];
-  }
-
-  /**
-   * {@inheritdoc}
-   */
-  public function getCacheMaxAge() {
-    return (int)$this->configuration['cache']['max_age'];
-  }
-
 }

core/lib/Drupal/Core/Breadcrumb/BreadcrumbManager.php

@@ -7,7 +7,6 @@
 
 namespace Drupal\Core\Breadcrumb;
 
-use Drupal\Component\Utility\SafeMarkup;
 use Drupal\Core\Extension\ModuleHandlerInterface;
 use Drupal\Core\Routing\RouteMatchInterface;
 
@@ -95,7 +94,7 @@ class BreadcrumbManager implements ChainBreadcrumbBuilderInterface {
         break;
       }
       else {
-        throw new \UnexpectedValueException(SafeMarkup::format('Invalid breadcrumb returned by !class::build().', array('!class' => get_class($builder))));
+        throw new \UnexpectedValueException('Invalid breadcrumb returned by ' . get_class($builder) . '::build().');
       }
     }
     // Allow modules to alter the breadcrumb.

core/lib/Drupal/Core/Cache/Cache.php

@@ -24,19 +24,16 @@ class Cache {
   /**
    * Merges arrays of cache contexts and removes duplicates.
    *
-   * @param string[] …
-   *   Arrays of cache contexts to merge.
+   * @param array $a
+   *    Cache contexts array to merge.
+   * @param array $b
+   *    Cache contexts array to merge.
    *
    * @return string[]
    *   The merged array of cache contexts.
    */
-  public static function mergeContexts() {
-    $cache_context_arrays = func_get_args();
-    $cache_contexts = [];
-    foreach ($cache_context_arrays as $contexts) {
-      $cache_contexts = array_merge($cache_contexts, $contexts);
-    }
-    $cache_contexts = array_unique($cache_contexts);
+  public static function mergeContexts(array $a = [], array $b = []) {
+    $cache_contexts = array_unique(array_merge($a, $b));
     \Drupal::service('cache_contexts_manager')->validateTokens($cache_contexts);
     sort($cache_contexts);
     return $cache_contexts;
@@ -53,19 +50,16 @@ class Cache {
    * allows items to be invalidated based on all tags attached to the content
    * they're constituted from.
    *
-   * @param string[] …
-   *   Arrays of cache tags to merge.
+   * @param array $a
+   *    Cache tags array to merge.
+   * @param array $b
+   *    Cache tags array to merge.
    *
    * @return string[]
    *   The merged array of cache tags.
    */
-  public static function mergeTags() {
-    $cache_tag_arrays = func_get_args();
-    $cache_tags = [];
-    foreach ($cache_tag_arrays as $tags) {
-      $cache_tags = array_merge($cache_tags, $tags);
-    }
-    $cache_tags = array_unique($cache_tags);
+  public static function mergeTags(array $a = [], array $b = []) {
+    $cache_tags = array_unique(array_merge($a, $b));
     static::validateTags($cache_tags);
     sort($cache_tags);
     return $cache_tags;
@@ -76,29 +70,25 @@ class Cache {
    *
    * Ensures infinite max-age (Cache::PERMANENT) is taken into account.
    *
-   * @param int …
-   *   Max-age values.
+   * @param int $a
+   *    Max age value to merge.
+   * @param int $b
+   *    Max age value to merge.
    *
    * @return int
    *   The minimum max-age value.
    */
-  public static function mergeMaxAges() {
-    $max_ages = func_get_args();
-
-    // Filter out all max-age values set to cache permanently.
-    if (in_array(Cache::PERMANENT, $max_ages)) {
-      $max_ages = array_filter($max_ages, function ($max_age) {
-        return $max_age !== Cache::PERMANENT;
-      });
-
-      // If nothing is left, then all max-age values were set to cache
-      // permanently, and then that is the result.
-      if (empty($max_ages)) {
-        return Cache::PERMANENT;
-      }
+  public static function mergeMaxAges($a = Cache::PERMANENT, $b = Cache::PERMANENT) {
+    // If one of the values is Cache::PERMANENT, return the other value.
+    if ($a === Cache::PERMANENT){
+      return $b;
+    }
+    if ($b === Cache::PERMANENT){
+      return $a;
     }
 
-    return min($max_ages);
+    // If none or the values are Cache::PERMANENT, return the minimum value.
+    return min($a, $b);
   }
 
   /**

core/lib/Drupal/Core/Cache/CacheableMetadata.php

@@ -10,6 +10,9 @@ namespace Drupal\Core\Cache;
  * Defines a generic class for passing cacheability metadata.
  *
  * @ingroup cache
+ *
+ * @todo Use RefinableCacheableDependencyInterface and the corresponding trait in
+ *   https://www.drupal.org/node/2526326.
  */
 class CacheableMetadata implements CacheableDependencyInterface {
 
@@ -129,6 +132,35 @@ class CacheableMetadata implements CacheableDependencyInterface {
     return $this;
   }
 
+  /**
+   * Adds a dependency on an object: merges its cacheability metadata.
+   *
+   * @param \Drupal\Core\Cache\CacheableDependencyInterface|mixed $other_object
+   *   The dependency. If the object implements CacheableDependencyInterface,
+   *   then its cacheability metadata will be used. Otherwise, the passed in
+   *   object must be assumed to be uncacheable, so max-age 0 is set.
+   *
+   * @return $this
+   */
+  public function addCacheableDependency($other_object) {
+    if ($other_object instanceof CacheableDependencyInterface) {
+      $this->addCacheTags($other_object->getCacheTags());
+      $this->addCacheContexts($other_object->getCacheContexts());
+      if ($this->maxAge === Cache::PERMANENT) {
+        $this->maxAge = $other_object->getCacheMaxAge();
+      }
+      elseif (($max_age = $other_object->getCacheMaxAge()) && $max_age !== Cache::PERMANENT) {
+        $this->maxAge = Cache::mergeMaxAges($this->maxAge, $max_age);
+      }
+    }
+    else {
+      // Not a cacheable dependency, this can not be cached.
+      $this->maxAge = 0;
+    }
+
+    return $this;
+  }
+
   /**
    * Merges the values of another CacheableMetadata object with this one.
    *
@@ -139,7 +171,7 @@ class CacheableMetadata implements CacheableDependencyInterface {
    *   A new CacheableMetadata object, with the merged data.
    */
   public function merge(CacheableMetadata $other) {
-    $result = new static();
+    $result = clone $this;
 
     // This is called many times per request, so avoid merging unless absolutely
     // necessary.

core/lib/Drupal/Core/Cache/Context/AccountPermissionsCacheContext.php

@@ -7,18 +7,21 @@
 
 namespace Drupal\Core\Cache\Context;
 
+use Drupal\Core\Cache\CacheableMetadata;
 use Drupal\Core\Session\AccountInterface;
 use Drupal\Core\Session\PermissionsHashGeneratorInterface;
 
 /**
  * Defines the AccountPermissionsCacheContext service, for "per permission" caching.
+ *
+ * Cache context ID: 'user.permissions'.
  */
-class AccountPermissionsCacheContext extends UserCacheContext {
+class AccountPermissionsCacheContext extends UserCacheContextBase implements CacheContextInterface {
 
   /**
    * The permissions hash generator.
    *
-   * @var \Drupal\user\PermissionsHashInterface
+   * @var \Drupal\Core\Session\PermissionsHashGeneratorInterface
    */
   protected $permissionsHashGenerator;
 
@@ -27,7 +30,7 @@ class AccountPermissionsCacheContext extends UserCacheContext {
    *
    * @param \Drupal\Core\Session\AccountInterface $user
    *   The current user.
-   * @param \Drupal\user\PermissionsHashInterface $permissions_hash_generator
+   * @param \Drupal\Core\Session\PermissionsHashGeneratorInterface $permissions_hash_generator
    *   The permissions hash generator.
    */
   public function __construct(AccountInterface $user, PermissionsHashGeneratorInterface $permissions_hash_generator) {
@@ -46,7 +49,24 @@ class AccountPermissionsCacheContext extends UserCacheContext {
    * {@inheritdoc}
    */
   public function getContext() {
-    return 'ph.' . $this->permissionsHashGenerator->generate($this->user);
+    return $this->permissionsHashGenerator->generate($this->user);
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function getCacheableMetadata() {
+    $cacheable_metadata = new CacheableMetadata();
+
+    // The permissions hash changes when:
+    // - a user is updated to have different roles;
+    $tags = ['user:' . $this->user->id()];
+    // - a role is updated to have different permissions.
+    foreach ($this->user->getRoles() as $rid) {
+      $tags[] = "config:user.role.$rid";
+    }
+
+    return $cacheable_metadata->setCacheTags($tags);
   }
 
 }

core/lib/Drupal/Core/Cache/Context/CacheContextInterface.php

@@ -31,4 +31,21 @@ interface CacheContextInterface {
    */
   public function getContext();
 
+  /**
+   * Gets the cacheability metadata for the context.
+   *
+   * There are three valid cases for the returned CacheableMetadata object:
+   * - An empty object means this can be optimized away safely.
+   * - A max-age of 0 means that this context can never be optimized away. It
+   *   will never bubble up and cache tags will not be used.
+   * - Any non-zero max-age and cache tags will bubble up into the cache item
+   *   if this is optimized away to allow for invalidation if the context
+   *   value changes.
+   *
+   *
+   * @return \Drupal\Core\Cache\CacheableMetadata
+   *   A cacheable metadata object.
+   */
+  public function getCacheableMetadata();
+
 }

core/lib/Drupal/Core/Cache/Context/CacheContextsManager.php

@@ -7,7 +7,7 @@
 
 namespace Drupal\Core\Cache\Context;
 
-use Drupal\Component\Utility\SafeMarkup;
+use Drupal\Core\Cache\CacheableMetadata;
 use Symfony\Component\DependencyInjection\ContainerInterface;
 
 /**
@@ -99,23 +99,35 @@ class CacheContextsManager {
    * @param string[] $context_tokens
    *   An array of cache context tokens.
    *
-   * @return string[]
-   *   The array of corresponding cache keys.
+   * @return \Drupal\Core\Cache\Context\ContextCacheKeys
+   *   The ContextCacheKeys object containing the converted cache keys and
+   *   cacheability metadata.
    *
-   * @throws \InvalidArgumentException
+   * @throws \LogicException
+   *   Thrown if any of the context tokens or parameters are not valid.
    */
   public function convertTokensToKeys(array $context_tokens) {
-    $context_tokens = $this->optimizeTokens($context_tokens);
-    sort($context_tokens);
-    $keys = [];
-    foreach (static::parseTokens($context_tokens) as $context) {
-      list($context_id, $parameter) = $context;
-      if (!in_array($context_id, $this->contexts)) {
-        throw new \InvalidArgumentException(SafeMarkup::format('"@context" is not a valid cache context ID.', ['@context' => $context_id]));
-      }
-      $keys[] = $this->getService($context_id)->getContext($parameter);
+    $this->validateTokens($context_tokens);
+    $cacheable_metadata = new CacheableMetadata();
+    $optimized_tokens = $this->optimizeTokens($context_tokens);
+    // Iterate over cache contexts that have been optimized away and get their
+    // cacheability metadata.
+    foreach (static::parseTokens(array_diff($context_tokens, $optimized_tokens)) as $context_token) {
+      list($context_id, $parameter) = $context_token;
+      $context = $this->getService($context_id);
+      $cacheable_metadata = $cacheable_metadata->merge($context->getCacheableMetadata($parameter));
     }
-    return $keys;
+
+    sort($optimized_tokens);
+    $keys = [];
+    foreach (array_combine($optimized_tokens, static::parseTokens($optimized_tokens)) as $context_token => $context) {
+      list($context_id, $parameter) = $context;
+      $keys[] = '[' . $context_token . ']=' . $this->getService($context_id)->getContext($parameter);
+    }
+
+    // Create the returned object and merge in the cacheability metadata.
+    $context_cache_keys = new ContextCacheKeys($keys);
+    return $context_cache_keys->merge($cacheable_metadata);
   }
 
   /**
@@ -129,6 +141,9 @@ class CacheContextsManager {
    * possible of a set of cache context tokens, that still captures the entire
    * universe of variations.
    *
+   * If a cache context is being optimized away, it is able to set cacheable
+   * metadata for itself which will be bubbled up.
+   *
    * E.g. when caching per user ('user'), also caching per role ('user.roles')
    * is meaningless because "per role" is implied by "per user".
    *
@@ -150,6 +165,14 @@ class CacheContextsManager {
   public function optimizeTokens(array $context_tokens) {
     $optimized_content_tokens = [];
     foreach ($context_tokens as $context_token) {
+
+      // Extract the parameter if available.
+      $parameter = NULL;
+      $context_id = $context_token;
+      if (strpos($context_token, ':') !== FALSE) {
+        list($context_id, $parameter) = explode(':', $context_token);
+      }
+
       // Context tokens without:
       // - a period means they don't have a parent
       // - a colon means they're not a specific value of a cache context
@@ -157,6 +180,11 @@ class CacheContextsManager {
       if (strpos($context_token, '.') === FALSE && strpos($context_token, ':') === FALSE) {
         $optimized_content_tokens[] = $context_token;
       }
+      // Check cacheability. If the context defines a max-age of 0, then it
+      // can not be optimized away. Pass the parameter along if we have one.
+      elseif ($this->getService($context_id)->getCacheableMetadata($parameter)->getCacheMaxAge() === 0) {
+        $optimized_content_tokens[] = $context_token;
+      }
       // The context token has a period or a colon. Iterate over all ancestor
       // cache contexts. If one exists, omit the context token.
       else {

core/lib/Drupal/Core/Cache/Context/CalculatedCacheContextInterface.php

@@ -34,7 +34,32 @@ interface CalculatedCacheContextInterface {
    * @return string
    *   The string representation of the cache context. When $parameter is NULL,
    *   a value representing all possible parameters must be generated.
+   *
+   * @throws \LogicException
+   *   Thrown if the passed in parameter is invalid.
    */
   public function getContext($parameter = NULL);
 
+  /**
+   * Gets the cacheability metadata for the context based on the parameter value.
+   *
+   * There are three valid cases for the returned CacheableMetadata object:
+   * - An empty object means this can be optimized away safely.
+   * - A max-age of 0 means that this context can never be optimized away. It
+   *   will never bubble up and cache tags will not be used.
+   * - Any non-zero max-age and cache tags will bubble up into the cache item
+   *   if this is optimized away to allow for invalidation if the context
+   *   value changes.
+   *
+   * @param string|null $parameter
+   *   The parameter, or NULL to indicate all possible parameter values.
+   *
+   * @return \Drupal\Core\Cache\CacheableMetadata
+   *   A cacheable metadata object.
+   *
+   * @throws \LogicException
+   *   Thrown if the passed in parameter is invalid.
+   */
+  public function getCacheableMetadata($parameter = NULL);
+
 }

core/lib/Drupal/Core/Cache/Context/ContextCacheKeys.php

@@ -0,0 +1,44 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\Core\Cache\Context\ContextCacheKeys.
+ */
+
+namespace Drupal\Core\Cache\Context;
+
+use Drupal\Core\Cache\CacheableMetadata;
+
+/**
+ * A value object to store generated cache keys with its cacheability metadata.
+ */
+class ContextCacheKeys extends CacheableMetadata {
+
+  /**
+   * The generated cache keys.
+   *
+   * @var string[]
+   */
+  protected $keys;
+
+  /**
+   * Constructs a ContextCacheKeys object.
+   *
+   * @param string[] $keys
+   *   The cache context keys.
+   */
+  public function __construct(array $keys) {
+    $this->keys = $keys;
+  }
+
+  /**
+   * Gets the generated cache keys.
+   *
+   * @return string[]
+   *   The cache keys.
+   */
+  public function getKeys() {
+    return $this->keys;
+  }
+
+}

core/lib/Drupal/Core/Cache/Context/CookiesCacheContext.php

@@ -7,8 +7,14 @@
 
 namespace Drupal\Core\Cache\Context;
 
+use Drupal\Core\Cache\CacheableMetadata;
+
 /**
  * Defines the CookiesCacheContext service, for "per cookie" caching.
+ *
+ * Cache context ID: 'cookies' (to vary by all cookies).
+ * Calculated cache context ID: 'cookies:%name', e.g. 'cookies:device_type' (to
+ * vary by the 'device_type' cookie).
  */
 class CookiesCacheContext extends RequestStackCacheContextBase implements CalculatedCacheContextInterface {
 
@@ -31,4 +37,11 @@ class CookiesCacheContext extends RequestStackCacheContextBase implements Calcul
     }
   }
 
+  /**
+   * {@inheritdoc}
+   */
+  public function getCacheableMetadata($cookie = NULL) {
+    return new CacheableMetadata();
+  }
+
 }

core/lib/Drupal/Core/Cache/Context/HeadersCacheContext.php

@@ -7,8 +7,14 @@
 
 namespace Drupal\Core\Cache\Context;
 
+use Drupal\Core\Cache\CacheableMetadata;
+
 /**
  * Defines the HeadersCacheContext service, for "per header" caching.
+ *
+ * Cache context ID: 'headers' (to vary by all headers).
+ * Calculated cache context ID: 'headers:%name', e.g. 'headers:X-Something' (to
+ * vary by the 'X-Something' header).
  */
 class HeadersCacheContext extends RequestStackCacheContextBase implements CalculatedCacheContextInterface {
 
@@ -31,4 +37,11 @@ class HeadersCacheContext extends RequestStackCacheContextBase implements Calcul
     }
   }
 
+  /**
+   * {@inheritdoc}
+   */
+  public function getCacheableMetadata($header = NULL) {
+    return new CacheableMetadata();
+  }
+
 }

core/lib/Drupal/Core/Cache/Context/IpCacheContext.php

@@ -7,10 +7,14 @@
 
 namespace Drupal\Core\Cache\Context;
 
+use Drupal\Core\Cache\CacheableMetadata;
+
 /**
  * Defines the IpCacheContext service, for "per IP address" caching.
+ *
+ * Cache context ID: 'ip'.
  */
-class IpCacheContext extends RequestStackCacheContextBase {
+class IpCacheContext extends RequestStackCacheContextBase implements CacheContextInterface {
 
   /**
    * {@inheritdoc}
@@ -26,4 +30,11 @@ class IpCacheContext extends RequestStackCacheContextBase {
     return $this->requestStack->getCurrentRequest()->getClientIp();
   }
 
+  /**
+   * {@inheritdoc}
+   */
+  public function getCacheableMetadata() {
+    return new CacheableMetadata();
+  }
+
 }

core/lib/Drupal/Core/Cache/Context/IsSuperUserCacheContext.php

@@ -7,10 +7,14 @@
 
 namespace Drupal\Core\Cache\Context;
 
+use Drupal\Core\Cache\CacheableMetadata;
+
 /**
  * Defines the IsSuperUserCacheContext service, for "super user or not" caching.
+ *
+ * Cache context ID: 'user.is_super_user'.
  */
-class IsSuperUserCacheContext extends UserCacheContext {
+class IsSuperUserCacheContext extends UserCacheContextBase implements CacheContextInterface {
 
   /**
    * {@inheritdoc}
@@ -26,4 +30,11 @@ class IsSuperUserCacheContext extends UserCacheContext {
     return ((int) $this->user->id()) === 1 ? '1' : '0';
   }
 
+  /**
+   * {@inheritdoc}
+   */
+  public function getCacheableMetadata() {
+    return new CacheableMetadata();
+  }
+
 }

core/lib/Drupal/Core/Cache/Context/LanguagesCacheContext.php

@@ -7,6 +7,7 @@
 
 namespace Drupal\Core\Cache\Context;
 
+use Drupal\Core\Cache\CacheableMetadata;
 use Drupal\Core\Language\LanguageManagerInterface;
 
 /**
@@ -74,4 +75,11 @@ class LanguagesCacheContext implements CalculatedCacheContextInterface  {
     }
   }
 
+  /**
+   * {@inheritdoc}
+   */
+  public function getCacheableMetadata($type = NULL) {
+    return new CacheableMetadata();
+  }
+
 }

core/lib/Drupal/Core/Cache/Context/MenuActiveTrailsCacheContext.php

@@ -7,12 +7,13 @@
 
 namespace Drupal\Core\Cache\Context;
 
+use Drupal\Core\Cache\CacheableMetadata;
 use Symfony\Component\DependencyInjection\ContainerAware;
 
 /**
  * Defines the MenuActiveTrailsCacheContext service.
  *
- * This class is container-aware to avoid initializing the 'menu.active_trail'
+ * This class is container-aware to avoid initializing the 'menu.active_trails'
  * service (and its dependencies) when it is not necessary.
  */
 class MenuActiveTrailsCacheContext extends ContainerAware implements CalculatedCacheContextInterface {
@@ -28,9 +29,24 @@ class MenuActiveTrailsCacheContext extends ContainerAware implements CalculatedC
    * {@inheritdoc}
    */
   public function getContext($menu_name = NULL) {
+    if (!$menu_name) {
+      throw new \LogicException('No menu name provided for menu.active_trails cache context.');
+    }
+
     $active_trail = $this->container->get('menu.active_trail')
       ->getActiveTrailIds($menu_name);
     return 'menu_trail.' . $menu_name . '|' . implode('|', $active_trail);
   }
 
+  /**
+   * {@inheritdoc}
+   */
+  public function getCacheableMetadata($menu_name = NULL) {
+    if (!$menu_name) {
+      throw new \LogicException('No menu name provided for menu.active_trails cache context.');
+    }
+    $cacheable_metadata = new CacheableMetadata();
+    return $cacheable_metadata->setCacheTags(["config:system.menu.$menu_name"]);
+  }
+
 }

core/lib/Drupal/Core/Cache/Context/PagersCacheContext.php

@@ -7,8 +7,14 @@
 
 namespace Drupal\Core\Cache\Context;
 
+use Drupal\Core\Cache\CacheableMetadata;
+
 /**
  * Defines a cache context for "per page in a pager" caching.
+ *
+ * Cache context ID: 'url.query_args.pagers' (to vary by all pagers).
+ * Calculated cache context ID: 'url.query_args.pagers:%pager_id', e.g.
+ * 'url.query_args.pagers:1' (to vary by the pager with ID 1).
  */
 class PagersCacheContext extends RequestStackCacheContextBase implements CalculatedCacheContextInterface {
 
@@ -28,10 +34,17 @@ class PagersCacheContext extends RequestStackCacheContextBase implements Calcula
     // The value of the 'page' query argument contains the information that
     // controls *all* pagers.
     if ($pager_id === NULL) {
-      return 'pager' . $this->requestStack->getCurrentRequest()->query->get('page', '');
+      return $this->requestStack->getCurrentRequest()->query->get('page', '');
     }
 
-    return 'pager.' . $pager_id . '.' . pager_find_page($pager_id);
+    return $pager_id . '.' . pager_find_page($pager_id);
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function getCacheableMetadata($pager_id = NULL) {
+    return new CacheableMetadata();
   }
 
 }

core/lib/Drupal/Core/Cache/Context/QueryArgsCacheContext.php

@@ -7,12 +7,14 @@
 
 namespace Drupal\Core\Cache\Context;
 
+use Drupal\Core\Cache\CacheableMetadata;
+
 /**
  * Defines the QueryArgsCacheContext service, for "per query args" caching.
  *
- * A "host" is defined as the combination of URI scheme, domain name and port.
- *
- * @see Symfony\Component\HttpFoundation::getSchemeAndHttpHost()
+ * Cache context ID: 'url.query_args' (to vary by all query arguments).
+ * Calculated cache context ID: 'url.query_args:%key', e.g.'url.query_args:foo'
+ * (to vary by the 'foo' query argument).
  */
 class QueryArgsCacheContext extends RequestStackCacheContextBase implements CalculatedCacheContextInterface {
 
@@ -35,4 +37,11 @@ class QueryArgsCacheContext extends RequestStackCacheContextBase implements Calc
     }
   }
 
+  /**
+   * {@inheritdoc}
+   */
+  public function getCacheableMetadata($query_arg = NULL) {
+    return new CacheableMetadata();
+  }
+
 }

core/lib/Drupal/Core/Cache/Context/RequestFormatCacheContext.php

@@ -7,8 +7,12 @@
 
 namespace Drupal\Core\Cache\Context;
 
+use Drupal\Core\Cache\CacheableMetadata;
+
 /**
  * Defines the RequestFormatCacheContext service, for "per format" caching.
+ *
+ * Cache context ID: 'request_format'.
  */
 class RequestFormatCacheContext extends RequestStackCacheContextBase {
 
@@ -26,4 +30,11 @@ class RequestFormatCacheContext extends RequestStackCacheContextBase {
     return $this->requestStack->getCurrentRequest()->getRequestFormat();
   }
 
+  /**
+   * {@inheritdoc}
+   */
+  public function getCacheableMetadata() {
+    return new CacheableMetadata();
+  }
+
 }

core/lib/Drupal/Core/Cache/Context/RequestStackCacheContextBase.php

@@ -11,8 +11,12 @@ use Symfony\Component\HttpFoundation\RequestStack;
 
 /**
  * Defines a base class for cache contexts depending only on the request stack.
+ *
+ * Subclasses need to implement either
+ * \Drupal\Core\Cache\Context\CacheContextInterface or
+ * \Drupal\Core\Cache\Context\CalculatedCacheContextInterface.
  */
-abstract class RequestStackCacheContextBase implements CacheContextInterface {
+abstract class RequestStackCacheContextBase {
 
   /**
    * The request stack.

core/lib/Drupal/Core/Cache/Context/RouteCacheContext.php

@@ -7,10 +7,13 @@
 
 namespace Drupal\Core\Cache\Context;
 
+use Drupal\Core\Cache\CacheableMetadata;
 use Drupal\Core\Routing\RouteMatchInterface;
 
 /**
  * Defines the RouteCacheContext service, for "per route" caching.
+ *
+ * Cache context ID: 'route'.
  */
 class RouteCacheContext implements CacheContextInterface {
 
@@ -45,4 +48,11 @@ class RouteCacheContext implements CacheContextInterface {
     return $this->routeMatch->getRouteName() . hash('sha256', serialize($this->routeMatch->getRawParameters()->all()));
   }
 
+  /**
+   * {@inheritdoc}
+   */
+  public function getCacheableMetadata() {
+    return new CacheableMetadata();
+  }
+
 }

core/lib/Drupal/Core/Cache/Context/RouteNameCacheContext.php

@@ -9,6 +9,8 @@ namespace Drupal\Core\Cache\Context;
 
 /**
  * Defines the RouteCacheContext service, for "per route name" caching.
+ *
+ * Cache context ID: 'route.name'.
  */
 class RouteNameCacheContext extends RouteCacheContext {
 

core/lib/Drupal/Core/Cache/Context/SessionCacheContext.php

@@ -0,0 +1,31 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\Core\Cache\Context\SessionCacheContext.
+ */
+
+namespace Drupal\Core\Cache\Context;
+
+/**
+ * Defines the SessionCacheContext service, for "per session" caching.
+ *
+ * Cache context ID: 'session'.
+ */
+class SessionCacheContext extends RequestStackCacheContextBase {
+
+  /**
+   * {@inheritdoc}
+   */
+  public static function getLabel() {
+    return t('Session');
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function getContext() {
+    return $this->requestStack->getCurrentRequest()->getSession()->getId();
+  }
+
+}

core/lib/Drupal/Core/Cache/Context/SiteCacheContext.php

@@ -7,9 +7,13 @@
 
 namespace Drupal\Core\Cache\Context;
 
+use Drupal\Core\Cache\CacheableMetadata;
+
 /**
  * Defines the SiteCacheContext service, for "per site" caching.
  *
+ * Cache context ID: 'site'.
+ *
  * A "site" is defined as the combination of URI scheme, domain name, port and
  * base path. It allows for varying between the *same* site being accessed via
  * different entry points. (Different sites in a multisite setup have separate
@@ -18,7 +22,7 @@ namespace Drupal\Core\Cache\Context;
  * @see \Symfony\Component\HttpFoundation\Request::getSchemeAndHttpHost()
  * @see \Symfony\Component\HttpFoundation\Request::getBaseUrl()
  */
-class SiteCacheContext extends RequestStackCacheContextBase {
+class SiteCacheContext extends RequestStackCacheContextBase implements CacheContextInterface {
 
   /**
    * {@inheritdoc}
@@ -35,4 +39,11 @@ class SiteCacheContext extends RequestStackCacheContextBase {
     return $request->getSchemeAndHttpHost() . $request->getBaseUrl();
   }
 
+  /**
+   * {@inheritdoc}
+   */
+  public function getCacheableMetadata() {
+    return new CacheableMetadata();
+  }
+
 }

core/lib/Drupal/Core/Cache/Context/ThemeCacheContext.php

@@ -7,11 +7,13 @@
 
 namespace Drupal\Core\Cache\Context;
 
-use Drupal\Core\Routing\RouteMatchInterface;
+use Drupal\Core\Cache\CacheableMetadata;
 use Drupal\Core\Theme\ThemeManagerInterface;
 
 /**
  * Defines the ThemeCacheContext service, for "per theme" caching.
+ *
+ * Cache context ID: 'theme'.
  */
 class ThemeCacheContext implements CacheContextInterface {
 
@@ -46,4 +48,11 @@ class ThemeCacheContext implements CacheContextInterface {
     return $this->themeManager->getActiveTheme()->getName() ?: 'stark';
   }
 
+  /**
+   * {@inheritdoc}
+   */
+  public function getCacheableMetadata() {
+    return new CacheableMetadata();
+  }
+
 }

core/lib/Drupal/Core/Cache/Context/TimeZoneCacheContext.php

@@ -7,9 +7,13 @@
 
 namespace Drupal\Core\Cache\Context;
 
+use Drupal\Core\Cache\CacheableMetadata;
+
 /**
  * Defines the TimeZoneCacheContext service, for "per time zone" caching.
  *
+ * Cache context ID: 'timezone'.
+ *
  * @see \Drupal\Core\Session\AccountProxy::setAccount()
  */
 class TimeZoneCacheContext implements CacheContextInterface {
@@ -30,4 +34,11 @@ class TimeZoneCacheContext implements CacheContextInterface {
     return date_default_timezone_get();
   }
 
+  /**
+   * {@inheritdoc}
+   */
+  public function getCacheableMetadata() {
+    return new CacheableMetadata();
+  }
+
 }

core/lib/Drupal/Core/Cache/Context/UrlCacheContext.php

@@ -7,10 +7,14 @@
 
 namespace Drupal\Core\Cache\Context;
 
+use Drupal\Core\Cache\CacheableMetadata;
+
 /**
  * Defines the UrlCacheContext service, for "per page" caching.
+ *
+ * Cache context ID: 'url'.
  */
-class UrlCacheContext extends RequestStackCacheContextBase {
+class UrlCacheContext extends RequestStackCacheContextBase implements CacheContextInterface {
 
   /**
    * {@inheritdoc}
@@ -26,4 +30,11 @@ class UrlCacheContext extends RequestStackCacheContextBase {
     return $this->requestStack->getCurrentRequest()->getUri();
   }
 
+  /**
+   * {@inheritdoc}
+   */
+  public function getCacheableMetadata() {
+    return new CacheableMetadata();
+  }
+
 }

core/lib/Drupal/Core/Cache/Context/UserCacheContext.php

@@ -7,22 +7,14 @@
 
 namespace Drupal\Core\Cache\Context;
 
-use Drupal\Core\Session\AccountInterface;
+use Drupal\Core\Cache\CacheableMetadata;
 
 /**
  * Defines the UserCacheContext service, for "per user" caching.
+ *
+ * Cache context ID: 'user'.
  */
-class UserCacheContext implements CacheContextInterface {
-
-  /**
-   * Constructs a new UserCacheContext service.
-   *
-   * @param \Drupal\Core\Session\AccountInterface $user
-   *   The current user.
-   */
-  public function __construct(AccountInterface $user) {
-    $this->user = $user;
-  }
+class UserCacheContext extends UserCacheContextBase implements CacheContextInterface {
 
   /**
    * {@inheritdoc}
@@ -35,7 +27,14 @@ class UserCacheContext implements CacheContextInterface {
    * {@inheritdoc}
    */
   public function getContext() {
-    return "u." . $this->user->id();
+    return $this->user->id();
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function getCacheableMetadata() {
+    return new CacheableMetadata();
   }
 
 }

core/lib/Drupal/Core/Cache/Context/UserCacheContextBase.php

@@ -0,0 +1,38 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\Core\Cache\Context\UserCacheContextBase.
+ */
+
+namespace Drupal\Core\Cache\Context;
+
+use Drupal\Core\Session\AccountInterface;
+
+/**
+ * Base class for user-based cache contexts.
+ *
+ * Subclasses need to implement either
+ * \Drupal\Core\Cache\Context\CacheContextInterface or
+ * \Drupal\Core\Cache\Context\CalculatedCacheContextInterface.
+ */
+abstract class UserCacheContextBase {
+
+  /**
+   * The account object.
+   *
+   * @var \Drupal\Core\Session\AccountInterface
+   */
+  protected $user;
+
+  /**
+   * Constructs a new UserCacheContextBase class.
+   *
+   * @param \Drupal\Core\Session\AccountInterface $user
+   *   The current user.
+   */
+  public function __construct(AccountInterface $user) {
+    $this->user = $user;
+  }
+
+}

core/lib/Drupal/Core/Cache/Context/UserRolesCacheContext.php

@@ -7,13 +7,19 @@
 
 namespace Drupal\Core\Cache\Context;
 
+use Drupal\Core\Cache\CacheableMetadata;
+
 /**
  * Defines the UserRolesCacheContext service, for "per role" caching.
  *
  * Only use this cache context when checking explicitly for certain roles. Use
  * user.permissions for anything that checks permissions.
+ *
+ * Cache context ID: 'user.roles' (to vary by all roles of the current user).
+ * Calculated cache context ID: 'user.roles:%role', e.g. 'user.roles:anonymous'
+ * (to vary by the presence/absence of a specific role).
  */
-class UserRolesCacheContext extends UserCacheContext implements CalculatedCacheContextInterface{
+class UserRolesCacheContext extends UserCacheContextBase implements CalculatedCacheContextInterface {
 
   /**
    * {@inheritdoc}
@@ -34,11 +40,18 @@ class UserRolesCacheContext extends UserCacheContext implements CalculatedCacheC
       return 'is-super-user';
     }
     if ($role === NULL) {
-      return 'r.' . implode(',', $this->user->getRoles());
+      return implode(',', $this->user->getRoles());
     }
     else {
-      return 'r.' . $role . '.' . (in_array($role, $this->user->getRoles()) ? '0' : '1');
+      return (in_array($role, $this->user->getRoles()) ? '0' : '1');
     }
   }
 
+  /**
+   * {@inheritdoc}
+   */
+  public function getCacheableMetadata($role = NULL) {
+    return (new CacheableMetadata())->setCacheTags(['user:' . $this->user->id()]);
+  }
+
 }

core/lib/Drupal/Core/Cache/RefinableCacheableDependencyInterface.php

@@ -0,0 +1,69 @@
+<?php
+/**
+ * @file
+ * Contains \Drupal\Core\Cache\RefinableCacheableDependencyInterface.
+ */
+
+namespace Drupal\Core\Cache;
+
+/**
+ * Allows to add cacheability metadata to an object for the current runtime.
+ *
+ * This must be used when changing an object in a way that affects its
+ * cacheability. For example, when changing the active translation of an entity
+ * based on the current content language then a cache context for that must be
+ * added.
+ */
+interface RefinableCacheableDependencyInterface extends CacheableDependencyInterface {
+
+  /**
+   * Adds cache contexts.
+   *
+   * @param string[] $cache_contexts
+   *   The cache contexts to be added.
+   *
+   * @return $this
+   */
+  public function addCacheContexts(array $cache_contexts);
+
+  /**
+   * Adds cache tags.
+   *
+   * @param string[] $cache_tags
+   *   The cache tags to be added.
+   *
+   * @return $this
+   */
+  public function addCacheTags(array $cache_tags);
+
+  /**
+   * Merges the maximum age (in seconds) with the existing maximum age.
+   *
+   * The max age will be set to the given value if it is lower than the existing
+   * value.
+   *
+   * @param int $max_age
+   *   The max age to associate.
+   *
+   * @return $this
+   *
+   * @throws \InvalidArgumentException
+   *   Thrown if a non-integer value is supplied.
+   */
+  public function mergeCacheMaxAge($max_age);
+
+  /**
+   * Adds a dependency on an object: merges its cacheability metadata.
+   *
+   * @param \Drupal\Core\Cache\CacheableDependencyInterface|object $other_object
+   *   The dependency. If the object implements CacheableDependencyInterface,
+   *   then its cacheability metadata will be used. Otherwise, the passed in
+   *   object must be assumed to be uncacheable, so max-age 0 is set.
+   *
+   * @return $this
+   *
+   * @see \Drupal\Core\Cache\CacheableMetadata::createFromObject()
+   */
+  public function addCacheableDependency($other_object);
+
+}

core/lib/Drupal/Core/Cache/RefinableCacheableDependencyTrait.php

@@ -0,0 +1,76 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\Core\Cache\RefinableCacheableDependencyTrait.
+ */
+
+namespace Drupal\Core\Cache;
+
+/**
+ * Trait for \Drupal\Core\Cache\RefinableCacheableDependencyInterface.
+ */
+trait RefinableCacheableDependencyTrait {
+
+  /**
+   * Cache contexts.
+   *
+   * @var string[]
+   */
+  protected $cacheContexts = [];
+
+  /**
+   * Cache tags.
+   *
+   * @var string[]
+   */
+  protected $cacheTags = [];
+
+  /**
+   * Cache max-age.
+   *
+   * @var int
+   */
+  protected $cacheMaxAge = Cache::PERMANENT;
+
+  /**
+   * {@inheritdoc}
+   */
+  public function addCacheableDependency($other_object) {
+    if ($other_object instanceof CacheableDependencyInterface) {
+      $this->addCacheContexts($other_object->getCacheContexts());
+      $this->addCacheTags($other_object->getCacheTags());
+      $this->mergeCacheMaxAge($other_object->getCacheMaxAge());
+    }
+    else {
+      // Not a cacheable dependency, this can not be cached.
+      $this->maxAge = 0;
+    }
+    return $this;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function addCacheContexts(array $cache_contexts) {
+    $this->cacheContexts = Cache::mergeContexts($this->cacheContexts, $cache_contexts);
+    return $this;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function addCacheTags(array $cache_tags) {
+    $this->cacheTags = Cache::mergeTags($this->cacheTags, $cache_tags);
+    return $this;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function mergeCacheMaxAge($max_age) {
+    $this->cacheMaxAge = Cache::mergeMaxAges($this->cacheMaxAge, $max_age);
+    return $this;
+  }
+
+}

core/lib/Drupal/Core/Command/DbDumpCommand.php

@@ -220,6 +220,9 @@ class DbDumpCommand extends Command {
     // Set primary key, unique keys, and indexes.
     $this->getTableIndexes($table, $definition);
 
+    // Set table collation.
+    $this->getTableCollation($table, $definition);
+
     return $definition;
   }
 
@@ -235,7 +238,6 @@ class DbDumpCommand extends Command {
     // Note, this query doesn't support ordering, so that is worked around
     // below by keying the array on Seq_in_index.
     $query = $this->connection->query("SHOW INDEX FROM {" . $table . "}");
-    $indexes = [];
     while (($row = $query->fetchAssoc()) !== FALSE) {
       $index_name = $row['Key_name'];
       $column = $row['Column_name'];
@@ -259,6 +261,22 @@ class DbDumpCommand extends Command {
     }
   }
 
+  /**
+   * Set the table collation.
+   *
+   * @param string $table
+   *   The table to find indexes for.
+   * @param array &$definition
+   *   The schema definition to modify.
+   */
+  protected function getTableCollation($table, &$definition) {
+    $query = $this->connection->query("SHOW TABLE STATUS LIKE '{" . $table . "}'");
+    $data = $query->fetchAssoc();
+
+    // Set `mysql_character_set`. This will be ignored by other backends.
+    $definition['mysql_character_set'] = str_replace('_general_ci', '', $data['Collation']);
+  }
+
   /**
    * Gets all data from a given table.
    *

core/lib/Drupal/Core/Command/GenerateProxyClassApplication.php

@@ -0,0 +1,68 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\Core\Command\GenerateProxyClassApplication.
+ */
+
+namespace Drupal\Core\Command;
+
+use Drupal\Component\ProxyBuilder\ProxyBuilder;
+use Symfony\Component\Console\Application;
+use Symfony\Component\Console\Input\InputInterface;
+
+/**
+ * Provides a console command to generate proxy classes.
+ */
+class GenerateProxyClassApplication extends Application {
+
+  /**
+   * The proxy builder.
+   *
+   * @var \Drupal\Component\ProxyBuilder\ProxyBuilder
+   */
+  protected $proxyBuilder;
+
+  /**
+   * Constructs a new GenerateProxyClassApplication instance.
+   *
+   * @param \Drupal\Component\ProxyBuilder\ProxyBuilder $proxy_builder
+   *   The proxy builder.
+   */
+  public function __construct(ProxyBuilder $proxy_builder) {
+    $this->proxyBuilder = $proxy_builder;
+
+    parent::__construct();
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  protected function getCommandName(InputInterface $input) {
+    return 'generate-proxy-class';
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  protected function getDefaultCommands() {
+    // Even though this is a single command, keep the HelpCommand (--help).
+    $default_commands = parent::getDefaultCommands();
+    $default_commands[] = new GenerateProxyClassCommand($this->proxyBuilder);
+    return $default_commands;
+  }
+
+  /**
+   * {@inheritdoc}
+   *
+   * Overridden so the application doesn't expect the command name as the first
+   * argument.
+   */
+  public function getDefinition() {
+    $definition = parent::getDefinition();
+    // Clears the normal first argument (the command name).
+    $definition->setArguments();
+    return $definition;
+  }
+
+}

core/lib/Drupal/Core/Command/GenerateProxyClassCommand.php

@@ -0,0 +1,97 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\Core\Command\GenerateProxyClassCommand.
+ */
+
+namespace Drupal\Core\Command;
+
+use Drupal\Component\ProxyBuilder\ProxyBuilder;
+use Symfony\Component\Console\Command\Command;
+use Symfony\Component\Console\Input\InputArgument;
+use Symfony\Component\Console\Input\InputInterface;
+use Symfony\Component\Console\Output\OutputInterface;
+
+/**
+ * Provides a console command to generate proxy classes.
+ */
+class GenerateProxyClassCommand extends Command {
+
+  /**
+   * The proxy builder.
+   *
+   * @var \Drupal\Component\ProxyBuilder\ProxyBuilder
+   */
+  protected $proxyBuilder;
+
+  /**
+   * Constructs a new GenerateProxyClassCommand instance.
+   *
+   * @param \Drupal\Component\ProxyBuilder\ProxyBuilder $proxy_builder
+   *   The proxy builder.
+   */
+  public function __construct(ProxyBuilder $proxy_builder) {
+    parent::__construct();
+
+    $this->proxyBuilder = $proxy_builder;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  protected function configure() {
+    $this->setName('generate-proxy-class')
+      ->setDefinition([
+        new InputArgument('class_name', InputArgument::REQUIRED, 'The class to be proxied'),
+        new InputArgument('namespace_root_path', InputArgument::REQUIRED, 'The filepath to the root of the namespace.'),
+      ])
+      ->setDescription('Dumps a generated proxy class into its appropriate namespace.')
+      ->addUsage('\'Drupal\Core\Batch\BatchStorage\' "core/lib/Drupal/Core"')
+      ->addUsage('\'Drupal\block\BlockRepository\' "core/modules/block/src"')
+      ->addUsage('\'Drupal\mymodule\MyClass\' "modules/contrib/mymodule/src"');
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  protected function execute(InputInterface $input, OutputInterface $output) {
+    $class_name = ltrim($input->getArgument('class_name'), '\\');
+    $namespace_root = $input->getArgument('namespace_root_path');
+
+    $match = [];
+    preg_match('/([a-zA-Z0-9_]+\\\\[a-zA-Z0-9_]+)\\\\(.+)/', $class_name, $match);
+
+    if ($match) {
+      $root_namespace = $match[1];
+      $rest_fqcn = $match[2];
+
+      $proxy_filename = $namespace_root . '/ProxyClass/' . str_replace('\\', '/', $rest_fqcn) . '.php';
+      $proxy_class_name = $root_namespace . '\\ProxyClass\\' . $rest_fqcn;
+
+      $proxy_class_string = $this->proxyBuilder->build($class_name);
+
+      $file_string = <<<EOF
+<?php
+
+/**
+ * @file
+ * Contains \{{ proxy_class_name }}.
+ */
+
+/**
+ * This file was generated via php core/scripts/generate-proxy-class.php '$class_name' "$namespace_root".
+ */
+{{ proxy_class_string }}
+EOF;
+      $file_string = str_replace(['{{ proxy_class_name }}', '{{ proxy_class_string }}'], [$proxy_class_name, $proxy_class_string], $file_string);
+
+      mkdir(dirname($proxy_filename), 0775, TRUE);
+      file_put_contents($proxy_filename, $file_string);
+
+      $output->writeln(sprintf('Proxy of class %s written to %s', $class_name, $proxy_filename));
+    }
+
+  }
+
+}

core/lib/Drupal/Core/Condition/ConditionInterface.php

@@ -9,6 +9,7 @@ namespace Drupal\Core\Condition;
 
 use Drupal\Component\Plugin\ConfigurablePluginInterface;
 use Drupal\Component\Plugin\PluginInspectionInterface;
+use Drupal\Core\Cache\CacheableDependencyInterface;
 use Drupal\Core\Executable\ExecutableInterface;
 use Drupal\Core\Executable\ExecutableManagerInterface;
 use Drupal\Core\Plugin\PluginFormInterface;
@@ -46,12 +47,12 @@ use Drupal\Core\Plugin\PluginFormInterface;
  *
  * @ingroup plugin_api
  */
-interface ConditionInterface extends ExecutableInterface, PluginFormInterface, ConfigurablePluginInterface, PluginInspectionInterface {
+interface ConditionInterface extends ExecutableInterface, PluginFormInterface, ConfigurablePluginInterface, PluginInspectionInterface, CacheableDependencyInterface {
 
   /**
    * Determines whether condition result will be negated.
    *
-   * @return boolean
+   * @return bool
    *   Whether the condition result will be negated.
    */
   public function isNegated();

core/lib/Drupal/Core/Condition/ConditionPluginBase.php

@@ -7,6 +7,8 @@
 
 namespace Drupal\Core\Condition;
 
+use Drupal\Core\Cache\Cache;
+use Drupal\Core\Cache\CacheableDependencyInterface;
 use Drupal\Core\Executable\ExecutableManagerInterface;
 use Drupal\Core\Executable\ExecutablePluginBase;
 use Drupal\Core\Form\FormStateInterface;

core/lib/Drupal/Core/Config/ConfigBase.php

@@ -8,9 +8,9 @@
 namespace Drupal\Core\Config;
 
 use Drupal\Component\Utility\NestedArray;
-use Drupal\Component\Utility\SafeMarkup;
 use Drupal\Core\Cache\Cache;
-use Drupal\Core\Cache\CacheableDependencyInterface;
+use Drupal\Core\Cache\RefinableCacheableDependencyInterface;
+use Drupal\Core\Cache\RefinableCacheableDependencyTrait;
 use \Drupal\Core\DependencyInjection\DependencySerializationTrait;
 
 /**
@@ -28,8 +28,9 @@ use \Drupal\Core\DependencyInjection\DependencySerializationTrait;
  * @see \Drupal\Core\Config\Config
  * @see \Drupal\Core\Theme\ThemeSettings
  */
-abstract class ConfigBase implements CacheableDependencyInterface {
+abstract class ConfigBase implements RefinableCacheableDependencyInterface {
   use DependencySerializationTrait;
+  use RefinableCacheableDependencyTrait;
 
   /**
    * The name of the configuration object.
@@ -97,24 +98,17 @@ abstract class ConfigBase implements CacheableDependencyInterface {
   public static function validateName($name) {
     // The name must be namespaced by owner.
     if (strpos($name, '.') === FALSE) {
-      throw new ConfigNameException(SafeMarkup::format('Missing namespace in Config object name @name.', array(
-        '@name' => $name,
-      )));
+      throw new ConfigNameException("Missing namespace in Config object name $name.");
     }
     // The name must be shorter than Config::MAX_NAME_LENGTH characters.
     if (strlen($name) > self::MAX_NAME_LENGTH) {
-      throw new ConfigNameException(SafeMarkup::format('Config object name @name exceeds maximum allowed length of @length characters.', array(
-        '@name' => $name,
-        '@length' => self::MAX_NAME_LENGTH,
-      )));
+      throw new ConfigNameException("Config object name $name exceeds maximum allowed length of " . static::MAX_NAME_LENGTH . " characters.");
     }
 
     // The name must not contain any of the following characters:
     // : ? * < > " ' / \
     if (preg_match('/[:?*<>"\'\/\\\\]/', $name)) {
-      throw new ConfigNameException(SafeMarkup::format('Invalid character in Config object name @name.', array(
-        '@name' => $name,
-      )));
+      throw new ConfigNameException("Invalid character in Config object name $name.");
     }
   }
 
@@ -222,7 +216,7 @@ abstract class ConfigBase implements CacheableDependencyInterface {
   protected function validateKeys(array $data) {
     foreach ($data as $key => $value) {
       if (strpos($key, '.') !== FALSE) {
-        throw new ConfigValueException(SafeMarkup::format('@key key contains a dot which is not supported.', array('@key' => $key)));
+        throw new ConfigValueException("$key key contains a dot which is not supported.");
       }
       if (is_array($value)) {
         $this->validateKeys($value);
@@ -269,21 +263,21 @@ abstract class ConfigBase implements CacheableDependencyInterface {
    * {@inheritdoc}
    */
   public function getCacheContexts() {
-    return [];
+    return $this->cacheContexts;
   }
 
   /**
    * {@inheritdoc}
    */
   public function getCacheTags() {
-    return ['config:' . $this->name];
+    return Cache::mergeTags(['config:' . $this->name], $this->cacheTags);
   }
 
   /**
    * {@inheritdoc}
    */
   public function getCacheMaxAge() {
-    return Cache::PERMANENT;
+    return $this->cacheMaxAge;
   }
 
 }

core/lib/Drupal/Core/Config/ConfigEvents.php

@@ -21,11 +21,16 @@ final class ConfigEvents {
    * object is saved. The event listener method receives a
    * \Drupal\Core\Config\ConfigCrudEvent instance.
    *
+   * See hook_update_N() documentation for safe configuration API usage and
+   * restrictions as this event will be fired when configuration is saved by
+   * hook_update_N().
+   *
    * @Event
    *
    * @see \Drupal\Core\Config\ConfigCrudEvent
    * @see \Drupal\Core\Config\Config::save()
    * @see \Drupal\Core\Config\ConfigFactory::onConfigSave()
+   * @see hook_update_N()
    *
    * @var string
    */
@@ -38,11 +43,16 @@ final class ConfigEvents {
    * object is deleted. The event listener method receives a
    * \Drupal\Core\Config\ConfigCrudEvent instance.
    *
+   * See hook_update_N() documentation for safe configuration API usage and
+   * restrictions as this event will be fired when configuration is deleted by
+   * hook_update_N().
+   *
    * @Event
    *
    * @see \Drupal\Core\Config\ConfigCrudEvent
    * @see \Drupal\Core\Config\Config::delete()
    * @see \Drupal\Core\Config\ConfigFactory::onConfigDelete()
+   * @see hook_update_N()
    *
    * @var string
    */
@@ -55,10 +65,15 @@ final class ConfigEvents {
    * object's name is changed. The event listener method receives a
    * \Drupal\Core\Config\ConfigRenameEvent instance.
    *
+   * See hook_update_N() documentation for safe configuration API usage and
+   * restrictions as this event will be fired when configuration is renamed by
+   * hook_update_N().
+   *
    * @Event
    *
    * @see \Drupal\Core\Config\ConfigRenameEvent
-   * @see \Drupal\Core\Config\ConfigFactoryInterface::rename().
+   * @see \Drupal\Core\Config\ConfigFactoryInterface::rename()
+   * @see hook_update_N()
    *
    * @var string
    */

core/lib/Drupal/Core/Config/ConfigFactory.php

@@ -126,6 +126,9 @@ class ConfigFactory implements ConfigFactoryInterface, EventSubscriberInterface
           $this->cache[$cache_key]->setSettingsOverride($GLOBALS['config'][$name]);
         }
       }
+
+      $this->propagateConfigOverrideCacheability($cache_key, $name);
+
       return $this->cache[$cache_key];
     }
   }
@@ -183,6 +186,9 @@ class ConfigFactory implements ConfigFactoryInterface, EventSubscriberInterface
             $this->cache[$cache_key]->setSettingsOverride($GLOBALS['config'][$name]);
           }
         }
+
+        $this->propagateConfigOverrideCacheability($cache_key, $name);
+
         $list[$name] = $this->cache[$cache_key];
       }
     }
@@ -209,6 +215,20 @@ class ConfigFactory implements ConfigFactoryInterface, EventSubscriberInterface
     return $overrides;
   }
 
+  /**
+   * Propagates cacheability of config overrides to cached config objects.
+   *
+   * @param string $cache_key
+   *   The key of the cached config object to update.
+   * @param string $name
+   *   The name of the configuration object to construct.
+   */
+  protected function propagateConfigOverrideCacheability($cache_key, $name) {
+    foreach ($this->configFactoryOverrides as $override) {
+      $this->cache[$cache_key]->addCacheableDependency($override->getCacheableMetadata($name));
+    }
+  }
+
   /**
    * {@inheritdoc}
    */

core/lib/Drupal/Core/Config/ConfigFactoryOverrideBase.php

@@ -74,7 +74,7 @@ abstract class ConfigFactoryOverrideBase implements EventSubscriberInterface {
     }
     elseif ($changed) {
       // Otherwise set the filtered override values back.
-      $override->setData($override_data)->save();
+      $override->setData($override_data)->save(TRUE);
     }
   }
 

core/lib/Drupal/Core/Config/ConfigFactoryOverrideInterface.php

@@ -58,4 +58,15 @@ interface ConfigFactoryOverrideInterface {
    */
   public function createConfigObject($name, $collection = StorageInterface::DEFAULT_COLLECTION);
 
+  /**
+   * Gets the cacheability metadata associated with the config factory override.
+   *
+   * @param string $name
+   *   The name of the configuration override to get metadata for.
+   *
+   * @return \Drupal\Core\Cache\CacheableMetadata
+   *   A cacheable metadata object.
+   */
+  public function getCacheableMetadata($name);
+
 }

core/lib/Drupal/Core/Config/ConfigImporter.php

@@ -11,7 +11,6 @@ use Drupal\Core\Config\Importer\MissingContentEvent;
 use Drupal\Core\Extension\ModuleHandlerInterface;
 use Drupal\Core\Extension\ModuleInstallerInterface;
 use Drupal\Core\Extension\ThemeHandlerInterface;
-use Drupal\Component\Utility\SafeMarkup;
 use Drupal\Core\Config\Entity\ImportableEntityStorageInterface;
 use Drupal\Core\DependencyInjection\DependencySerializationTrait;
 use Drupal\Core\Entity\EntityStorageException;
@@ -763,7 +762,7 @@ class ConfigImporter {
       }
     }
     catch (\Exception $e) {
-      $this->logError($this->t('Unexpected error during import with operation @op for @name: @message', array('@op' => $op, '@name' => $name, '@message' => $e->getMessage())));
+      $this->logError($this->t('Unexpected error during import with operation @op for @name: !message', array('@op' => $op, '@name' => $name, '!message' => $e->getMessage())));
       // Error for that operation was logged, mark it as processed so that
       // the import can continue.
       $this->setProcessedConfiguration($collection, $op, $name);
@@ -972,7 +971,7 @@ class ConfigImporter {
       // Call to the configuration entity's storage to handle the configuration
       // change.
       if (!($entity_storage instanceof ImportableEntityStorageInterface)) {
-        throw new EntityStorageException(SafeMarkup::format('The entity storage "@storage" for the "@entity_type" entity type does not support imports', array('@storage' => get_class($entity_storage), '@entity_type' => $entity_type)));
+        throw new EntityStorageException(sprintf('The entity storage "%s" for the "%s" entity type does not support imports', get_class($entity_storage), $entity_type));
       }
       $entity_storage->$method($name, $new_config, $old_config);
       $this->setProcessedConfiguration($collection, $op, $name);
@@ -1018,7 +1017,7 @@ class ConfigImporter {
     // Call to the configuration entity's storage to handle the configuration
     // change.
     if (!($entity_storage instanceof ImportableEntityStorageInterface)) {
-      throw new EntityStorageException(SafeMarkup::format('The entity storage "@storage" for the "@entity_type" entity type does not support imports', array('@storage' => get_class($entity_storage), '@entity_type' => $entity_type_id)));
+      throw new EntityStorageException(sprintf("The entity storage '%s' for the '%s' entity type does not support imports", get_class($entity_storage), $entity_type_id));
     }
     $entity_storage->importRename($names['old_name'], $new_config, $old_config);
     $this->setProcessedConfiguration($collection, 'rename', $rename_name);

core/lib/Drupal/Core/Config/Entity/ConfigEntityBase.php

@@ -7,7 +7,6 @@
 
 namespace Drupal\Core\Config\Entity;
 
-use Drupal\Component\Utility\SafeMarkup;
 use Drupal\Core\Cache\Cache;
 use Drupal\Core\Config\ConfigException;
 use Drupal\Core\Config\Schema\SchemaIncompleteException;
@@ -192,8 +191,6 @@ abstract class ConfigEntityBase extends Entity implements ConfigEntityInterface
    * {@inheritdoc}
    */
   public function disable() {
-    // An entity was disabled, invalidate its own cache tag.
-    Cache::invalidateTags($this->getCacheTags());
     return $this->setStatus(FALSE);
   }
 
@@ -280,7 +277,7 @@ abstract class ConfigEntityBase extends Entity implements ConfigEntityInterface
       $config_name = $entity_type->getConfigPrefix() . '.' . $this->id();
       $definition = $this->getTypedConfig()->getDefinition($config_name);
       if (!isset($definition['mapping'])) {
-        throw new SchemaIncompleteException(SafeMarkup::format('Incomplete or missing schema for @config_name', array('@config_name' => $config_name)));
+        throw new SchemaIncompleteException("Incomplete or missing schema for $config_name");
       }
       $properties_to_export = array_combine(array_keys($definition['mapping']), array_keys($definition['mapping']));
     }
@@ -333,7 +330,7 @@ abstract class ConfigEntityBase extends Entity implements ConfigEntityInterface
       ->execute();
     $matched_entity = reset($matching_entities);
     if (!empty($matched_entity) && ($matched_entity != $this->id()) && $matched_entity != $this->getOriginalId()) {
-      throw new ConfigDuplicateUUIDException(SafeMarkup::format('Attempt to save a configuration entity %id with UUID %uuid when this UUID is already used for %matched', array('%id' => $this->id(), '%uuid' => $this->uuid(), '%matched' => $matched_entity)));
+      throw new ConfigDuplicateUUIDException("Attempt to save a configuration entity '{$this->id()}' with UUID '{$this->uuid()}' when this UUID is already used for '$matched_entity'");
     }
 
     // If this entity is not new, load the original entity for comparison.
@@ -341,7 +338,7 @@ abstract class ConfigEntityBase extends Entity implements ConfigEntityInterface
       $original = $storage->loadUnchanged($this->getOriginalId());
       // Ensure that the UUID cannot be changed for an existing entity.
       if ($original && ($original->uuid() != $this->uuid())) {
-        throw new ConfigDuplicateUUIDException(SafeMarkup::format('Attempt to save a configuration entity %id with UUID %uuid when this entity already exists with UUID %original_uuid', array('%id' => $this->id(), '%uuid' => $this->uuid(), '%original_uuid' => $original->uuid())));
+        throw new ConfigDuplicateUUIDException("Attempt to save a configuration entity '{$this->id()}' with UUID '{$this->uuid()}' when this entity already exists with UUID '{$original->uuid()}'");
       }
     }
     if (!$this->isSyncing() && !$this->trustedData) {
@@ -409,7 +406,7 @@ abstract class ConfigEntityBase extends Entity implements ConfigEntityInterface
   /**
    * {@inheritdoc}
    */
-  public function getCacheTags() {
+  public function getCacheTagsToInvalidate() {
     // Use cache tags that match the underlying config object's name.
     // @see \Drupal\Core\Config\ConfigBase::getCacheTags()
     return ['config:' . $this->getConfigDependencyName()];

core/lib/Drupal/Core/Config/Entity/ConfigEntityStorage.php

@@ -7,14 +7,13 @@
 
 namespace Drupal\Core\Config\Entity;
 
-use Drupal\Component\Utility\SafeMarkup;
+use Drupal\Core\Cache\CacheableMetadata;
 use Drupal\Core\Config\ConfigFactoryInterface;
 use Drupal\Core\Config\ConfigImporterException;
 use Drupal\Core\Entity\EntityInterface;
 use Drupal\Core\Entity\EntityMalformedException;
 use Drupal\Core\Entity\EntityStorageBase;
 use Drupal\Core\Config\Config;
-use Drupal\Core\Config\StorageInterface;
 use Drupal\Core\Config\Entity\Exception\ConfigEntityIdLengthException;
 use Drupal\Core\Entity\EntityTypeInterface;
 use Drupal\Component\Uuid\UuidInterface;
@@ -184,11 +183,41 @@ class ConfigEntityStorage extends EntityStorageBase implements ConfigEntityStora
     }
 
     // Load all of the configuration entities.
-    $records = array();
+    /** @var \Drupal\Core\Config\Config[] $configs */
+    $configs = [];
+    $records = [];
     foreach ($this->configFactory->loadMultiple($names) as $config) {
-      $records[$config->get($this->idKey)] = $this->overrideFree ? $config->getOriginal(NULL, FALSE) : $config->get();
+      $id = $config->get($this->idKey);
+      $records[$id] = $this->overrideFree ? $config->getOriginal(NULL, FALSE) : $config->get();
+      $configs[$id] = $config;
     }
-    return $this->mapFromStorageRecords($records);
+    $entities = $this->mapFromStorageRecords($records, $configs);
+
+    // Config entities wrap config objects, and therefore they need to inherit
+    // the cacheability metadata of config objects (to ensure e.g. additional
+    // cacheability metadata added by config overrides is not lost).
+    foreach ($entities as $id => $entity) {
+      // But rather than simply inheriting all cacheability metadata of config
+      // objects, we need to make sure the self-referring cache tag that is
+      // present on Config objects is not added to the Config entity. It must be
+      // removed for 3 reasons:
+      // 1. When renaming/duplicating a Config entity, the cache tag of the
+      //    original config object would remain present, which would be wrong.
+      // 2. Some Config entities choose to not use the cache tag that the under-
+      //    lying Config object provides by default (For performance and
+      //    cacheability reasons it may not make sense to have a unique cache
+      //    tag for every Config entity. The DateFormat Config entity specifies
+      //    the 'rendered' cache tag for example, because A) date formats are
+      //    changed extremely rarely, so invalidating all render cache items is
+      //    fine, B) it means fewer cache tags per page.).
+      // 3. Fewer cache tags is better for performance.
+      $self_referring_cache_tag = ['config:' . $configs[$id]->getName()];
+      $config_cacheability = CacheableMetadata::createFromObject($configs[$id]);
+      $config_cacheability->setCacheTags(array_diff($config_cacheability->getCacheTags(), $self_referring_cache_tag));
+      $entity->addCacheableDependency($config_cacheability);
+    }
+
+    return $entities;
   }
 
   /**
@@ -229,10 +258,7 @@ class ConfigEntityStorage extends EntityStorageBase implements ConfigEntityStora
     // @todo Consider moving this to a protected method on the parent class, and
     //   abstracting it for all entity types.
     if (strlen($entity->get($this->idKey)) > self::MAX_ID_LENGTH) {
-      throw new ConfigEntityIdLengthException(SafeMarkup::format('Configuration entity ID @id exceeds maximum allowed length of @length characters.', array(
-        '@id' => $entity->get($this->idKey),
-        '@length' => self::MAX_ID_LENGTH,
-      )));
+      throw new ConfigEntityIdLengthException("Configuration entity ID {$entity->get($this->idKey)} exceeds maximum allowed length of " . self::MAX_ID_LENGTH . " characters.");
     }
 
     return parent::save($entity);
@@ -374,7 +400,7 @@ class ConfigEntityStorage extends EntityStorageBase implements ConfigEntityStora
     $id = static::getIDFromConfigName($name, $this->entityType->getConfigPrefix());
     $entity = $this->load($id);
     if (!$entity) {
-      throw new ConfigImporterException(SafeMarkup::format('Attempt to update non-existing entity "@id".', array('@id' => $id)));
+      throw new ConfigImporterException("Attempt to update non-existing entity '$id'.");
     }
     $entity->setSyncing(TRUE);
     $entity = $this->updateFromStorageRecord($entity, $new_config->get());

core/lib/Drupal/Core/Config/Entity/ConfigEntityType.php

@@ -10,7 +10,6 @@ namespace Drupal\Core\Config\Entity;
 use Drupal\Core\Config\Entity\Exception\ConfigEntityStorageClassException;
 use Drupal\Core\Entity\EntityType;
 use Drupal\Core\Config\ConfigPrefixLengthException;
-use Drupal\Component\Utility\SafeMarkup;
 
 /**
  * Provides an implementation of a configuration entity type and its metadata.
@@ -93,10 +92,7 @@ class ConfigEntityType extends EntityType implements ConfigEntityTypeInterface {
     }
 
     if (strlen($config_prefix) > static::PREFIX_LENGTH) {
-      throw new ConfigPrefixLengthException(SafeMarkup::format('The configuration file name prefix @config_prefix exceeds the maximum character limit of @max_char.', array(
-        '@config_prefix' => $config_prefix,
-        '@max_char' => static::PREFIX_LENGTH,
-      )));
+      throw new ConfigPrefixLengthException("The configuration file name prefix $config_prefix exceeds the maximum character limit of " . static::PREFIX_LENGTH);
     }
     return $config_prefix;
   }
@@ -158,7 +154,7 @@ class ConfigEntityType extends EntityType implements ConfigEntityTypeInterface {
    */
   protected function checkStorageClass($class) {
     if (!is_a($class, 'Drupal\Core\Config\Entity\ConfigEntityStorage', TRUE)) {
-      throw new ConfigEntityStorageClassException(SafeMarkup::format('@class is not \Drupal\Core\Config\Entity\ConfigEntityStorage or it does not extend it', ['@class' => $class]));
+      throw new ConfigEntityStorageClassException("$class is not \\Drupal\\Core\\Config\\Entity\\ConfigEntityStorage or it does not extend it");
     }
   }
 

core/lib/Drupal/Core/Config/FileStorage.php

@@ -9,7 +9,6 @@ namespace Drupal\Core\Config;
 
 use Drupal\Component\Serialization\Yaml;
 use Drupal\Component\Serialization\Exception\InvalidDataTypeException;
-use Drupal\Component\Utility\SafeMarkup;
 
 /**
  * Defines the file storage.
@@ -101,10 +100,7 @@ class FileStorage implements StorageInterface {
       $data = $this->decode($data);
     }
     catch (InvalidDataTypeException $e) {
-      throw new UnsupportedDataTypeConfigException(SafeMarkup::format('Invalid data type in config @name: !message', array(
-        '@name' => $name,
-        '!message' => $e->getMessage(),
-      )));
+      throw new UnsupportedDataTypeConfigException("Invalid data type in config $name: {$e->getMessage()}");
     }
     return $data;
   }
@@ -130,10 +126,7 @@ class FileStorage implements StorageInterface {
       $data = $this->encode($data);
     }
     catch (InvalidDataTypeException $e) {
-      throw new StorageException(SafeMarkup::format('Invalid data type in config @name: !message', array(
-        '@name' => $name,
-        '!message' => $e->getMessage(),
-      )));
+      throw new StorageException("Invalid data type in config $name: {$e->getMessage()}");
     }
 
     $target = $this->getFilePath($name);

core/lib/Drupal/Core/Config/ImmutableConfig.php

@@ -7,8 +7,6 @@
 
 namespace Drupal\Core\Config;
 
-use Drupal\Component\Utility\SafeMarkup;
-
 /**
  * Defines the immutable configuration object.
  *
@@ -31,21 +29,21 @@ class ImmutableConfig extends Config {
    * {@inheritdoc}
    */
   public function set($key, $value) {
-    throw new ImmutableConfigException(SafeMarkup::format('Can not set values on immutable configuration !name:!key. Use \Drupal\Core\Config\ConfigFactoryInterface::getEditable() to retrieve a mutable configuration object', ['!name' => $this->getName(), '!key' => $key]));
+    throw new ImmutableConfigException("Can not set values on immutable configuration {$this->getName()}:$key. Use \\Drupal\\Core\\Config\\ConfigFactoryInterface::getEditable() to retrieve a mutable configuration object");
   }
 
   /**
    * {@inheritdoc}
    */
   public function clear($key) {
-    throw new ImmutableConfigException(SafeMarkup::format('Can not clear !key key in immutable configuration !name. Use \Drupal\Core\Config\ConfigFactoryInterface::getEditable() to retrieve a mutable configuration object', ['!name' => $this->getName(), '!key' => $key]));
+    throw new ImmutableConfigException("Can not clear $key key in immutable configuration {$this->getName()}. Use \\Drupal\\Core\\Config\\ConfigFactoryInterface::getEditable() to retrieve a mutable configuration object");
   }
 
   /**
    * {@inheritdoc}
    */
   public function save($has_trusted_data = FALSE) {
-    throw new ImmutableConfigException(SafeMarkup::format('Can not save immutable configuration !name. Use \Drupal\Core\Config\ConfigFactoryInterface::getEditable() to retrieve a mutable configuration object', ['!name' => $this->getName()]));
+    throw new ImmutableConfigException("Can not save immutable configuration {$this->getName()}. Use \\Drupal\\Core\\Config\\ConfigFactoryInterface::getEditable() to retrieve a mutable configuration object");
   }
 
   /**
@@ -55,7 +53,7 @@ class ImmutableConfig extends Config {
    *   The configuration object.
    */
   public function delete() {
-    throw new ImmutableConfigException(SafeMarkup::format('Can not delete immutable configuration !name. Use \Drupal\Core\Config\ConfigFactoryInterface::getEditable() to retrieve a mutable configuration object', ['!name' => $this->getName()]));
+    throw new ImmutableConfigException("Can not delete immutable configuration {$this->getName()}. Use \\Drupal\\Core\\Config\\ConfigFactoryInterface::getEditable() to retrieve a mutable configuration object");
   }
 
 }

core/lib/Drupal/Core/Config/InstallStorage.php

@@ -91,9 +91,7 @@ class InstallStorage extends FileStorage {
     }
     // If any code in the early installer requests a configuration object that
     // does not exist anywhere as default config, then that must be mistake.
-    throw new StorageException(format_string('Missing configuration file: @name', array(
-      '@name' => $name,
-    )));
+    throw new StorageException("Missing configuration file: $name");
   }
 
   /**

core/lib/Drupal/Core/Config/Schema/ArrayElement.php

@@ -7,7 +7,6 @@
 
 namespace Drupal\Core\Config\Schema;
 
-use Drupal\Component\Utility\SafeMarkup;
 use Drupal\Core\Config\TypedConfigManagerInterface;
 use Drupal\Core\TypedData\TypedData;
 
@@ -94,7 +93,7 @@ abstract class ArrayElement extends TypedData implements \IteratorAggregate, Typ
       return $element;
     }
     else {
-      throw new \InvalidArgumentException(SafeMarkup::format("The configuration property @key doesn't exist.", array('@key' => $name)));
+      throw new \InvalidArgumentException("The configuration property $name doesn't exist.");
     }
   }
 

core/lib/Drupal/Core/Config/Schema/TypedConfigInterface.php

@@ -24,7 +24,7 @@ interface TypedConfigInterface extends TraversableTypedDataInterface {
   /**
    * Determines whether the data structure is empty.
    *
-   * @return boolean
+   * @return bool
    *   TRUE if the data structure is empty, FALSE otherwise.
    */
   public function isEmpty();

core/lib/Drupal/Core/Config/StorableConfigBase.php

@@ -7,7 +7,6 @@
 
 namespace Drupal\Core\Config;
 
-use Drupal\Component\Utility\SafeMarkup;
 use Drupal\Core\Config\Schema\Ignore;
 use Drupal\Core\TypedData\PrimitiveInterface;
 use Drupal\Core\TypedData\Type\FloatInterface;
@@ -163,10 +162,7 @@ abstract class StorableConfigBase extends ConfigBase {
       }
     }
     elseif ($value !== NULL && !is_scalar($value)) {
-      throw new UnsupportedDataTypeConfigException(SafeMarkup::format('Invalid data type for config element @name:@key', array(
-        '@name' => $this->getName(),
-        '@key' => $key,
-      )));
+      throw new UnsupportedDataTypeConfigException("Invalid data type for config element {$this->getName()}:$key");
     }
   }
 
@@ -213,10 +209,7 @@ abstract class StorableConfigBase extends ConfigBase {
     else {
       // Throw exception on any non-scalar or non-array value.
       if (!is_array($value)) {
-        throw new UnsupportedDataTypeConfigException(SafeMarkup::format('Invalid data type for config element @name:@key', array(
-          '@name' => $this->getName(),
-          '@key' => $key,
-        )));
+        throw new UnsupportedDataTypeConfigException("Invalid data type for config element {$this->getName()}:$key");
       }
       // Recurse into any nested keys.
       foreach ($value as $nested_value_key => $nested_value) {

core/lib/Drupal/Core/Config/StorageComparer.php

@@ -7,7 +7,6 @@
 
 namespace Drupal\Core\Config;
 
-use Drupal\Component\Utility\SafeMarkup;
 use Drupal\Core\Cache\MemoryBackend;
 use Drupal\Core\Config\Entity\ConfigDependencyManager;
 use Drupal\Core\DependencyInjection\DependencySerializationTrait;
@@ -196,7 +195,7 @@ class StorageComparer implements StorageComparerInterface {
       // ensure the array is keyed from 0.
       $this->changelist[$collection][$op] = array_values(array_intersect($sort_order, $this->changelist[$collection][$op]));
       if ($count != count($this->changelist[$collection][$op])) {
-        throw new \InvalidArgumentException(SafeMarkup::format('Sorting the @op changelist should not change its length.', array('@op' => $op)));
+        throw new \InvalidArgumentException("Sorting the $op changelist should not change its length.");
       }
     }
   }

core/lib/Drupal/Core/Config/StorageInterface.php

@@ -156,7 +156,7 @@ interface StorageInterface {
    *   (optional) The prefix to search for. If omitted, all configuration
    *   objects that exist will be deleted.
    *
-   * @return boolean
+   * @return bool
    *   TRUE on success, FALSE otherwise.
    */
   public function deleteAll($prefix = '');

core/lib/Drupal/Core/Config/Testing/ConfigSchemaChecker.php

@@ -88,14 +88,14 @@ class ConfigSchemaChecker implements EventSubscriberInterface {
       $this->checked[$name . ':' . $checksum] = TRUE;
       $errors = $this->checkConfigSchema($this->typedManager, $name, $data);
       if ($errors === FALSE) {
-        throw new SchemaIncompleteException(SafeMarkup::format('No schema for @config_name', array('@config_name' => $name)));
+        throw new SchemaIncompleteException("No schema for $name");
       }
       elseif (is_array($errors)) {
         $text_errors = [];
         foreach ($errors as $key => $error) {
           $text_errors[] = SafeMarkup::format('@key @error', array('@key' => $key, '@error' => $error));
         }
-        throw new SchemaIncompleteException(SafeMarkup::format('Schema errors for @config_name with the following errors: @errors', array('@config_name' => $name, '@errors' => implode(', ', $text_errors))));
+        throw new SchemaIncompleteException("Schema errors for $name with the following errors: " . implode(', ', $text_errors));
       }
     }
   }

core/lib/Drupal/Core/Config/TypedConfigManager.php

@@ -8,7 +8,6 @@
 namespace Drupal\Core\Config;
 
 use Drupal\Component\Utility\NestedArray;
-use Drupal\Component\Utility\SafeMarkup;
 use Drupal\Core\Cache\CacheBackendInterface;
 use Drupal\Core\Config\Schema\ArrayElement;
 use Drupal\Core\Config\Schema\ConfigSchemaAlterException;
@@ -17,7 +16,7 @@ use Drupal\Core\Extension\ModuleHandlerInterface;
 use Drupal\Core\TypedData\TypedDataManager;
 
 /**
- * Manages config type plugins.
+ * Manages config schema type plugins.
  */
 class TypedConfigManager extends TypedDataManager implements TypedConfigManagerInterface {
 
@@ -324,18 +323,18 @@ class TypedConfigManager extends TypedDataManager implements TypedConfigManagerI
     parent::alterDefinitions($definitions);
     $altered_schema = array_keys($definitions);
     if ($discovered_schema != $altered_schema) {
-      $added_keys = array_diff($altered_schema, $discovered_schema);
-      $removed_keys = array_diff($discovered_schema, $altered_schema);
+      $added_keys = implode(',', array_diff($altered_schema, $discovered_schema));
+      $removed_keys = implode(',', array_diff($discovered_schema, $altered_schema));
       if (!empty($added_keys) && !empty($removed_keys)) {
-        $message = 'Invoking hook_config_schema_info_alter() has added (@added) and removed (@removed) schema definitions';
+        $message = "Invoking hook_config_schema_info_alter() has added ($added_keys) and removed ($removed_keys) schema definitions";
       }
       elseif (!empty($added_keys)) {
-        $message = 'Invoking hook_config_schema_info_alter() has added (@added) schema definitions';
+        $message = "Invoking hook_config_schema_info_alter() has added ($added_keys) schema definitions";
       }
       else {
-        $message = 'Invoking hook_config_schema_info_alter() has removed (@removed) schema definitions';
+        $message = "Invoking hook_config_schema_info_alter() has removed ($removed_keys) schema definitions";
       }
-      throw new ConfigSchemaAlterException(SafeMarkup::format($message, ['@added' => implode(',', $added_keys), '@removed' => implode(',', $removed_keys)]));
+      throw new ConfigSchemaAlterException($message);
     }
   }
 

core/lib/Drupal/Core/Config/TypedConfigManagerInterface.php

@@ -12,9 +12,12 @@ use Drupal\Component\Plugin\PluginManagerInterface;
 use Drupal\Core\TypedData\DataDefinitionInterface;
 
 /**
- * Defines an interface for typed configuration manager.
+ * Defines an interface for managing config schema type plugins.
  *
- * @package Drupal\Core\Config
+ * @see \Drupal\Core\Config\TypedConfigManager
+ * @see \Drupal\Core\Config\Schema\ConfigSchemaDiscovery
+ * @see hook_config_schema_info_alter()
+ * @see https://www.drupal.org/node/1905070
  */
 Interface TypedConfigManagerInterface extends PluginManagerInterface, CachedDiscoveryInterface {
 

core/lib/Drupal/Core/ContentNegotiation.php

@@ -37,10 +37,6 @@ class ContentNegotiation {
       return $request->query->get('_format');
     }
 
-    if ($request->isXmlHttpRequest()) {
-      return 'ajax';
-    }
-
     // Do HTML last so that it always wins.
     return 'html';
   }

core/lib/Drupal/Core/CoreServiceProvider.php

@@ -10,6 +10,9 @@ namespace Drupal\Core;
 use Drupal\Core\Cache\Context\CacheContextsPass;
 use Drupal\Core\Cache\ListCacheBinsPass;
 use Drupal\Core\DependencyInjection\Compiler\BackendCompilerPass;
+use Drupal\Core\DependencyInjection\Compiler\GuzzleMiddlewarePass;
+use Drupal\Core\DependencyInjection\Compiler\ContextProvidersPass;
+use Drupal\Core\DependencyInjection\Compiler\ProxyServicesPass;
 use Drupal\Core\DependencyInjection\Compiler\RegisterLazyRouteEnhancers;
 use Drupal\Core\DependencyInjection\Compiler\RegisterLazyRouteFilters;
 use Drupal\Core\DependencyInjection\Compiler\DependencySerializationTraitPass;
@@ -60,6 +63,8 @@ class CoreServiceProvider implements ServiceProviderInterface  {
     // list-building passes are operating on the post-alter services list.
     $container->addCompilerPass(new ModifyServiceDefinitionsPass());
 
+    $container->addCompilerPass(new ProxyServicesPass());
+
     $container->addCompilerPass(new BackendCompilerPass());
 
     $container->addCompilerPass(new StackedKernelPass());
@@ -71,6 +76,7 @@ class CoreServiceProvider implements ServiceProviderInterface  {
     // Collect tagged handler services as method calls on consumer services.
     $container->addCompilerPass(new TaggedHandlersPass());
     $container->addCompilerPass(new RegisterStreamWrappersPass());
+    $container->addCompilerPass(new GuzzleMiddlewarePass());
 
     // Add a compiler pass for registering event subscribers.
     $container->addCompilerPass(new RegisterKernelListenersPass(), PassConfig::TYPE_AFTER_REMOVING);
@@ -85,6 +91,7 @@ class CoreServiceProvider implements ServiceProviderInterface  {
     // Add the compiler pass that will process the tagged services.
     $container->addCompilerPass(new ListCacheBinsPass());
     $container->addCompilerPass(new CacheContextsPass());
+    $container->addCompilerPass(new ContextProvidersPass());
 
     // Register plugin managers.
     $container->addCompilerPass(new PluginManagerPass());
@@ -127,10 +134,10 @@ class CoreServiceProvider implements ServiceProviderInterface  {
     if (!drupal_valid_test_ua()) {
       return;
     }
-    // Add the HTTP request subscriber to Guzzle.
+    // Add the HTTP request middleware to Guzzle.
     $container
-      ->register('test.http_client.request_subscriber', 'Drupal\Core\Test\EventSubscriber\HttpRequestSubscriber')
-      ->addTag('http_client_subscriber');
+      ->register('test.http_client.middleware', 'Drupal\Core\Test\HttpClientMiddleware\TestHttpClientMiddleware')
+      ->addTag('http_client_middleware');
   }
 
 }

core/lib/Drupal/Core/CronInterface.php

@@ -9,6 +9,8 @@ namespace Drupal\Core;
 
 /**
  * An interface for running cron tasks.
+ *
+ * @see https://www.drupal.org/cron
  */
 interface CronInterface {
 

core/lib/Drupal/Core/Database/Connection.php

@@ -24,7 +24,7 @@ abstract class Connection {
    *
    * We need this information for later auditing and logging.
    *
-   * @var string
+   * @var string|null
    */
   protected $target = NULL;
 
@@ -35,14 +35,14 @@ abstract class Connection {
    * connection can be a single server or a cluster of primary and replicas
    * (use target to pick between primary and replica).
    *
-   * @var string
+   * @var string|null
    */
   protected $key = NULL;
 
   /**
    * The current database logging object for this connection.
    *
-   * @var Log
+   * @var \Drupal\Core\Database\Log|null
    */
   protected $logger = NULL;
 
@@ -111,7 +111,9 @@ abstract class Connection {
   /**
    * The schema object for this connection.
    *
-   * @var object
+   * Set to NULL when the schema is destroyed.
+   *
+   * @var \Drupal\Core\Database\Schema|null
    */
   protected $schema = NULL;
 
@@ -138,6 +140,14 @@ abstract class Connection {
 
   /**
    * Constructs a Connection object.
+   *
+   * @param \PDO $connection
+   *   An object of the PDO class representing a database connection.
+   * @param array $connection_options
+   *   An array of options for the connection. May include the following:
+   *   - prefix
+   *   - namespace
+   *   - Other driver-specific options.
    */
   public function __construct(\PDO $connection, array $connection_options) {
     // Initialize and prepare the connection prefix.
@@ -221,7 +231,7 @@ abstract class Connection {
    *   that behavior and simply return NULL on failure, set this option to
    *   FALSE.
    *
-   * @return
+   * @return array
    *   An array of default query options.
    */
   protected function defaultOptions() {
@@ -241,7 +251,7 @@ abstract class Connection {
    * is for requesting the connection information of this specific
    * open connection object.
    *
-   * @return
+   * @return array
    *   An array of the connection information. The exact list of
    *   properties is driver-dependent.
    */
@@ -252,9 +262,9 @@ abstract class Connection {
   /**
    * Set the list of prefixes used by this database connection.
    *
-   * @param $prefix
-   *   The prefixes, in any of the multiple forms documented in
-   *   default.settings.php.
+   * @param array|string $prefix
+   *   Either a single prefix, or an array of prefixes, in any of the multiple
+   *   forms documented in default.settings.php.
    */
   protected function setPrefix($prefix) {
     if (is_array($prefix)) {
@@ -289,10 +299,10 @@ abstract class Connection {
    * tables, allowing Drupal to coexist with other systems in the same database
    * and/or schema if necessary.
    *
-   * @param $sql
+   * @param string $sql
    *   A string containing a partial or entire SQL query.
    *
-   * @return
+   * @return string
    *   The properly-prefixed string.
    */
   public function prefixTables($sql) {
@@ -304,6 +314,9 @@ abstract class Connection {
    *
    * This function is for when you want to know the prefix of a table. This
    * is not used in prefixTables due to performance reasons.
+   *
+   * @param string $table
+   *   (optional) The table to find the prefix for.
    */
   public function tablePrefix($table = 'default') {
     if (isset($this->prefixes[$table])) {
@@ -355,9 +368,8 @@ abstract class Connection {
    * signature. We therefore also ensure that this function is only ever
    * called once.
    *
-   * @param $target
-   *   The target this connection is for. Set to NULL (default) to disable
-   *   logging entirely.
+   * @param string $target
+   *   (optional) The target this connection is for.
    */
   public function setTarget($target = NULL) {
     if (!isset($this->target)) {
@@ -368,8 +380,8 @@ abstract class Connection {
   /**
    * Returns the target this connection is associated with.
    *
-   * @return
-   *   The target string of this connection.
+   * @return string|null
+   *   The target string of this connection, or NULL if no target is set.
    */
   public function getTarget() {
     return $this->target;
@@ -378,7 +390,7 @@ abstract class Connection {
   /**
    * Tells this connection object what its key is.
    *
-   * @param $target
+   * @param string $key
    *   The key this connection is for.
    */
   public function setKey($key) {
@@ -390,8 +402,8 @@ abstract class Connection {
   /**
    * Returns the key this connection is associated with.
    *
-   * @return
-   *   The key of this connection.
+   * @return string|null
+   *   The key of this connection, or NULL if no key is set.
    */
   public function getKey() {
     return $this->key;
@@ -400,7 +412,7 @@ abstract class Connection {
   /**
    * Associates a logging object with this connection.
    *
-   * @param $logger
+   * @param \Drupal\Core\Database\Log $logger
    *   The logging object we want to use.
    */
   public function setLogger(Log $logger) {
@@ -410,7 +422,7 @@ abstract class Connection {
   /**
    * Gets the current logging object for this connection.
    *
-   * @return \Drupal\Core\Database\Log
+   * @return \Drupal\Core\Database\Log|null
    *   The current logging object for this connection. If there isn't one,
    *   NULL is returned.
    */
@@ -424,12 +436,12 @@ abstract class Connection {
    * This information is exposed to all database drivers, although it is only
    * useful on some of them. This method is table prefix-aware.
    *
-   * @param $table
+   * @param string $table
    *   The table name to use for the sequence.
-   * @param $field
+   * @param string $field
    *   The field name to use for the sequence.
    *
-   * @return
+   * @return string
    *   A table prefix-parsed string for the sequence name.
    */
   public function makeSequenceName($table, $field) {
@@ -441,10 +453,10 @@ abstract class Connection {
    *
    * The comment string will be sanitized to avoid SQL injection attacks.
    *
-   * @param $comments
+   * @param string[] $comments
    *   An array of query comment strings.
    *
-   * @return
+   * @return string
    *   A sanitized comment string.
    */
   public function makeComment($comments) {
@@ -483,10 +495,10 @@ abstract class Connection {
    * Unless the comment is sanitised first, the SQL server would drop the
    * node table and ignore the rest of the SQL statement.
    *
-   * @param $comment
+   * @param string $comment
    *   A query comment string.
    *
-   * @return
+   * @return string
    *   A sanitized version of the query comment string.
    */
   protected function filterComment($comment = '') {
@@ -500,7 +512,7 @@ abstract class Connection {
    * query. All queries executed by Drupal are executed as PDO prepared
    * statements.
    *
-   * @param $query
+   * @param string|\Drupal\Core\Database\StatementInterface $query
    *   The query to execute. In most cases this will be a string containing
    *   an SQL query with placeholders. An already-prepared instance of
    *   StatementInterface may also be passed in order to allow calling
@@ -509,26 +521,36 @@ abstract class Connection {
    *   It is extremely rare that module code will need to pass a statement
    *   object to this method. It is used primarily for database drivers for
    *   databases that require special LOB field handling.
-   * @param $args
+   * @param array $args
    *   An array of arguments for the prepared statement. If the prepared
    *   statement uses ? placeholders, this array must be an indexed array.
    *   If it contains named placeholders, it must be an associative array.
-   * @param $options
-   *   An associative array of options to control how the query is run. See
-   *   the documentation for DatabaseConnection::defaultOptions() for details.
+   * @param array $options
+   *   An associative array of options to control how the query is run. The
+   *   given options will be merged with self::defaultOptions(). See the
+   *   documentation for self::defaultOptions() for details.
+   *   Typically, $options['return'] will be set by a default or by a query
+   *   builder, and should not be set by a user.
    *
    * @return \Drupal\Core\Database\StatementInterface|int|null
-   *   This method will return one of: the executed statement, the number of
-   *   rows affected by the query (not the number matched), or the generated
-   *   insert ID of the last query, depending on the value of
-   *   $options['return']. Typically that value will be set by default or a
-   *   query builder and should not be set by a user. If there is an error,
-   *   this method will return NULL and may throw an exception if
-   *   $options['throw_exception'] is TRUE.
+   *   This method will return one of the following:
+   *   - If either $options['return'] === self::RETURN_STATEMENT, or
+   *     $options['return'] is not set (due to self::defaultOptions()),
+   *     returns the executed statement.
+   *   - If $options['return'] === self::RETURN_AFFECTED,
+   *     returns the number of rows affected by the query
+   *     (not the number matched).
+   *   - If $options['return'] === self::RETURN_INSERT_ID,
+   *     returns the generated insert ID of the last query.
+   *   - If either $options['return'] === self::RETURN_NULL, or
+   *     an exception occurs and $options['throw_exception'] evaluates to FALSE,
+   *     returns NULL.
    *
    * @throws \Drupal\Core\Database\DatabaseExceptionWrapper
    * @throws \Drupal\Core\Database\IntegrityConstraintViolationException
    * @throws \InvalidArgumentException
+   *
+   * @see \Drupal\Core\Database\Connection::defaultOptions()
    */
   public function query($query, array $args = array(), $options = array()) {
     // Use default values if not already set.
@@ -628,6 +650,13 @@ abstract class Connection {
    *
    * @return bool
    *   TRUE if the query was modified, FALSE otherwise.
+   *
+   * @throws \InvalidArgumentException
+   *   This exception is thrown when:
+   *   - A placeholder that ends in [] is supplied, and the supplied value is
+   *     not an array.
+   *   - A placeholder that does not end in [] is supplied, and the supplied
+   *     value is an array.
    */
   protected function expandArguments(&$query, &$args) {
     $modified = FALSE;
@@ -700,12 +729,12 @@ abstract class Connection {
   /**
    * Prepares and returns a SELECT query object.
    *
-   * @param $table
+   * @param string $table
    *   The base table for this query, that is, the first table in the FROM
    *   clause. This table will also be used as the "base" table for query_alter
    *   hook implementations.
-   * @param $alias
-   *   The alias of the base table of this query.
+   * @param string $alias
+   *   (optional) The alias of the base table of this query.
    * @param $options
    *   An array of options on the query.
    *
@@ -724,8 +753,10 @@ abstract class Connection {
   /**
    * Prepares and returns an INSERT query object.
    *
-   * @param $options
-   *   An array of options on the query.
+   * @param string $table
+   *   The table to use for the insert statement.
+   * @param array $options
+   *   (optional) An array of options on the query.
    *
    * @return \Drupal\Core\Database\Query\Insert
    *   A new Insert query object.
@@ -740,8 +771,10 @@ abstract class Connection {
   /**
    * Prepares and returns a MERGE query object.
    *
-   * @param $options
-   *   An array of options on the query.
+   * @param string $table
+   *   The table to use for the merge statement.
+   * @param array $options
+   *   (optional) An array of options on the query.
    *
    * @return \Drupal\Core\Database\Query\Merge
    *   A new Merge query object.
@@ -757,8 +790,10 @@ abstract class Connection {
   /**
    * Prepares and returns an UPDATE query object.
    *
-   * @param $options
-   *   An array of options on the query.
+   * @param string $table
+   *   The table to use for the update statement.
+   * @param array $options
+   *   (optional) An array of options on the query.
    *
    * @return \Drupal\Core\Database\Query\Update
    *   A new Update query object.
@@ -773,8 +808,10 @@ abstract class Connection {
   /**
    * Prepares and returns a DELETE query object.
    *
-   * @param $options
-   *   An array of options on the query.
+   * @param string $table
+   *   The table to use for the delete statement.
+   * @param array $options
+   *   (optional) An array of options on the query.
    *
    * @return \Drupal\Core\Database\Query\Delete
    *   A new Delete query object.
@@ -789,8 +826,10 @@ abstract class Connection {
   /**
    * Prepares and returns a TRUNCATE query object.
    *
-   * @param $options
-   *   An array of options on the query.
+   * @param string $table
+   *   The table to use for the truncate statement.
+   * @param array $options
+   *   (optional) An array of options on the query.
    *
    * @return \Drupal\Core\Database\Query\Truncate
    *   A new Truncate query object.
@@ -825,8 +864,11 @@ abstract class Connection {
    * For some database drivers, it may also wrap the database name in
    * database-specific escape characters.
    *
+   * @param string $database
+   *   An unsanitized database name.
+   *
    * @return string
-   *   The sanitized database name string.
+   *   The sanitized database name.
    */
   public function escapeDatabase($database) {
     return preg_replace('/[^A-Za-z0-9_.]+/', '', $database);
@@ -839,8 +881,11 @@ abstract class Connection {
    * For some database drivers, it may also wrap the table name in
    * database-specific escape characters.
    *
-   * @return
-   *   The sanitized table name string.
+   * @param string $table
+   *   An unsanitized table name.
+   *
+   * @return string
+   *   The sanitized table name.
    */
   public function escapeTable($table) {
     return preg_replace('/[^A-Za-z0-9_.]+/', '', $table);
@@ -853,8 +898,11 @@ abstract class Connection {
    * For some database drivers, it may also wrap the field name in
    * database-specific escape characters.
    *
-   * @return
-   *   The sanitized field name string.
+   * @param string $field
+   *   An unsanitized field name.
+   *
+   * @return string
+   *   The sanitized field name.
    */
   public function escapeField($field) {
     return preg_replace('/[^A-Za-z0-9_.]+/', '', $field);
@@ -868,8 +916,11 @@ abstract class Connection {
    * DatabaseConnection::escapeTable(), this doesn't allow the period (".")
    * because that is not allowed in aliases.
    *
-   * @return
-   *   The sanitized field name string.
+   * @param string $field
+   *   An unsanitized alias name.
+   *
+   * @return string
+   *   The sanitized alias name.
    */
   public function escapeAlias($field) {
     return preg_replace('/[^A-Za-z0-9_]+/', '', $field);
@@ -894,10 +945,10 @@ abstract class Connection {
    * Backslash is defined as escape character for LIKE patterns in
    * Drupal\Core\Database\Query\Condition::mapConditionOperator().
    *
-   * @param $string
+   * @param string $string
    *   The string to escape.
    *
-   * @return
+   * @return string
    *   The escaped string.
    */
   public function escapeLike($string) {
@@ -907,7 +958,7 @@ abstract class Connection {
   /**
    * Determines if there is an active transaction open.
    *
-   * @return
+   * @return bool
    *   TRUE if we're currently in a transaction, FALSE otherwise.
    */
   public function inTransaction() {
@@ -915,7 +966,10 @@ abstract class Connection {
   }
 
   /**
-   * Determines current transaction depth.
+   * Determines the current transaction depth.
+   *
+   * @return int
+   *   The current transaction depth.
    */
   public function transactionDepth() {
     return count($this->transactionLayers);
@@ -924,8 +978,8 @@ abstract class Connection {
   /**
    * Returns a new DatabaseTransaction object on this connection.
    *
-   * @param $name
-   *   Optional name of the savepoint.
+   * @param string $name
+   *   (optional) The name of the savepoint.
    *
    * @return \Drupal\Core\Database\Transaction
    *   A Transaction object.
@@ -942,10 +996,11 @@ abstract class Connection {
    *
    * This method throws an exception if no transaction is active.
    *
-   * @param $savepoint_name
-   *   The name of the savepoint. The default, 'drupal_transaction', will roll
-   *   the entire transaction back.
+   * @param string $savepoint_name
+   *   (optional) The name of the savepoint. The default, 'drupal_transaction',
+   *    will roll the entire transaction back.
    *
+   * @throws \Drupal\Core\Database\TransactionOutOfOrderException
    * @throws \Drupal\Core\Database\TransactionNoActiveException
    *
    * @see \Drupal\Core\Database\Transaction::rollback()
@@ -997,6 +1052,9 @@ abstract class Connection {
    *
    * If no transaction is already active, we begin a new transaction.
    *
+   * @param string $name
+   *   The name of the transaction.
+   *
    * @throws \Drupal\Core\Database\TransactionNameNonUniqueException
    *
    * @see \Drupal\Core\Database\Transaction
@@ -1026,8 +1084,8 @@ abstract class Connection {
    * back the transaction as necessary. If no transaction is active, we return
    * because the transaction may have manually been rolled back.
    *
-   * @param $name
-   *   The name of the savepoint
+   * @param string $name
+   *   The name of the savepoint.
    *
    * @throws \Drupal\Core\Database\TransactionNoActiveException
    * @throws \Drupal\Core\Database\TransactionCommitFailedException
@@ -1083,16 +1141,17 @@ abstract class Connection {
    * separate parameters so that they can be properly escaped to avoid SQL
    * injection attacks.
    *
-   * @param $query
+   * @param string $query
    *   A string containing an SQL query.
-   * @param $args
-   *   An array of values to substitute into the query at placeholder markers.
-   * @param $from
+   * @param int $from
    *   The first result row to return.
-   * @param $count
+   * @param int $count
    *   The maximum number of result rows to return.
-   * @param $options
-   *   An array of options on the query.
+   * @param array $args
+   *   (optional) An array of values to substitute into the query at placeholder
+   *    markers.
+   * @param array $options
+   *   (optional) An array of options on the query.
    *
    * @return \Drupal\Core\Database\StatementInterface
    *   A database query result resource, or NULL if the query was not executed
@@ -1103,7 +1162,7 @@ abstract class Connection {
   /**
    * Generates a temporary table name.
    *
-   * @return
+   * @return string
    *   A table name.
    */
   protected function generateTemporaryTableName() {
@@ -1122,15 +1181,17 @@ abstract class Connection {
    * Note that if you need to know how many results were returned, you should do
    * a SELECT COUNT(*) on the temporary table afterwards.
    *
-   * @param $query
+   * @param string $query
    *   A string containing a normal SELECT SQL query.
-   * @param $args
-   *   An array of values to substitute into the query at placeholder markers.
-   * @param $options
-   *   An associative array of options to control how the query is run. See
-   *   the documentation for DatabaseConnection::defaultOptions() for details.
+   * @param array $args
+   *   (optional) An array of values to substitute into the query at placeholder
+   *   markers.
+   * @param array $options
+   *   (optional) An associative array of options to control how the query is
+   *   run. See the documentation for DatabaseConnection::defaultOptions() for
+   *   details.
    *
-   * @return
+   * @return string
    *   The name of the temporary table.
    */
   abstract function queryTemporary($query, array $args = array(), array $options = array());
@@ -1142,6 +1203,9 @@ abstract class Connection {
    * instance, there could be two MySQL drivers, mysql and mysql_mock. This
    * function would return different values for each, but both would return
    * "mysql" for databaseType().
+   *
+   * @return string
+   *   The type of database driver.
    */
   abstract public function driver();
 
@@ -1155,7 +1219,7 @@ abstract class Connection {
   /**
    * Determines if this driver supports transactions.
    *
-   * @return
+   * @return bool
    *   TRUE if this connection supports transactions, FALSE otherwise.
    */
   public function supportsTransactions() {
@@ -1167,7 +1231,7 @@ abstract class Connection {
    *
    * DDL queries are those that change the schema, such as ALTER queries.
    *
-   * @return
+   * @return bool
    *   TRUE if this connection supports transactions for DDL queries, FALSE
    *   otherwise.
    */
@@ -1199,7 +1263,7 @@ abstract class Connection {
    * overridable lookup function. Database connections should define only
    * those operators they wish to be handled differently than the default.
    *
-   * @param $operator
+   * @param string $operator
    *   The condition operator, such as "IN", "BETWEEN", etc. Case-sensitive.
    *
    * @return
@@ -1226,7 +1290,7 @@ abstract class Connection {
   }
 
   /**
-   * Retrieves an unique id from a given sequence.
+   * Retrieves an unique ID from a given sequence.
    *
    * Use this function if for some reason you can't use a serial field. For
    * example, MySQL has no ways of reading of the current value of a sequence
@@ -1234,9 +1298,9 @@ abstract class Connection {
    * value. Or sometimes you just need a unique integer.
    *
    * @param $existing_id
-   *   After a database import, it might be that the sequences table is behind,
-   *   so by passing in the maximum existing id, it can be assured that we
-   *   never issue the same id.
+   *   (optional) After a database import, it might be that the sequences table
+   *   is behind, so by passing in the maximum existing ID, it can be assured
+   *   that we never issue the same ID.
    *
    * @return
    *   An integer number larger than any number returned by earlier calls and

core/lib/Drupal/Core/Database/Driver/mysql/Connection.php

@@ -14,6 +14,7 @@ use Drupal\Core\Database\DatabaseNotFoundException;
 use Drupal\Core\Database\TransactionCommitFailedException;
 use Drupal\Core\Database\DatabaseException;
 use Drupal\Core\Database\Connection as DatabaseConnection;
+use Drupal\Component\Utility\Unicode;
 
 /**
  * @addtogroup database
@@ -34,6 +35,16 @@ class Connection extends DatabaseConnection {
    */
   protected $needsCleanup = FALSE;
 
+  /**
+   * The minimal possible value for the max_allowed_packet setting of MySQL.
+   *
+   * @link https://mariadb.com/kb/en/mariadb/server-system-variables/#max_allowed_packet
+   * @link https://dev.mysql.com/doc/refman/5.7/en/server-system-variables.html#sysvar_max_allowed_packet
+   *
+   * @var int
+   */
+  const MIN_MAX_ALLOWED_PACKET = 1024;
+
   /**
    * Constructs a Connection object.
    */
@@ -49,6 +60,24 @@ class Connection extends DatabaseConnection {
     $this->connectionOptions = $connection_options;
   }
 
+  /**
+   * {@inheritdoc}
+   */
+  public function query($query, array $args = array(), $options = array()) {
+    try {
+      return parent::query($query, $args, $options);
+    } catch (DatabaseException $e) {
+      if ($e->getPrevious()->errorInfo[1] == 1153) {
+        // If a max_allowed_packet error occurs the message length is truncated.
+        // This should prevent the error from recurring if the exception is
+        // logged to the database using dblog or the like.
+        $message = Unicode::truncateBytes($e->getMessage(), self::MIN_MAX_ALLOWED_PACKET);
+        $e = new DatabaseExceptionWrapper($message, $e->getCode(), $e->getPrevious());
+      }
+      throw $e;
+    }
+  }
+
   /**
    * {@inheritdoc}
    */
@@ -278,6 +307,7 @@ class Connection extends DatabaseConnection {
       }
     }
   }
+
 }
 
 

core/lib/Drupal/Core/Database/Driver/pgsql/Connection.php

@@ -31,6 +31,27 @@ class Connection extends DatabaseConnection {
    */
   const DATABASE_NOT_FOUND = 7;
 
+  /**
+   * The list of PostgreSQL reserved key words.
+   *
+   * @see http://www.postgresql.org/docs/9.4/static/sql-keywords-appendix.html
+   */
+  protected $postgresqlReservedKeyWords = ['all', 'analyse', 'analyze', 'and',
+  'any', 'array', 'as', 'asc', 'asymmetric', 'authorization', 'binary', 'both',
+  'case', 'cast', 'check', 'collate', 'collation', 'column', 'concurrently',
+  'constraint', 'create', 'cross', 'current_catalog', 'current_date',
+  'current_role', 'current_schema', 'current_time', 'current_timestamp',
+  'current_user', 'default', 'deferrable', 'desc', 'distinct', 'do', 'else',
+  'end', 'except', 'false', 'fetch', 'for', 'foreign', 'freeze', 'from', 'full',
+  'grant', 'group', 'having', 'ilike', 'in', 'initially', 'inner', 'intersect',
+  'into', 'is', 'isnull', 'join', 'lateral', 'leading', 'left', 'like', 'limit',
+  'localtime', 'localtimestamp', 'natural', 'not', 'notnull', 'null', 'offset',
+  'on', 'only', 'or', 'order', 'outer', 'over', 'overlaps', 'placing',
+  'primary', 'references', 'returning', 'right', 'select', 'session_user',
+  'similar', 'some', 'symmetric', 'table', 'then', 'to', 'trailing', 'true',
+  'union', 'unique', 'user', 'using', 'variadic', 'verbose', 'when', 'where',
+  'window', 'with'];
+
   /**
    * Constructs a connection object.
    */
@@ -167,6 +188,10 @@ class Connection extends DatabaseConnection {
       // Quote the field name for case-sensitivity.
       $escaped = '"' . $escaped . '"';
     }
+    elseif (in_array(strtolower($escaped), $this->postgresqlReservedKeyWords)) {
+      // Quote the field name for PostgreSQL reserved key words.
+      $escaped = '"' . $escaped . '"';
+    }
 
     return $escaped;
   }
@@ -181,6 +206,10 @@ class Connection extends DatabaseConnection {
     if (preg_match('/[A-Z]/', $escaped)) {
       $escaped = '"' . $escaped . '"';
     }
+    elseif (in_array(strtolower($escaped), $this->postgresqlReservedKeyWords)) {
+      // Quote the alias name for PostgreSQL reserved key words.
+      $escaped = '"' . $escaped . '"';
+    }
 
     return $escaped;
   }
@@ -195,6 +224,10 @@ class Connection extends DatabaseConnection {
     if (preg_match('/[A-Z]/', $escaped)) {
       $escaped = '"' . $escaped . '"';
     }
+    elseif (in_array(strtolower($escaped), $this->postgresqlReservedKeyWords)) {
+      // Quote the table name for PostgreSQL reserved key words.
+      $escaped = '"' . $escaped . '"';
+    }
 
     return $escaped;
   }

core/lib/Drupal/Core/Database/Driver/pgsql/Insert.php

@@ -117,6 +117,8 @@ class Insert extends QueryInsert {
     // Default fields are always placed first for consistency.
     $insert_fields = array_merge($this->defaultFields, $this->insertFields);
 
+    $insert_fields = array_map(function($f) { return $this->connection->escapeField($f); }, $insert_fields);
+
     // If we're selecting from a SelectQuery, finish building the query and
     // pass it back, as any remaining options are irrelevant.
     if (!empty($this->fromQuery)) {
@@ -154,4 +156,5 @@ class Insert extends QueryInsert {
 
     return $query;
   }
+
 }

core/lib/Drupal/Core/Database/Driver/pgsql/Install/Tasks.php

@@ -51,7 +51,7 @@ class Tasks extends InstallTasks {
    * {@inheritdoc}
    */
   public function minimumVersion() {
-    return '8.3';
+    return '9.1.2';
   }
 
   /**

core/lib/Drupal/Core/Database/Driver/pgsql/Schema.php

@@ -329,7 +329,7 @@ class Schema extends DatabaseSchema {
     }
 
     if (!empty($field['unsigned'])) {
-      // Unsigned datatypes are not supported in PostgreSQL 8.3. In MySQL,
+      // Unsigned datatypes are not supported in PostgreSQL 9.1. In MySQL,
       // they are used to ensure a positive number is inserted and it also
       // doubles the maximum integer size that can be stored in a field.
       // The PostgreSQL schema in Drupal creates a check constraint
@@ -569,7 +569,7 @@ class Schema extends DatabaseSchema {
   }
 
   public function indexExists($table, $name) {
-    // Details http://www.postgresql.org/docs/8.3/interactive/view-pg-indexes.html
+    // Details http://www.postgresql.org/docs/9.1/interactive/view-pg-indexes.html
     $index_name = $this->ensureIdentifiersLength($table, $name, 'idx');
     // Remove leading and trailing quotes because the index name is in a WHERE
     // clause and not used as an identifier.

core/lib/Drupal/Core/Database/Driver/sqlite/Statement.php

@@ -22,7 +22,7 @@ use Drupal\Core\Database\StatementInterface;
 class Statement extends StatementPrefetch implements StatementInterface {
 
   /**
-   * SQLite specific implementation of getStatement().
+   * {@inheritdoc}
    *
    * The PDO SQLite layer doesn't replace numeric placeholders in queries
    * correctly, and this makes numeric expressions (such as COUNT(*) >= :count)
@@ -87,6 +87,9 @@ class Statement extends StatementPrefetch implements StatementInterface {
     return $this->pdoConnection->prepare($query);
   }
 
+  /**
+   * {@inheritdoc}
+   */
   public function execute($args = array(), $options = array()) {
     try {
       $return = parent::execute($args, $options);

core/lib/Drupal/Core/Database/Query/Delete.php

@@ -17,6 +17,8 @@ use Drupal\Core\Database\Connection;
  */
 class Delete extends Query implements ConditionInterface {
 
+  use QueryConditionTrait;
+
   /**
    * The table from which to delete.
    *
@@ -24,15 +26,6 @@ class Delete extends Query implements ConditionInterface {
    */
   protected $table;
 
-  /**
-   * The condition object for this query.
-   *
-   * Condition handling is handled via composition.
-   *
-   * @var Condition
-   */
-  protected $condition;
-
   /**
    * Constructs a Delete object.
    *
@@ -51,82 +44,6 @@ class Delete extends Query implements ConditionInterface {
     $this->condition = new Condition('AND');
   }
 
-  /**
-   * Implements Drupal\Core\Database\Query\ConditionInterface::condition().
-   */
-  public function condition($field, $value = NULL, $operator = '=') {
-    $this->condition->condition($field, $value, $operator);
-    return $this;
-  }
-
-  /**
-   * Implements Drupal\Core\Database\Query\ConditionInterface::isNull().
-   */
-  public function isNull($field) {
-    $this->condition->isNull($field);
-    return $this;
-  }
-
-  /**
-   * Implements Drupal\Core\Database\Query\ConditionInterface::isNotNull().
-   */
-  public function isNotNull($field) {
-    $this->condition->isNotNull($field);
-    return $this;
-  }
-
-  /**
-   * Implements Drupal\Core\Database\Query\ConditionInterface::exists().
-   */
-  public function exists(SelectInterface $select) {
-    $this->condition->exists($select);
-    return $this;
-  }
-
-  /**
-   * Implements Drupal\Core\Database\Query\ConditionInterface::notExists().
-   */
-  public function notExists(SelectInterface $select) {
-    $this->condition->notExists($select);
-    return $this;
-  }
-
-  /**
-   * Implements Drupal\Core\Database\Query\ConditionInterface::conditions().
-   */
-  public function &conditions() {
-    return $this->condition->conditions();
-  }
-
-  /**
-   * Implements Drupal\Core\Database\Query\ConditionInterface::arguments().
-   */
-  public function arguments() {
-    return $this->condition->arguments();
-  }
-
-  /**
-   * Implements Drupal\Core\Database\Query\ConditionInterface::where().
-   */
-  public function where($snippet, $args = array()) {
-    $this->condition->where($snippet, $args);
-    return $this;
-  }
-
-  /**
-   * Implements Drupal\Core\Database\Query\ConditionInterface::compile().
-   */
-  public function compile(Connection $connection, PlaceholderInterface $queryPlaceholder) {
-    return $this->condition->compile($connection, $queryPlaceholder);
-  }
-
-  /**
-   * Implements Drupal\Core\Database\Query\ConditionInterface::compiled().
-   */
-  public function compiled() {
-    return $this->condition->compiled();
-  }
-
   /**
    * Executes the DELETE query.
    *

core/lib/Drupal/Core/Database/Query/Merge.php

@@ -49,6 +49,9 @@ use Drupal\Core\Database\IntegrityConstraintViolationException;
  * fields() and updateFields().
  */
 class Merge extends Query implements ConditionInterface {
+
+  use QueryConditionTrait;
+
   /**
    * Returned by execute() if an INSERT query has been executed.
    */
@@ -339,82 +342,6 @@ class Merge extends Query implements ConditionInterface {
     return $this;
   }
 
-  /**
-   * Implements Drupal\Core\Database\Query\ConditionInterface::condition().
-   */
-  public function condition($field, $value = NULL, $operator = '=') {
-    $this->condition->condition($field, $value, $operator);
-    return $this;
-  }
-
-  /**
-   * Implements Drupal\Core\Database\Query\ConditionInterface::isNull().
-   */
-  public function isNull($field) {
-    $this->condition->isNull($field);
-    return $this;
-  }
-
-  /**
-   * Implements Drupal\Core\Database\Query\ConditionInterface::isNotNull().
-   */
-  public function isNotNull($field) {
-    $this->condition->isNotNull($field);
-    return $this;
-  }
-
-  /**
-   * Implements Drupal\Core\Database\Query\ConditionInterface::exists().
-   */
-  public function exists(SelectInterface $select) {
-    $this->condition->exists($select);
-    return $this;
-  }
-
-  /**
-   * Implements Drupal\Core\Database\Query\ConditionInterface::notExists().
-   */
-  public function notExists(SelectInterface $select) {
-    $this->condition->notExists($select);
-    return $this;
-  }
-
-  /**
-   * Implements Drupal\Core\Database\Query\ConditionInterface::conditions().
-   */
-  public function &conditions() {
-    return $this->condition->conditions();
-  }
-
-  /**
-   * Implements Drupal\Core\Database\Query\ConditionInterface::arguments().
-   */
-  public function arguments() {
-    return $this->condition->arguments();
-  }
-
-  /**
-   * Implements Drupal\Core\Database\Query\ConditionInterface::where().
-   */
-  public function where($snippet, $args = array()) {
-    $this->condition->where($snippet, $args);
-    return $this;
-  }
-
-  /**
-   * Implements Drupal\Core\Database\Query\ConditionInterface::compile().
-   */
-  public function compile(Connection $connection, PlaceholderInterface $queryPlaceholder) {
-    return $this->condition->compile($connection, $queryPlaceholder);
-  }
-
-  /**
-   * Implements Drupal\Core\Database\Query\ConditionInterface::compiled().
-   */
-  public function compiled() {
-    return $this->condition->compiled();
-  }
-
   /**
    * Implements PHP magic __toString method to convert the query to a string.
    *

core/lib/Drupal/Core/Database/Query/Query.php

@@ -180,25 +180,4 @@ abstract class Query implements PlaceholderInterface {
     return $this->comments;
   }
 
-  /**
-   * {@inheritdoc}
-   */
-  public function conditionGroupFactory($conjunction = 'AND') {
-    return new Condition($conjunction);
-  }
-
-  /**
-   * {@inheritdoc}
-   */
-  public function andConditionGroup() {
-    return $this->conditionGroupFactory('AND');
-  }
-
-  /**
-   * {@inheritdoc}
-   */
-  public function orConditionGroup() {
-    return $this->conditionGroupFactory('OR');
-  }
-
 }

core/lib/Drupal/Core/Database/Query/QueryConditionTrait.php

@@ -0,0 +1,125 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\Core\Database\Query\QueryConditionTrait.
+ */
+
+namespace Drupal\Core\Database\Query;
+
+use Drupal\Core\Database\Connection;
+
+/**
+ * Provides an implementation of ConditionInterface.
+ *
+ * @see \Drupal\Core\Database\Query\ConditionInterface
+ */
+trait QueryConditionTrait {
+
+  /**
+   * The condition object for this query.
+   *
+   * Condition handling is handled via composition.
+   *
+   * @var \Drupal\Core\Database\Query\Condition
+   */
+  protected $condition;
+
+  /**
+   * Implements Drupal\Core\Database\Query\ConditionInterface::condition().
+   */
+  public function condition($field, $value = NULL, $operator = '=') {
+    $this->condition->condition($field, $value, $operator);
+    return $this;
+  }
+
+  /**
+   * Implements Drupal\Core\Database\Query\ConditionInterface::isNull().
+   */
+  public function isNull($field) {
+    $this->condition->isNull($field);
+    return $this;
+  }
+
+  /**
+   * Implements Drupal\Core\Database\Query\ConditionInterface::isNotNull().
+   */
+  public function isNotNull($field) {
+    $this->condition->isNotNull($field);
+    return $this;
+  }
+
+  /**
+   * Implements Drupal\Core\Database\Query\ConditionInterface::exists().
+   */
+  public function exists(SelectInterface $select) {
+    $this->condition->exists($select);
+    return $this;
+  }
+
+  /**
+   * Implements Drupal\Core\Database\Query\ConditionInterface::notExists().
+   */
+  public function notExists(SelectInterface $select) {
+    $this->condition->notExists($select);
+    return $this;
+  }
+
+  /**
+   * Implements Drupal\Core\Database\Query\ConditionInterface::conditions().
+   */
+  public function &conditions() {
+    return $this->condition->conditions();
+  }
+
+  /**
+   * Implements Drupal\Core\Database\Query\ConditionInterface::arguments().
+   */
+  public function arguments() {
+    return $this->condition->arguments();
+  }
+
+  /**
+   * Implements Drupal\Core\Database\Query\ConditionInterface::where().
+   */
+  public function where($snippet, $args = array()) {
+    $this->condition->where($snippet, $args);
+    return $this;
+  }
+
+  /**
+   * Implements Drupal\Core\Database\Query\ConditionInterface::compile().
+   */
+  public function compile(Connection $connection, PlaceholderInterface $queryPlaceholder) {
+    $this->condition->compile($connection, $queryPlaceholder);
+  }
+
+  /**
+   * Implements Drupal\Core\Database\Query\ConditionInterface::compiled().
+   */
+  public function compiled() {
+    return $this->condition->compiled();
+  }
+
+  /**
+   * Implements Drupal\Core\Database\Query\ConditionInterface::conditionGroupFactory().
+   */
+  public function conditionGroupFactory($conjunction = 'AND') {
+    return new Condition($conjunction);
+  }
+
+  /**
+   * Implements Drupal\Core\Database\Query\ConditionInterface::andConditionGroup().
+   */
+  public function andConditionGroup() {
+    return $this->conditionGroupFactory('AND');
+  }
+
+  /**
+   * Implements Drupal\Core\Database\Query\ConditionInterface::orConditionGroup().
+   */
+  public function orConditionGroup() {
+    return $this->conditionGroupFactory('OR');
+  }
+
+}

core/lib/Drupal/Core/Database/Query/Select.php

@@ -18,6 +18,8 @@ use Drupal\Core\Database\Connection;
  */
 class Select extends Query implements SelectInterface {
 
+  use QueryConditionTrait;
+
   /**
    * The fields to SELECT.
    *
@@ -71,13 +73,6 @@ class Select extends Query implements SelectInterface {
    */
   protected $group = array();
 
-  /**
-   * The conditional object for the WHERE clause.
-   *
-   * @var \Drupal\Core\Database\Query\Condition
-   */
-  protected $where;
-
   /**
    * The conditional object for the HAVING clause.
    *
@@ -139,7 +134,7 @@ class Select extends Query implements SelectInterface {
     $options['return'] = Database::RETURN_STATEMENT;
     parent::__construct($connection, $options);
     $conjunction = isset($options['conjunction']) ? $options['conjunction'] : 'AND';
-    $this->where = new Condition($conjunction);
+    $this->condition = new Condition($conjunction);
     $this->having = new Condition($conjunction);
     $this->addJoin(NULL, $table, $alias);
   }
@@ -188,21 +183,6 @@ class Select extends Query implements SelectInterface {
     return isset($this->alterMetaData[$key]) ? $this->alterMetaData[$key] : NULL;
   }
 
-  /**
-   * {@inheritdoc}
-   */
-  public function condition($field, $value = NULL, $operator = '=') {
-    $this->where->condition($field, $value, $operator);
-    return $this;
-  }
-
-  /**
-   * {@inheritdoc}
-   */
-  public function &conditions() {
-    return $this->where->conditions();
-  }
-
   /**
    * {@inheritdoc}
    */
@@ -211,7 +191,7 @@ class Select extends Query implements SelectInterface {
       return NULL;
     }
 
-    $args = $this->where->arguments() + $this->having->arguments();
+    $args = $this->condition->arguments() + $this->having->arguments();
 
     foreach ($this->tables as $table) {
       if ($table['arguments']) {
@@ -238,51 +218,11 @@ class Select extends Query implements SelectInterface {
     return $args;
   }
 
-  /**
-   * {@inheritdoc}
-   */
-  public function where($snippet, $args = array()) {
-    $this->where->where($snippet, $args);
-    return $this;
-  }
-
-  /**
-   * {@inheritdoc}
-   */
-  public function isNull($field) {
-    $this->where->isNull($field);
-    return $this;
-  }
-
-  /**
-   * {@inheritdoc}
-   */
-  public function isNotNull($field) {
-    $this->where->isNotNull($field);
-    return $this;
-  }
-
-  /**
-   * {@inheritdoc}
-   */
-  public function exists(SelectInterface $select) {
-    $this->where->exists($select);
-    return $this;
-  }
-
-  /**
-   * {@inheritdoc}
-   */
-  public function notExists(SelectInterface $select) {
-    $this->where->notExists($select);
-    return $this;
-  }
-
   /**
    * {@inheritdoc}
    */
   public function compile(Connection $connection, PlaceholderInterface $queryPlaceholder) {
-    $this->where->compile($connection, $queryPlaceholder);
+    $this->condition->compile($connection, $queryPlaceholder);
     $this->having->compile($connection, $queryPlaceholder);
 
     foreach ($this->tables as $table) {
@@ -302,7 +242,7 @@ class Select extends Query implements SelectInterface {
    * {@inheritdoc}
    */
   public function compiled() {
-    if (!$this->where->compiled() || !$this->having->compiled()) {
+    if (!$this->condition->compiled() || !$this->having->compiled()) {
       return FALSE;
     }
 
@@ -463,6 +403,13 @@ class Select extends Query implements SelectInterface {
     return $this->connection->escapeLike($string);
   }
 
+  /**
+   * {@inheritdoc}
+   */
+  public function escapeField($string) {
+    return $this->connection->escapeField($string);
+  }
+
   /**
    * {@inheritdoc}
    */
@@ -885,9 +832,9 @@ class Select extends Query implements SelectInterface {
     }
 
     // WHERE
-    if (count($this->where)) {
+    if (count($this->condition)) {
       // There is an implicit string cast on $this->condition.
-      $query .= "\nWHERE " . $this->where;
+      $query .= "\nWHERE " . $this->condition;
     }
 
     // GROUP BY
@@ -943,7 +890,7 @@ class Select extends Query implements SelectInterface {
     // want to clone the database connection object as that would duplicate the
     // connection itself.
 
-    $this->where = clone($this->where);
+    $this->condition = clone($this->condition);
     $this->having = clone($this->having);
     foreach ($this->union as $key => $aggregate) {
       $this->union[$key]['query'] = clone($aggregate['query']);

core/lib/Drupal/Core/Database/Query/SelectExtender.php

@@ -210,6 +210,14 @@ class SelectExtender implements SelectInterface {
     return $this->query->escapeLike($string);
   }
 
+  /**
+   * {@inheritdoc}
+   */
+  public function escapeField($string) {
+    $this->query->escapeField($string);
+    return $this;
+  }
+
   public function getArguments(PlaceholderInterface $queryPlaceholder = NULL) {
     return $this->query->getArguments($queryPlaceholder);
   }

core/lib/Drupal/Core/Database/Query/SelectInterface.php

@@ -140,6 +140,18 @@ interface SelectInterface extends ConditionInterface, AlterableInterface, Extend
    */
   public function escapeLike($string);
 
+  /**
+   * Escapes a field name string.
+   *
+   * Force all field names to be strictly alphanumeric-plus-underscore.
+   * For some database drivers, it may also wrap the field name in
+   * database-specific escape characters.
+   *
+   * @return
+   *   The sanitized field name string.
+   */
+  public function escapeField($string);
+
   /**
    * Compiles and returns an associative array of the arguments for this prepared statement.
    *
@@ -632,4 +644,5 @@ interface SelectInterface extends ConditionInterface, AlterableInterface, Extend
    *   The called object.
    */
   public function forUpdate($set = TRUE);
+
 }

core/lib/Drupal/Core/Database/Query/Update.php

@@ -17,6 +17,8 @@ use Drupal\Core\Database\Connection;
  */
 class Update extends Query implements ConditionInterface {
 
+  use QueryConditionTrait;
+
   /**
    * The table to update.
    *
@@ -38,15 +40,6 @@ class Update extends Query implements ConditionInterface {
    */
   protected $arguments = array();
 
-  /**
-   * The condition object for this query.
-   *
-   * Condition handling is handled via composition.
-   *
-   * @var \Drupal\Core\Database\Query\Condition
-   */
-  protected $condition;
-
   /**
    * Array of fields to update to an expression in case of a duplicate record.
    *
@@ -80,82 +73,6 @@ class Update extends Query implements ConditionInterface {
     $this->condition = new Condition('AND');
   }
 
-  /**
-   * Implements Drupal\Core\Database\Query\ConditionInterface::condition().
-   */
-  public function condition($field, $value = NULL, $operator = '=') {
-    $this->condition->condition($field, $value, $operator);
-    return $this;
-  }
-
-  /**
-   * Implements Drupal\Core\Database\Query\ConditionInterface::isNull().
-   */
-  public function isNull($field) {
-    $this->condition->isNull($field);
-    return $this;
-  }
-
-  /**
-   * Implements Drupal\Core\Database\Query\ConditionInterface::isNotNull().
-   */
-  public function isNotNull($field) {
-    $this->condition->isNotNull($field);
-    return $this;
-  }
-
-  /**
-   * Implements Drupal\Core\Database\Query\ConditionInterface::exists().
-   */
-  public function exists(SelectInterface $select) {
-    $this->condition->exists($select);
-    return $this;
-  }
-
-  /**
-   * Implements Drupal\Core\Database\Query\ConditionInterface::notExists().
-   */
-  public function notExists(SelectInterface $select) {
-    $this->condition->notExists($select);
-    return $this;
-  }
-
-  /**
-   * Implements Drupal\Core\Database\Query\ConditionInterface::conditions().
-   */
-  public function &conditions() {
-    return $this->condition->conditions();
-  }
-
-  /**
-   * Implements Drupal\Core\Database\Query\ConditionInterface::arguments().
-   */
-  public function arguments() {
-    return $this->condition->arguments();
-  }
-
-  /**
-   * Implements Drupal\Core\Database\Query\ConditionInterface::where().
-   */
-  public function where($snippet, $args = array()) {
-    $this->condition->where($snippet, $args);
-    return $this;
-  }
-
-  /**
-   * Implements Drupal\Core\Database\Query\ConditionInterface::compile().
-   */
-  public function compile(Connection $connection, PlaceholderInterface $queryPlaceholder) {
-    return $this->condition->compile($connection, $queryPlaceholder);
-  }
-
-  /**
-   * Implements Drupal\Core\Database\Query\ConditionInterface::compiled().
-   */
-  public function compiled() {
-    return $this->condition->compiled();
-  }
-
   /**
    * Adds a set of field->value pairs to be updated.
    *
@@ -256,13 +173,13 @@ class Update extends Query implements ConditionInterface {
         $data['expression']->compile($this->connection, $this);
         $data['expression'] = ' (' . $data['expression'] . ')';
       }
-      $update_fields[] = $field . '=' . $data['expression'];
+      $update_fields[] = $this->connection->escapeField($field) . '=' . $data['expression'];
       unset($fields[$field]);
     }
 
     $max_placeholder = 0;
     foreach ($fields as $field => $value) {
-      $update_fields[] = $field . '=:db_update_placeholder_' . ($max_placeholder++);
+      $update_fields[] = $this->connection->escapeField($field) . '=:db_update_placeholder_' . ($max_placeholder++);
     }
 
     $query = $comments . 'UPDATE {' . $this->connection->escapeTable($this->table) . '} SET ' . implode(', ', $update_fields);

core/lib/Drupal/Core/Database/Statement.php

@@ -41,6 +41,9 @@ class Statement extends \PDOStatement implements StatementInterface {
     $this->setFetchMode(\PDO::FETCH_OBJ);
   }
 
+  /**
+   * {@inheritdoc}
+   */
   public function execute($args = array(), $options = array()) {
     if (isset($options['fetch'])) {
       if (is_string($options['fetch'])) {
@@ -68,14 +71,23 @@ class Statement extends \PDOStatement implements StatementInterface {
     return $return;
   }
 
+  /**
+   * {@inheritdoc}
+   */
   public function getQueryString() {
     return $this->queryString;
   }
 
+  /**
+   * {@inheritdoc}
+   */
   public function fetchCol($index = 0) {
     return $this->fetchAll(\PDO::FETCH_COLUMN, $index);
   }
 
+  /**
+   * {@inheritdoc}
+   */
   public function fetchAllAssoc($key, $fetch = NULL) {
     $return = array();
     if (isset($fetch)) {
@@ -95,6 +107,9 @@ class Statement extends \PDOStatement implements StatementInterface {
     return $return;
   }
 
+  /**
+   * {@inheritdoc}
+   */
   public function fetchAllKeyed($key_index = 0, $value_index = 1) {
     $return = array();
     $this->setFetchMode(\PDO::FETCH_NUM);
@@ -104,11 +119,17 @@ class Statement extends \PDOStatement implements StatementInterface {
     return $return;
   }
 
+  /**
+   * {@inheritdoc}
+   */
   public function fetchField($index = 0) {
     // Call \PDOStatement::fetchColumn to fetch the field.
     return $this->fetchColumn($index);
   }
 
+  /**
+   * {@inheritdoc}
+   */
   public function fetchAssoc() {
     // Call \PDOStatement::fetch to fetch the row.
     return $this->fetch(\PDO::FETCH_ASSOC);
@@ -127,4 +148,42 @@ class Statement extends \PDOStatement implements StatementInterface {
     }
   }
 
+  /**
+   * {@inheritdoc}
+   */
+  public function setFetchMode($mode, $a1 = NULL, $a2 = array()) {
+    // Call \PDOStatement::setFetchMode to set fetch mode.
+    // \PDOStatement is picky about the number of arguments in some cases so we
+    // need to be pass the exact number of arguments we where given.
+    switch (func_num_args()) {
+      case 1:
+        return parent::setFetchMode($mode);
+      case 2:
+        return parent::setFetchMode($mode, $a1);
+      case 3:
+      default:
+        return parent::setFetchMode($mode, $a1, $a2);
+    }
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function fetchAll($mode = NULL, $column_index = NULL, $constructor_arguments = NULL) {
+    // Call \PDOStatement::fetchAll to fetch all rows.
+    // \PDOStatement is picky about the number of arguments in some cases so we
+    // need to be pass the exact number of arguments we where given.
+    switch (func_num_args()) {
+      case 0:
+        return parent::fetchAll();
+      case 1:
+        return parent::fetchAll($mode);
+      case 2:
+        return parent::fetchAll($mode, $column_index);
+      case 3:
+      default:
+        return parent::fetchAll($mode, $column_index, $constructor_arguments);
+    }
+  }
+
 }

core/lib/Drupal/Core/Database/StatementEmpty.php

@@ -28,14 +28,23 @@ class StatementEmpty implements \Iterator, StatementInterface {
    */
   public $allowRowCount = FALSE;
 
+  /**
+   * {@inheritdoc}
+   */
   public function execute($args = array(), $options = array()) {
     return FALSE;
   }
 
+  /**
+   * {@inheritdoc}
+   */
   public function getQueryString() {
     return '';
   }
 
+  /**
+   * {@inheritdoc}
+   */
   public function rowCount() {
     if ($this->allowRowCount) {
       return 0;
@@ -43,61 +52,102 @@ class StatementEmpty implements \Iterator, StatementInterface {
     throw new RowCountException();
   }
 
+  /**
+   * {@inheritdoc}
+   */
   public function setFetchMode($mode, $a1 = NULL, $a2 = array()) {
     return;
   }
 
+  /**
+   * {@inheritdoc}
+   */
   public function fetch($mode = NULL, $cursor_orientation = NULL, $cursor_offset = NULL) {
     return NULL;
   }
 
+  /**
+   * {@inheritdoc}
+   */
   public function fetchField($index = 0) {
     return NULL;
   }
 
+  /**
+   * {@inheritdoc}
+   */
   public function fetchObject() {
     return NULL;
   }
 
+  /**
+   * {@inheritdoc}
+   */
   public function fetchAssoc() {
     return NULL;
   }
 
-  function fetchAll($mode = NULL, $column_index = NULL, array $constructor_arguments = array()) {
+  /**
+   * {@inheritdoc}
+   */
+  public function fetchAll($mode = NULL, $column_index = NULL, $constructor_arguments = NULL) {
     return array();
   }
 
+  /**
+   * {@inheritdoc}
+   */
   public function fetchCol($index = 0) {
     return array();
   }
 
+  /**
+   * {@inheritdoc}
+   */
   public function fetchAllKeyed($key_index = 0, $value_index = 1) {
     return array();
   }
 
+  /**
+   * {@inheritdoc}
+   */
   public function fetchAllAssoc($key, $fetch = NULL) {
     return array();
   }
 
-  /* Implementations of Iterator. */
-
+  /**
+   * {@inheritdoc}
+   */
   public function current() {
     return NULL;
   }
 
+  /**
+   * {@inheritdoc}
+   */
   public function key() {
     return NULL;
   }
 
+  /**
+   * {@inheritdoc}
+   */
   public function rewind() {
     // Nothing to do: our DatabaseStatement can't be rewound.
   }
 
+  /**
+   * {@inheritdoc}
+   */
   public function next() {
     // Do nothing, since this is an always-empty implementation.
   }
 
+  /**
+   * {@inheritdoc}
+   */
   public function valid() {
     return FALSE;
   }
+
 }

core/lib/Drupal/Core/Database/StatementInterface.php

@@ -10,11 +10,6 @@ namespace Drupal\Core\Database;
 /**
  * Represents a prepared statement.
  *
- * Some methods in that class are purposefully commented out. Due to a change in
- * how PHP defines PDOStatement, we can't define a signature for those methods
- * that will work the same way between versions older than 5.2.6 and later
- * versions.  See http://bugs.php.net/bug.php?id=42452 for more details.
- *
  * Child implementations should either extend PDOStatement:
  * @code
  * class Drupal\Core\Database\Driver\oracle\Statement extends PDOStatement implements Drupal\Core\Database\StatementInterface {}
@@ -100,7 +95,7 @@ interface StatementInterface extends \Traversable {
    *   If $mode is PDO::FETCH_CLASS, the optional arguments to pass to the
    *   constructor.
    */
-  // public function setFetchMode($mode, $a1 = NULL, $a2 = array());
+   public function setFetchMode($mode, $a1 = NULL, $a2 = array());
 
   /**
    * Fetches the next row from a result set.
@@ -119,7 +114,7 @@ interface StatementInterface extends \Traversable {
    * @return
    *   A result, formatted according to $mode.
    */
-  // public function fetch($mode = NULL, $cursor_orientation = NULL, $cursor_offset = NULL);
+   public function fetch($mode = NULL, $cursor_orientation = NULL, $cursor_offset = NULL);
 
   /**
    * Returns a single field from the next record of a result set.
@@ -138,7 +133,7 @@ interface StatementInterface extends \Traversable {
    * The object will be of the class specified by StatementInterface::setFetchMode()
    * or stdClass if not specified.
    */
-  // public function fetchObject();
+   public function fetchObject();
 
   /**
    * Fetches the next row and returns it as an associative array.
@@ -165,7 +160,7 @@ interface StatementInterface extends \Traversable {
    * @return
    *   An array of results.
    */
-  // function fetchAll($mode = NULL, $column_index = NULL, array $constructor_arguments);
+   function fetchAll($mode = NULL, $column_index = NULL, $constructor_arguments = NULL);
 
   /**
    * Returns an entire single column of a result set as an indexed array.

core/lib/Drupal/Core/Database/StatementPrefetch.php

@@ -139,14 +139,7 @@ class StatementPrefetch implements \Iterator, StatementInterface {
   }
 
   /**
-   * Executes a prepared statement.
-   *
-   * @param $args
-   *   An array of values with as many elements as there are bound parameters in the SQL statement being executed.
-   * @param $options
-   *   An array of options for this query.
-   * @return
-   *   TRUE on success, or FALSE on failure.
+   * {@inheritdoc}
    */
   public function execute($args = array(), $options = array()) {
     if (isset($options['fetch'])) {
@@ -236,29 +229,29 @@ class StatementPrefetch implements \Iterator, StatementInterface {
   }
 
   /**
-   * Return the object's SQL query string.
+   * {@inheritdoc}
    */
   public function getQueryString() {
     return $this->queryString;
   }
 
   /**
-   * @see \PDOStatement::setFetchMode()
+   * {@inheritdoc}
    */
-  public function setFetchMode($fetchStyle, $a2 = NULL, $a3 = NULL) {
-    $this->defaultFetchStyle = $fetchStyle;
-    switch ($fetchStyle) {
+  public function setFetchMode($mode, $a1 = NULL, $a2 = array()) {
+    $this->defaultFetchStyle = $mode;
+    switch ($mode) {
       case \PDO::FETCH_CLASS:
-        $this->defaultFetchOptions['class'] = $a2;
-        if ($a3) {
-          $this->defaultFetchOptions['constructor_args'] = $a3;
+        $this->defaultFetchOptions['class'] = $a1;
+        if ($a2) {
+          $this->defaultFetchOptions['constructor_args'] = $a2;
         }
         break;
       case \PDO::FETCH_COLUMN:
-        $this->defaultFetchOptions['column'] = $a2;
+        $this->defaultFetchOptions['column'] = $a1;
         break;
       case \PDO::FETCH_INTO:
-        $this->defaultFetchOptions['object'] = $a2;
+        $this->defaultFetchOptions['object'] = $a1;
         break;
     }
 
@@ -274,8 +267,8 @@ class StatementPrefetch implements \Iterator, StatementInterface {
    * array position in $this->data and format it according to $this->fetchStyle
    * and $this->fetchMode.
    *
-   * @return
-   *  The current row formatted as requested.
+   * @return mixed
+   *   The current row formatted as requested.
    */
   public function current() {
     if (isset($this->currentRow)) {
@@ -327,16 +320,23 @@ class StatementPrefetch implements \Iterator, StatementInterface {
     }
   }
 
-  /* Implementations of Iterator. */
-
+  /**
+   * {@inheritdoc}
+   */
   public function key() {
     return $this->currentKey;
   }
 
+  /**
+   * {@inheritdoc}
+   */
   public function rewind() {
     // Nothing to do: our DatabaseStatement can't be rewound.
   }
 
+  /**
+   * {@inheritdoc}
+   */
   public function next() {
     if (!empty($this->data)) {
       $this->currentRow = reset($this->data);
@@ -348,6 +348,9 @@ class StatementPrefetch implements \Iterator, StatementInterface {
     }
   }
 
+  /**
+   * {@inheritdoc}
+   */
   public function valid() {
     return isset($this->currentRow);
   }
@@ -365,6 +368,9 @@ class StatementPrefetch implements \Iterator, StatementInterface {
     }
   }
 
+  /**
+   * {@inheritdoc}
+   */
   public function fetch($fetch_style = NULL, $cursor_orientation = \PDO::FETCH_ORI_NEXT, $cursor_offset = NULL) {
     if (isset($this->currentRow)) {
       // Set the fetch parameter.
@@ -398,10 +404,16 @@ class StatementPrefetch implements \Iterator, StatementInterface {
     }
   }
 
+  /**
+   * {@inheritdoc}
+   */
   public function fetchField($index = 0) {
     return $this->fetchColumn($index);
   }
 
+  /**
+   * {@inheritdoc}
+   */
   public function fetchObject($class_name = NULL, $constructor_args = array()) {
     if (isset($this->currentRow)) {
       if (!isset($class_name)) {
@@ -427,6 +439,9 @@ class StatementPrefetch implements \Iterator, StatementInterface {
     }
   }
 
+  /**
+   * {@inheritdoc}
+   */
   public function fetchAssoc() {
     if (isset($this->currentRow)) {
       $result = $this->currentRow;
@@ -438,14 +453,17 @@ class StatementPrefetch implements \Iterator, StatementInterface {
     }
   }
 
-  public function fetchAll($fetch_style = NULL, $fetch_column = NULL, $constructor_args = NULL) {
-    $this->fetchStyle = isset($fetch_style) ? $fetch_style : $this->defaultFetchStyle;
+  /**
+   * {@inheritdoc}
+   */
+  public function fetchAll($mode = NULL, $column_index = NULL, $constructor_arguments = NULL) {
+    $this->fetchStyle = isset($mode) ? $mode : $this->defaultFetchStyle;
     $this->fetchOptions = $this->defaultFetchOptions;
-    if (isset($fetch_column)) {
-      $this->fetchOptions['column'] = $fetch_column;
+    if (isset($column_index)) {
+      $this->fetchOptions['column'] = $column_index;
     }
-    if (isset($constructor_args)) {
-      $this->fetchOptions['constructor_args'] = $constructor_args;
+    if (isset($constructor_arguments)) {
+      $this->fetchOptions['constructor_args'] = $constructor_arguments;
     }
 
     $result = array();
@@ -462,6 +480,9 @@ class StatementPrefetch implements \Iterator, StatementInterface {
     return $result;
   }
 
+  /**
+   * {@inheritdoc}
+   */
   public function fetchCol($index = 0) {
     if (isset($this->columnNames[$index])) {
       $result = array();
@@ -477,6 +498,9 @@ class StatementPrefetch implements \Iterator, StatementInterface {
     }
   }
 
+  /**
+   * {@inheritdoc}
+   */
   public function fetchAllKeyed($key_index = 0, $value_index = 1) {
     if (!isset($this->columnNames[$key_index]) || !isset($this->columnNames[$value_index]))
       return array();
@@ -493,6 +517,9 @@ class StatementPrefetch implements \Iterator, StatementInterface {
     return $result;
   }
 
+  /**
+   * {@inheritdoc}
+   */
   public function fetchAllAssoc($key, $fetch_style = NULL) {
     $this->fetchStyle = isset($fetch_style) ? $fetch_style : $this->defaultFetchStyle;
     $this->fetchOptions = $this->defaultFetchOptions;

core/lib/Drupal/Core/Database/database.api.php

@@ -307,7 +307,8 @@
  *    specification). Each specification is an array containing the name of
  *    the referenced table ('table'), and an array of column mappings
  *    ('columns'). Column mappings are defined by key pairs ('source_column' =>
- *    'referenced_column').
+ *    'referenced_column'). This key is for documentation purposes only; foreign
+ *    keys are not created in the database, nor are they enforced by Drupal.
  *  - 'indexes':  An associative array of indexes ('indexname' =>
  *    specification). Each specification is an array of one or more
  *    key column specifiers (see below) that form an index on the
@@ -357,6 +358,8 @@
  *   'unique keys' => array(
  *     'vid' => array('vid'),
  *   ),
+ *   // For documentation purposes only; foreign keys are not created in the
+ *   // database.
  *   'foreign keys' => array(
  *     'node_revision' => array(
  *       'table' => 'node_field_revision',
@@ -467,7 +470,9 @@ function hook_query_TAG_alter(Drupal\Core\Database\Query\AlterableInterface $que
  * creation and alteration of the supported database engines.
  *
  * See the Schema API Handbook at https://www.drupal.org/node/146843 for details
- * on schema definition structures.
+ * on schema definition structures. Note that foreign key definitions are for
+ * documentation purposes only; foreign keys are not created in the database,
+ * nor are they enforced by Drupal.
  *
  * @return array
  *   A schema definition structure array. For each element of the
@@ -517,6 +522,8 @@ function hook_schema() {
       'nid_vid' => array('nid', 'vid'),
       'vid'     => array('vid'),
     ),
+    // For documentation purposes only; foreign keys are not created in the
+    // database.
     'foreign keys' => array(
       'node_revision' => array(
         'table' => 'node_field_revision',

core/lib/Drupal/Core/Datetime/DateFormatter.php

@@ -204,6 +204,11 @@ class DateFormatter {
         $interval %= $value;
         $granularity--;
       }
+      elseif ($output) {
+        // Break if there was previous output but not any output at this level,
+        // to avoid skipping levels and getting output like "1 year 1 second".
+        break;
+      }
 
       if ($granularity == 0) {
         break;
@@ -373,15 +378,21 @@ class DateFormatter {
             // ourselves.
             $interval_output = '';
             $days = $interval->d;
-            if ($days >= 7) {
-              $weeks = floor($days / 7);
+            $weeks = floor($days / 7);
+            if ($weeks) {
               $interval_output .= $this->formatPlural($weeks, '1 week', '@count weeks', array(), array('langcode' => $options['langcode']));
               $days -= $weeks * 7;
               $granularity--;
             }
-            if ($granularity > 0 && $days > 0) {
+
+            if ((!$output || $weeks > 0) && $granularity > 0 && $days > 0) {
               $interval_output .= ($interval_output ? ' ' : '') . $this->formatPlural($days, '1 day', '@count days', array(), array('langcode' => $options['langcode']));
             }
+            else {
+              // If we did not output days, set the granularity to 0 so that we
+              // will not output hours and get things like "1 week 1 hour".
+              $granularity = 0;
+            }
             break;
 
           case 'h':
@@ -397,9 +408,14 @@ class DateFormatter {
             break;
 
         }
-        $output .= ($output ? ' ' : '') . $interval_output;
+        $output .= ($output && $interval_output ? ' ' : '') . $interval_output;
         $granularity--;
       }
+      elseif ($output) {
+        // Break if there was previous output but not any output at this level,
+        // to avoid skipping levels and getting output like "1 year 1 second".
+        break;
+      }
 
       if ($granularity <= 0) {
         break;

core/lib/Drupal/Core/Datetime/Element/Datelist.php

@@ -335,10 +335,10 @@ class Datelist extends DateElementBase {
   protected static function incrementRound(&$date, $increment) {
     // Round minutes and seconds, if necessary.
     if ($date instanceOf DrupalDateTime && $increment > 1) {
-      $day = intval(date_format($date, 'j'));
-      $hour = intval(date_format($date, 'H'));
-      $second = intval(round(intval(date_format($date, 's')) / $increment) * $increment);
-      $minute = intval(date_format($date, 'i'));
+      $day = intval($date->format('j'));
+      $hour = intval($date->format('H'));
+      $second = intval(round(intval($date->format('s')) / $increment) * $increment);
+      $minute = intval($date->format('i'));
       if ($second == 60) {
         $minute += 1;
         $second = 0;
@@ -348,12 +348,12 @@ class Datelist extends DateElementBase {
         $hour += 1;
         $minute = 0;
       }
-      date_time_set($date, $hour, $minute, $second);
+      $date->setTime($hour, $minute, $second);
       if ($hour == 24) {
         $day += 1;
-        $year = date_format($date, 'Y');
-        $month = date_format($date, 'n');
-        date_date_set($date, $year, $month, $day);
+        $year = $date->format('Y');
+        $month = $date->format('n');
+        $date->setDate($year, $month, $day);
       }
     }
     return $date;

core/lib/Drupal/Core/Datetime/Element/Datetime.php

@@ -268,6 +268,7 @@ class Datetime extends DateElementBase {
         '#required' => $element['#required'],
         '#size' => max(12, strlen($element['#value']['date'])),
         '#error_no_message' => TRUE,
+        '#date_date_format' => $element['#date_date_format'],
       );
 
       // Allows custom callbacks to alter the element.

core/lib/Drupal/Core/Datetime/Entity/DateFormat.php

@@ -41,14 +41,14 @@ class DateFormat extends ConfigEntityBase implements DateFormatInterface {
    *
    * @var string
    */
-  public $id;
+  protected $id;
 
   /**
    * The human-readable name of the date format entity.
    *
    * @var string
    */
-  public $label;
+  protected $label;
 
   /**
    * The date format pattern.
@@ -101,7 +101,7 @@ class DateFormat extends ConfigEntityBase implements DateFormatInterface {
   /**
    * {@inheritdoc}
    */
-  public function getCacheTags() {
+  public function getCacheTagsToInvalidate() {
     return ['rendered'];
   }
 

core/lib/Drupal/Core/DependencyInjection/Compiler/BackendCompilerPass.php

@@ -42,11 +42,25 @@ class BackendCompilerPass implements CompilerPassInterface {
    * {@inheritdoc}
    */
   public function process(ContainerBuilder $container) {
-    $default_backend = $container->hasParameter('default_backend') ? $container->getParameter('default_backend') : NULL;
-    // No default backend was configured, so continue as normal.
-    if (!isset($default_backend)) {
-      return;
+    if ($container->hasParameter('default_backend')) {
+      $default_backend = $container->getParameter('default_backend');
+      // Opt out from the default backend.
+      if (!$default_backend) {
+        return;
+      }
     }
+    else {
+      try {
+        $default_backend = $container->get('database')->driver();
+        $container->set('database', NULL);
+      }
+      catch (\Exception $e) {
+        // If Drupal is not installed or a test doesn't define database there
+        // is nothing to override.
+        return;
+      }
+    }
+
 
     foreach ($container->findTaggedServiceIds('backend_overridable') as $id => $attributes) {
       // If the service is already an alias it is not the original backend, so

core/lib/Drupal/Core/DependencyInjection/Compiler/ContextProvidersPass.php

@@ -0,0 +1,33 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\Core\DependencyInjection\Compiler\ContextProvidersPass.
+ */
+
+namespace Drupal\Core\DependencyInjection\Compiler;
+
+use Symfony\Component\DependencyInjection\ContainerBuilder;
+use Symfony\Component\DependencyInjection\Compiler\CompilerPassInterface;
+
+/**
+ * Adds the context provider service IDs to the context manager.
+ */
+class ContextProvidersPass implements CompilerPassInterface {
+
+  /**
+   * {@inheritdoc}
+   *
+   * Passes the service IDs of all context providers to the context repository.
+   */
+  public function process(ContainerBuilder $container) {
+    $context_providers = [];
+    foreach (array_keys($container->findTaggedServiceIds('context_provider')) as $id) {
+      $context_providers[] = $id;
+    }
+
+    $definition = $container->getDefinition('context.repository');
+    $definition->addArgument($context_providers);
+  }
+
+}

core/lib/Drupal/Core/DependencyInjection/Compiler/GuzzleMiddlewarePass.php

@@ -0,0 +1,24 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\Core\DependencyInjection\Compiler\GuzzleMiddlewarePass.
+ */
+
+namespace Drupal\Core\DependencyInjection\Compiler;
+
+use Symfony\Component\DependencyInjection\Compiler\CompilerPassInterface;
+use Symfony\Component\DependencyInjection\ContainerBuilder;
+
+class GuzzleMiddlewarePass implements CompilerPassInterface {
+
+  /**
+   * {@inheritdoc}
+   */
+  public function process(ContainerBuilder $container) {
+    $middleware_ids = array_keys($container->findTaggedServiceIds('http_client_middleware'));
+    $container->getDefinition('http_handler_stack_configurator')
+      ->addArgument($middleware_ids);
+  }
+
+}

core/lib/Drupal/Core/DependencyInjection/Compiler/ProxyServicesPass.php

@@ -0,0 +1,74 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\Core\DependencyInjection\Compiler\ProxyServicesPass.
+ */
+
+namespace Drupal\Core\DependencyInjection\Compiler;
+
+use Drupal\Component\ProxyBuilder\ProxyBuilder;
+use Symfony\Component\DependencyInjection\Compiler\CompilerPassInterface;
+use Symfony\Component\DependencyInjection\ContainerBuilder;
+use Symfony\Component\DependencyInjection\Definition;
+use Symfony\Component\DependencyInjection\Exception\InvalidArgumentException;
+use Symfony\Component\DependencyInjection\Reference;
+
+/**
+ * Replaces all services with a lazy flag.
+ */
+class ProxyServicesPass implements CompilerPassInterface {
+
+  /**
+   * {@inheritdoc}
+   */
+  public function process(ContainerBuilder $container) {
+    foreach ($container->getDefinitions() as $service_id => $definition) {
+      if ($definition->isLazy()) {
+        $proxy_class = ProxyBuilder::buildProxyClassName($definition->getClass());
+        if (class_exists($proxy_class)) {
+          // Copy the existing definition to a new entry.
+          $definition->setLazy(FALSE);
+          // Ensure that the service is accessible.
+          $definition->setPublic(TRUE);
+          $new_service_id = 'drupal.proxy_original_service.' . $service_id;
+          $container->setDefinition($new_service_id, $definition);
+
+          $container->register($service_id, $proxy_class)
+            ->setArguments([new Reference('service_container'), $new_service_id]);
+        }
+        else {
+          $class_name = $definition->getClass();
+
+          // Find the root namespace.
+          $match = [];
+          preg_match('/([a-zA-Z0-9_]+\\\\[a-zA-Z0-9_]+)\\\\(.+)/', $class_name, $match);
+          $root_namespace = $match[1];
+
+          // Find the root namespace path.
+          $root_namespace_dir = '[namespace_root_path]';
+
+          $namespaces = $container->getParameter('container.namespaces');
+
+          // Hardcode Drupal Core, because it is not registered.
+          $namespaces['Drupal\Core'] = 'core/lib/Drupal/Core';
+
+          if (isset($namespaces[$root_namespace])) {
+            $root_namespace_dir = $namespaces[$root_namespace];
+          }
+
+          $message =<<<EOF
+
+Missing proxy class '$proxy_class' for lazy service '$service_id'.
+Use the following command to generate the proxy class:
+  php core/scripts/generate-proxy-class.php '$class_name' "$root_namespace_dir"
+
+
+EOF;
+          trigger_error($message, E_USER_WARNING);
+        }
+      }
+    }
+  }
+
+}

core/lib/Drupal/Core/DrupalKernel.php

@@ -8,7 +8,6 @@
 namespace Drupal\Core;
 
 use Drupal\Component\FileCache\FileCacheFactory;
-use Drupal\Component\ProxyBuilder\ProxyDumper;
 use Drupal\Component\Utility\Crypt;
 use Drupal\Component\Utility\Unicode;
 use Drupal\Component\Utility\UrlHelper;
@@ -24,7 +23,6 @@ use Drupal\Core\Http\TrustedHostsRequestFactory;
 use Drupal\Core\Language\Language;
 use Drupal\Core\PageCache\RequestPolicyInterface;
 use Drupal\Core\PhpStorage\PhpStorageFactory;
-use Drupal\Core\ProxyBuilder\ProxyBuilder;
 use Drupal\Core\Site\Settings;
 use Symfony\Cmf\Component\Routing\RouteObjectInterface;
 use Symfony\Component\DependencyInjection\ContainerInterface;
@@ -54,8 +52,6 @@ use Symfony\Component\Routing\Route;
  */
 class DrupalKernel implements DrupalKernelInterface, TerminableInterface {
 
-  const CONTAINER_BASE_CLASS = '\Drupal\Core\DependencyInjection\Container';
-
   /**
    * Holds the container instance.
    *
@@ -128,6 +124,13 @@ class DrupalKernel implements DrupalKernelInterface, TerminableInterface {
    */
   protected $allowDumping;
 
+  /**
+   * Whether the container needs to be rebuilt the next time it is initialized.
+   *
+   * @var bool
+   */
+  protected $containerNeedsRebuild = FALSE;
+
   /**
    * Whether the container needs to be dumped once booting is complete.
    *
@@ -463,8 +466,8 @@ class DrupalKernel implements DrupalKernelInterface, TerminableInterface {
     $this->container->get('request_stack')->push($request);
 
     // Set the allowed protocols once we have the config available.
-    $allowed_protocols = $this->container->get('config.factory')->get('system.filter')->get('protocols');
-    if (!isset($allowed_protocols)) {
+    $allowed_protocols = $this->container->getParameter('filter_protocols');
+    if (!$allowed_protocols) {
       // \Drupal\Component\Utility\UrlHelper::filterBadProtocol() is called by
       // the installer and update.php, in which case the configuration may not
       // exist (yet). Provide a minimal default set of allowed protocols for
@@ -697,11 +700,13 @@ class DrupalKernel implements DrupalKernelInterface, TerminableInterface {
     }
 
     // If we haven't yet booted, we don't need to do anything: the new module
-    // list will take effect when boot() is called. If we have already booted,
-    // then rebuild the container in order to refresh the serviceProvider list
-    // and container.
+    // list will take effect when boot() is called. However we set a
+    // flag that the container needs a rebuild, so that a potentially cached
+    // container is not used. If we have already booted, then rebuild the
+    // container in order to refresh the serviceProvider list and container.
+    $this->containerNeedsRebuild = TRUE;
     if ($this->booted) {
-      $this->initializeContainer(TRUE);
+      $this->initializeContainer();
     }
   }
 
@@ -740,11 +745,9 @@ class DrupalKernel implements DrupalKernelInterface, TerminableInterface {
   /**
    * Initializes the service container.
    *
-   * @param bool $rebuild
-   *   Force a container rebuild.
    * @return \Symfony\Component\DependencyInjection\ContainerInterface
    */
-  protected function initializeContainer($rebuild = FALSE) {
+  protected function initializeContainer() {
     $this->containerNeedsDumping = FALSE;
     $session_started = FALSE;
     if (isset($this->container)) {
@@ -766,7 +769,7 @@ class DrupalKernel implements DrupalKernelInterface, TerminableInterface {
 
     // If the module list hasn't already been set in updateModules and we are
     // not forcing a rebuild, then try and load the container from the disk.
-    if (empty($this->moduleList) && !$rebuild) {
+    if (empty($this->moduleList) && !$this->containerNeedsRebuild) {
       $fully_qualified_class_name = '\\' . $this->getClassNamespace() . '\\' . $this->getClassName();
 
       // First, try to load from storage.
@@ -783,6 +786,9 @@ class DrupalKernel implements DrupalKernelInterface, TerminableInterface {
       $container = $this->compileContainer();
     }
 
+    // The container was rebuilt successfully.
+    $this->containerNeedsRebuild = FALSE;
+
     $this->attachSynthetic($container);
 
     $this->container = $container;
@@ -807,7 +813,8 @@ class DrupalKernel implements DrupalKernelInterface, TerminableInterface {
     \Drupal::setContainer($this->container);
 
     // If needs dumping flag was set, dump the container.
-    if ($this->containerNeedsDumping && !$this->dumpDrupalContainer($this->container, static::CONTAINER_BASE_CLASS)) {
+    $base_class = Settings::get('container_base_class', '\Drupal\Core\DependencyInjection\Container');
+    if ($this->containerNeedsDumping && !$this->dumpDrupalContainer($this->container, $base_class)) {
       $this->container->get('logger.factory')->get('DrupalKernel')->notice('Container cannot be written to disk');
     }
 
@@ -1000,15 +1007,33 @@ class DrupalKernel implements DrupalKernelInterface, TerminableInterface {
   }
 
   /**
-   * Force a container rebuild.
-   *
-   * @return \Symfony\Component\DependencyInjection\ContainerInterface
+   * {@inheritdoc}
    */
   public function rebuildContainer() {
     // Empty module properties and for them to be reloaded from scratch.
     $this->moduleList = NULL;
     $this->moduleData = array();
-    return $this->initializeContainer(TRUE);
+    $this->containerNeedsRebuild = TRUE;
+    return $this->initializeContainer();
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function invalidateContainer() {
+    // An invalidated container needs a rebuild.
+    $this->containerNeedsRebuild = TRUE;
+
+    // If we have not yet booted, settings or bootstrap services might not yet
+    // be available. In that case the container will not be loaded from cache
+    // due to the above setting when the Kernel is booted.
+    if (!$this->booted) {
+      return;
+    }
+
+    // Also wipe the PHP Storage caches, so that the container is rebuilt
+    // for the next request.
+    $this->storage()->deleteAll();
   }
 
   /**
@@ -1180,7 +1205,6 @@ class DrupalKernel implements DrupalKernelInterface, TerminableInterface {
     }
     // Cache the container.
     $dumper = new PhpDumper($container);
-    $dumper->setProxyDumper(new ProxyDumper(new ProxyBuilder()));
     $class = $this->getClassName();
     $namespace = $this->getClassNamespace();
     $content = $dumper->dump([
@@ -1336,8 +1360,6 @@ class DrupalKernel implements DrupalKernelInterface, TerminableInterface {
    *
    * @return bool
    *   TRUE if the hostmame is valid, or FALSE otherwise.
-   *
-   * @todo Adjust per resolution to https://github.com/symfony/symfony/issues/12349
    */
   public static function validateHostname(Request $request) {
     // $request->getHost() can throw an UnexpectedValueException if it
@@ -1380,7 +1402,7 @@ class DrupalKernel implements DrupalKernelInterface, TerminableInterface {
    * @param array $host_patterns
    *   The array of trusted host patterns.
    *
-   * @return boolean
+   * @return bool
    *   TRUE if the Host header is trusted, FALSE otherwise.
    *
    * @see https://www.drupal.org/node/1992030

core/lib/Drupal/Core/DrupalKernelInterface.php

@@ -96,6 +96,18 @@ interface DrupalKernelInterface extends HttpKernelInterface {
    */
   public function updateModules(array $module_list, array $module_filenames = array());
 
+  /**
+   * Force a container rebuild.
+   *
+   * @return \Symfony\Component\DependencyInjection\ContainerInterface
+   */
+  public function rebuildContainer();
+
+  /**
+   * Invalidate the service container for the next request.
+   */
+  public function invalidateContainer();
+
   /**
    * Prepare the kernel for handling a request without handling the request.
    *

core/lib/Drupal/Core/Entity/ContentEntityBase.php

@@ -138,12 +138,33 @@ abstract class ContentEntityBase extends Entity implements \IteratorAggregate, C
   protected $isDefaultRevision = TRUE;
 
   /**
-   * Holds entity keys like the ID, bundle and revision ID.
+   * Holds translatable entity keys such as the ID, bundle and revision ID.
    *
    * @var array
    */
   protected $entityKeys = array();
 
+  /**
+   * Holds translatable entity keys such as the label.
+   *
+   * @var array
+   */
+  protected $translatableEntityKeys = array();
+
+  /**
+   * Whether entity validation was performed.
+   *
+   * @var bool
+   */
+  protected $validated = FALSE;
+
+  /**
+   * Whether entity validation is required before saving the entity.
+   *
+   * @var bool
+   */
+  protected $validationRequired = FALSE;
+
   /**
    * Overrides Entity::__construct().
    */
@@ -165,14 +186,36 @@ abstract class ContentEntityBase extends Entity implements \IteratorAggregate, C
     $this->values = $values;
     foreach ($this->getEntityType()->getKeys() as $key => $field_name) {
       if (isset($this->values[$field_name])) {
-        if (is_array($this->values[$field_name]) && isset($this->values[$field_name][LanguageInterface::LANGCODE_DEFAULT])) {
-          if (is_array($this->values[$field_name][LanguageInterface::LANGCODE_DEFAULT])) {
-            if (isset($this->values[$field_name][LanguageInterface::LANGCODE_DEFAULT][0]['value'])) {
-              $this->entityKeys[$key] = $this->values[$field_name][LanguageInterface::LANGCODE_DEFAULT][0]['value'];
+        if (is_array($this->values[$field_name])) {
+          // We store untranslatable fields into an entity key without using a
+          // langcode key.
+          if (!$this->getFieldDefinition($field_name)->isTranslatable()) {
+            if (isset($this->values[$field_name][LanguageInterface::LANGCODE_DEFAULT])) {
+              if (is_array($this->values[$field_name][LanguageInterface::LANGCODE_DEFAULT])) {
+                if (isset($this->values[$field_name][LanguageInterface::LANGCODE_DEFAULT][0]['value'])) {
+                  $this->entityKeys[$key] = $this->values[$field_name][LanguageInterface::LANGCODE_DEFAULT][0]['value'];
+                }
+              }
+              else {
+                $this->entityKeys[$key] = $this->values[$field_name][LanguageInterface::LANGCODE_DEFAULT];
+              }
             }
           }
           else {
-            $this->entityKeys[$key] = $this->values[$field_name][LanguageInterface::LANGCODE_DEFAULT];
+            // We save translatable fields such as the publishing status of a node
+            // into an entity key array keyed by langcode as a performance
+            // optimization, so we don't have to go through TypedData when we
+            // need these values.
+            foreach ($this->values[$field_name] as $langcode => $field_value) {
+              if (is_array($this->values[$field_name][$langcode])) {
+                if (isset($this->values[$field_name][$langcode][0]['value'])) {
+                  $this->translatableEntityKeys[$key][$langcode] = $this->values[$field_name][$langcode][0]['value'];
+                }
+              }
+              else {
+                $this->translatableEntityKeys[$key][$langcode] = $this->values[$field_name][$langcode];
+              }
+            }
           }
         }
       }
@@ -220,7 +263,7 @@ abstract class ContentEntityBase extends Entity implements \IteratorAggregate, C
    */
   public function setNewRevision($value = TRUE) {
     if (!$this->getEntityType()->hasKey('revision')) {
-      throw new \LogicException(SafeMarkup::format('Entity type @entity_type does not support revisions.', ['@entity_type' => $this->getEntityTypeId()]));
+      throw new \LogicException("Entity type {$this->getEntityTypeId()} does not support revisions.");
     }
 
     if ($value && !$this->newRevision) {
@@ -302,6 +345,23 @@ abstract class ContentEntityBase extends Entity implements \IteratorAggregate, C
     return !empty($bundles[$this->bundle()]['translatable']) && !$this->getUntranslated()->language()->isLocked() && $this->languageManager()->isMultilingual();
   }
 
+  /**
+   * {@inheritdoc}
+   */
+  public function preSave(EntityStorageInterface $storage) {
+    // An entity requiring validation should not be saved if it has not been
+    // actually validated.
+    if ($this->validationRequired && !$this->validated) {
+      // @todo Make this an assertion in https://www.drupal.org/node/2408013.
+      throw new \LogicException('Entity validation was skipped.');
+    }
+    else {
+      $this->validated = FALSE;
+    }
+
+    parent::preSave($storage);
+  }
+
   /**
    * {@inheritdoc}
    */
@@ -312,10 +372,26 @@ abstract class ContentEntityBase extends Entity implements \IteratorAggregate, C
    * {@inheritdoc}
    */
   public function validate() {
+    $this->validated = TRUE;
     $violations = $this->getTypedData()->validate();
     return new EntityConstraintViolationList($this, iterator_to_array($violations));
   }
 
+  /**
+   * {@inheritdoc}
+   */
+  public function isValidationRequired() {
+    return (bool) $this->validationRequired;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function setValidationRequired($required) {
+    $this->validationRequired = $required;
+    return $this;
+  }
+
   /**
    * Clear entity translation object cache to remove stale references.
    */
@@ -388,15 +464,14 @@ abstract class ContentEntityBase extends Entity implements \IteratorAggregate, C
    */
   protected function getTranslatedField($name, $langcode) {
     if ($this->translations[$this->activeLangcode]['status'] == static::TRANSLATION_REMOVED) {
-      $message = 'The entity object refers to a removed translation (@langcode) and cannot be manipulated.';
-      throw new \InvalidArgumentException(SafeMarkup::format($message, array('@langcode' => $this->activeLangcode)));
+      throw new \InvalidArgumentException("The entity object refers to a removed translation ({$this->activeLangcode}) and cannot be manipulated.");
     }
     // Populate $this->fields to speed-up further look-ups and to keep track of
     // fields objects, possibly holding changes to field values.
     if (!isset($this->fields[$name][$langcode])) {
       $definition = $this->getFieldDefinition($name);
       if (!$definition) {
-        throw new \InvalidArgumentException('Field ' . SafeMarkup::checkPlain($name) . ' is unknown.');
+        throw new \InvalidArgumentException("Field $name is unknown.");
       }
       // Non-translatable fields are always stored with
       // LanguageInterface::LANGCODE_DEFAULT as key.
@@ -413,7 +488,7 @@ abstract class ContentEntityBase extends Entity implements \IteratorAggregate, C
         if (isset($this->values[$name][$langcode])) {
           $value = $this->values[$name][$langcode];
         }
-        $field = \Drupal::service('plugin.manager.field.field_type')->createFieldItemList($this, $name, $value);
+        $field = \Drupal::service('plugin.manager.field.field_type')->createFieldItemList($this->getTranslation($langcode), $name, $value);
         if ($default) {
           // $this->defaultLangcode might not be set if we are initializing the
           // default language code cache, in which case there is no valid
@@ -454,6 +529,19 @@ abstract class ContentEntityBase extends Entity implements \IteratorAggregate, C
     return $fields;
   }
 
+  /**
+   * {@inheritdoc}
+   */
+  public function getTranslatableFields($include_computed = TRUE) {
+    $fields = [];
+    foreach ($this->getFieldDefinitions() as $name => $definition) {
+      if (($include_computed || !$definition->isComputed()) && $definition->isTranslatable()) {
+        $fields[$name] = $this->get($name);
+      }
+    }
+    return $fields;
+  }
+
   /**
    * {@inheritdoc}
    */
@@ -537,12 +625,12 @@ abstract class ContentEntityBase extends Entity implements \IteratorAggregate, C
     // Get the language code if the property exists.
     // Try to read the value directly from the list of entity keys which got
     // initialized in __construct(). This avoids creating a field item object.
-    if (isset($this->entityKeys['langcode'])) {
-      $this->defaultLangcode = $this->entityKeys['langcode'];
+    if (isset($this->translatableEntityKeys['langcode'][$this->activeLangcode])) {
+      $this->defaultLangcode = $this->translatableEntityKeys['langcode'][$this->activeLangcode];
     }
     elseif ($this->hasField($this->langcodeKey) && ($item = $this->get($this->langcodeKey)) && isset($item->language)) {
       $this->defaultLangcode = $item->language->getId();
-      $this->entityKeys['langcode'] = $this->defaultLangcode;
+      $this->translatableEntityKeys['langcode'][$this->activeLangcode] = $this->defaultLangcode;
     }
 
     if (empty($this->defaultLangcode)) {
@@ -583,8 +671,13 @@ abstract class ContentEntityBase extends Entity implements \IteratorAggregate, C
     // that check, as it ready only and must not change, unsetting it could
     // lead to recursions.
     if ($key = array_search($name, $this->getEntityType()->getKeys())) {
-      if (isset($this->entityKeys[$key]) && $key != 'bundle') {
-        unset($this->entityKeys[$key]);
+      if ($key != 'bundle') {
+        if (isset($this->entityKeys[$key])) {
+          unset($this->entityKeys[$key]);
+        }
+        elseif (isset($this->translatableEntityKeys[$key][$this->activeLangcode])) {
+          unset($this->translatableEntityKeys[$key][$this->activeLangcode]);
+        }
       }
     }
 
@@ -663,8 +756,7 @@ abstract class ContentEntityBase extends Entity implements \IteratorAggregate, C
     }
 
     if (empty($translation)) {
-      $message = 'Invalid translation language (@langcode) specified.';
-      throw new \InvalidArgumentException(SafeMarkup::format($message, array('@langcode' => $langcode)));
+      throw new \InvalidArgumentException("Invalid translation language ($langcode) specified.");
     }
 
     return $translation;
@@ -710,8 +802,6 @@ abstract class ContentEntityBase extends Entity implements \IteratorAggregate, C
     $translation->enforceIsNew = &$this->enforceIsNew;
     $translation->newRevision = &$this->newRevision;
     $translation->translationInitialize = FALSE;
-    // Reset language-dependent properties.
-    unset($translation->entityKeys['label']);
     $translation->typedData = NULL;
 
     return $translation;
@@ -733,8 +823,7 @@ abstract class ContentEntityBase extends Entity implements \IteratorAggregate, C
   public function addTranslation($langcode, array $values = array()) {
     $this->getLanguages();
     if (!isset($this->languages[$langcode]) || $this->hasTranslation($langcode)) {
-      $message = 'Invalid translation language (@langcode) specified.';
-      throw new \InvalidArgumentException(SafeMarkup::format($message, array('@langcode' => $langcode)));
+      throw new \InvalidArgumentException("Invalid translation language ($langcode) specified.");
     }
 
     // Instantiate a new empty entity so default values will be populated in the
@@ -784,8 +873,7 @@ abstract class ContentEntityBase extends Entity implements \IteratorAggregate, C
       $this->translations[$langcode]['status'] = static::TRANSLATION_REMOVED;
     }
     else {
-      $message = 'The specified translation (@langcode) cannot be removed.';
-      throw new \InvalidArgumentException(SafeMarkup::format($message, array('@langcode' => $langcode)));
+      throw new \InvalidArgumentException("The specified translation ($langcode) cannot be removed.");
     }
   }
 
@@ -918,8 +1006,7 @@ abstract class ContentEntityBase extends Entity implements \IteratorAggregate, C
    */
   public function createDuplicate() {
     if ($this->translations[$this->activeLangcode]['status'] == static::TRANSLATION_REMOVED) {
-      $message = 'The entity object refers to a removed translation (@langcode) and cannot be manipulated.';
-      throw new \InvalidArgumentException(SafeMarkup::format($message, array('@langcode' => $this->activeLangcode)));
+      throw new \InvalidArgumentException("The entity object refers to a removed translation ({$this->activeLangcode}) and cannot be manipulated.");
     }
 
     $duplicate = clone $this;
@@ -962,7 +1049,7 @@ abstract class ContentEntityBase extends Entity implements \IteratorAggregate, C
         }
         foreach ($values as $langcode => $items) {
           $this->fields[$name][$langcode] = clone $items;
-          $this->fields[$name][$langcode]->setContext($name, $this->getTypedData());
+          $this->fields[$name][$langcode]->setContext($name, $this->getTranslation($langcode)->getTypedData());
         }
       }
 
@@ -1020,18 +1107,34 @@ abstract class ContentEntityBase extends Entity implements \IteratorAggregate, C
    *   The value of the entity key, NULL if not defined.
    */
   protected function getEntityKey($key) {
-    if (!isset($this->entityKeys[$key]) || !array_key_exists($key, $this->entityKeys)) {
-      if ($this->getEntityType()->hasKey($key)) {
-        $field_name = $this->getEntityType()->getKey($key);
-        $property = $this->getFieldDefinition($field_name)->getFieldStorageDefinition()->getMainPropertyName();
-        $this->entityKeys[$key] = $this->get($field_name)->$property;
+    // If the value is known already, return it.
+    if (isset($this->entityKeys[$key])) {
+      return $this->entityKeys[$key];
+    }
+    if (isset($this->translatableEntityKeys[$key][$this->activeLangcode])) {
+      return $this->translatableEntityKeys[$key][$this->activeLangcode];
+    }
+
+    // Otherwise fetch the value by creating a field object.
+    $value = NULL;
+    if ($this->getEntityType()->hasKey($key)) {
+      $field_name = $this->getEntityType()->getKey($key);
+      $definition = $this->getFieldDefinition($field_name);
+      $property = $definition->getFieldStorageDefinition()->getMainPropertyName();
+      $value = $this->get($field_name)->$property;
+
+      // Put it in the right array, depending on whether it is translatable.
+      if ($definition->isTranslatable()) {
+        $this->translatableEntityKeys[$key][$this->activeLangcode] = $value;
       }
       else {
-        $this->entityKeys[$key] = NULL;
+        $this->entityKeys[$key] = $value;
       }
-
     }
-    return $this->entityKeys[$key];
+    else {
+      $this->entityKeys[$key] = $value;
+    }
+    return $value;
   }
 
   /**

core/lib/Drupal/Core/Entity/ContentEntityConfirmFormBase.php

@@ -86,9 +86,6 @@ abstract class ContentEntityConfirmFormBase extends ContentEntityForm implements
       'submit' => array(
         '#type' => 'submit',
         '#value' => $this->getConfirmText(),
-        '#validate' => array(
-          array($this, 'validate'),
-        ),
         '#submit' => array(
           array($this, 'submitForm'),
         ),
@@ -121,9 +118,10 @@ abstract class ContentEntityConfirmFormBase extends ContentEntityForm implements
   /**
    * {@inheritdoc}
    */
-  public function validate(array $form, FormStateInterface $form_state) {
+  public function validateForm(array &$form, FormStateInterface $form_state) {
     // Override the default validation implementation as it is not necessary
     // nor possible to validate an entity in a confirmation form.
+    return $this->entity;
   }
 
 }

core/lib/Drupal/Core/Entity/ContentEntityForm.php

@@ -64,17 +64,28 @@ class ContentEntityForm extends EntityForm implements ContentEntityFormInterface
 
   /**
    * {@inheritdoc}
-   *
-   * Note that extending classes should not override this method to add entity
-   * validation logic, but define further validation constraints using the
-   * entity validation API and/or provide a new validation constraint if
-   * necessary. This is the only way to ensure that the validation logic
-   * is correctly applied independently of form submissions; e.g., for REST
-   * requests.
-   * For more information about entity validation, see
-   * https://www.drupal.org/node/2015613.
    */
-  public function validate(array $form, FormStateInterface $form_state) {
+  public function buildEntity(array $form, FormStateInterface $form_state) {
+    /** @var \Drupal\Core\Entity\ContentEntityInterface $entity */
+    $entity = parent::buildEntity($form, $form_state);
+
+    // Mark the entity as requiring validation.
+    $entity->setValidationRequired(!$form_state->getTemporaryValue('entity_validated'));
+
+    return $entity;
+  }
+
+  /**
+   * {@inheritdoc}
+   *
+   * Button-level validation handlers are highly discouraged for entity forms,
+   * as they will prevent entity validation from running. If the entity is going
+   * to be saved during the form submission, this method should be manually
+   * invoked from the button-level validation handler, otherwise an exception
+   * will be thrown.
+   */
+  public function validateForm(array &$form, FormStateInterface $form_state) {
+    parent::validateForm($form, $form_state);
     /** @var \Drupal\Core\Entity\ContentEntityInterface $entity */
     $entity = $this->buildEntity($form, $form_state);
 
@@ -87,10 +98,10 @@ class ContentEntityForm extends EntityForm implements ContentEntityFormInterface
 
     $this->flagViolations($violations, $form, $form_state);
 
-    // @todo Remove this.
-    // Execute legacy global validation handlers.
-    $form_state->setValidateHandlers([]);
-    \Drupal::service('form_validator')->executeValidateHandlers($form, $form_state);
+    // The entity was validated.
+    $entity->setValidationRequired(FALSE);
+    $form_state->setTemporaryValue('entity_validated', TRUE);
+
     return $entity;
   }