Move into nested docroot

web/core/modules/block/block.api.php

@@ -0,0 +1,221 @@
+<?php
+
+/**
+ * @file
+ * Hooks provided by the Block module.
+ */
+
+use Drupal\Core\Access\AccessResult;
+
+/**
+ * @defgroup block_api Block API
+ * @{
+ * Information about the classes and interfaces that make up the Block API.
+ *
+ * Blocks are a combination of a configuration entity and a plugin. The
+ * configuration entity stores placement information (theme, region, weight) and
+ * any other configuration that is specific to the block. The block plugin does
+ * the work of rendering the block's content for display.
+ *
+ * To define a block in a module you need to:
+ * - Define a Block plugin by creating a new class that implements the
+ *   \Drupal\Core\Block\BlockPluginInterface, in namespace Plugin\Block under your
+ *   module namespace. For more information about creating plugins, see the
+ *   @link plugin_api Plugin API topic. @endlink
+ * - Usually you will want to extend the \Drupal\Core\Block\BlockBase class, which
+ *   provides a common configuration form and utility methods for getting and
+ *   setting configuration in the block configuration entity.
+ * - Block plugins use the annotations defined by
+ *   \Drupal\Core\Block\Annotation\Block. See the
+ *   @link annotation Annotations topic @endlink for more information about
+ *   annotations.
+ *
+ * The Block API also makes use of Condition plugins, for conditional block
+ * placement. Condition plugins have interface
+ * \Drupal\Core\Condition\ConditionInterface, base class
+ * \Drupal\Core\Condition\ConditionPluginBase, and go in plugin namespace
+ * Plugin\Condition. Again, see the Plugin API and Annotations topics for
+ * details of how to create a plugin class and annotate it.
+ *
+ * There are also several block-related hooks, which allow you to affect
+ * the content and access permissions for blocks:
+ * - hook_block_view_alter()
+ * - hook_block_view_BASE_BLOCK_ID_alter()
+ * - hook_block_access()
+ *
+ * Further information and examples:
+ * - \Drupal\system\Plugin\Block\SystemPoweredByBlock provides a simple example
+ *   of defining a block.
+ * - \Drupal\user\Plugin\Condition\UserRole is a straightforward example of a
+ *   block placement condition plugin.
+ * - \Drupal\book\Plugin\Block\BookNavigationBlock is an example of a block with
+ *   a custom configuration form.
+ * - For a more in-depth discussion of the Block API, see
+ *   https://www.drupal.org/developing/api/8/block_api.
+ * - The Examples for Developers project also provides a Block example in
+ *   https://www.drupal.org/project/examples.
+ * @}
+ */
+
+/**
+ * @addtogroup hooks
+ * @{
+ */
+
+/**
+ * Alter the result of \Drupal\Core\Block\BlockBase::build().
+ *
+ * This hook is called after the content has been assembled in a structured
+ * array and may be used for doing processing which requires that the complete
+ * block content structure has been built.
+ *
+ * If the module wishes to act on the rendered HTML of the block rather than
+ * the structured content array, it may use this hook to add a #post_render
+ * callback. Alternatively, it could also implement hook_preprocess_HOOK() for
+ * block.html.twig. See drupal_render() documentation or the
+ * @link themeable Default theme implementations topic @endlink for details.
+ *
+ * In addition to hook_block_view_alter(), which is called for all blocks, there
+ * is hook_block_view_BASE_BLOCK_ID_alter(), which can be used to target a
+ * specific block or set of similar blocks.
+ *
+ * @param array &$build
+ *   A renderable array of data, as returned from the build() implementation of
+ *   the plugin that defined the block:
+ *   - #title: The default localized title of the block.
+ * @param \Drupal\Core\Block\BlockPluginInterface $block
+ *   The block plugin instance.
+ *
+ * @see hook_block_view_BASE_BLOCK_ID_alter()
+ * @see entity_crud
+ *
+ * @ingroup block_api
+ */
+function hook_block_view_alter(array &$build, \Drupal\Core\Block\BlockPluginInterface $block) {
+  // Remove the contextual links on all blocks that provide them.
+  if (isset($build['#contextual_links'])) {
+    unset($build['#contextual_links']);
+  }
+}
+
+/**
+ * Provide a block plugin specific block_view alteration.
+ *
+ * In this hook name, BASE_BLOCK_ID refers to the block implementation's plugin
+ * id, regardless of whether the plugin supports derivatives. For example, for
+ * the \Drupal\system\Plugin\Block\SystemPoweredByBlock block, this would be
+ * 'system_powered_by_block' as per that class's annotation. And for the
+ * \Drupal\system\Plugin\Block\SystemMenuBlock block, it would be
+ * 'system_menu_block' as per that class's annotation, regardless of which menu
+ * the derived block is for.
+ *
+ * @param array $build
+ *   A renderable array of data, as returned from the build() implementation of
+ *   the plugin that defined the block:
+ *   - #title: The default localized title of the block.
+ * @param \Drupal\Core\Block\BlockPluginInterface $block
+ *   The block plugin instance.
+ *
+ * @see hook_block_view_alter()
+ * @see entity_crud
+ *
+ * @ingroup block_api
+ */
+function hook_block_view_BASE_BLOCK_ID_alter(array &$build, \Drupal\Core\Block\BlockPluginInterface $block) {
+  // Change the title of the specific block.
+  $build['#title'] = t('New title of the block');
+}
+
+/**
+ * Alter the result of \Drupal\Core\Block\BlockBase::build().
+ *
+ * Unlike hook_block_view_alter(), this hook is called very early, before the
+ * block is being assembled. Therefore, it is early enough to alter the
+ * cacheability metadata (change #cache), or to explicitly placeholder the block
+ * (set #create_placeholder).
+ *
+ * In addition to hook_block_build_alter(), which is called for all blocks,
+ * there is hook_block_build_BASE_BLOCK_ID_alter(), which can be used to target
+ * a specific block or set of similar blocks.
+ *
+ * @param array &$build
+ *   A renderable array of data, only containing #cache.
+ * @param \Drupal\Core\Block\BlockPluginInterface $block
+ *   The block plugin instance.
+ *
+ * @see hook_block_build_BASE_BLOCK_ID_alter()
+ * @see entity_crud
+ *
+ * @ingroup block_api
+ */
+function hook_block_build_alter(array &$build, \Drupal\Core\Block\BlockPluginInterface $block) {
+  // Add the 'user' cache context to some blocks.
+  if ($some_condition) {
+    $build['#cache']['contexts'][] = 'user';
+  }
+}
+
+/**
+ * Provide a block plugin specific block_build alteration.
+ *
+ * In this hook name, BASE_BLOCK_ID refers to the block implementation's plugin
+ * id, regardless of whether the plugin supports derivatives. For example, for
+ * the \Drupal\system\Plugin\Block\SystemPoweredByBlock block, this would be
+ * 'system_powered_by_block' as per that class's annotation. And for the
+ * \Drupal\system\Plugin\Block\SystemMenuBlock block, it would be
+ * 'system_menu_block' as per that class's annotation, regardless of which menu
+ * the derived block is for.
+ *
+ * @param array $build
+ *   A renderable array of data, only containing #cache.
+ * @param \Drupal\Core\Block\BlockPluginInterface $block
+ *   The block plugin instance.
+ *
+ * @see hook_block_build_alter()
+ * @see entity_crud
+ *
+ * @ingroup block_api
+ */
+function hook_block_build_BASE_BLOCK_ID_alter(array &$build, \Drupal\Core\Block\BlockPluginInterface $block) {
+  // Explicitly enable placeholdering of the specific block.
+  $build['#create_placeholder'] = TRUE;
+}
+
+/**
+ * Control access to a block instance.
+ *
+ * Modules may implement this hook if they want to have a say in whether or not
+ * a given user has access to perform a given operation on a block instance.
+ *
+ * @param \Drupal\block\Entity\Block $block
+ *   The block instance.
+ * @param string $operation
+ *   The operation to be performed; for instance, 'view', 'create', 'delete', or
+ *   'update'.
+ * @param \Drupal\Core\Session\AccountInterface $account
+ *   The user object to perform the access check operation on.
+ *
+ * @return \Drupal\Core\Access\AccessResultInterface
+ *   The access result. If all implementations of this hook return
+ *   AccessResultInterface objects whose value is !isAllowed() and
+ *   !isForbidden(), then default access rules from
+ *   \Drupal\block\BlockAccessControlHandler::checkAccess() are used.
+ *
+ * @see \Drupal\Core\Entity\EntityAccessControlHandler::access()
+ * @see \Drupal\block\BlockAccessControlHandler::checkAccess()
+ * @ingroup block_api
+ */
+function hook_block_access(\Drupal\block\Entity\Block $block, $operation, \Drupal\Core\Session\AccountInterface $account) {
+  // Example code that would prevent displaying the 'Powered by Drupal' block in
+  // a region different than the footer.
+  if ($operation == 'view' && $block->getPluginId() == 'system_powered_by_block') {
+    return AccessResult::forbiddenIf($block->getRegion() != 'footer')->addCacheableDependency($block);
+  }
+
+  // No opinion.
+  return AccessResult::neutral();
+}
+
+/**
+ * @} End of "addtogroup hooks".
+ */

web/core/modules/block/block.info.yml

@@ -0,0 +1,7 @@
+name: Block
+type: module
+description: 'Controls the visual building blocks a page is constructed with. Blocks are boxes of content rendered into an area, or region, of a web page.'
+package: Core
+version: VERSION
+core: 8.x
+configure: block.admin_display

web/core/modules/block/block.install

@@ -0,0 +1,128 @@
+<?php
+
+/**
+ * @file
+ * Contains install and update functions for Block.
+ */
+
+use Drupal\Core\Cache\Cache;
+
+/**
+ * Implements hook_install().
+ */
+function block_install() {
+  // Because the Block module upon installation unconditionally overrides all
+  // HTML output by selecting a different page display variant, we must
+  // invalidate all cached HTML output.
+  Cache::invalidateTags(['rendered']);
+}
+
+/**
+ * @addtogroup updates-8.0.0-beta
+ * @{
+ */
+
+/**
+ * Update block visibility context mapping.
+ */
+function block_update_8001() {
+  // This update function updates blocks for the change from
+  // https://www.drupal.org/node/2354889.
+
+  // Core visibility context plugins are updated automatically; blocks with
+  // unknown plugins are disabled and their previous visibility settings are
+  // saved in key value storage; see change record
+  // https://www.drupal.org/node/2527840 for more explanation.
+
+  // These are all the contexts that Drupal core provides.
+  $context_service_id_map = [
+    'node.node' => '@node.node_route_context:node',
+    'user.current_user' => '@user.current_user_context:current_user',
+  ];
+
+  foreach (array_keys(\Drupal::languageManager()->getDefinedLanguageTypesInfo()) as $language_type_id) {
+    $context_service_id_map['language.' . $language_type_id] = '@language.current_language_context:' . $language_type_id;
+  }
+
+  // Contributed modules should leverage hook_update_dependencies() in order to
+  // be executed after block_update_8001(). The blocks are then disabled if the
+  // contexts are still missing via
+  // block_post_update_disable_blocks_with_missing_contexts().
+  $config_factory = \Drupal::configFactory();
+  $backup_values = $update_backup = [];
+
+  foreach ($config_factory->listAll('block.block.') as $block_config_name) {
+    $block = $config_factory->getEditable($block_config_name);
+    if ($visibility = $block->get('visibility')) {
+      foreach ($visibility as $condition_plugin_id => &$condition) {
+        foreach ($condition['context_mapping'] as $key => $context) {
+          if (!isset($context_service_id_map[$context])) {
+            // Remove the visibility condition for unknown context mapping
+            // entries, so the update process itself runs through and users can
+            // fix their block placements manually OR alternatively contributed
+            // modules can run their own update functions to update mappings
+            // that they provide.
+            $backup_values[$context][] = $condition_plugin_id;
+            unset($visibility[$condition_plugin_id]);
+            continue;
+          }
+          // Replace the context ID based on the defined mapping.
+          $condition['context_mapping'][$key] = $context_service_id_map[$context];
+        }
+      }
+      $block->set('visibility', $visibility);
+
+      if ($backup_values) {
+        // We not only store the missing context mappings but also the previous
+        // block status, in order to allow contributed and custom modules to do
+        // their own updates.
+        $update_backup[$block->get('id')] = [
+          'missing_context_ids' => $backup_values,
+          'status' => $block->get('status')
+        ];
+      }
+    }
+
+    // Mark the resulting configuration as trusted data. This avoids issues with
+    // future schema changes.
+    $block->save(TRUE);
+  }
+
+  if ($update_backup) {
+    \Drupal::keyValue('update_backup')->set('block_update_8001', $update_backup);
+  }
+
+  return t('Block context IDs updated.');
+}
+
+/**
+ * Placeholder for the previous 8002 update.
+ */
+function block_update_8002() {
+  \Drupal::state()->set('block_update_8002_placeholder', TRUE);
+}
+
+/**
+ * Remove 'cache' setting.
+ */
+function block_update_8003() {
+  $config_factory = \Drupal::configFactory();
+  foreach ($config_factory->listAll('block.block.') as $block_config_name) {
+    $block = $config_factory->getEditable($block_config_name);
+
+    // Remove the 'cache' setting.
+    $settings = $block->get('settings');
+    unset($settings['cache']);
+    $block->set('settings', $settings);
+
+    // Mark the resulting configuration as trusted data. This avoids issues with
+    // future schema changes.
+    $block->save(TRUE);
+  }
+
+  return t('Block settings updated.');
+}
+
+/**
+ * @} End of "addtogroup updates-8.0.0-beta".
+ */

web/core/modules/block/block.libraries.yml

@@ -0,0 +1,19 @@
+drupal.block:
+  version: VERSION
+  js:
+    js/block.js: {}
+  dependencies:
+    - core/jquery
+    - core/drupal
+
+drupal.block.admin:
+  version: VERSION
+  js:
+    js/block.admin.js: {}
+  css:
+    theme:
+      css/block.admin.css: {}
+  dependencies:
+    - core/jquery
+    - core/drupal
+    - core/drupal.dialog.ajax

web/core/modules/block/block.links.contextual.yml

@@ -0,0 +1,4 @@
+block_configure:
+  title: 'Configure block'
+  route_name: 'entity.block.edit_form'
+  group: 'block'

web/core/modules/block/block.links.menu.yml

@@ -0,0 +1,5 @@
+block.admin_display:
+  title: 'Block layout'
+  parent: system.admin_structure
+  description: 'Configure what block content appears in your site''s sidebars and other regions.'
+  route_name: block.admin_display

web/core/modules/block/block.links.task.yml

@@ -0,0 +1,15 @@
+entity.block.edit_form:
+  title: 'Configure block'
+  route_name: entity.block.edit_form
+  base_route: entity.block.edit_form
+
+# Per theme block layout pages.
+block.admin_display:
+  title: 'Block layout'
+  route_name: block.admin_display
+  base_route: block.admin_display
+block.admin_display_theme:
+  title: 'Block layout'
+  route_name: block.admin_display_theme
+  parent_id: block.admin_display
+  deriver: 'Drupal\block\Plugin\Derivative\ThemeLocalTask'

web/core/modules/block/block.module

@@ -0,0 +1,286 @@
+<?php
+
+/**
+ * @file
+ * Controls the visual building blocks a page is constructed with.
+ */
+
+use Drupal\block\BlockInterface;
+use Drupal\Component\Utility\Html;
+use Drupal\Core\Routing\RouteMatchInterface;
+use Drupal\Core\Url;
+use Drupal\language\ConfigurableLanguageInterface;
+use Drupal\system\Entity\Menu;
+use Drupal\block\Entity\Block;
+
+/**
+ * Implements hook_help().
+ */
+function block_help($route_name, RouteMatchInterface $route_match) {
+  switch ($route_name) {
+    case 'help.page.block':
+      $block_content = \Drupal::moduleHandler()->moduleExists('block_content') ? \Drupal::url('help.page', array('name' => 'block_content')) : '#';
+      $output = '';
+      $output .= '<h3>' . t('About') . '</h3>';
+      $output .= '<p>' . t('The Block module allows you to place blocks in regions of your installed themes, and configure block settings. For more information, see the <a href=":blocks-documentation">online documentation for the Block module</a>.', array(':blocks-documentation' => 'https://www.drupal.org/documentation/modules/block/')) . '</p>';
+      $output .= '<h3>' . t('Uses') . '</h3>';
+      $output .= '<dl>';
+      $output .= '<dt>' . t('Placing and moving blocks') . '</dt>';
+      $output .= '<dd>' . t('You can place a new block in a region by selecting <em>Place block</em> on the <a href=":blocks">Block layout page</a>. Once a block is placed, it can be moved to a different region by drag-and-drop or by using the <em>Region</em> drop-down list, and then clicking <em>Save blocks</em>.', array(':blocks' => \Drupal::url('block.admin_display'))) . '</dd>';
+      $output .= '<dt>' . t('Toggling between different themes') . '</dt>';
+      $output .= '<dd>' . t('Blocks are placed and configured specifically for each theme. The Block layout page opens with the default theme, but you can toggle to other installed themes.') . '</dd>';
+      $output .= '<dt>' . t('Demonstrating block regions for a theme') . '</dt>';
+      $output .= '<dd>' . t('You can see where the regions are for the current theme by clicking the <em>Demonstrate block regions</em> link on the <a href=":blocks">Block layout page</a>. Regions are specific to each theme.', array(':blocks' => \Drupal::url('block.admin_display'))) . '</dd>';
+      $output .= '<dt>' . t('Configuring block settings') . '</dt>';
+      $output .= '<dd>' . t('To change the settings of an individual block click on the <em>Configure</em> link on the <a href=":blocks">Block layout page</a>. The available options vary depending on the module that provides the block. For all blocks you can change the block title and toggle whether to display it.', array(':blocks' => Drupal::url('block.admin_display'))) . '</dd>';
+      $output .= '<dt>' . t('Controlling visibility') . '</dt>';
+      $output .= '<dd>' . t('You can control the visibility of a block by restricting it to specific pages, content types, and/or roles by setting the appropriate options under <em>Visibility settings</em> of the block configuration.') . '</dd>';
+      $output .= '<dt>' . t('Adding custom blocks') . '</dt>';
+      $output .= '<dd>' . t('You can add custom blocks, if the <em>Custom Block</em> module is installed. For more information, see the <a href=":blockcontent-help">Custom Block help page</a>.', array(':blockcontent-help' => $block_content)) . '</dd>';
+      $output .= '</dl>';
+      return $output;
+  }
+  if ($route_name == 'block.admin_display' || $route_name == 'block.admin_display_theme') {
+    $demo_theme = $route_match->getParameter('theme') ?: \Drupal::config('system.theme')->get('default');
+    $themes = \Drupal::service('theme_handler')->listInfo();
+    $output = '<p>' . t('Block placement is specific to each theme on your site. Changes will not be saved until you click <em>Save blocks</em> at the bottom of the page.') . '</p>';
+    $output .= '<p>' . \Drupal::l(t('Demonstrate block regions (@theme)', array('@theme' => $themes[$demo_theme]->info['name'])), new Url('block.admin_demo', array('theme' => $demo_theme))) . '</p>';
+    return $output;
+  }
+}
+
+/**
+ * Implements hook_theme().
+ */
+function block_theme() {
+  return array(
+    'block' => array(
+      'render element' => 'elements',
+    ),
+  );
+}
+
+/**
+ * Implements hook_page_top().
+ */
+function block_page_top(array &$page_top) {
+  if (\Drupal::routeMatch()->getRouteName() === 'block.admin_demo') {
+    $theme = \Drupal::theme()->getActiveTheme()->getName();
+    $page_top['backlink'] = array(
+      '#type' => 'link',
+      '#title' => t('Exit block region demonstration'),
+      '#options' => array('attributes' => array('class' => array('block-demo-backlink'))),
+      '#weight' => -10,
+    );
+    if (\Drupal::config('system.theme')->get('default') == $theme) {
+      $page_top['backlink']['#url'] = Url::fromRoute('block.admin_display');
+    }
+    else {
+      $page_top['backlink']['#url'] = Url::fromRoute('block.admin_display_theme', ['theme' => $theme]);
+    }
+  }
+}
+
+/**
+ * Initializes blocks for installed themes.
+ *
+ * @param $theme_list
+ *   An array of theme names.
+ */
+function block_themes_installed($theme_list) {
+  foreach ($theme_list as $theme) {
+    // Don't initialize themes that are not displayed in the UI.
+    if (\Drupal::service('theme_handler')->hasUi($theme)) {
+      block_theme_initialize($theme);
+    }
+  }
+}
+
+/**
+ * Assigns an initial, default set of blocks for a theme.
+ *
+ * This function is called the first time a new theme is installed. The new
+ * theme gets a copy of the default theme's blocks, with the difference that if
+ * a particular region isn't available in the new theme, the block is assigned
+ * to the new theme's default region.
+ *
+ * @param $theme
+ *   The name of a theme.
+ */
+function block_theme_initialize($theme) {
+  // Initialize theme's blocks if none already registered.
+  $has_blocks = \Drupal::entityTypeManager()->getStorage('block')->loadByProperties(array('theme' => $theme));
+  if (!$has_blocks) {
+    $default_theme = \Drupal::config('system.theme')->get('default');
+    // Apply only to new theme's visible regions.
+    $regions = system_region_list($theme, REGIONS_VISIBLE);
+    $default_theme_blocks = \Drupal::entityTypeManager()->getStorage('block')->loadByProperties(array('theme' => $default_theme));
+    foreach ($default_theme_blocks as $default_theme_block_id => $default_theme_block) {
+      if (strpos($default_theme_block_id, $default_theme . '_') === 0) {
+        $id = str_replace($default_theme, $theme, $default_theme_block_id);
+      }
+      else {
+        $id = $theme . '_' . $default_theme_block_id;
+      }
+      $block = $default_theme_block->createDuplicateBlock($id, $theme);
+      // If the region isn't supported by the theme, assign the block to the
+      // theme's default region.
+      if (!isset($regions[$block->getRegion()])) {
+        $block->setRegion(system_default_region($theme));
+      }
+      $block->save();
+    }
+  }
+}
+
+/**
+ * Implements hook_rebuild().
+ */
+function block_rebuild() {
+  foreach (\Drupal::service('theme_handler')->listInfo() as $theme => $data) {
+    if ($data->status) {
+      $regions = system_region_list($theme);
+      /** @var \Drupal\block\BlockInterface[] $blocks */
+      $blocks = \Drupal::entityTypeManager()->getStorage('block')->loadByProperties(['theme' => $theme]);
+      foreach ($blocks as $block_id => $block) {
+        // Disable blocks in invalid regions.
+        $region = $block->getRegion();
+        if ($region !== BlockInterface::BLOCK_REGION_NONE) {
+          if (!empty($region) && !isset($regions[$region]) && $block->status()) {
+            drupal_set_message(t('The block %info was assigned to the invalid region %region and has been disabled.', ['%info' => $block_id, '%region' => $region]), 'warning');
+            $block->disable();
+          }
+          // Set region to none if not enabled.
+          if (!$block->status()) {
+            $block->setRegion(BlockInterface::BLOCK_REGION_NONE);
+            $block->save();
+          }
+        }
+      }
+    }
+  }
+}
+
+/**
+ * Implements hook_theme_suggestions_HOOK().
+ */
+function block_theme_suggestions_block(array $variables) {
+  $suggestions = array();
+
+  $suggestions[] = 'block__' . $variables['elements']['#configuration']['provider'];
+  // Hyphens (-) and underscores (_) play a special role in theme suggestions.
+  // Theme suggestions should only contain underscores, because within
+  // drupal_find_theme_templates(), underscores are converted to hyphens to
+  // match template file names, and then converted back to underscores to match
+  // pre-processing and other function names. So if your theme suggestion
+  // contains a hyphen, it will end up as an underscore after this conversion,
+  // and your function names won't be recognized. So, we need to convert
+  // hyphens to underscores in block deltas for the theme suggestions.
+
+  // We can safely explode on : because we know the Block plugin type manager
+  // enforces that delimiter for all derivatives.
+  $parts = explode(':', $variables['elements']['#plugin_id']);
+  $suggestion = 'block';
+  while ($part = array_shift($parts)) {
+    $suggestions[] = $suggestion .= '__' . strtr($part, '-', '_');
+  }
+
+  if (!empty($variables['elements']['#id'])) {
+    $suggestions[] = 'block__' . $variables['elements']['#id'];
+  }
+
+  return $suggestions;
+}
+
+/**
+ * Prepares variables for block templates.
+ *
+ * Default template: block.html.twig.
+ *
+ * Prepares the values passed to the theme_block function to be passed
+ * into a pluggable template engine. Uses block properties to generate a
+ * series of template file suggestions. If none are found, the default
+ * block.html.twig is used.
+ *
+ * Most themes use their own copy of block.html.twig. The default is located
+ * inside "core/modules/block/templates/block.html.twig". Look in there for the
+ * full list of available variables.
+ *
+ * @param array $variables
+ *   An associative array containing:
+ *   - elements: An associative array containing the properties of the element.
+ *     Properties used: #block, #configuration, #children, #plugin_id.
+ */
+function template_preprocess_block(&$variables) {
+  $variables['configuration'] = $variables['elements']['#configuration'];
+  $variables['plugin_id'] = $variables['elements']['#plugin_id'];
+  $variables['base_plugin_id'] = $variables['elements']['#base_plugin_id'];
+  $variables['derivative_plugin_id'] = $variables['elements']['#derivative_plugin_id'];
+  $variables['label'] = !empty($variables['configuration']['label_display']) ? $variables['configuration']['label'] : '';
+  $variables['content'] = $variables['elements']['content'];
+  // A block's label is configuration: it is static. Allow dynamic labels to be
+  // set in the render array.
+  if (isset($variables['elements']['content']['#title']) && !empty($variables['configuration']['label_display'])) {
+    $variables['label'] = $variables['elements']['content']['#title'];
+  }
+
+  // Create a valid HTML ID and make sure it is unique.
+  if (!empty($variables['elements']['#id'])) {
+    $variables['attributes']['id'] = Html::getUniqueId('block-' . $variables['elements']['#id']);
+  }
+
+  // Proactively add aria-describedby if possible to improve accessibility.
+  if ($variables['label'] && isset($variables['attributes']['role'])) {
+    $variables['title_attributes']['id'] = Html::getUniqueId($variables['label']);
+    $variables['attributes']['aria-describedby'] = $variables['title_attributes']['id'];
+  }
+
+}
+
+/**
+ * Implements hook_ENTITY_TYPE_delete() for user_role entities.
+ *
+ * Removes deleted role from blocks that use it.
+ */
+function block_user_role_delete($role) {
+  foreach (Block::loadMultiple() as $block) {
+    /** @var $block \Drupal\block\BlockInterface */
+    $visibility = $block->getVisibility();
+    if (isset($visibility['user_role']['roles'][$role->id()])) {
+      unset($visibility['user_role']['roles'][$role->id()]);
+      $block->setVisibilityConfig('user_role', $visibility['user_role']);
+      $block->save();
+    }
+  }
+}
+
+/**
+ * Implements hook_ENTITY_TYPE_delete() for menu entities.
+ */
+function block_menu_delete(Menu $menu) {
+  if (!$menu->isSyncing()) {
+    foreach (Block::loadMultiple() as $block) {
+      if ($block->getPluginId() == 'system_menu_block:' . $menu->id()) {
+        $block->delete();
+      }
+    }
+  }
+}
+
+/**
+ * Implements hook_ENTITY_TYPE_delete() for 'configurable_language'.
+ *
+ * Delete the potential block visibility settings of the deleted language.
+ */
+function block_configurable_language_delete(ConfigurableLanguageInterface $language) {
+  // Remove the block visibility settings for the deleted language.
+  foreach (Block::loadMultiple() as $block) {
+    /** @var $block \Drupal\block\BlockInterface */
+    $visibility = $block->getVisibility();
+    if (isset($visibility['language']['langcodes'][$language->id()])) {
+      unset($visibility['language']['langcodes'][$language->id()]);
+      $block->setVisibilityConfig('language', $visibility['language']);
+      $block->save();
+    }
+  }
+}

web/core/modules/block/block.permissions.yml

@@ -0,0 +1,2 @@
+administer blocks:
+  title: 'Administer blocks'

web/core/modules/block/block.post_update.php

@@ -0,0 +1,112 @@
+<?php
+
+/**
+ * @file
+ * Post update functions for Block.
+ */
+
+/**
+ * @addtogroup updates-8.0.0-beta
+ * @{
+ */
+
+/**
+ * Disable all blocks with missing context IDs in block_update_8001().
+ */
+function block_post_update_disable_blocks_with_missing_contexts() {
+  // Don't execute the function if block_update_8002() got executed already,
+  // which used to do the same. Note: Its okay to check here, because
+  // update_do_one() does not update the installed schema version until the
+  // batch is finished.
+  $module_schema = drupal_get_installed_schema_version('block');
+
+  // The state entry 'block_update_8002_placeholder' is used in order to
+  // indicate that the placeholder block_update_8002() function has been
+  // executed, so this function needs to be executed as well. If the non
+  // placeholder version of block_update_8002() got executed already, the state
+  // won't be set and we skip this update.
+  if ($module_schema >= 8002 && !\Drupal::state()->get('block_update_8002_placeholder', FALSE)) {
+    return;
+  }
+
+  // Cleanup the state entry as its no longer needed.
+  \Drupal::state()->delete('block_update_8002');
+
+  $block_update_8001 = \Drupal::keyValue('update_backup')->get('block_update_8001', []);
+
+  $block_ids = array_keys($block_update_8001);
+  $block_storage = \Drupal::entityManager()->getStorage('block');
+  $blocks = $block_storage->loadMultiple($block_ids);
+  /** @var $blocks \Drupal\block\BlockInterface[] */
+  foreach ($blocks as $block) {
+    // This block has had conditions removed due to an inability to resolve
+    // contexts in block_update_8001() so disable it.
+
+    // Disable currently enabled blocks.
+    if ($block_update_8001[$block->id()]['status']) {
+      $block->setStatus(FALSE);
+      $block->save();
+    }
+  }
+
+  // Provides a list of plugin labels, keyed by plugin ID.
+  $condition_plugin_id_label_map = array_column(\Drupal::service('plugin.manager.condition')->getDefinitions(), 'label', 'id');
+
+  // Override with the UI labels we are aware of. Sadly they are not machine
+  // accessible, see
+  // \Drupal\node\Plugin\Condition\NodeType::buildConfigurationForm().
+  $condition_plugin_id_label_map['node_type'] = t('Content types');
+  $condition_plugin_id_label_map['request_path'] = t('Pages');
+  $condition_plugin_id_label_map['user_role'] = t('Roles');
+
+  if (count($block_ids) > 0) {
+    $message = t('Encountered an unknown context mapping key coming probably from a contributed or custom module: One or more mappings could not be updated. Please manually review your visibility settings for the following blocks, which are disabled now:');
+    $message .= '<ul>';
+    foreach ($blocks as $disabled_block_id => $disabled_block) {
+      $message .= '<li>' . t('@label (Visibility: @plugin_ids)', array(
+          '@label' => $disabled_block->get('settings')['label'],
+          '@plugin_ids' => implode(', ', array_intersect_key($condition_plugin_id_label_map, array_flip(array_keys($block_update_8001[$disabled_block_id]['missing_context_ids']))))
+        )) . '</li>';
+    }
+    $message .= '</ul>';
+
+    return $message;
+  }
+}
+
+/**
+ * @} End of "addtogroup updates-8.0.0-beta".
+ */
+
+/**
+ * @addtogroup updates-8.2.x
+ * @{
+ */
+
+/**
+ * Fix invalid 'negate' values in block visibility conditions.
+ */
+function block_post_update_fix_negate_in_conditions() {
+  $block_storage = \Drupal::entityTypeManager()->getStorage('block');
+  /** @var \Drupal\block\BlockInterface[] $blocks */
+  $blocks = $block_storage->loadMultiple();
+  foreach ($blocks as $block) {
+    $block_needs_saving = FALSE;
+    // Check each visibility condition for an invalid negate value, and fix it.
+    foreach ($block->getVisibilityConditions() as $condition_id => $condition) {
+      $configuration = $condition->getConfiguration();
+      if (array_key_exists('negate', $configuration) && !is_bool($configuration['negate'])) {
+        $configuration['negate'] = (bool) $configuration['negate'];
+        $condition->setConfiguration($configuration);
+        $block_needs_saving = TRUE;
+      }
+    }
+    if ($block_needs_saving) {
+      $block->save();
+    }
+  }
+}
+
+/**
+ * @} End of "addtogroup updates-8.2.x".
+ */

web/core/modules/block/block.routing.yml

@@ -0,0 +1,68 @@
+block.admin_demo:
+  path: '/admin/structure/block/demo/{theme}'
+  defaults:
+    _controller: '\Drupal\block\Controller\BlockController::demo'
+    _title_callback: 'theme_handler:getName'
+  requirements:
+    _access_theme: 'TRUE'
+    _permission: 'administer blocks'
+  options:
+    _admin_route: FALSE
+
+entity.block.delete_form:
+  path: '/admin/structure/block/manage/{block}/delete'
+  defaults:
+    _entity_form: 'block.delete'
+    _title: 'Delete block'
+  requirements:
+    _permission: 'administer blocks'
+
+entity.block.edit_form:
+  path: '/admin/structure/block/manage/{block}'
+  defaults:
+    _entity_form: 'block.default'
+    _title: 'Configure block'
+  requirements:
+    _entity_access: 'block.update'
+
+block.admin_display:
+  path: '/admin/structure/block'
+  defaults:
+    _controller: '\Drupal\block\Controller\BlockListController::listing'
+    _title: 'Block layout'
+  requirements:
+    _permission: 'administer blocks'
+
+block.admin_display_theme:
+  path: 'admin/structure/block/list/{theme}'
+  defaults:
+    _controller: '\Drupal\block\Controller\BlockListController::listing'
+    _title: 'Block layout'
+  requirements:
+    _access_theme: 'TRUE'
+    _permission: 'administer blocks'
+
+block.admin_library:
+  path: 'admin/structure/block/library/{theme}'
+  defaults:
+    _controller: '\Drupal\block\Controller\BlockLibraryController::listBlocks'
+    _title: 'Place block'
+  requirements:
+    _access_theme: 'TRUE'
+    _permission: 'administer blocks'
+
+block.admin_add:
+  path: '/admin/structure/block/add/{plugin_id}/{theme}'
+  defaults:
+    _controller: '\Drupal\block\Controller\BlockAddController::blockAddConfigureForm'
+    theme: null
+    _title: 'Configure block'
+  requirements:
+    _permission: 'administer blocks'
+
+block.category_autocomplete:
+  path: '/block-category/autocomplete'
+  defaults:
+    _controller: '\Drupal\block\Controller\CategoryAutocompleteController::autocomplete'
+  requirements:
+    _permission: 'administer blocks'

web/core/modules/block/block.services.yml

@@ -0,0 +1,12 @@
+services:
+  theme.negotiator.block.admin_demo:
+    class: Drupal\block\Theme\AdminDemoNegotiator
+    tags:
+      - { name: theme_negotiator, priority: 1000 }
+  block.page_display_variant_subscriber:
+    class: Drupal\block\EventSubscriber\BlockPageDisplayVariantSubscriber
+    tags:
+      - { name: event_subscriber }
+  block.repository:
+    class: Drupal\block\BlockRepository
+    arguments: ['@entity.manager', '@theme.manager', '@context.handler']

web/core/modules/block/config/schema/block.schema.yml

@@ -0,0 +1,35 @@
+# Schema for the configuration files of the Block module.
+
+block.block.*:
+  type: config_entity
+  label: 'Block'
+  mapping:
+    id:
+      type: string
+      label: 'ID'
+    theme:
+      type: string
+      label: 'Theme'
+    region:
+      type: string
+      label: 'Region'
+    weight:
+      type: integer
+      label: 'Weight'
+    provider:
+      type: string
+      label: 'Provider'
+    plugin:
+      type: string
+      label: 'Plugin'
+    settings:
+      type: block.settings.[%parent.plugin]
+    visibility:
+      type: sequence
+      label: 'Visibility Conditions'
+      sequence:
+        type: condition.plugin.[id]
+        label: 'Visibility Condition'
+
+block.settings.*:
+  type: block_settings

web/core/modules/block/css/block.admin.css

@@ -0,0 +1,42 @@
+/* Block listing page */
+.region-title__action {
+  display: inline-block;
+  margin-left: 1em; /* LTR */
+}
+[dir="rtl"] .region-title__action {
+  margin-left: 0;
+  margin-right: 1em;
+}
+
+/* Block demo mode */
+.block-region {
+  background-color: #ff6;
+  margin-top: 4px;
+  margin-bottom: 4px;
+  padding: 3px;
+}
+a.block-demo-backlink,
+a.block-demo-backlink:link,
+a.block-demo-backlink:visited {
+  background-color: #b4d7f0;
+  border-radius: 0 0 10px 10px;
+  color: #000;
+  font-family: "Lucida Grande", Verdana, sans-serif;
+  font-size: small;
+  line-height: 20px;
+  left: 20px; /*LTR*/
+  padding: 5px 10px;
+  position: fixed;
+  z-index: 499;
+}
+a.block-demo-backlink:hover {
+  text-decoration: underline;
+}
+
+/* Configure block form - Block description */
+.block-form .form-item-settings-admin-label label {
+  display: inline;
+}
+.block-form .form-item-settings-admin-label label:after {
+  content: ':';
+}

web/core/modules/block/js/block.admin.js

@@ -0,0 +1,97 @@
+/**
+ * @file
+ * Block admin behaviors.
+ */
+
+(function ($, Drupal) {
+
+  'use strict';
+
+  /**
+   * Filters the block list by a text input search string.
+   *
+   * The text input will have the selector `input.block-filter-text`.
+   *
+   * The target element to do searching in will be in the selector
+   * `input.block-filter-text[data-element]`
+   *
+   * The text source where the text should be found will have the selector
+   * `.block-filter-text-source`
+   *
+   * @type {Drupal~behavior}
+   *
+   * @prop {Drupal~behaviorAttach} attach
+   *   Attaches the behavior for the block filtering.
+   */
+  Drupal.behaviors.blockFilterByText = {
+    attach: function (context, settings) {
+      var $input = $('input.block-filter-text').once('block-filter-text');
+      var $table = $($input.attr('data-element'));
+      var $filter_rows;
+
+      /**
+       * Filters the block list.
+       *
+       * @param {jQuery.Event} e
+       *   The jQuery event for the keyup event that triggered the filter.
+       */
+      function filterBlockList(e) {
+        var query = $(e.target).val().toLowerCase();
+
+        /**
+         * Shows or hides the block entry based on the query.
+         *
+         * @param {number} index
+         *   The index in the loop, as provided by `jQuery.each`
+         * @param {HTMLElement} label
+         *   The label of the block.
+         */
+        function toggleBlockEntry(index, label) {
+          var $label = $(label);
+          var $row = $label.parent().parent();
+          var textMatch = $label.text().toLowerCase().indexOf(query) !== -1;
+          $row.toggle(textMatch);
+        }
+
+        // Filter if the length of the query is at least 2 characters.
+        if (query.length >= 2) {
+          $filter_rows.each(toggleBlockEntry);
+        }
+        else {
+          $filter_rows.each(function (index) {
+            $(this).parent().parent().show();
+          });
+        }
+      }
+
+      if ($table.length) {
+        $filter_rows = $table.find('div.block-filter-text-source');
+        $input.on('keyup', filterBlockList);
+      }
+    }
+  };
+
+  /**
+   * Highlights the block that was just placed into the block listing.
+   *
+   * @type {Drupal~behavior}
+   *
+   * @prop {Drupal~behaviorAttach} attach
+   *   Attaches the behavior for the block placement highlighting.
+   */
+  Drupal.behaviors.blockHighlightPlacement = {
+    attach: function (context, settings) {
+      if (settings.blockPlacement) {
+        $(context).find('[data-drupal-selector="edit-blocks"]').once('block-highlight').each(function () {
+          var $container = $(this);
+          // Just scrolling the document.body will not work in Firefox. The html
+          // element is needed as well.
+          $('html, body').animate({
+            scrollTop: $('.js-block-placed').offset().top - $container.offset().top + $container.scrollTop()
+          }, 500);
+        });
+      }
+    }
+  };
+
+}(jQuery, Drupal));

web/core/modules/block/js/block.js

@@ -0,0 +1,228 @@
+/**
+ * @file
+ * Block behaviors.
+ */
+
+(function ($, window, Drupal) {
+
+  'use strict';
+
+  /**
+   * Provide the summary information for the block settings vertical tabs.
+   *
+   * @type {Drupal~behavior}
+   *
+   * @prop {Drupal~behaviorAttach} attach
+   *   Attaches the behavior for the block settings summaries.
+   */
+  Drupal.behaviors.blockSettingsSummary = {
+    attach: function () {
+      // The drupalSetSummary method required for this behavior is not available
+      // on the Blocks administration page, so we need to make sure this
+      // behavior is processed only if drupalSetSummary is defined.
+      if (typeof $.fn.drupalSetSummary === 'undefined') {
+        return;
+      }
+
+      /**
+       * Create a summary for checkboxes in the provided context.
+       *
+       * @param {HTMLDocument|HTMLElement} context
+       *   A context where one would find checkboxes to summarize.
+       *
+       * @return {string}
+       *   A string with the summary.
+       */
+      function checkboxesSummary(context) {
+        var vals = [];
+        var $checkboxes = $(context).find('input[type="checkbox"]:checked + label');
+        var il = $checkboxes.length;
+        for (var i = 0; i < il; i++) {
+          vals.push($($checkboxes[i]).html());
+        }
+        if (!vals.length) {
+          vals.push(Drupal.t('Not restricted'));
+        }
+        return vals.join(', ');
+      }
+
+      $('[data-drupal-selector="edit-visibility-node-type"], [data-drupal-selector="edit-visibility-language"], [data-drupal-selector="edit-visibility-user-role"]').drupalSetSummary(checkboxesSummary);
+
+      $('[data-drupal-selector="edit-visibility-request-path"]').drupalSetSummary(function (context) {
+        var $pages = $(context).find('textarea[name="visibility[request_path][pages]"]');
+        if (!$pages.val()) {
+          return Drupal.t('Not restricted');
+        }
+        else {
+          return Drupal.t('Restricted to certain pages');
+        }
+      });
+    }
+  };
+
+  /**
+   * Move a block in the blocks table between regions via select list.
+   *
+   * This behavior is dependent on the tableDrag behavior, since it uses the
+   * objects initialized in that behavior to update the row.
+   *
+   * @type {Drupal~behavior}
+   *
+   * @prop {Drupal~behaviorAttach} attach
+   *   Attaches the tableDrag behaviour for blocks in block administration.
+   */
+  Drupal.behaviors.blockDrag = {
+    attach: function (context, settings) {
+      // tableDrag is required and we should be on the blocks admin page.
+      if (typeof Drupal.tableDrag === 'undefined' || typeof Drupal.tableDrag.blocks === 'undefined') {
+        return;
+      }
+
+      /**
+       * Function to check empty regions and toggle classes based on this.
+       *
+       * @param {jQuery} table
+       *   The jQuery object representing the table to inspect.
+       * @param {jQuery} rowObject
+       *   The jQuery object representing the table row.
+       */
+      function checkEmptyRegions(table, rowObject) {
+        table.find('tr.region-message').each(function () {
+          var $this = $(this);
+          // If the dragged row is in this region, but above the message row,
+          // swap it down one space.
+          if ($this.prev('tr').get(0) === rowObject.element) {
+            // Prevent a recursion problem when using the keyboard to move rows
+            // up.
+            if ((rowObject.method !== 'keyboard' || rowObject.direction === 'down')) {
+              rowObject.swap('after', this);
+            }
+          }
+          // This region has become empty.
+          if ($this.next('tr').is(':not(.draggable)') || $this.next('tr').length === 0) {
+            $this.removeClass('region-populated').addClass('region-empty');
+          }
+          // This region has become populated.
+          else if ($this.is('.region-empty')) {
+            $this.removeClass('region-empty').addClass('region-populated');
+          }
+        });
+      }
+
+      /**
+       * Function to update the last placed row with the correct classes.
+       *
+       * @param {jQuery} table
+       *   The jQuery object representing the table to inspect.
+       * @param {jQuery} rowObject
+       *   The jQuery object representing the table row.
+       */
+      function updateLastPlaced(table, rowObject) {
+        // Remove the color-success class from new block if applicable.
+        table.find('.color-success').removeClass('color-success');
+
+        var $rowObject = $(rowObject);
+        if (!$rowObject.is('.drag-previous')) {
+          table.find('.drag-previous').removeClass('drag-previous');
+          $rowObject.addClass('drag-previous');
+        }
+      }
+
+      /**
+       * Update block weights in the given region.
+       *
+       * @param {jQuery} table
+       *   Table with draggable items.
+       * @param {string} region
+       *   Machine name of region containing blocks to update.
+       */
+      function updateBlockWeights(table, region) {
+        // Calculate minimum weight.
+        var weight = -Math.round(table.find('.draggable').length / 2);
+        // Update the block weights.
+        table.find('.region-' + region + '-message').nextUntil('.region-title')
+          .find('select.block-weight').val(function () {
+            // Increment the weight before assigning it to prevent using the
+            // absolute minimum available weight. This way we always have an
+            // unused upper and lower bound, which makes manually setting the
+            // weights easier for users who prefer to do it that way.
+            return ++weight;
+          });
+      }
+
+      var table = $('#blocks');
+      // Get the blocks tableDrag object.
+      var tableDrag = Drupal.tableDrag.blocks;
+      // Add a handler for when a row is swapped, update empty regions.
+      tableDrag.row.prototype.onSwap = function (swappedRow) {
+        checkEmptyRegions(table, this);
+        updateLastPlaced(table, this);
+      };
+
+      // Add a handler so when a row is dropped, update fields dropped into
+      // new regions.
+      tableDrag.onDrop = function () {
+        var dragObject = this;
+        var $rowElement = $(dragObject.rowObject.element);
+        // Use "region-message" row instead of "region" row because
+        // "region-{region_name}-message" is less prone to regexp match errors.
+        var regionRow = $rowElement.prevAll('tr.region-message').get(0);
+        var regionName = regionRow.className.replace(/([^ ]+[ ]+)*region-([^ ]+)-message([ ]+[^ ]+)*/, '$2');
+        var regionField = $rowElement.find('select.block-region-select');
+        // Check whether the newly picked region is available for this block.
+        if (regionField.find('option[value=' + regionName + ']').length === 0) {
+          // If not, alert the user and keep the block in its old region
+          // setting.
+          window.alert(Drupal.t('The block cannot be placed in this region.'));
+          // Simulate that there was a selected element change, so the row is
+          // put back to from where the user tried to drag it.
+          regionField.trigger('change');
+        }
+
+        // Update region and weight fields if the region has been changed.
+        if (!regionField.is('.block-region-' + regionName)) {
+          var weightField = $rowElement.find('select.block-weight');
+          var oldRegionName = weightField[0].className.replace(/([^ ]+[ ]+)*block-weight-([^ ]+)([ ]+[^ ]+)*/, '$2');
+          regionField.removeClass('block-region-' + oldRegionName).addClass('block-region-' + regionName);
+          weightField.removeClass('block-weight-' + oldRegionName).addClass('block-weight-' + regionName);
+          regionField.val(regionName);
+        }
+
+        updateBlockWeights(table, regionName);
+      };
+
+      // Add the behavior to each region select list.
+      $(context).find('select.block-region-select').once('block-region-select')
+        .on('change', function (event) {
+          // Make our new row and select field.
+          var row = $(this).closest('tr');
+          var select = $(this);
+          // Find the correct region and insert the row as the last in the
+          // region.
+          tableDrag.rowObject = new tableDrag.row(row[0]);
+          var region_message = table.find('.region-' + select[0].value + '-message');
+          var region_items = region_message.nextUntil('.region-message, .region-title');
+          if (region_items.length) {
+            region_items.last().after(row);
+          }
+          // We found that region_message is the last row.
+          else {
+            region_message.after(row);
+          }
+          updateBlockWeights(table, select[0].value);
+          // Modify empty regions with added or removed fields.
+          checkEmptyRegions(table, tableDrag.rowObject);
+          // Update last placed block indication.
+          updateLastPlaced(table, row);
+          // Show unsaved changes warning.
+          if (!tableDrag.changed) {
+            $(Drupal.theme('tableDragChangedWarning')).insertBefore(tableDrag.table).hide().fadeIn('slow');
+            tableDrag.changed = true;
+          }
+          // Remove focus from selectbox.
+          select.trigger('blur');
+        });
+    }
+  };
+
+})(jQuery, window, Drupal);

web/core/modules/block/migration_templates/d6_block.yml

@@ -0,0 +1,102 @@
+id: d6_block
+label: Blocks
+migration_tags:
+  - Drupal 6
+source:
+  plugin: block
+process:
+  # Block status is not a thing in Drupal 8, so this is how we skip over
+  # disabled blocks.
+  status:
+    plugin: skip_on_empty
+    method: row
+    source: status
+  id:
+    # We need something unique, so aggregator, aggregator_1 etc will do.
+    plugin: dedupe_entity
+    entity_type: block
+    field: id
+    postfix: _
+    length: 32
+    source: module
+  plugin:
+    -
+      plugin: static_map
+      bypass: true
+      source:
+        - module
+        - delta
+      map:
+        book:
+          0: book_navigation
+        comment:
+          0: views_block:comments_recent-block_1
+        forum:
+          0: forum_active_block
+          1: forum_new_block
+        locale:
+          0: language_block
+        node:
+          0: node_syndicate_block
+        search:
+          0: search_form_block
+        statistics:
+          0: statistics_popular_block
+        system:
+          0: system_powered_by_block
+        user:
+          0: user_login_block
+          1: system_menu_block:tools
+          2: views_block:who_s_new-block_1
+          3: views_block:who_s_online-who_s_online_block
+    -
+      plugin: block_plugin_id
+    -
+      plugin: skip_on_empty
+      method: row
+  theme:
+    plugin: block_theme
+    source:
+      - theme
+      - default_theme
+      - admin_theme
+  region:
+    plugin: block_region
+    source:
+      - theme
+      - '@theme'
+      - region
+    map:
+      garland:
+        bartik:
+          # Garland 6.x --> Bartik 8.x
+          header: header
+          footer: footer_fifth
+          left: sidebar_first
+          right: sidebar_second
+    # If mapping fails, put the block in the content region.
+    default_value: content
+  weight: weight
+  settings:
+    plugin: block_settings
+    source:
+      - '@plugin'
+      - delta
+      - settings
+      - title
+  visibility:
+    plugin: block_visibility
+    source:
+      - visibility
+      - pages
+      - roles
+    # If the block uses PHP visibility, don't migrate it unless the PHP module
+    # is enabled.
+    skip_php: true
+destination:
+  plugin: entity:block
+migration_dependencies:
+  required:
+    - menu
+    - d6_custom_block
+    - d6_user_role

web/core/modules/block/migration_templates/d7_block.yml

@@ -0,0 +1,110 @@
+id: d7_block
+label: Blocks
+migration_tags:
+  - Drupal 7
+source:
+  plugin: block
+process:
+  # Block status is not a thing in Drupal 8, so this is how we skip over
+  # disabled blocks.
+  status:
+    plugin: skip_on_empty
+    method: row
+    source: status
+  id:
+    -
+      plugin: concat
+      source:
+        - theme
+        - module
+        - delta
+      delimiter: _
+    -
+      plugin: machine_name
+      field: id
+  plugin:
+    -
+      plugin: static_map
+      bypass: true
+      source:
+        - module
+        - delta
+      map:
+        book:
+          navigation: book_navigation
+        comment:
+          recent: views_block:comments_recent-block_1
+        forum:
+          active: forum_active_block
+          new: forum_new_block
+        # locale:
+        #  0: language_block
+        node:
+          syndicate: node_syndicate_block
+        search:
+          form: search_form_block
+        statistics:
+          popular: statistics_popular_block
+        system:
+          main: system_main_block
+          'powered-by': system_powered_by_block
+        user:
+          login: user_login_block
+          # 1: system_menu_block:tools
+          new: views_block:who_s_new-block_1
+          online: views_block:who_s_online-who_s_online_block
+    -
+      plugin: block_plugin_id
+    -
+      plugin: skip_on_empty
+      method: row
+  theme:
+    plugin: block_theme
+    source:
+      - theme
+      - default_theme
+      - admin_theme
+  region:
+    plugin: block_region
+    source:
+      - theme
+      - '@theme'
+      - region
+    map:
+      bartik:
+        bartik:
+          # Bartik 7.x --> Bartik 8.x
+          featured: featured_top
+          triptych_first: featured_bottom_first
+          triptych_middle: featured_bottom_second
+          triptych_last: featured_bottom_third
+          footer_firstcolumn: footer_first
+          footer_secondcolumn: footer_second
+          footer_thirdcolumn: footer_third
+          footer_fourthcolumn: footer_fourth
+          footer: footer_fifth
+    # If mapping fails, put the block in the content region.
+    default_value: content
+  weight: weight
+  settings:
+    plugin: block_settings
+    source:
+      - '@plugin'
+      - delta
+      - settings
+      - title
+  visibility:
+    plugin: block_visibility
+    source:
+      - visibility
+      - pages
+      - roles
+    # If the block uses PHP visibility, don't migrate it unless the PHP module
+    # is enabled.
+    skip_php: true
+destination:
+  plugin: entity:block
+migration_dependencies:
+  optional:
+    - d7_custom_block
+    - d7_user_role

web/core/modules/block/src/BlockAccessControlHandler.php

@@ -0,0 +1,171 @@
+<?php
+
+namespace Drupal\block;
+
+use Drupal\Component\Plugin\Exception\ContextException;
+use Drupal\Core\Access\AccessResult;
+use Drupal\Core\Cache\Cache;
+use Drupal\Core\Cache\CacheableDependencyInterface;
+use Drupal\Core\Condition\ConditionAccessResolverTrait;
+use Drupal\Core\Entity\EntityAccessControlHandler;
+use Drupal\Core\Entity\EntityHandlerInterface;
+use Drupal\Core\Entity\EntityInterface;
+use Drupal\Core\Entity\EntityTypeInterface;
+use Drupal\Core\Executable\ExecutableManagerInterface;
+use Drupal\Core\Plugin\Context\ContextHandlerInterface;
+use Drupal\Core\Plugin\Context\ContextRepositoryInterface;
+use Drupal\Core\Plugin\ContextAwarePluginInterface;
+use Drupal\Core\Session\AccountInterface;
+use Symfony\Component\DependencyInjection\ContainerInterface;
+
+/**
+ * Defines the access control handler for the block entity type.
+ *
+ * @see \Drupal\block\Entity\Block
+ */
+class BlockAccessControlHandler extends EntityAccessControlHandler implements EntityHandlerInterface {
+
+  use ConditionAccessResolverTrait;
+
+  /**
+   * The condition plugin manager.
+   *
+   * @var \Drupal\Core\Executable\ExecutableManagerInterface
+   */
+  protected $manager;
+
+  /**
+   * The plugin context handler.
+   *
+   * @var \Drupal\Core\Plugin\Context\ContextHandlerInterface
+   */
+  protected $contextHandler;
+
+  /**
+   * The context manager service.
+   *
+   * @var \Drupal\Core\Plugin\Context\ContextRepositoryInterface
+   */
+  protected $contextRepository;
+
+  /**
+   * {@inheritdoc}
+   */
+  public static function createInstance(ContainerInterface $container, EntityTypeInterface $entity_type) {
+    return new static(
+      $entity_type,
+      $container->get('plugin.manager.condition'),
+      $container->get('context.handler'),
+      $container->get('context.repository')
+    );
+  }
+
+  /**
+   * Constructs the block access control handler instance
+   *
+   * @param \Drupal\Core\Entity\EntityTypeInterface $entity_type
+   *   The entity type definition.
+   * @param \Drupal\Core\Executable\ExecutableManagerInterface $manager
+   *   The ConditionManager for checking visibility of blocks.
+   * @param \Drupal\Core\Plugin\Context\ContextHandlerInterface $context_handler
+   *   The ContextHandler for applying contexts to conditions properly.
+   * @param \Drupal\Core\Plugin\Context\ContextRepositoryInterface $context_repository
+   *   The lazy context repository service.
+   */
+  public function __construct(EntityTypeInterface $entity_type, ExecutableManagerInterface $manager, ContextHandlerInterface $context_handler, ContextRepositoryInterface $context_repository ) {
+    parent::__construct($entity_type);
+    $this->manager = $manager;
+    $this->contextHandler = $context_handler;
+    $this->contextRepository = $context_repository;
+  }
+
+
+  /**
+   * {@inheritdoc}
+   */
+  protected function checkAccess(EntityInterface $entity, $operation, AccountInterface $account) {
+    /** @var \Drupal\block\BlockInterface $entity */
+    if ($operation != 'view') {
+      return parent::checkAccess($entity, $operation, $account);
+    }
+
+    // Don't grant access to disabled blocks.
+    if (!$entity->status()) {
+      return AccessResult::forbidden()->addCacheableDependency($entity);
+    }
+    else {
+      $conditions = [];
+      $missing_context = FALSE;
+      foreach ($entity->getVisibilityConditions() as $condition_id => $condition) {
+        if ($condition instanceof ContextAwarePluginInterface) {
+          try {
+            $contexts = $this->contextRepository->getRuntimeContexts(array_values($condition->getContextMapping()));
+            $this->contextHandler->applyContextMapping($condition, $contexts);
+          }
+          catch (ContextException $e) {
+            $missing_context = TRUE;
+          }
+        }
+        $conditions[$condition_id] = $condition;
+      }
+
+      if ($missing_context) {
+        // If any context is missing then we might be missing cacheable
+        // metadata, and don't know based on what conditions the block is
+        // accessible or not. For example, blocks that have a node type
+        // condition will have a missing context on any non-node route like the
+        // frontpage.
+        // @todo Avoid setting max-age 0 for some or all cases, for example by
+        //   treating available contexts without value differently in
+        //   https://www.drupal.org/node/2521956.
+        $access = AccessResult::forbidden()->setCacheMaxAge(0);
+      }
+      elseif ($this->resolveConditions($conditions, 'and') !== FALSE) {
+        // Delegate to the plugin.
+        $block_plugin = $entity->getPlugin();
+        try {
+          if ($block_plugin instanceof ContextAwarePluginInterface) {
+            $contexts = $this->contextRepository->getRuntimeContexts(array_values($block_plugin->getContextMapping()));
+            $this->contextHandler->applyContextMapping($block_plugin, $contexts);
+          }
+          $access = $block_plugin->access($account, TRUE);
+        }
+        catch (ContextException $e) {
+          // Setting access to forbidden if any context is missing for the same
+          // reasons as with conditions (described in the comment above).
+          // @todo Avoid setting max-age 0 for some or all cases, for example by
+          //   treating available contexts without value differently in
+          //   https://www.drupal.org/node/2521956.
+          $access = AccessResult::forbidden()->setCacheMaxAge(0);
+        }
+      }
+      else {
+        $access = AccessResult::forbidden();
+      }
+
+      $this->mergeCacheabilityFromConditions($access, $conditions);
+
+      // Ensure that access is evaluated again when the block changes.
+      return $access->addCacheableDependency($entity);
+    }
+  }
+
+  /**
+   * Merges cacheable metadata from conditions onto the access result object.
+   *
+   * @param \Drupal\Core\Access\AccessResult $access
+   *   The access result object.
+   * @param \Drupal\Core\Condition\ConditionInterface[] $conditions
+   *   List of visibility conditions.
+   */
+  protected function mergeCacheabilityFromConditions(AccessResult $access, array $conditions) {
+    foreach ($conditions as $condition) {
+      if ($condition instanceof CacheableDependencyInterface) {
+        $access->addCacheTags($condition->getCacheTags());
+        $access->addCacheContexts($condition->getCacheContexts());
+        $access->setCacheMaxAge(Cache::mergeMaxAges($access->getCacheMaxAge(), $condition->getCacheMaxAge()));
+      }
+    }
+  }
+
+}

web/core/modules/block/src/BlockForm.php

@@ -0,0 +1,447 @@
+<?php
+
+namespace Drupal\block;
+
+use Drupal\Component\Utility\Html;
+use Drupal\Core\Plugin\PluginFormFactoryInterface;
+use Drupal\Core\Block\BlockPluginInterface;
+use Drupal\Core\Entity\EntityForm;
+use Drupal\Core\Entity\EntityManagerInterface;
+use Drupal\Core\Executable\ExecutableManagerInterface;
+use Drupal\Core\Extension\ThemeHandlerInterface;
+use Drupal\Core\Form\FormStateInterface;
+use Drupal\Core\Form\SubformState;
+use Drupal\Core\Language\LanguageManagerInterface;
+use Drupal\Core\Plugin\ContextAwarePluginInterface;
+use Drupal\Core\Plugin\Context\ContextRepositoryInterface;
+use Drupal\Core\Plugin\PluginWithFormsInterface;
+use Symfony\Component\DependencyInjection\ContainerInterface;
+
+/**
+ * Provides form for block instance forms.
+ */
+class BlockForm extends EntityForm {
+
+  /**
+   * The block entity.
+   *
+   * @var \Drupal\block\BlockInterface
+   */
+  protected $entity;
+
+  /**
+   * The block storage.
+   *
+   * @var \Drupal\Core\Entity\EntityStorageInterface
+   */
+  protected $storage;
+
+  /**
+   * The condition plugin manager.
+   *
+   * @var \Drupal\Core\Condition\ConditionManager
+   */
+  protected $manager;
+
+  /**
+   * The event dispatcher service.
+   *
+   * @var \Symfony\Component\EventDispatcher\EventDispatcherInterface
+   */
+  protected $dispatcher;
+
+  /**
+   * The language manager service.
+   *
+   * @var \Drupal\Core\Language\LanguageManagerInterface
+   */
+  protected $language;
+
+  /**
+   * The theme handler.
+   *
+   * @var \Drupal\Core\Extension\ThemeHandler
+   */
+  protected $themeHandler;
+
+  /**
+   * The context repository service.
+   *
+   * @var \Drupal\Core\Plugin\Context\ContextRepositoryInterface
+   */
+  protected $contextRepository;
+
+  /**
+   * The plugin form manager.
+   *
+   * @var \Drupal\Core\Plugin\PluginFormFactoryInterface
+   */
+  protected $pluginFormFactory;
+
+  /**
+   * Constructs a BlockForm object.
+   *
+   * @param \Drupal\Core\Entity\EntityManagerInterface $entity_manager
+   *   The entity manager.
+   * @param \Drupal\Core\Executable\ExecutableManagerInterface $manager
+   *   The ConditionManager for building the visibility UI.
+   * @param \Drupal\Core\Plugin\Context\ContextRepositoryInterface $context_repository
+   *   The lazy context repository service.
+   * @param \Drupal\Core\Language\LanguageManagerInterface $language
+   *   The language manager.
+   * @param \Drupal\Core\Extension\ThemeHandlerInterface $theme_handler
+   *   The theme handler.
+   * @param \Drupal\Core\Plugin\PluginFormFactoryInterface $plugin_form_manager
+   *   The plugin form manager.
+   */
+  public function __construct(EntityManagerInterface $entity_manager, ExecutableManagerInterface $manager, ContextRepositoryInterface $context_repository, LanguageManagerInterface $language, ThemeHandlerInterface $theme_handler, PluginFormFactoryInterface $plugin_form_manager) {
+    $this->storage = $entity_manager->getStorage('block');
+    $this->manager = $manager;
+    $this->contextRepository = $context_repository;
+    $this->language = $language;
+    $this->themeHandler = $theme_handler;
+    $this->pluginFormFactory = $plugin_form_manager;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public static function create(ContainerInterface $container) {
+    return new static(
+      $container->get('entity.manager'),
+      $container->get('plugin.manager.condition'),
+      $container->get('context.repository'),
+      $container->get('language_manager'),
+      $container->get('theme_handler'),
+      $container->get('plugin_form.factory')
+    );
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function form(array $form, FormStateInterface $form_state) {
+    $entity = $this->entity;
+
+    // Store theme settings in $form_state for use below.
+    if (!$theme = $entity->getTheme()) {
+      $theme = $this->config('system.theme')->get('default');
+    }
+    $form_state->set('block_theme', $theme);
+
+    // Store the gathered contexts in the form state for other objects to use
+    // during form building.
+    $form_state->setTemporaryValue('gathered_contexts', $this->contextRepository->getAvailableContexts());
+
+    $form['#tree'] = TRUE;
+    $form['settings'] = [];
+    $subform_state = SubformState::createForSubform($form['settings'], $form, $form_state);
+    $form['settings'] = $this->getPluginForm($entity->getPlugin())->buildConfigurationForm($form['settings'], $subform_state);
+    $form['visibility'] = $this->buildVisibilityInterface([], $form_state);
+
+    // If creating a new block, calculate a safe default machine name.
+    $form['id'] = array(
+      '#type' => 'machine_name',
+      '#maxlength' => 64,
+      '#description' => $this->t('A unique name for this block instance. Must be alpha-numeric and underscore separated.'),
+      '#default_value' => !$entity->isNew() ? $entity->id() : $this->getUniqueMachineName($entity),
+      '#machine_name' => array(
+        'exists' => '\Drupal\block\Entity\Block::load',
+        'replace_pattern' => '[^a-z0-9_.]+',
+        'source' => array('settings', 'label'),
+      ),
+      '#required' => TRUE,
+      '#disabled' => !$entity->isNew(),
+    );
+
+    // Theme settings.
+    if ($entity->getTheme()) {
+      $form['theme'] = array(
+        '#type' => 'value',
+        '#value' => $theme,
+      );
+    }
+    else {
+      $theme_options = array();
+      foreach ($this->themeHandler->listInfo() as $theme_name => $theme_info) {
+        if (!empty($theme_info->status)) {
+          $theme_options[$theme_name] = $theme_info->info['name'];
+        }
+      }
+      $form['theme'] = array(
+        '#type' => 'select',
+        '#options' => $theme_options,
+        '#title' => t('Theme'),
+        '#default_value' => $theme,
+        '#ajax' => array(
+          'callback' => '::themeSwitch',
+          'wrapper' => 'edit-block-region-wrapper',
+        ),
+      );
+    }
+
+    // Hidden weight setting.
+    $weight = $entity->isNew() ? $this->getRequest()->query->get('weight', 0) : $entity->getWeight();
+    $form['weight'] = array(
+      '#type' => 'hidden',
+      '#default_value' => $weight,
+    );
+
+    // Region settings.
+    $entity_region = $entity->getRegion();
+    $region = $entity->isNew() ? $this->getRequest()->query->get('region', $entity_region) : $entity_region;
+    $form['region'] = array(
+      '#type' => 'select',
+      '#title' => $this->t('Region'),
+      '#description' => $this->t('Select the region where this block should be displayed.'),
+      '#default_value' => $region,
+      '#empty_value' => BlockInterface::BLOCK_REGION_NONE,
+      '#options' => system_region_list($theme, REGIONS_VISIBLE),
+      '#prefix' => '<div id="edit-block-region-wrapper">',
+      '#suffix' => '</div>',
+    );
+    $form['#attached']['library'][] = 'block/drupal.block.admin';
+    return $form;
+  }
+
+  /**
+   * Handles switching the available regions based on the selected theme.
+   */
+  public function themeSwitch($form, FormStateInterface $form_state) {
+    $form['region']['#options'] = system_region_list($form_state->getValue('theme'), REGIONS_VISIBLE);
+    return $form['region'];
+  }
+
+  /**
+   * Helper function for building the visibility UI form.
+   *
+   * @param array $form
+   *   An associative array containing the structure of the form.
+   * @param \Drupal\Core\Form\FormStateInterface $form_state
+   *   The current state of the form.
+   *
+   * @return array
+   *   The form array with the visibility UI added in.
+   */
+  protected function buildVisibilityInterface(array $form, FormStateInterface $form_state) {
+    $form['visibility_tabs'] = [
+      '#type' => 'vertical_tabs',
+      '#title' => $this->t('Visibility'),
+      '#parents' => ['visibility_tabs'],
+      '#attached' => [
+        'library' => [
+          'block/drupal.block',
+        ],
+      ],
+    ];
+    // @todo Allow list of conditions to be configured in
+    //   https://www.drupal.org/node/2284687.
+    $visibility = $this->entity->getVisibility();
+    foreach ($this->manager->getDefinitionsForContexts($form_state->getTemporaryValue('gathered_contexts')) as $condition_id => $definition) {
+      // Don't display the current theme condition.
+      if ($condition_id == 'current_theme') {
+        continue;
+      }
+      // Don't display the language condition until we have multiple languages.
+      if ($condition_id == 'language' && !$this->language->isMultilingual()) {
+        continue;
+      }
+      /** @var \Drupal\Core\Condition\ConditionInterface $condition */
+      $condition = $this->manager->createInstance($condition_id, isset($visibility[$condition_id]) ? $visibility[$condition_id] : []);
+      $form_state->set(['conditions', $condition_id], $condition);
+      $condition_form = $condition->buildConfigurationForm([], $form_state);
+      $condition_form['#type'] = 'details';
+      $condition_form['#title'] = $condition->getPluginDefinition()['label'];
+      $condition_form['#group'] = 'visibility_tabs';
+      $form[$condition_id] = $condition_form;
+    }
+
+    if (isset($form['node_type'])) {
+      $form['node_type']['#title'] = $this->t('Content types');
+      $form['node_type']['bundles']['#title'] = $this->t('Content types');
+      $form['node_type']['negate']['#type'] = 'value';
+      $form['node_type']['negate']['#title_display'] = 'invisible';
+      $form['node_type']['negate']['#value'] = $form['node_type']['negate']['#default_value'];
+    }
+    if (isset($form['user_role'])) {
+      $form['user_role']['#title'] = $this->t('Roles');
+      unset($form['user_role']['roles']['#description']);
+      $form['user_role']['negate']['#type'] = 'value';
+      $form['user_role']['negate']['#value'] = $form['user_role']['negate']['#default_value'];
+    }
+    if (isset($form['request_path'])) {
+      $form['request_path']['#title'] = $this->t('Pages');
+      $form['request_path']['negate']['#type'] = 'radios';
+      $form['request_path']['negate']['#default_value'] = (int) $form['request_path']['negate']['#default_value'];
+      $form['request_path']['negate']['#title_display'] = 'invisible';
+      $form['request_path']['negate']['#options'] = [
+        $this->t('Show for the listed pages'),
+        $this->t('Hide for the listed pages'),
+      ];
+    }
+    if (isset($form['language'])) {
+      $form['language']['negate']['#type'] = 'value';
+      $form['language']['negate']['#value'] = $form['language']['negate']['#default_value'];
+    }
+    return $form;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  protected function actions(array $form, FormStateInterface $form_state) {
+    $actions = parent::actions($form, $form_state);
+    $actions['submit']['#value'] = $this->t('Save block');
+    return $actions;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function validateForm(array &$form, FormStateInterface $form_state) {
+    parent::validateForm($form, $form_state);
+
+    $form_state->setValue('weight', (int) $form_state->getValue('weight'));
+    // The Block Entity form puts all block plugin form elements in the
+    // settings form element, so just pass that to the block for validation.
+    $this->getPluginForm($this->entity->getPlugin())->validateConfigurationForm($form['settings'], SubformState::createForSubform($form['settings'], $form, $form_state));
+    $this->validateVisibility($form, $form_state);
+  }
+
+  /**
+   * Helper function to independently validate the visibility UI.
+   *
+   * @param array $form
+   *   A nested array form elements comprising the form.
+   * @param \Drupal\Core\Form\FormStateInterface $form_state
+   *   The current state of the form.
+   */
+  protected function validateVisibility(array $form, FormStateInterface $form_state) {
+    // Validate visibility condition settings.
+    foreach ($form_state->getValue('visibility') as $condition_id => $values) {
+      // All condition plugins use 'negate' as a Boolean in their schema.
+      // However, certain form elements may return it as 0/1. Cast here to
+      // ensure the data is in the expected type.
+      if (array_key_exists('negate', $values)) {
+        $form_state->setValue(['visibility', $condition_id, 'negate'], (bool) $values['negate']);
+      }
+
+      // Allow the condition to validate the form.
+      $condition = $form_state->get(['conditions', $condition_id]);
+      $condition->validateConfigurationForm($form['visibility'][$condition_id], SubformState::createForSubform($form['visibility'][$condition_id], $form, $form_state));
+    }
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function submitForm(array &$form, FormStateInterface $form_state) {
+    parent::submitForm($form, $form_state);
+
+    $entity = $this->entity;
+    // The Block Entity form puts all block plugin form elements in the
+    // settings form element, so just pass that to the block for submission.
+    $sub_form_state = SubformState::createForSubform($form['settings'], $form, $form_state);
+    // Call the plugin submit handler.
+    $block = $entity->getPlugin();
+    $this->getPluginForm($block)->submitConfigurationForm($form, $sub_form_state);
+    // If this block is context-aware, set the context mapping.
+    if ($block instanceof ContextAwarePluginInterface && $block->getContextDefinitions()) {
+      $context_mapping = $sub_form_state->getValue('context_mapping', []);
+      $block->setContextMapping($context_mapping);
+    }
+
+    $this->submitVisibility($form, $form_state);
+
+    // Save the settings of the plugin.
+    $entity->save();
+
+    drupal_set_message($this->t('The block configuration has been saved.'));
+    $form_state->setRedirect(
+      'block.admin_display_theme',
+      array(
+        'theme' => $form_state->getValue('theme'),
+      ),
+      array('query' => array('block-placement' => Html::getClass($this->entity->id())))
+    );
+  }
+
+  /**
+   * Helper function to independently submit the visibility UI.
+   *
+   * @param array $form
+   *   A nested array form elements comprising the form.
+   * @param \Drupal\Core\Form\FormStateInterface $form_state
+   *   The current state of the form.
+   */
+  protected function submitVisibility(array $form, FormStateInterface $form_state) {
+    foreach ($form_state->getValue('visibility') as $condition_id => $values) {
+      // Allow the condition to submit the form.
+      $condition = $form_state->get(['conditions', $condition_id]);
+      $condition->submitConfigurationForm($form['visibility'][$condition_id], SubformState::createForSubform($form['visibility'][$condition_id], $form, $form_state));
+
+      // Setting conditions' context mappings is the plugins' responsibility.
+      // This code exists for backwards compatibility, because
+      // \Drupal\Core\Condition\ConditionPluginBase::submitConfigurationForm()
+      // did not set its own mappings until Drupal 8.2
+      // @todo Remove the code that sets context mappings in Drupal 9.0.0.
+      if ($condition instanceof ContextAwarePluginInterface) {
+        $context_mapping = isset($values['context_mapping']) ? $values['context_mapping'] : [];
+        $condition->setContextMapping($context_mapping);
+      }
+
+      $condition_configuration = $condition->getConfiguration();
+      // Update the visibility conditions on the block.
+      $this->entity->getVisibilityConditions()->addInstanceId($condition_id, $condition_configuration);
+    }
+  }
+
+  /**
+   * Generates a unique machine name for a block.
+   *
+   * @param \Drupal\block\BlockInterface $block
+   *   The block entity.
+   *
+   * @return string
+   *   Returns the unique name.
+   */
+  public function getUniqueMachineName(BlockInterface $block) {
+    $suggestion = $block->getPlugin()->getMachineNameSuggestion();
+
+    // Get all the blocks which starts with the suggested machine name.
+    $query = $this->storage->getQuery();
+    $query->condition('id', $suggestion, 'CONTAINS');
+    $block_ids = $query->execute();
+
+    $block_ids = array_map(function ($block_id) {
+      $parts = explode('.', $block_id);
+      return end($parts);
+    }, $block_ids);
+
+    // Iterate through potential IDs until we get a new one. E.g.
+    // 'plugin', 'plugin_2', 'plugin_3', etc.
+    $count = 1;
+    $machine_default = $suggestion;
+    while (in_array($machine_default, $block_ids)) {
+      $machine_default = $suggestion . '_' . ++$count;
+    }
+    return $machine_default;
+  }
+
+  /**
+   * Retrieves the plugin form for a given block and operation.
+   *
+   * @param \Drupal\Core\Block\BlockPluginInterface $block
+   *   The block plugin.
+   *
+   * @return \Drupal\Core\Plugin\PluginFormInterface
+   *   The plugin form for the block.
+   */
+  protected function getPluginForm(BlockPluginInterface $block) {
+    if ($block instanceof PluginWithFormsInterface) {
+      return $this->pluginFormFactory->createInstance($block, 'configure');
+    }
+    return $block;
+  }
+
+}

web/core/modules/block/src/BlockInterface.php

@@ -0,0 +1,135 @@
+<?php
+
+namespace Drupal\block;
+
+use Drupal\Core\Config\Entity\ConfigEntityInterface;
+
+/**
+ * Provides an interface defining a block entity.
+ */
+interface BlockInterface extends ConfigEntityInterface {
+
+  /**
+   * Indicates the block label (title) should be displayed to end users.
+   */
+  const BLOCK_LABEL_VISIBLE = 'visible';
+
+  /**
+   * Denotes that a block is not enabled in any region and should not be shown.
+   */
+  const BLOCK_REGION_NONE = -1;
+
+  /**
+   * Returns the plugin instance.
+   *
+   * @return \Drupal\Core\Block\BlockPluginInterface
+   *   The plugin instance for this block.
+   */
+  public function getPlugin();
+
+  /**
+   * Returns the plugin ID.
+   *
+   * @return string
+   *   The plugin ID for this block.
+   */
+  public function getPluginId();
+
+  /**
+   * Returns the region this block is placed in.
+   *
+   * @return string
+   *   The region this block is placed in.
+   */
+  public function getRegion();
+
+  /**
+   * Returns the theme ID.
+   *
+   * @return string
+   *   The theme ID for this block instance.
+   */
+  public function getTheme();
+
+  /**
+   * Returns an array of visibility condition configurations.
+   *
+   * @return array
+   *   An array of visibility condition configuration keyed by the condition ID.
+   */
+  public function getVisibility();
+
+  /**
+   * Gets conditions for this block.
+   *
+   * @return \Drupal\Core\Condition\ConditionInterface[]|\Drupal\Core\Condition\ConditionPluginCollection
+   *   An array or collection of configured condition plugins.
+   */
+  public function getVisibilityConditions();
+
+  /**
+   * Gets a visibility condition plugin instance.
+   *
+   * @param string $instance_id
+   *   The condition plugin instance ID.
+   *
+   * @return \Drupal\Core\Condition\ConditionInterface
+   *   A condition plugin.
+   */
+  public function getVisibilityCondition($instance_id);
+
+  /**
+   * Sets the visibility condition configuration.
+   *
+   * @param string $instance_id
+   *   The condition instance ID.
+   * @param array $configuration
+   *   The condition configuration.
+   *
+   * @return $this
+   */
+  public function setVisibilityConfig($instance_id, array $configuration);
+
+  /**
+   * Returns the weight of this block (used for sorting).
+   *
+   * @return int
+   *   The block weight.
+   */
+  public function getWeight();
+
+  /**
+   * Sets the region this block is placed in.
+   *
+   * @param string $region
+   *   The region to place this block in.
+   *
+   * @return $this
+   */
+  public function setRegion($region);
+
+  /**
+   * Sets the block weight.
+   *
+   * @param int $weight
+   *   The desired weight.
+   *
+   * @return $this
+   */
+  public function setWeight($weight);
+
+  /**
+   * Creates a duplicate of the block entity.
+   *
+   * @param string $new_id
+   *   (optional) The new ID on the duplicate block.
+   * @param string $new_theme
+   *   (optional) The theme on the duplicate block.
+   *
+   * @return static
+   *   A clone of $this with all identifiers unset, so saving it inserts a new
+   *   entity into the storage system.
+   */
+  public function createDuplicateBlock($new_id = NULL, $new_theme = NULL);
+
+}

web/core/modules/block/src/BlockListBuilder.php

@@ -0,0 +1,385 @@
+<?php
+
+namespace Drupal\block;
+
+use Drupal\Component\Utility\Html;
+use Drupal\Component\Serialization\Json;
+use Drupal\Core\Config\Entity\ConfigEntityListBuilder;
+use Drupal\Core\Entity\EntityInterface;
+use Drupal\Core\Entity\EntityStorageInterface;
+use Drupal\Core\Entity\EntityTypeInterface;
+use Drupal\Core\Form\FormBuilderInterface;
+use Drupal\Core\Form\FormInterface;
+use Drupal\Core\Form\FormStateInterface;
+use Drupal\Core\Theme\ThemeManagerInterface;
+use Drupal\Core\Url;
+use Symfony\Component\DependencyInjection\ContainerInterface;
+use Symfony\Component\HttpFoundation\Request;
+
+/**
+ * Defines a class to build a listing of block entities.
+ *
+ * @see \Drupal\block\Entity\Block
+ */
+class BlockListBuilder extends ConfigEntityListBuilder implements FormInterface {
+
+  /**
+   * The theme containing the blocks.
+   *
+   * @var string
+   */
+  protected $theme;
+
+  /**
+   * The current request.
+   *
+   * @var \Symfony\Component\HttpFoundation\Request
+   */
+  protected $request;
+
+  /**
+   * The theme manager.
+   *
+   * @var \Drupal\Core\Theme\ThemeManagerInterface
+   */
+  protected $themeManager;
+
+  /**
+   * The form builder.
+   *
+   * @var \Drupal\Core\Form\FormBuilderInterface
+   */
+  protected $formBuilder;
+
+  /**
+   * {@inheritdoc}
+   */
+  protected $limit = FALSE;
+
+  /**
+   * Constructs a new BlockListBuilder object.
+   *
+   * @param \Drupal\Core\Entity\EntityTypeInterface $entity_type
+   *   The entity type definition.
+   * @param \Drupal\Core\Entity\EntityStorageInterface $storage
+   *   The entity storage class.
+   * @param \Drupal\Core\Theme\ThemeManagerInterface $theme_manager
+   *   The theme manager.
+   * @param \Drupal\Core\Form\FormBuilderInterface $form_builder
+   *   The form builder.
+   */
+  public function __construct(EntityTypeInterface $entity_type, EntityStorageInterface $storage, ThemeManagerInterface $theme_manager, FormBuilderInterface $form_builder) {
+    parent::__construct($entity_type, $storage);
+
+    $this->themeManager = $theme_manager;
+    $this->formBuilder = $form_builder;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public static function createInstance(ContainerInterface $container, EntityTypeInterface $entity_type) {
+    return new static(
+      $entity_type,
+      $container->get('entity.manager')->getStorage($entity_type->id()),
+      $container->get('theme.manager'),
+      $container->get('form_builder')
+    );
+  }
+
+  /**
+   * {@inheritdoc}
+   *
+   * @param string|null $theme
+   *   (optional) The theme to display the blocks for. If NULL, the current
+   *   theme will be used.
+   * @param \Symfony\Component\HttpFoundation\Request $request
+   *   The current request.
+   *
+   * @return array
+   *   The block list as a renderable array.
+   */
+  public function render($theme = NULL, Request $request = NULL) {
+    $this->request = $request;
+    $this->theme = $theme;
+
+    return $this->formBuilder->getForm($this);
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function getFormId() {
+    return 'block_admin_display_form';
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function buildForm(array $form, FormStateInterface $form_state) {
+    $form['#attached']['library'][] = 'core/drupal.tableheader';
+    $form['#attached']['library'][] = 'block/drupal.block';
+    $form['#attached']['library'][] = 'block/drupal.block.admin';
+    $form['#attributes']['class'][] = 'clearfix';
+
+    // Build the form tree.
+    $form['blocks'] = $this->buildBlocksForm();
+
+    $form['actions'] = array(
+      '#tree' => FALSE,
+      '#type' => 'actions',
+    );
+    $form['actions']['submit'] = array(
+      '#type' => 'submit',
+      '#value' => $this->t('Save blocks'),
+      '#button_type' => 'primary',
+    );
+
+    return $form;
+  }
+
+  /**
+   * Builds the main "Blocks" portion of the form.
+   *
+   * @return array
+   */
+  protected function buildBlocksForm() {
+    // Build blocks first for each region.
+    $blocks = [];
+    $entities = $this->load();
+    /** @var \Drupal\block\BlockInterface[] $entities */
+    foreach ($entities as $entity_id => $entity) {
+      $definition = $entity->getPlugin()->getPluginDefinition();
+      $blocks[$entity->getRegion()][$entity_id] = array(
+        'label' => $entity->label(),
+        'entity_id' => $entity_id,
+        'weight' => $entity->getWeight(),
+        'entity' => $entity,
+        'category' => $definition['category'],
+      );
+    }
+
+    $form = array(
+      '#type' => 'table',
+      '#header' => array(
+        $this->t('Block'),
+        $this->t('Category'),
+        $this->t('Region'),
+        $this->t('Weight'),
+        $this->t('Operations'),
+      ),
+      '#attributes' => array(
+        'id' => 'blocks',
+      ),
+    );
+
+    // Weights range from -delta to +delta, so delta should be at least half
+    // of the amount of blocks present. This makes sure all blocks in the same
+    // region get an unique weight.
+    $weight_delta = round(count($entities) / 2);
+
+    $placement = FALSE;
+    if ($this->request->query->has('block-placement')) {
+      $placement = $this->request->query->get('block-placement');
+      $form['#attached']['drupalSettings']['blockPlacement'] = $placement;
+    }
+
+    // Loop over each region and build blocks.
+    $regions = $this->systemRegionList($this->getThemeName(), REGIONS_VISIBLE);
+    $block_regions_with_disabled = $regions + array(BlockInterface::BLOCK_REGION_NONE => $this->t('Disabled', array(), array('context' => 'Plural')));
+    foreach ($block_regions_with_disabled as $region => $title) {
+      $form['#tabledrag'][] = array(
+        'action' => 'match',
+        'relationship' => 'sibling',
+        'group' => 'block-region-select',
+        'subgroup' => 'block-region-' . $region,
+        'hidden' => FALSE,
+      );
+      $form['#tabledrag'][] = array(
+        'action' => 'order',
+        'relationship' => 'sibling',
+        'group' => 'block-weight',
+        'subgroup' => 'block-weight-' . $region,
+      );
+
+      $form['region-' . $region] = array(
+        '#attributes' => array(
+          'class' => array('region-title', 'region-title-' . $region),
+          'no_striping' => TRUE,
+        ),
+      );
+      $form['region-' . $region]['title'] = array(
+        '#theme_wrappers' => array(
+          'container' => array(
+            '#attributes' => array('class' => 'region-title__action'),
+          )
+        ),
+        '#prefix' => $region != BlockInterface::BLOCK_REGION_NONE ? $title : $block_regions_with_disabled[$region],
+        '#type' => 'link',
+        '#title' => $this->t('Place block <span class="visually-hidden">in the %region region</span>', ['%region' => $block_regions_with_disabled[$region]]),
+        '#url' => Url::fromRoute('block.admin_library', ['theme' => $this->getThemeName()], ['query' => ['region' => $region]]),
+        '#wrapper_attributes' => array(
+          'colspan' => 5,
+        ),
+        '#attributes' => [
+          'class' => ['use-ajax', 'button', 'button--small'],
+          'data-dialog-type' => 'modal',
+          'data-dialog-options' => Json::encode([
+            'width' => 700,
+          ]),
+        ],
+      );
+
+      $form['region-' . $region . '-message'] = array(
+        '#attributes' => array(
+          'class' => array(
+            'region-message',
+            'region-' . $region . '-message',
+            empty($blocks[$region]) ? 'region-empty' : 'region-populated',
+          ),
+        ),
+      );
+      $form['region-' . $region . '-message']['message'] = array(
+        '#markup' => '<em>' . $this->t('No blocks in this region') . '</em>',
+        '#wrapper_attributes' => array(
+          'colspan' => 5,
+        ),
+      );
+
+      if (isset($blocks[$region])) {
+        foreach ($blocks[$region] as $info) {
+          $entity_id = $info['entity_id'];
+
+          $form[$entity_id] = array(
+            '#attributes' => array(
+              'class' => array('draggable'),
+            ),
+          );
+          if ($placement && $placement == Html::getClass($entity_id)) {
+            $form[$entity_id]['#attributes']['class'][] = 'color-success';
+            $form[$entity_id]['#attributes']['class'][] = 'js-block-placed';
+          }
+          $form[$entity_id]['info'] = array(
+            '#plain_text' => $info['label'],
+            '#wrapper_attributes' => array(
+              'class' => array('block'),
+            ),
+          );
+          $form[$entity_id]['type'] = array(
+            '#markup' => $info['category'],
+          );
+          $form[$entity_id]['region-theme']['region'] = array(
+            '#type' => 'select',
+            '#default_value' => $region,
+            '#empty_value' => BlockInterface::BLOCK_REGION_NONE,
+            '#title' => $this->t('Region for @block block', array('@block' => $info['label'])),
+            '#title_display' => 'invisible',
+            '#options' => $regions,
+            '#attributes' => array(
+              'class' => array('block-region-select', 'block-region-' . $region),
+            ),
+            '#parents' => array('blocks', $entity_id, 'region'),
+          );
+          $form[$entity_id]['region-theme']['theme'] = array(
+            '#type' => 'hidden',
+            '#value' => $this->getThemeName(),
+            '#parents' => array('blocks', $entity_id, 'theme'),
+          );
+          $form[$entity_id]['weight'] = array(
+            '#type' => 'weight',
+            '#default_value' => $info['weight'],
+            '#delta' => $weight_delta,
+            '#title' => $this->t('Weight for @block block', array('@block' => $info['label'])),
+            '#title_display' => 'invisible',
+            '#attributes' => array(
+              'class' => array('block-weight', 'block-weight-' . $region),
+            ),
+          );
+          $form[$entity_id]['operations'] = $this->buildOperations($info['entity']);
+        }
+      }
+    }
+
+    // Do not allow disabling the main system content block when it is present.
+    if (isset($form['system_main']['region'])) {
+      $form['system_main']['region']['#required'] = TRUE;
+    }
+    return $form;
+  }
+
+  /**
+   * Gets the name of the theme used for this block listing.
+   *
+   * @return string
+   *   The name of the theme.
+   */
+  protected function getThemeName() {
+    // If no theme was specified, use the current theme.
+    if (!$this->theme) {
+      $this->theme = $this->themeManager->getActiveTheme()->getName();
+    }
+    return $this->theme;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  protected function getEntityIds() {
+    return $this->getStorage()->getQuery()
+      ->condition('theme', $this->getThemeName())
+      ->sort($this->entityType->getKey('id'))
+      ->execute();
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function getDefaultOperations(EntityInterface $entity) {
+    $operations = parent::getDefaultOperations($entity);
+
+    if (isset($operations['edit'])) {
+      $operations['edit']['title'] = $this->t('Configure');
+    }
+
+    return $operations;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function validateForm(array &$form, FormStateInterface $form_state) {
+    // No validation.
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function submitForm(array &$form, FormStateInterface $form_state) {
+    $entities = $this->storage->loadMultiple(array_keys($form_state->getValue('blocks')));
+    /** @var \Drupal\block\BlockInterface[] $entities */
+    foreach ($entities as $entity_id => $entity) {
+      $entity_values = $form_state->getValue(array('blocks', $entity_id));
+      $entity->setWeight($entity_values['weight']);
+      $entity->setRegion($entity_values['region']);
+      if ($entity->getRegion() == BlockInterface::BLOCK_REGION_NONE) {
+        $entity->disable();
+      }
+      else {
+        $entity->enable();
+      }
+      $entity->save();
+    }
+    drupal_set_message(t('The block settings have been updated.'));
+
+    // Remove any previously set block placement.
+    $this->request->query->remove('block-placement');
+  }
+
+  /**
+   * Wraps system_region_list().
+   */
+  protected function systemRegionList($theme, $show = REGIONS_ALL) {
+    return system_region_list($theme, $show);
+  }
+
+}

web/core/modules/block/src/BlockPluginCollection.php

@@ -0,0 +1,70 @@
+<?php
+
+namespace Drupal\block;
+
+use Drupal\Component\Plugin\Exception\PluginException;
+use Drupal\Component\Plugin\PluginManagerInterface;
+use Drupal\Core\Plugin\DefaultSingleLazyPluginCollection;
+
+/**
+ * Provides a collection of block plugins.
+ */
+class BlockPluginCollection extends DefaultSingleLazyPluginCollection {
+
+  /**
+   * The block ID this plugin collection belongs to.
+   *
+   * @var string
+   */
+  protected $blockId;
+
+  /**
+   * Constructs a new BlockPluginCollection.
+   *
+   * @param \Drupal\Component\Plugin\PluginManagerInterface $manager
+   *   The manager to be used for instantiating plugins.
+   * @param string $instance_id
+   *   The ID of the plugin instance.
+   * @param array $configuration
+   *   An array of configuration.
+   * @param string $block_id
+   *   The unique ID of the block entity using this plugin.
+   */
+  public function __construct(PluginManagerInterface $manager, $instance_id, array $configuration, $block_id) {
+    parent::__construct($manager, $instance_id, $configuration);
+
+    $this->blockId = $block_id;
+  }
+
+  /**
+   * {@inheritdoc}
+   *
+   * @return \Drupal\Core\Block\BlockPluginInterface
+   */
+  public function &get($instance_id) {
+    return parent::get($instance_id);
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  protected function initializePlugin($instance_id) {
+    if (!$instance_id) {
+      throw new PluginException("The block '{$this->blockId}' did not specify a plugin.");
+    }
+
+    try {
+      parent::initializePlugin($instance_id);
+    }
+    catch (PluginException $e) {
+      $module = $this->configuration['provider'];
+      // Ignore blocks belonging to uninstalled modules, but re-throw valid
+      // exceptions when the module is installed and the plugin is
+      // misconfigured.
+      if (!$module || \Drupal::moduleHandler()->moduleExists($module)) {
+        throw $e;
+      }
+    }
+  }
+
+}

web/core/modules/block/src/BlockRepository.php

@@ -0,0 +1,81 @@
+<?php
+
+namespace Drupal\block;
+
+use Drupal\Core\Cache\CacheableMetadata;
+use Drupal\Core\Entity\EntityManagerInterface;
+use Drupal\Core\Plugin\Context\ContextHandlerInterface;
+use Drupal\Core\Theme\ThemeManagerInterface;
+
+/**
+ * Provides a repository for Block config entities.
+ */
+class BlockRepository implements BlockRepositoryInterface {
+
+  /**
+   * The block storage.
+   *
+   * @var \Drupal\Core\Entity\EntityStorageInterface
+   */
+  protected $blockStorage;
+
+  /**
+   * The theme manager.
+   *
+   * @var \Drupal\Core\Theme\ThemeManagerInterface
+   */
+  protected $themeManager;
+
+  /**
+   * Constructs a new BlockRepository.
+   *
+   * @param \Drupal\Core\Entity\EntityManagerInterface $entity_manager
+   *   The entity manager.
+   * @param \Drupal\Core\Theme\ThemeManagerInterface $theme_manager
+   *   The theme manager.
+   * @param \Drupal\Core\Plugin\Context\ContextHandlerInterface $context_handler
+   *   The plugin context handler.
+   */
+  public function __construct(EntityManagerInterface $entity_manager, ThemeManagerInterface $theme_manager, ContextHandlerInterface $context_handler) {
+    $this->blockStorage = $entity_manager->getStorage('block');
+    $this->themeManager = $theme_manager;
+    $this->contextHandler = $context_handler;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function getVisibleBlocksPerRegion(array &$cacheable_metadata = []) {
+    $active_theme = $this->themeManager->getActiveTheme();
+    // Build an array of the region names in the right order.
+    $empty = array_fill_keys($active_theme->getRegions(), array());
+
+    $full = array();
+    foreach ($this->blockStorage->loadByProperties(array('theme' => $active_theme->getName())) as $block_id => $block) {
+      /** @var \Drupal\block\BlockInterface $block */
+      $access = $block->access('view', NULL, TRUE);
+      $region = $block->getRegion();
+      if (!isset($cacheable_metadata[$region])) {
+        $cacheable_metadata[$region] = CacheableMetadata::createFromObject($access);
+      }
+      else {
+        $cacheable_metadata[$region] = $cacheable_metadata[$region]->merge(CacheableMetadata::createFromObject($access));
+      }
+
+      // Set the contexts on the block before checking access.
+      if ($access->isAllowed()) {
+        $full[$region][$block_id] = $block;
+      }
+    }
+
+    // Merge it with the actual values to maintain the region ordering.
+    $assignments = array_intersect_key(array_merge($empty, $full), $empty);
+    foreach ($assignments as &$assignment) {
+      // Suppress errors because PHPUnit will indirectly modify the contents,
+      // triggering https://bugs.php.net/bug.php?id=50688.
+      @uasort($assignment, 'Drupal\block\Entity\Block::sort');
+    }
+    return $assignments;
+  }
+
+}

web/core/modules/block/src/BlockRepositoryInterface.php

@@ -0,0 +1,20 @@
+<?php
+
+namespace Drupal\block;
+
+interface BlockRepositoryInterface {
+
+  /**
+   * Returns an array of regions and their block entities.
+   *
+   * @param \Drupal\Core\Cache\CacheableMetadata[] $cacheable_metadata
+   *   (optional) List of CacheableMetadata objects, keyed by region. This is
+   *   by reference and is used to pass this information back to the caller.
+   *
+   * @return array
+   *   The array is first keyed by region machine name, with the values
+   *   containing an array keyed by block ID, with block entities as the values.
+   */
+  public function getVisibleBlocksPerRegion(array &$cacheable_metadata = []);
+
+}

web/core/modules/block/src/BlockViewBuilder.php

@@ -0,0 +1,251 @@
+<?php
+
+namespace Drupal\block;
+
+use Drupal\Core\Block\MainContentBlockPluginInterface;
+use Drupal\Core\Block\TitleBlockPluginInterface;
+use Drupal\Core\Cache\Cache;
+use Drupal\Core\Cache\CacheableMetadata;
+use Drupal\Core\Entity\EntityManagerInterface;
+use Drupal\Core\Entity\EntityTypeInterface;
+use Drupal\Core\Entity\EntityViewBuilder;
+use Drupal\Core\Entity\EntityInterface;
+use Drupal\Core\Extension\ModuleHandlerInterface;
+use Drupal\Core\Language\LanguageManagerInterface;
+use Drupal\Core\Plugin\ContextAwarePluginInterface;
+use Drupal\Core\Render\Element;
+use Drupal\block\Entity\Block;
+use Symfony\Component\DependencyInjection\ContainerInterface;
+
+/**
+ * Provides a Block view builder.
+ */
+class BlockViewBuilder extends EntityViewBuilder {
+
+  /**
+   * The module handler.
+   *
+   * @var \Drupal\Core\Extension\ModuleHandlerInterface
+   */
+  protected $moduleHandler;
+
+  /**
+   * Constructs a new BlockViewBuilder.
+   *
+   * @param \Drupal\Core\Entity\EntityTypeInterface $entity_type
+   *   The entity type definition.
+   * @param \Drupal\Core\Entity\EntityManagerInterface $entity_manager
+   *   The entity manager service.
+   * @param \Drupal\Core\Language\LanguageManagerInterface $language_manager
+   *   The language manager.
+   * @param \Drupal\Core\Extension\ModuleHandlerInterface $module_handler
+   *   The module handler.
+   */
+  public function __construct(EntityTypeInterface $entity_type, EntityManagerInterface $entity_manager, LanguageManagerInterface $language_manager, ModuleHandlerInterface $module_handler) {
+    parent::__construct($entity_type, $entity_manager, $language_manager);
+    $this->moduleHandler = $module_handler;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public static function createInstance(ContainerInterface $container, EntityTypeInterface $entity_type) {
+    return new static(
+      $entity_type,
+      $container->get('entity.manager'),
+      $container->get('language_manager'),
+      $container->get('module_handler')
+    );
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function buildComponents(array &$build, array $entities, array $displays, $view_mode) {
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function view(EntityInterface $entity, $view_mode = 'full', $langcode = NULL) {
+    $build = $this->viewMultiple(array($entity), $view_mode, $langcode);
+    return reset($build);
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function viewMultiple(array $entities = array(), $view_mode = 'full', $langcode = NULL) {
+    /** @var \Drupal\block\BlockInterface[] $entities */
+    $build = array();
+    foreach ($entities as $entity) {
+      $entity_id = $entity->id();
+      $plugin = $entity->getPlugin();
+
+      $cache_tags = Cache::mergeTags($this->getCacheTags(), $entity->getCacheTags());
+      $cache_tags = Cache::mergeTags($cache_tags, $plugin->getCacheTags());
+
+      // Create the render array for the block as a whole.
+      // @see template_preprocess_block().
+      $build[$entity_id] = array(
+        '#cache' => [
+          'keys' => ['entity_view', 'block', $entity->id()],
+          'contexts' => Cache::mergeContexts(
+            $entity->getCacheContexts(),
+            $plugin->getCacheContexts()
+          ),
+          'tags' => $cache_tags,
+          'max-age' => $plugin->getCacheMaxAge(),
+        ],
+        '#weight' => $entity->getWeight(),
+      );
+
+      // Allow altering of cacheability metadata or setting #create_placeholder.
+      $this->moduleHandler->alter(['block_build', "block_build_" . $plugin->getBaseId()], $build[$entity_id], $plugin);
+
+      if ($plugin instanceof MainContentBlockPluginInterface || $plugin instanceof TitleBlockPluginInterface) {
+        // Immediately build a #pre_render-able block, since this block cannot
+        // be built lazily.
+        $build[$entity_id] += static::buildPreRenderableBlock($entity, $this->moduleHandler());
+      }
+      else {
+        // Assign a #lazy_builder callback, which will generate a #pre_render-
+        // able block lazily (when necessary).
+        $build[$entity_id] += [
+          '#lazy_builder' => [static::class . '::lazyBuilder', [$entity_id, $view_mode, $langcode]],
+        ];
+      }
+    }
+
+    return $build;
+  }
+
+  /**
+   * Builds a #pre_render-able block render array.
+   *
+   * @param \Drupal\block\BlockInterface $entity
+   *   A block config entity.
+   * @param \Drupal\Core\Extension\ModuleHandlerInterface $module_handler
+   *   The module handler service.
+   *
+   * @return array
+   *   A render array with a #pre_render callback to render the block.
+   */
+  protected static function buildPreRenderableBlock($entity, ModuleHandlerInterface $module_handler) {
+    $plugin = $entity->getPlugin();
+    $plugin_id = $plugin->getPluginId();
+    $base_id = $plugin->getBaseId();
+    $derivative_id = $plugin->getDerivativeId();
+    $configuration = $plugin->getConfiguration();
+
+    // Inject runtime contexts.
+    if ($plugin instanceof ContextAwarePluginInterface) {
+      $contexts = \Drupal::service('context.repository')->getRuntimeContexts($plugin->getContextMapping());
+      \Drupal::service('context.handler')->applyContextMapping($plugin, $contexts);
+    }
+
+    // Create the render array for the block as a whole.
+    // @see template_preprocess_block().
+    $build = [
+      '#theme' => 'block',
+      '#attributes' => [],
+      // All blocks get a "Configure block" contextual link.
+      '#contextual_links' => [
+        'block' => [
+          'route_parameters' => ['block' => $entity->id()],
+        ],
+      ],
+      '#weight' => $entity->getWeight(),
+      '#configuration' => $configuration,
+      '#plugin_id' => $plugin_id,
+      '#base_plugin_id' => $base_id,
+      '#derivative_plugin_id' => $derivative_id,
+      '#id' => $entity->id(),
+      '#pre_render' => [
+        static::class . '::preRender',
+      ],
+      // Add the entity so that it can be used in the #pre_render method.
+      '#block' => $entity,
+    ];
+
+    // If an alter hook wants to modify the block contents, it can append
+    // another #pre_render hook.
+    $module_handler->alter(['block_view', "block_view_$base_id"], $build, $plugin);
+
+    return $build;
+  }
+
+  /**
+   * #lazy_builder callback; builds a #pre_render-able block.
+   *
+   * @param $entity_id
+   *   A block config entity ID.
+   * @param $view_mode
+   *   The view mode the block is being viewed in.
+   *
+   * @return array
+   *   A render array with a #pre_render callback to render the block.
+   */
+  public static function lazyBuilder($entity_id, $view_mode) {
+    return static::buildPreRenderableBlock(Block::load($entity_id), \Drupal::service('module_handler'));
+  }
+
+  /**
+   * #pre_render callback for building a block.
+   *
+   * Renders the content using the provided block plugin, and then:
+   * - if there is no content, aborts rendering, and makes sure the block won't
+   *   be rendered.
+   * - if there is content, moves the contextual links from the block content to
+   *   the block itself.
+   */
+  public static function preRender($build) {
+    $content = $build['#block']->getPlugin()->build();
+    // Remove the block entity from the render array, to ensure that blocks
+    // can be rendered without the block config entity.
+    unset($build['#block']);
+    if ($content !== NULL && !Element::isEmpty($content)) {
+      // Place the $content returned by the block plugin into a 'content' child
+      // element, as a way to allow the plugin to have complete control of its
+      // properties and rendering (for instance, its own #theme) without
+      // conflicting with the properties used above, or alternate ones used by
+      // alternate block rendering approaches in contrib (for instance, Panels).
+      // However, the use of a child element is an implementation detail of this
+      // particular block rendering approach. Semantically, the content returned
+      // by the plugin "is the" block, and in particular, #attributes and
+      // #contextual_links is information about the *entire* block. Therefore,
+      // we must move these properties from $content and merge them into the
+      // top-level element.
+      foreach (array('#attributes', '#contextual_links') as $property) {
+        if (isset($content[$property])) {
+          $build[$property] += $content[$property];
+          unset($content[$property]);
+        }
+      }
+      $build['content'] = $content;
+    }
+    // Either the block's content is completely empty, or it consists only of
+    // cacheability metadata.
+    else {
+      // Abort rendering: render as the empty string and ensure this block is
+      // render cached, so we can avoid the work of having to repeatedly
+      // determine whether the block is empty. For instance, modifying or adding
+      // entities could cause the block to no longer be empty.
+      $build = array(
+        '#markup' => '',
+        '#cache' => $build['#cache'],
+      );
+      // If $content is not empty, then it contains cacheability metadata, and
+      // we must merge it with the existing cacheability metadata. This allows
+      // blocks to be empty, yet still bubble cacheability metadata, to indicate
+      // why they are empty.
+      if (!empty($content)) {
+        CacheableMetadata::createFromRenderArray($build)
+          ->merge(CacheableMetadata::createFromRenderArray($content))
+          ->applyTo($build);
+      }
+    }
+    return $build;
+  }
+
+}

web/core/modules/block/src/Controller/BlockAddController.php

@@ -0,0 +1,30 @@
+<?php
+
+namespace Drupal\block\Controller;
+
+use Drupal\Core\Controller\ControllerBase;
+
+/**
+ * Controller for building the block instance add form.
+ */
+class BlockAddController extends ControllerBase {
+
+  /**
+   * Build the block instance add form.
+   *
+   * @param string $plugin_id
+   *   The plugin ID for the block instance.
+   * @param string $theme
+   *   The name of the theme for the block instance.
+   *
+   * @return array
+   *   The block instance edit form.
+   */
+  public function blockAddConfigureForm($plugin_id, $theme) {
+    // Create a block entity.
+    $entity = $this->entityManager()->getStorage('block')->create(array('plugin' => $plugin_id, 'theme' => $theme));
+
+    return $this->entityFormBuilder()->getForm($entity);
+  }
+
+}

web/core/modules/block/src/Controller/BlockController.php

@@ -0,0 +1,100 @@
+<?php
+
+namespace Drupal\block\Controller;
+
+use Drupal\Component\Utility\Html;
+use Drupal\Core\Controller\ControllerBase;
+use Drupal\Core\Extension\ThemeHandlerInterface;
+use Symfony\Component\DependencyInjection\ContainerInterface;
+use Symfony\Component\HttpKernel\Exception\NotFoundHttpException;
+
+/**
+ * Controller routines for admin block routes.
+ */
+class BlockController extends ControllerBase {
+
+  /**
+   * The theme handler.
+   *
+   * @var \Drupal\Core\Extension\ThemeHandlerInterface
+   */
+  protected $themeHandler;
+
+  /**
+   * Constructs a new BlockController instance.
+   *
+   * @param \Drupal\Core\Extension\ThemeHandlerInterface $theme_handler
+   *   The theme handler.
+   */
+  public function __construct(ThemeHandlerInterface $theme_handler) {
+    $this->themeHandler = $theme_handler;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public static function create(ContainerInterface $container) {
+    return new static(
+      $container->get('theme_handler')
+    );
+  }
+
+  /**
+   * Returns a block theme demo page.
+   *
+   * @param string $theme
+   *   The name of the theme.
+   *
+   * @return array
+   *   A #type 'page' render array containing the block region demo.
+   */
+  public function demo($theme) {
+    if (!$this->themeHandler->hasUi($theme)) {
+      throw new NotFoundHttpException();
+    }
+
+    $page = [
+      '#title' => Html::escape($this->themeHandler->getName($theme)),
+      '#type' => 'page',
+      '#attached' => array(
+        'drupalSettings' => [
+          // The block demonstration page is not marked as an administrative
+          // page by \Drupal::service('router.admin_context')->isAdminRoute()
+          // function in order to use the frontend theme. Since JavaScript
+          // relies on a proper separation of admin pages, it needs to know this
+          // is an actual administrative page.
+          'path' => ['currentPathIsAdmin' => TRUE],
+        ],
+        'library' => array(
+          'block/drupal.block.admin',
+        ),
+      ),
+    ];
+
+    // Show descriptions in each visible page region, nothing else.
+    $visible_regions = $this->getVisibleRegionNames($theme);
+    foreach (array_keys($visible_regions) as $region) {
+      $page[$region]['block_description'] = array(
+        '#type' => 'inline_template',
+        '#template' => '<div class="block-region demo-block">{{ region_name }}</div>',
+        '#context' => array('region_name' => $visible_regions[$region]),
+      );
+    }
+
+    return $page;
+  }
+
+  /**
+   * Returns the human-readable list of regions keyed by machine name.
+   *
+   * @param string $theme
+   *   The name of the theme.
+   *
+   * @return array
+   *   An array of human-readable region names keyed by machine name.
+   */
+  protected function getVisibleRegionNames($theme) {
+    return system_region_list($theme, REGIONS_VISIBLE);
+  }
+
+}

web/core/modules/block/src/Controller/BlockLibraryController.php

@@ -0,0 +1,191 @@
+<?php
+
+namespace Drupal\block\Controller;
+
+use Drupal\Component\Serialization\Json;
+use Drupal\Core\Block\BlockManagerInterface;
+use Drupal\Core\Controller\ControllerBase;
+use Drupal\Core\EventSubscriber\MainContentViewSubscriber;
+use Drupal\Core\Menu\LocalActionManagerInterface;
+use Drupal\Core\Plugin\Context\LazyContextRepository;
+use Drupal\Core\Routing\RouteMatchInterface;
+use Drupal\Core\Url;
+use Symfony\Component\DependencyInjection\ContainerInterface;
+use Symfony\Component\HttpFoundation\Request;
+
+/**
+ * Provides a list of block plugins to be added to the layout.
+ */
+class BlockLibraryController extends ControllerBase {
+
+  /**
+   * The block manager.
+   *
+   * @var \Drupal\Core\Block\BlockManagerInterface
+   */
+  protected $blockManager;
+
+  /**
+   * The context repository.
+   *
+   * @var \Drupal\Core\Plugin\Context\LazyContextRepository
+   */
+  protected $contextRepository;
+
+  /**
+   * The route match.
+   *
+   * @var \Drupal\Core\Routing\RouteMatchInterface
+   */
+  protected $routeMatch;
+
+  /**
+   * The local action manager.
+   *
+   * @var \Drupal\Core\Menu\LocalActionManagerInterface
+   */
+  protected $localActionManager;
+
+  /**
+   * Constructs a BlockLibraryController object.
+   *
+   * @param \Drupal\Core\Block\BlockManagerInterface $block_manager
+   *   The block manager.
+   * @param \Drupal\Core\Plugin\Context\LazyContextRepository $context_repository
+   *   The context repository.
+   * @param \Drupal\Core\Routing\RouteMatchInterface $route_match
+   *   The current route match.
+   * @param \Drupal\Core\Menu\LocalActionManagerInterface $local_action_manager
+   *   The local action manager.
+   */
+  public function __construct(BlockManagerInterface $block_manager, LazyContextRepository $context_repository, RouteMatchInterface $route_match, LocalActionManagerInterface $local_action_manager) {
+    $this->blockManager = $block_manager;
+    $this->routeMatch = $route_match;
+    $this->localActionManager = $local_action_manager;
+    $this->contextRepository = $context_repository;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public static function create(ContainerInterface $container) {
+    return new static(
+      $container->get('plugin.manager.block'),
+      $container->get('context.repository'),
+      $container->get('current_route_match'),
+      $container->get('plugin.manager.menu.local_action')
+    );
+  }
+
+  /**
+   * Shows a list of blocks that can be added to a theme's layout.
+   *
+   * @param \Symfony\Component\HttpFoundation\Request $request
+   *   The current request.
+   * @param string $theme
+   *   Theme key of the block list.
+   *
+   * @return array
+   *   A render array as expected by the renderer.
+   */
+  public function listBlocks(Request $request, $theme) {
+    // Since modals do not render any other part of the page, we need to render
+    // them manually as part of this listing.
+    if ($request->query->get(MainContentViewSubscriber::WRAPPER_FORMAT) === 'drupal_modal') {
+      $build['local_actions'] = $this->buildLocalActions();
+    }
+
+    $headers = [
+      ['data' => $this->t('Block')],
+      ['data' => $this->t('Category')],
+      ['data' => $this->t('Operations')],
+    ];
+
+    // Only add blocks which work without any available context.
+    $definitions = $this->blockManager->getDefinitionsForContexts($this->contextRepository->getAvailableContexts());
+    // Order by category, and then by admin label.
+    $definitions = $this->blockManager->getSortedDefinitions($definitions);
+
+    $region = $request->query->get('region');
+    $weight = $request->query->get('weight');
+    $rows = [];
+    foreach ($definitions as $plugin_id => $plugin_definition) {
+      $row = [];
+      $row['title']['data'] = [
+        '#type' => 'inline_template',
+        '#template' => '<div class="block-filter-text-source">{{ label }}</div>',
+        '#context' => [
+          'label' => $plugin_definition['admin_label'],
+        ],
+      ];
+      $row['category']['data'] = $plugin_definition['category'];
+      $links['add'] = [
+        'title' => $this->t('Place block'),
+        'url' => Url::fromRoute('block.admin_add', ['plugin_id' => $plugin_id, 'theme' => $theme]),
+        'attributes' => [
+          'class' => ['use-ajax'],
+          'data-dialog-type' => 'modal',
+          'data-dialog-options' => Json::encode([
+            'width' => 700,
+          ]),
+        ],
+      ];
+      if ($region) {
+        $links['add']['query']['region'] = $region;
+      }
+      if (isset($weight)) {
+        $links['add']['query']['weight'] = $weight;
+      }
+      $row['operations']['data'] = [
+        '#type' => 'operations',
+        '#links' => $links,
+      ];
+      $rows[] = $row;
+    }
+
+    $build['#attached']['library'][] = 'block/drupal.block.admin';
+
+    $build['filter'] = [
+      '#type' => 'search',
+      '#title' => $this->t('Filter'),
+      '#title_display' => 'invisible',
+      '#size' => 30,
+      '#placeholder' => $this->t('Filter by block name'),
+      '#attributes' => [
+        'class' => ['block-filter-text'],
+        'data-element' => '.block-add-table',
+        'title' => $this->t('Enter a part of the block name to filter by.'),
+      ],
+    ];
+
+    $build['blocks'] = [
+      '#type' => 'table',
+      '#header' => $headers,
+      '#rows' => $rows,
+      '#empty' => $this->t('No blocks available.'),
+      '#attributes' => [
+        'class' => ['block-add-table'],
+      ],
+    ];
+
+    return $build;
+  }
+
+  /**
+   * Builds the local actions for this listing.
+   *
+   * @return array
+   *   An array of local actions for this listing.
+   */
+  protected function buildLocalActions() {
+    $build = $this->localActionManager->getActionsForRoute($this->routeMatch->getRouteName());
+    // Without this workaround, the action links will be rendered as <li> with
+    // no wrapping <ul> element.
+    if (!empty($build)) {
+      $build['#prefix'] = '<ul class="action-links">';
+      $build['#suffix'] = '</ul>';
+    }
+    return $build;
+  }
+
+}

web/core/modules/block/src/Controller/BlockListController.php

@@ -0,0 +1,62 @@
+<?php
+
+namespace Drupal\block\Controller;
+
+use Drupal\Core\Entity\Controller\EntityListController;
+use Drupal\Core\Extension\ThemeHandlerInterface;
+use Symfony\Component\DependencyInjection\ContainerInterface;
+use Symfony\Component\HttpFoundation\Request;
+use Symfony\Component\HttpKernel\Exception\NotFoundHttpException;
+
+/**
+ * Defines a controller to list blocks.
+ */
+class BlockListController extends EntityListController {
+
+  /**
+   * The theme handler.
+   *
+   * @var \Drupal\Core\Extension\ThemeHandlerInterface
+   */
+  protected $themeHandler;
+
+  /**
+   * Constructs the BlockListController.
+   *
+   * @param \Drupal\Core\Extension\ThemeHandlerInterface $theme_handler
+   *   The theme handler.
+   */
+  public function __construct(ThemeHandlerInterface $theme_handler) {
+    $this->themeHandler = $theme_handler;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public static function create(ContainerInterface $container) {
+    return new static(
+      $container->get('theme_handler')
+    );
+  }
+
+  /**
+   * Shows the block administration page.
+   *
+   * @param string|null $theme
+   *   Theme key of block list.
+   * @param \Symfony\Component\HttpFoundation\Request $request
+   *   The current request.
+   *
+   * @return array
+   *   A render array as expected by drupal_render().
+   */
+  public function listing($theme = NULL, Request $request = NULL) {
+    $theme = $theme ?: $this->config('system.theme')->get('default');
+    if (!$this->themeHandler->hasUi($theme)) {
+      throw new NotFoundHttpException();
+    }
+
+    return $this->entityManager()->getListBuilder('block')->render($theme, $request);
+  }
+
+}

web/core/modules/block/src/Controller/CategoryAutocompleteController.php

@@ -0,0 +1,63 @@
+<?php
+
+namespace Drupal\block\Controller;
+
+use Drupal\Component\Utility\Html;
+use Drupal\Core\Block\BlockManagerInterface;
+use Drupal\Core\DependencyInjection\ContainerInjectionInterface;
+use Symfony\Component\DependencyInjection\ContainerInterface;
+use Symfony\Component\HttpFoundation\JsonResponse;
+use Symfony\Component\HttpFoundation\Request;
+
+/**
+ * Returns autocomplete responses for block categories.
+ */
+class CategoryAutocompleteController implements ContainerInjectionInterface {
+
+  /**
+   * The block manager.
+   *
+   * @var \Drupal\Core\Block\BlockManagerInterface
+   */
+  protected $blockManager;
+
+  /**
+   * Constructs a new CategoryAutocompleteController.
+   *
+   * @param \Drupal\Core\Block\BlockManagerInterface $block_manager
+   *   The block manager.
+   */
+  public function __construct(BlockManagerInterface $block_manager) {
+    $this->blockManager = $block_manager;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public static function create(ContainerInterface $container) {
+    return new static(
+      $container->get('plugin.manager.block')
+    );
+  }
+
+  /**
+   * Retrieves suggestions for block category autocompletion.
+   *
+   * @param \Symfony\Component\HttpFoundation\Request $request
+   *   The current request.
+   *
+   * @return \Symfony\Component\HttpFoundation\JsonResponse
+   *   A JSON response containing autocomplete suggestions.
+   */
+  public function autocomplete(Request $request) {
+    $typed_category = $request->query->get('q');
+    $matches = array();
+    foreach ($this->blockManager->getCategories() as $category) {
+      if (stripos($category, $typed_category) === 0) {
+        $matches[] = array('value' => $category, 'label' => Html::escape($category));
+      }
+    }
+    return new JsonResponse($matches);
+  }
+
+}

web/core/modules/block/src/Entity/Block.php

@@ -0,0 +1,330 @@
+<?php
+
+namespace Drupal\block\Entity;
+
+use Drupal\Core\Cache\Cache;
+use Drupal\Core\Condition\ConditionPluginCollection;
+use Drupal\Core\Config\Entity\ConfigEntityBase;
+use Drupal\block\BlockPluginCollection;
+use Drupal\block\BlockInterface;
+use Drupal\Core\Config\Entity\ConfigEntityInterface;
+use Drupal\Core\Entity\EntityWithPluginCollectionInterface;
+use Drupal\Core\Entity\EntityStorageInterface;
+
+/**
+ * Defines a Block configuration entity class.
+ *
+ * @ConfigEntityType(
+ *   id = "block",
+ *   label = @Translation("Block"),
+ *   handlers = {
+ *     "access" = "Drupal\block\BlockAccessControlHandler",
+ *     "view_builder" = "Drupal\block\BlockViewBuilder",
+ *     "list_builder" = "Drupal\block\BlockListBuilder",
+ *     "form" = {
+ *       "default" = "Drupal\block\BlockForm",
+ *       "delete" = "Drupal\block\Form\BlockDeleteForm"
+ *     }
+ *   },
+ *   admin_permission = "administer blocks",
+ *   entity_keys = {
+ *     "id" = "id"
+ *   },
+ *   links = {
+ *     "delete-form" = "/admin/structure/block/manage/{block}/delete",
+ *     "edit-form" = "/admin/structure/block/manage/{block}"
+ *   },
+ *   config_export = {
+ *     "id",
+ *     "theme",
+ *     "region",
+ *     "weight",
+ *     "provider",
+ *     "plugin",
+ *     "settings",
+ *     "visibility",
+ *   },
+ *   lookup_keys = {
+ *     "theme"
+ *   }
+ * )
+ */
+class Block extends ConfigEntityBase implements BlockInterface, EntityWithPluginCollectionInterface {
+
+  /**
+   * The ID of the block.
+   *
+   * @var string
+   */
+  protected $id;
+
+  /**
+   * The plugin instance settings.
+   *
+   * @var array
+   */
+  protected $settings = array();
+
+  /**
+   * The region this block is placed in.
+   *
+   * @var string
+   */
+  protected $region = self::BLOCK_REGION_NONE;
+
+  /**
+   * The block weight.
+   *
+   * @var int
+   */
+  protected $weight;
+
+  /**
+   * The plugin instance ID.
+   *
+   * @var string
+   */
+  protected $plugin;
+
+  /**
+   * The visibility settings for this block.
+   *
+   * @var array
+   */
+  protected $visibility = [];
+
+  /**
+   * The plugin collection that holds the block plugin for this entity.
+   *
+   * @var \Drupal\block\BlockPluginCollection
+   */
+  protected $pluginCollection;
+
+  /**
+   * The available contexts for this block and its visibility conditions.
+   *
+   * @var array
+   */
+  protected $contexts = [];
+
+  /**
+   * The visibility collection.
+   *
+   * @var \Drupal\Core\Condition\ConditionPluginCollection
+   */
+  protected $visibilityCollection;
+
+  /**
+   * The condition plugin manager.
+   *
+   * @var \Drupal\Core\Executable\ExecutableManagerInterface
+   */
+  protected $conditionPluginManager;
+
+  /**
+   * The theme that includes the block plugin for this entity.
+   *
+   * @var string
+   */
+  protected $theme;
+
+  /**
+   * {@inheritdoc}
+   */
+  public function getPlugin() {
+    return $this->getPluginCollection()->get($this->plugin);
+  }
+
+  /**
+   * Encapsulates the creation of the block's LazyPluginCollection.
+   *
+   * @return \Drupal\Component\Plugin\LazyPluginCollection
+   *   The block's plugin collection.
+   */
+  protected function getPluginCollection() {
+    if (!$this->pluginCollection) {
+      $this->pluginCollection = new BlockPluginCollection(\Drupal::service('plugin.manager.block'), $this->plugin, $this->get('settings'), $this->id());
+    }
+    return $this->pluginCollection;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function getPluginCollections() {
+    return [
+      'settings' => $this->getPluginCollection(),
+      'visibility' => $this->getVisibilityConditions(),
+    ];
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function getPluginId() {
+    return $this->plugin;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function getRegion() {
+    return $this->region;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function getTheme() {
+    return $this->theme;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function getWeight() {
+    return $this->weight;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function label() {
+    $settings = $this->get('settings');
+    if ($settings['label']) {
+      return $settings['label'];
+    }
+    else {
+      $definition = $this->getPlugin()->getPluginDefinition();
+      return $definition['admin_label'];
+    }
+  }
+
+  /**
+   * Sorts active blocks by weight; sorts inactive blocks by name.
+   */
+  public static function sort(ConfigEntityInterface $a, ConfigEntityInterface $b) {
+    // Separate enabled from disabled.
+    $status = (int) $b->status() - (int) $a->status();
+    if ($status !== 0) {
+      return $status;
+    }
+    // Sort by weight, unless disabled.
+    if ($a->getRegion() != static::BLOCK_REGION_NONE) {
+      $weight = $a->getWeight() - $b->getWeight();
+      if ($weight) {
+        return $weight;
+      }
+    }
+    // Sort by label.
+    return strcmp($a->label(), $b->label());
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function calculateDependencies() {
+    parent::calculateDependencies();
+    $this->addDependency('theme', $this->theme);
+    return $this;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function postSave(EntityStorageInterface $storage, $update = TRUE) {
+    parent::postSave($storage, $update);
+
+    // Entity::postSave() calls Entity::invalidateTagsOnSave(), which only
+    // handles the regular cases. The Block entity has one special case: a
+    // newly created block may *also* appear on any page in the current theme,
+    // so we must invalidate the associated block's cache tag (which includes
+    // the theme cache tag).
+    if (!$update) {
+      Cache::invalidateTags($this->getCacheTagsToInvalidate());
+    }
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function getVisibility() {
+    return $this->getVisibilityConditions()->getConfiguration();
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function setVisibilityConfig($instance_id, array $configuration) {
+    $conditions = $this->getVisibilityConditions();
+    if (!$conditions->has($instance_id)) {
+      $configuration['id'] = $instance_id;
+      $conditions->addInstanceId($instance_id, $configuration);
+    }
+    else {
+      $conditions->setInstanceConfiguration($instance_id, $configuration);
+    }
+    return $this;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function getVisibilityConditions() {
+    if (!isset($this->visibilityCollection)) {
+      $this->visibilityCollection = new ConditionPluginCollection($this->conditionPluginManager(), $this->get('visibility'));
+    }
+    return $this->visibilityCollection;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function getVisibilityCondition($instance_id) {
+    return $this->getVisibilityConditions()->get($instance_id);
+  }
+
+  /**
+   * Gets the condition plugin manager.
+   *
+   * @return \Drupal\Core\Executable\ExecutableManagerInterface
+   *   The condition plugin manager.
+   */
+  protected function conditionPluginManager() {
+    if (!isset($this->conditionPluginManager)) {
+      $this->conditionPluginManager = \Drupal::service('plugin.manager.condition');
+    }
+    return $this->conditionPluginManager;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function setRegion($region) {
+    $this->region = $region;
+    return $this;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function setWeight($weight) {
+    $this->weight = $weight;
+    return $this;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function createDuplicateBlock($new_id = NULL, $new_theme = NULL) {
+    $duplicate = parent::createDuplicate();
+    if (!empty($new_id)) {
+      $duplicate->id = $new_id;
+    }
+    if (!empty($new_theme)) {
+      $duplicate->theme = $new_theme;
+    }
+    return $duplicate;
+  }
+
+}

web/core/modules/block/src/EventSubscriber/BlockPageDisplayVariantSubscriber.php

@@ -0,0 +1,34 @@
+<?php
+
+namespace Drupal\block\EventSubscriber;
+
+use Drupal\Core\Render\PageDisplayVariantSelectionEvent;
+use Drupal\Core\Render\RenderEvents;
+use Symfony\Component\EventDispatcher\EventSubscriberInterface;
+
+/**
+ * Selects the block page display variant.
+ *
+ * @see \Drupal\block\Plugin\DisplayVariant\BlockPageVariant
+ */
+class BlockPageDisplayVariantSubscriber implements EventSubscriberInterface {
+
+  /**
+   * Selects the block page display variant.
+   *
+   * @param \Drupal\Core\Render\PageDisplayVariantSelectionEvent $event
+   *   The event to process.
+   */
+  public function onSelectPageDisplayVariant(PageDisplayVariantSelectionEvent $event) {
+    $event->setPluginId('block_page');
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  static function getSubscribedEvents() {
+    $events[RenderEvents::SELECT_PAGE_DISPLAY_VARIANT][] = array('onSelectPageDisplayVariant');
+    return $events;
+  }
+
+}

web/core/modules/block/src/Form/BlockDeleteForm.php

@@ -0,0 +1,20 @@
+<?php
+
+namespace Drupal\block\Form;
+
+use Drupal\Core\Entity\EntityDeleteForm;
+use Drupal\Core\Url;
+
+/**
+ * Provides a deletion confirmation form for the block instance deletion form.
+ */
+class BlockDeleteForm extends EntityDeleteForm {
+
+  /**
+   * {@inheritdoc}
+   */
+  public function getCancelUrl() {
+    return new Url('block.admin_display');
+  }
+
+}

web/core/modules/block/src/Plugin/Derivative/ThemeLocalTask.php

@@ -0,0 +1,66 @@
+<?php
+
+namespace Drupal\block\Plugin\Derivative;
+
+use Drupal\Component\Plugin\Derivative\DeriverBase;
+use Drupal\Core\Extension\ThemeHandlerInterface;
+use Drupal\Core\Plugin\Discovery\ContainerDeriverInterface;
+use Symfony\Component\DependencyInjection\ContainerInterface;
+
+/**
+ * Provides dynamic tabs based on active themes.
+ */
+class ThemeLocalTask extends DeriverBase implements ContainerDeriverInterface {
+
+  /**
+   * The theme handler.
+   *
+   * @var \Drupal\Core\Extension\ThemeHandlerInterface
+   */
+  protected $themeHandler;
+
+  /**
+   * Constructs a new ThemeLocalTask.
+   *
+   * @param \Drupal\Core\Extension\ThemeHandlerInterface $theme_handler
+   *   The theme handler.
+   */
+  public function __construct(ThemeHandlerInterface $theme_handler) {
+    $this->themeHandler = $theme_handler;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public static function create(ContainerInterface $container, $base_plugin_id) {
+    return new static(
+      $container->get('theme_handler')
+    );
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function getDerivativeDefinitions($base_plugin_definition) {
+    $default_theme = $this->themeHandler->getDefault();
+
+    foreach ($this->themeHandler->listInfo() as $theme_name => $theme) {
+      if ($this->themeHandler->hasUi($theme_name)) {
+        $this->derivatives[$theme_name] = $base_plugin_definition;
+        $this->derivatives[$theme_name]['title'] = $theme->info['name'];
+        $this->derivatives[$theme_name]['route_parameters'] = array('theme' => $theme_name);
+      }
+      // Default task!
+      if ($default_theme == $theme_name) {
+        $this->derivatives[$theme_name]['route_name'] = $base_plugin_definition['parent_id'];
+        // Emulate default logic because without the base plugin id we can't
+        // change the base_route.
+        $this->derivatives[$theme_name]['weight'] = -10;
+
+        unset($this->derivatives[$theme_name]['route_parameters']);
+      }
+    }
+    return $this->derivatives;
+  }
+
+}

web/core/modules/block/src/Plugin/DisplayVariant/BlockPageVariant.php

@@ -0,0 +1,203 @@
+<?php
+
+namespace Drupal\block\Plugin\DisplayVariant;
+
+use Drupal\block\BlockRepositoryInterface;
+use Drupal\Core\Block\MainContentBlockPluginInterface;
+use Drupal\Core\Block\TitleBlockPluginInterface;
+use Drupal\Core\Block\MessagesBlockPluginInterface;
+use Drupal\Core\Cache\CacheableMetadata;
+use Drupal\Core\Display\PageVariantInterface;
+use Drupal\Core\Entity\EntityViewBuilderInterface;
+use Drupal\Core\Plugin\ContainerFactoryPluginInterface;
+use Drupal\Core\Display\VariantBase;
+use Symfony\Component\DependencyInjection\ContainerInterface;
+
+/**
+ * Provides a page display variant that decorates the main content with blocks.
+ *
+ * To ensure essential information is displayed, each essential part of a page
+ * has a corresponding block plugin interface, so that BlockPageVariant can
+ * automatically provide a fallback in case no block for each of these
+ * interfaces is placed.
+ *
+ * @see \Drupal\Core\Block\MainContentBlockPluginInterface
+ * @see \Drupal\Core\Block\MessagesBlockPluginInterface
+ *
+ * @PageDisplayVariant(
+ *   id = "block_page",
+ *   admin_label = @Translation("Page with blocks")
+ * )
+ */
+class BlockPageVariant extends VariantBase implements PageVariantInterface, ContainerFactoryPluginInterface {
+
+  /**
+   * The block repository.
+   *
+   * @var \Drupal\block\BlockRepositoryInterface
+   */
+  protected $blockRepository;
+
+  /**
+   * The block view builder.
+   *
+   * @var \Drupal\Core\Entity\EntityViewBuilderInterface
+   */
+  protected $blockViewBuilder;
+
+  /**
+   * The Block entity type list cache tags.
+   *
+   * @var string[]
+   */
+  protected $blockListCacheTags;
+
+  /**
+   * The render array representing the main page content.
+   *
+   * @var array
+   */
+  protected $mainContent = [];
+
+  /**
+   * The page title: a string (plain title) or a render array (formatted title).
+   *
+   * @var string|array
+   */
+  protected $title = '';
+
+  /**
+   * Constructs a new BlockPageVariant.
+   *
+   * @param array $configuration
+   *   A configuration array containing information about the plugin instance.
+   * @param string $plugin_id
+   *   The plugin ID for the plugin instance.
+   * @param mixed $plugin_definition
+   *   The plugin implementation definition.
+   * @param \Drupal\block\BlockRepositoryInterface $block_repository
+   *   The block repository.
+   * @param \Drupal\Core\Entity\EntityViewBuilderInterface $block_view_builder
+   *   The block view builder.
+   * @param string[] $block_list_cache_tags
+   *   The Block entity type list cache tags.
+   */
+  public function __construct(array $configuration, $plugin_id, $plugin_definition, BlockRepositoryInterface $block_repository, EntityViewBuilderInterface $block_view_builder, array $block_list_cache_tags) {
+    parent::__construct($configuration, $plugin_id, $plugin_definition);
+    $this->blockRepository = $block_repository;
+    $this->blockViewBuilder = $block_view_builder;
+    $this->blockListCacheTags = $block_list_cache_tags;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public static function create(ContainerInterface $container, array $configuration, $plugin_id, $plugin_definition) {
+    return new static(
+      $configuration,
+      $plugin_id,
+      $plugin_definition,
+      $container->get('block.repository'),
+      $container->get('entity.manager')->getViewBuilder('block'),
+      $container->get('entity.manager')->getDefinition('block')->getListCacheTags()
+    );
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function setMainContent(array $main_content) {
+    $this->mainContent = $main_content;
+    return $this;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function setTitle($title) {
+    $this->title = $title;
+    return $this;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function build() {
+    // Track whether blocks showing the main content and messages are displayed.
+    $main_content_block_displayed = FALSE;
+    $messages_block_displayed = FALSE;
+
+    $build = [
+      '#cache' => [
+        'tags' => $this->blockListCacheTags,
+      ],
+    ];
+    // Load all region content assigned via blocks.
+    $cacheable_metadata_list = [];
+    foreach ($this->blockRepository->getVisibleBlocksPerRegion($cacheable_metadata_list) as $region => $blocks) {
+      /** @var $blocks \Drupal\block\BlockInterface[] */
+      foreach ($blocks as $key => $block) {
+        $block_plugin = $block->getPlugin();
+        if ($block_plugin instanceof MainContentBlockPluginInterface) {
+          $block_plugin->setMainContent($this->mainContent);
+          $main_content_block_displayed = TRUE;
+        }
+        elseif ($block_plugin instanceof TitleBlockPluginInterface) {
+          $block_plugin->setTitle($this->title);
+        }
+        elseif ($block_plugin instanceof MessagesBlockPluginInterface) {
+          $messages_block_displayed = TRUE;
+        }
+        $build[$region][$key] = $this->blockViewBuilder->view($block);
+
+        // The main content block cannot be cached: it is a placeholder for the
+        // render array returned by the controller. It should be rendered as-is,
+        // with other placed blocks "decorating" it. Analogous reasoning for the
+        // title block.
+        if ($block_plugin instanceof MainContentBlockPluginInterface || $block_plugin instanceof TitleBlockPluginInterface) {
+          unset($build[$region][$key]['#cache']['keys']);
+        }
+      }
+      if (!empty($build[$region])) {
+        // \Drupal\block\BlockRepositoryInterface::getVisibleBlocksPerRegion()
+        // returns the blocks in sorted order.
+        $build[$region]['#sorted'] = TRUE;
+      }
+    }
+
+    // If no block that shows the main content is displayed, still show the main
+    // content. Otherwise the end user will see all displayed blocks, but not
+    // the main content they came for.
+    if (!$main_content_block_displayed) {
+      $build['content']['system_main'] = $this->mainContent;
+    }
+
+    // If no block displays status messages, still render them.
+    if (!$messages_block_displayed) {
+      $build['content']['messages'] = [
+        '#weight' => -1000,
+        '#type' => 'status_messages',
+      ];
+    }
+
+    // If any render arrays are manually placed, render arrays and blocks must
+    // be sorted.
+    if (!$main_content_block_displayed || !$messages_block_displayed) {
+      unset($build['content']['#sorted']);
+    }
+
+    // The access results' cacheability is currently added to the top level of the
+    // render array. This is done to prevent issues with empty regions being
+    // displayed.
+    // This would need to be changed to allow caching of block regions, as each
+    // region must then have the relevant cacheable metadata.
+    $merged_cacheable_metadata = CacheableMetadata::createFromRenderArray($build);
+    foreach ($cacheable_metadata_list as $cacheable_metadata) {
+      $merged_cacheable_metadata = $merged_cacheable_metadata->merge($cacheable_metadata);
+    }
+    $merged_cacheable_metadata->applyTo($build);
+
+    return $build;
+  }
+
+}

web/core/modules/block/src/Plugin/migrate/destination/EntityBlock.php

@@ -0,0 +1,28 @@
+<?php
+
+namespace Drupal\block\Plugin\migrate\destination;
+
+use Drupal\migrate\Plugin\migrate\destination\EntityConfigBase;
+use Drupal\migrate\Row;
+
+/**
+ * @MigrateDestination(
+ *   id = "entity:block"
+ * )
+ */
+class EntityBlock extends EntityConfigBase {
+
+  /**
+   * {@inheritdoc}
+   */
+  protected function getEntityId(Row $row) {
+    // Try to find the block by its plugin ID and theme.
+    $properties = array(
+      'plugin' => $row->getDestinationProperty('plugin'),
+      'theme' => $row->getDestinationProperty('theme'),
+    );
+    $blocks = array_keys($this->storage->loadByProperties($properties));
+    return reset($blocks);
+  }
+
+}

web/core/modules/block/src/Plugin/migrate/process/BlockPluginId.php

@@ -0,0 +1,100 @@
+<?php
+
+namespace Drupal\block\Plugin\migrate\process;
+
+use Drupal\Core\Entity\EntityStorageInterface;
+use Drupal\Core\Plugin\ContainerFactoryPluginInterface;
+use Drupal\migrate\Plugin\MigrationInterface;
+use Drupal\migrate\MigrateExecutableInterface;
+use Drupal\migrate\Plugin\MigrateProcessInterface;
+use Drupal\migrate\ProcessPluginBase;
+use Drupal\migrate\Row;
+use Symfony\Component\DependencyInjection\ContainerInterface;
+
+/**
+ * @MigrateProcessPlugin(
+ *   id = "block_plugin_id"
+ * )
+ */
+class BlockPluginId extends ProcessPluginBase implements ContainerFactoryPluginInterface {
+
+  /**
+   * The migration process plugin, configured for lookups in d6_custom_block
+   * and d7_custom_block.
+   *
+   * @var \Drupal\migrate\Plugin\MigrateProcessInterface
+   */
+  protected $migrationPlugin;
+
+  /**
+   * The block_content entity storage handler.
+   *
+   * @var \Drupal\Core\Entity\EntityStorageInterface
+   */
+  protected $blockContentStorage;
+
+  /**
+   * {@inheritdoc}
+   */
+  public function __construct(array $configuration, $plugin_id, array $plugin_definition, EntityStorageInterface $storage, MigrateProcessInterface $migration_plugin) {
+    parent::__construct($configuration, $plugin_id, $plugin_definition);
+    $this->blockContentStorage = $storage;
+    $this->migrationPlugin = $migration_plugin;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public static function create(ContainerInterface $container, array $configuration, $plugin_id, $plugin_definition, MigrationInterface $migration = NULL) {
+    $entity_manager = $container->get('entity.manager');
+    $migration_configuration = array(
+      'migration' => array(
+        'd6_custom_block',
+        'd7_custom_block',
+      ),
+    );
+    return new static(
+      $configuration,
+      $plugin_id,
+      $plugin_definition,
+      $entity_manager->getDefinition('block_content') ? $entity_manager->getStorage('block_content') : NULL,
+      $container->get('plugin.manager.migrate.process')->createInstance('migration', $migration_configuration, $migration)
+    );
+  }
+
+  /**
+   * {@inheritdoc}
+   *
+   * Set the block plugin id.
+   */
+  public function transform($value, MigrateExecutableInterface $migrate_executable, Row $row, $destination_property) {
+    if (is_array($value)) {
+      list($module, $delta) = $value;
+      switch ($module) {
+        case 'aggregator':
+          list($type, $id) = explode('-', $delta);
+          if ($type == 'feed') {
+            return 'aggregator_feed_block';
+          }
+          break;
+        case 'menu':
+          return "system_menu_block:$delta";
+        case 'block':
+          if ($this->blockContentStorage) {
+            $block_id = $this->migrationPlugin
+              ->transform($delta, $migrate_executable, $row, $destination_property);
+            if ($block_id) {
+              return 'block_content:' . $this->blockContentStorage->load($block_id)->uuid();
+            }
+          }
+          break;
+        default:
+          break;
+      }
+    }
+    else {
+      return $value;
+    }
+  }
+
+}

web/core/modules/block/src/Plugin/migrate/process/BlockRegion.php

@@ -0,0 +1,73 @@
+<?php
+
+namespace Drupal\block\Plugin\migrate\process;
+
+use Drupal\Core\Plugin\ContainerFactoryPluginInterface;
+use Drupal\migrate\MigrateExecutableInterface;
+use Drupal\migrate\Plugin\migrate\process\StaticMap;
+use Drupal\migrate\Row;
+use Symfony\Component\DependencyInjection\ContainerInterface;
+
+/**
+ * @MigrateProcessPlugin(
+ *   id = "block_region"
+ * )
+ */
+class BlockRegion extends StaticMap implements ContainerFactoryPluginInterface {
+
+  /**
+   * List of regions, keyed by theme.
+   *
+   * @var array[]
+   */
+  protected $regions;
+
+  /**
+   * Constructs a BlockRegion plugin instance.
+   *
+   * @param array $configuration
+   *   The plugin configuration.
+   * @param string $plugin_id
+   *   The plugin ID.
+   * @param mixed $plugin_definition
+   *   The plugin definition.
+   * @param array $regions
+   *   Array of region maps, keyed by theme.
+   */
+  public function __construct(array $configuration, $plugin_id, $plugin_definition, array $regions) {
+    parent::__construct($configuration, $plugin_id, $plugin_definition);
+    $this->regions = $regions;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public static function create(ContainerInterface $container, array $configuration, $plugin_id, $plugin_definition) {
+    $regions = array();
+    foreach ($container->get('theme_handler')->listInfo() as $key => $theme) {
+      $regions[$key] = $theme->info['regions'];
+    }
+    return new static($configuration, $plugin_id, $plugin_definition, $regions);
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function transform($value, MigrateExecutableInterface $migrate_executable, Row $row, $destination_property) {
+    // Set the destination region, based on the source region and theme as well
+    // as the current destination default theme.
+    list($source_theme, $destination_theme, $region) = $value;
+
+    // Theme is the same on both source and destination, so ensure that the
+    // region exists in the destination theme.
+    if (strtolower($source_theme) == strtolower($destination_theme)) {
+      if (isset($this->regions[$destination_theme][$region])) {
+        return $region;
+      }
+    }
+
+    // Fall back to static mapping.
+    return parent::transform($value, $migrate_executable, $row, $destination_property);
+  }
+
+}

web/core/modules/block/src/Plugin/migrate/process/BlockSettings.php

@@ -0,0 +1,60 @@
+<?php
+
+namespace Drupal\block\Plugin\migrate\process;
+
+use Drupal\block\BlockInterface;
+use Drupal\migrate\MigrateExecutableInterface;
+use Drupal\migrate\ProcessPluginBase;
+use Drupal\migrate\Row;
+
+/**
+ * @MigrateProcessPlugin(
+ *   id = "block_settings"
+ * )
+ */
+class BlockSettings extends ProcessPluginBase {
+
+  /**
+   * {@inheritdoc}
+   *
+   * Set the block configuration.
+   */
+  public function transform($value, MigrateExecutableInterface $migrate_executable, Row $row, $destination_property) {
+    list($plugin, $delta, $old_settings, $title) = $value;
+    $settings = array();
+    $settings['label'] = $title;
+    if ($title) {
+      $settings['label_display'] = BlockInterface::BLOCK_LABEL_VISIBLE;
+    }
+    else {
+      $settings['label_display'] = '0';
+    }
+    switch ($plugin) {
+      case 'aggregator_feed_block':
+        list(, $id) = explode('-', $delta);
+        $settings['block_count'] = $old_settings['aggregator']['item_count'];
+        $settings['feed'] = $id;
+        break;
+      case 'book_navigation':
+        $settings['block_mode'] = $old_settings['book']['block_mode'];
+        break;
+      case 'forum_active_block':
+      case 'forum_new_block':
+        $settings['block_count'] = $old_settings['forum']['block_num'];
+        break;
+      case 'statistics_popular_block':
+        $settings['top_day_num'] = $old_settings['statistics']['statistics_block_top_day_num'];
+        $settings['top_all_num'] = $old_settings['statistics']['statistics_block_top_all_num'];
+        $settings['top_last_num'] = $old_settings['statistics']['statistics_block_top_last_num'];
+        break;
+      case 'views_block:who_s_new-block_1':
+        $settings['items_per_page'] = $old_settings['user']['block_whois_new_count'];
+        break;
+      case 'views_block:who_s_online-who_s_online_block':
+        $settings['items_per_page'] = $old_settings['user']['max_list_count'];
+        break;
+    }
+    return $settings;
+  }
+
+}

web/core/modules/block/src/Plugin/migrate/process/BlockTheme.php

@@ -0,0 +1,97 @@
+<?php
+
+namespace Drupal\block\Plugin\migrate\process;
+
+use Drupal\migrate\Plugin\MigrationInterface;
+use Drupal\migrate\MigrateExecutableInterface;
+use Drupal\migrate\ProcessPluginBase;
+use Drupal\migrate\Row;
+use Drupal\Core\Config\Config;
+use Drupal\Core\Plugin\ContainerFactoryPluginInterface;
+use Symfony\Component\DependencyInjection\ContainerInterface;
+
+/**
+ * @MigrateProcessPlugin(
+ *   id = "block_theme"
+ * )
+ */
+class BlockTheme extends ProcessPluginBase implements ContainerFactoryPluginInterface {
+
+  /**
+   * Contains the configuration object factory.
+   *
+   * @var \Drupal\Core\Config\ConfigFactoryInterface
+   */
+  protected $configFactory;
+
+  /**
+   * Contains the system.theme configuration object.
+   *
+   * @var \Drupal\Core\Config\Config
+   */
+  protected $themeConfig;
+
+  /**
+   * Constructs a BlockTheme object.
+   *
+   * @param array $configuration
+   *   A configuration array containing information about the plugin instance.
+   * @param string $plugin_id
+   *   The plugin ID for the plugin instance.
+   * @param mixed $plugin_definition
+   *   The plugin implementation definition.
+   * @param \Drupal\migrate\Plugin\MigrationInterface $migration
+   *   The migration entity.
+   * @param \Drupal\Core\Config\Config $theme_config
+   *   The system.theme configuration factory object.
+   * @param array $themes
+   *   The list of themes available on the destination.
+   */
+  public function __construct(array $configuration, $plugin_id, $plugin_definition, MigrationInterface $migration, Config $theme_config, array $themes) {
+    parent::__construct($configuration, $plugin_id, $plugin_definition, $migration);
+    $this->themeConfig = $theme_config;
+    $this->themes = $themes;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public static function create(ContainerInterface $container, array $configuration, $plugin_id, $plugin_definition, MigrationInterface $migration = NULL) {
+    return new static(
+      $configuration,
+      $plugin_id,
+      $plugin_definition,
+      $migration,
+      $container->get('config.factory')->get('system.theme'),
+      $container->get('theme_handler')->listInfo()
+    );
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function transform($value, MigrateExecutableInterface $migrate_executable, Row $row, $destination_property) {
+    list($theme, $default_theme, $admin_theme) = $value;
+
+    // If the source theme exists on the destination, we're good.
+    if (isset($this->themes[$theme])) {
+      return $theme;
+    }
+
+    // If the source block is assigned to a region in the source default theme,
+    // then assign it to the destination default theme.
+    if (strtolower($theme) == strtolower($default_theme)) {
+      return $this->themeConfig->get('default');
+    }
+
+    // If the source block is assigned to a region in the source admin theme,
+    // then assign it to the destination admin theme.
+    if (strtolower($theme) == strtolower($admin_theme)) {
+      return $this->themeConfig->get('admin');
+    }
+
+    // We couldn't map it to a D8 theme so just return the incoming theme.
+    return $theme;
+  }
+
+}

web/core/modules/block/src/Plugin/migrate/process/BlockVisibility.php

@@ -0,0 +1,137 @@
+<?php
+
+namespace Drupal\block\Plugin\migrate\process;
+
+use Drupal\Core\Extension\ModuleHandlerInterface;
+use Drupal\Core\Plugin\ContainerFactoryPluginInterface;
+use Drupal\migrate\Plugin\MigrationInterface;
+use Drupal\migrate\MigrateExecutableInterface;
+use Drupal\migrate\MigrateSkipRowException;
+use Drupal\migrate\Plugin\MigrateProcessInterface;
+use Drupal\migrate\ProcessPluginBase;
+use Drupal\migrate\Row;
+use Symfony\Component\DependencyInjection\ContainerInterface;
+
+/**
+ * @MigrateProcessPlugin(
+ *   id = "block_visibility"
+ * )
+ */
+class BlockVisibility extends ProcessPluginBase implements ContainerFactoryPluginInterface {
+
+  /**
+   * The module handler.
+   *
+   * @var \Drupal\Core\Extension\ModuleHandlerInterface
+   */
+  protected $moduleHandler;
+
+  /**
+   * The migration process plugin, configured for lookups in the d6_user_role
+   * and d7_user_role migrations.
+   *
+   * @var \Drupal\migrate\Plugin\MigrateProcessInterface
+   */
+  protected $migrationPlugin;
+
+  /**
+   * Whether or not to skip blocks that use PHP for visibility. Only applies
+   * if the PHP module is not enabled.
+   *
+   * @var bool
+   */
+  protected $skipPHP = FALSE;
+
+  /**
+   * {@inheritdoc}
+   */
+  public function __construct(array $configuration, $plugin_id, $plugin_definition, ModuleHandlerInterface $module_handler, MigrateProcessInterface $migration_plugin) {
+    parent::__construct($configuration, $plugin_id, $plugin_definition);
+    $this->moduleHandler = $module_handler;
+    $this->migrationPlugin = $migration_plugin;
+
+    if (isset($configuration['skip_php'])) {
+      $this->skipPHP = $configuration['skip_php'];
+    }
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public static function create(ContainerInterface $container, array $configuration, $plugin_id, $plugin_definition, MigrationInterface $migration = NULL) {
+    $migration_configuration = array(
+      'migration' => array(
+        'd6_user_role',
+        'd7_user_role',
+      ),
+    );
+    return new static(
+      $configuration,
+      $plugin_id,
+      $plugin_definition,
+      $container->get('module_handler'),
+      $container->get('plugin.manager.migrate.process')->createInstance('migration', $migration_configuration, $migration)
+    );
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function transform($value, MigrateExecutableInterface $migrate_executable, Row $row, $destination_property) {
+    list($old_visibility, $pages, $roles) = $value;
+
+    $visibility = array();
+
+    // If the block is assigned to specific roles, add the user_role condition.
+    if ($roles) {
+      $visibility['user_role'] = array(
+        'id' => 'user_role',
+        'roles' => array(),
+        'context_mapping' => array(
+          'user' => '@user.current_user_context:current_user',
+        ),
+        'negate' => FALSE,
+      );
+
+      foreach ($roles as $key => $role_id) {
+        $roles[$key] = $this->migrationPlugin->transform($role_id, $migrate_executable, $row, $destination_property);
+      }
+      $visibility['user_role']['roles'] = array_combine($roles, $roles);
+    }
+
+    if ($pages) {
+      // 2 == BLOCK_VISIBILITY_PHP in Drupal 6 and 7.
+      if ($old_visibility == 2) {
+        // If the PHP module is present, migrate the visibility code unaltered.
+        if ($this->moduleHandler->moduleExists('php')) {
+          $visibility['php'] = array(
+            'id' => 'php',
+            // PHP code visibility could not be negated in Drupal 6 or 7.
+            'negate' => FALSE,
+            'php' => $pages,
+          );
+        }
+        // Skip the row if we're configured to. If not, we don't need to do
+        // anything else -- the block will simply have no PHP or request_path
+        // visibility configuration.
+        elseif ($this->skipPHP) {
+          throw new MigrateSkipRowException();
+        }
+      }
+      else {
+        $paths = preg_split("(\r\n?|\n)", $pages);
+        foreach ($paths as $key => $path) {
+          $paths[$key] = $path === '<front>' ? $path : '/' . ltrim($path, '/');
+        }
+        $visibility['request_path'] = array(
+          'id' => 'request_path',
+          'negate' => !$old_visibility,
+          'pages' => implode("\n", $paths),
+        );
+      }
+    }
+
+    return $visibility;
+  }
+
+}

web/core/modules/block/src/Plugin/migrate/source/Block.php

@@ -0,0 +1,177 @@
+<?php
+
+namespace Drupal\block\Plugin\migrate\source;
+
+use Drupal\migrate\Row;
+use Drupal\migrate_drupal\Plugin\migrate\source\DrupalSqlBase;
+
+/**
+ * Drupal block source from database.
+ *
+ * @MigrateSource(
+ *   id = "block",
+ *   source_provider = "block"
+ * )
+ */
+class Block extends DrupalSqlBase {
+
+  /**
+   * The default theme name.
+   *
+   * @var string
+   */
+  protected $defaultTheme;
+
+  /**
+   * The admin theme name.
+   *
+   * @var string
+   */
+  protected $adminTheme;
+
+  /**
+   * Table containing block configuration.
+   *
+   * @var string
+   */
+  protected $blockTable;
+
+  /**
+   * Table mapping blocks to user roles.
+   *
+   * @var string
+   */
+  protected $blockRoleTable;
+
+  /**
+   * Table listing user roles.
+   *
+   * @var string
+   */
+  protected $userRoleTable;
+
+  /**
+   * {@inheritdoc}
+   */
+  public function query() {
+    if ($this->getModuleSchemaVersion('system') >= 7000) {
+      $this->blockTable = 'block';
+      $this->blockRoleTable = 'block_role';
+    }
+    else {
+      $this->blockTable = 'blocks';
+      $this->blockRoleTable = 'blocks_roles';
+    }
+    // Drupal 6 & 7 both use the same name for the user roles table.
+    $this->userRoleTable = 'role';
+
+    return $this->select($this->blockTable, 'b')->fields('b');
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  protected function initializeIterator() {
+    $this->defaultTheme = $this->variableGet('theme_default', 'Garland');
+    $this->adminTheme = $this->variableGet('admin_theme', NULL);
+    return parent::initializeIterator();
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function fields() {
+    return array(
+      'bid' => $this->t('The block numeric identifier.'),
+      'module' => $this->t('The module providing the block.'),
+      'delta' => $this->t('The block\'s delta.'),
+      'theme' => $this->t('Which theme the block is placed in.'),
+      'status' => $this->t('Whether or not the block is enabled.'),
+      'weight' => $this->t('Weight of the block for ordering within regions.'),
+      'region' => $this->t('Region the block is placed in.'),
+      'visibility' => $this->t('Visibility expression.'),
+      'pages' => $this->t('Pages list.'),
+      'title' => $this->t('Block title.'),
+      'cache' => $this->t('Cache rule.'),
+    );
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function getIds() {
+    $ids['module']['type'] = 'string';
+    $ids['delta']['type'] = 'string';
+    $ids['theme']['type'] = 'string';
+    return $ids;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function prepareRow(Row $row) {
+    $row->setSourceProperty('default_theme', $this->defaultTheme);
+    $row->setSourceProperty('admin_theme', $this->adminTheme);
+
+    $module = $row->getSourceProperty('module');
+    $delta = $row->getSourceProperty('delta');
+
+    $query = $this->select($this->blockRoleTable, 'br')
+      ->fields('br', array('rid'))
+      ->condition('module', $module)
+      ->condition('delta', $delta);
+    $query->join($this->userRoleTable, 'ur', 'br.rid = ur.rid');
+    $roles = $query->execute()
+      ->fetchCol();
+    $row->setSourceProperty('roles', $roles);
+
+    $settings = array();
+    switch ($module) {
+      case 'aggregator':
+        list($type, $id) = explode('-', $delta);
+        if ($type == 'feed') {
+          $item_count = $this->select('aggregator_feed', 'af')
+            ->fields('af', ['block'])
+            ->condition('fid', $id)
+            ->execute()
+            ->fetchField();
+        }
+        else {
+          $item_count = $this->select('aggregator_category', 'ac')
+            ->fields('ac', ['block'])
+            ->condition('cid', $id)
+            ->execute()
+            ->fetchField();
+        }
+        $settings['aggregator']['item_count'] = $item_count;
+        break;
+      case 'book':
+        $settings['book']['block_mode'] = $this->variableGet('book_block_mode', 'all pages');
+        break;
+      case 'forum':
+        $settings['forum']['block_num'] = $this->variableGet('forum_block_num_' . $delta, 5);
+        break;
+      case 'statistics':
+        foreach (array('statistics_block_top_day_num', 'statistics_block_top_all_num', 'statistics_block_top_last_num') as $name) {
+          $settings['statistics'][$name] = $this->variableGet($name, 0);
+        }
+        break;
+      case 'user':
+        switch ($delta) {
+          case 2:
+          case 'new':
+            $settings['user']['block_whois_new_count'] = $this->variableGet('user_block_whois_new_count', 5);
+            break;
+          case 3:
+          case 'online':
+            $settings['user']['block_seconds_online'] = $this->variableGet('user_block_seconds_online', 900);
+            $settings['user']['max_list_count'] = $this->variableGet('user_block_max_list_count', 10);
+            break;
+        }
+        break;
+    }
+    $row->setSourceProperty('settings', $settings);
+    return parent::prepareRow($row);
+  }
+
+}

web/core/modules/block/src/Tests/BlockAdminThemeTest.php

@@ -0,0 +1,77 @@
+<?php
+
+namespace Drupal\block\Tests;
+
+use Drupal\simpletest\WebTestBase;
+
+/**
+ * Tests the block system with admin themes.
+ *
+ * @group block
+ */
+class BlockAdminThemeTest extends WebTestBase {
+
+  /**
+   * Modules to install.
+   *
+   * @var array
+   */
+  public static $modules = array('block', 'contextual');
+
+  /**
+   * Check for the accessibility of the admin theme on the block admin page.
+   */
+  function testAdminTheme() {
+    // Create administrative user.
+    $admin_user = $this->drupalCreateUser(array('administer blocks', 'administer themes'));
+    $this->drupalLogin($admin_user);
+
+    // Ensure that access to block admin page is denied when theme is not
+    // installed.
+    $this->drupalGet('admin/structure/block/list/bartik');
+    $this->assertResponse(403);
+
+    // Install admin theme and confirm that tab is accessible.
+    \Drupal::service('theme_handler')->install(array('bartik'));
+    $edit['admin_theme'] = 'bartik';
+    $this->drupalPostForm('admin/appearance', $edit, t('Save configuration'));
+    $this->drupalGet('admin/structure/block/list/bartik');
+    $this->assertResponse(200);
+  }
+
+  /**
+   * Ensure contextual links are disabled in Seven theme.
+   */
+  function testSevenAdminTheme() {
+    // Create administrative user.
+    $admin_user = $this->drupalCreateUser([
+      'access administration pages',
+      'administer themes',
+      'access contextual links',
+      'view the administration theme',
+    ]);
+    $this->drupalLogin($admin_user);
+
+    // Install admin theme and confirm that tab is accessible.
+    \Drupal::service('theme_handler')->install(['seven']);
+    $edit['admin_theme'] = 'seven';
+    $this->drupalPostForm('admin/appearance', $edit, t('Save configuration'));
+
+    // Define our block settings.
+    $settings = [
+      'theme' => 'seven',
+      'region' => 'header',
+    ];
+
+    // Place a block.
+    $block = $this->drupalPlaceBlock('local_tasks_block', $settings);
+
+    // Open admin page.
+    $this->drupalGet('admin');
+
+    // Check if contextual link classes are unavailable.
+    $this->assertNoRaw('<div data-contextual-id="block:block=' . $block->id() . ':langcode=en"></div>');
+    $this->assertNoRaw('contextual-region');
+  }
+
+}

web/core/modules/block/src/Tests/BlockCacheTest.php

@@ -0,0 +1,215 @@
+<?php
+
+namespace Drupal\block\Tests;
+
+use Drupal\Core\Cache\Cache;
+use Drupal\simpletest\WebTestBase;
+
+/**
+ * Tests block caching.
+ *
+ * @group block
+ */
+class BlockCacheTest extends WebTestBase {
+
+  /**
+   * Modules to install.
+   *
+   * @var array
+   */
+  public static $modules = array('block', 'block_test', 'test_page_test');
+
+  /**
+   * A user with permission to create and edit books and to administer blocks.
+   *
+   * @var object
+   */
+  protected $adminUser;
+
+  /**
+   * An authenticated user to test block caching.
+   *
+   * @var object
+   */
+  protected $normalUser;
+
+  /**
+   * Another authenticated user to test block caching.
+   *
+   * @var object
+   */
+  protected $normalUserAlt;
+
+  /**
+   * The block used by this test.
+   *
+   * @var \Drupal\block\BlockInterface
+   */
+  protected $block;
+
+  protected function setUp() {
+    parent::setUp();
+
+    // Create an admin user, log in and enable test blocks.
+    $this->adminUser = $this->drupalCreateUser(array('administer blocks', 'access administration pages'));
+    $this->drupalLogin($this->adminUser);
+
+    // Create additional users to test caching modes.
+    $this->normalUser = $this->drupalCreateUser();
+    $this->normalUserAlt = $this->drupalCreateUser();
+    // Sync the roles, since drupalCreateUser() creates separate roles for
+    // the same permission sets.
+    $this->normalUserAlt->roles = $this->normalUser->getRoles();
+    $this->normalUserAlt->save();
+
+    // Enable our test block.
+    $this->block = $this->drupalPlaceBlock('test_cache');
+  }
+
+  /**
+   * Test "user.roles" cache context.
+   */
+  function testCachePerRole() {
+    \Drupal::state()->set('block_test.cache_contexts', ['user.roles']);
+
+    // Enable our test block. Set some content for it to display.
+    $current_content = $this->randomMachineName();
+    \Drupal::state()->set('block_test.content', $current_content);
+    $this->drupalLogin($this->normalUser);
+    $this->drupalGet('');
+    $this->assertText($current_content, 'Block content displays.');
+
+    // Change the content, but the cached copy should still be served.
+    $old_content = $current_content;
+    $current_content = $this->randomMachineName();
+    \Drupal::state()->set('block_test.content', $current_content);
+    $this->drupalGet('');
+    $this->assertText($old_content, 'Block is served from the cache.');
+
+    // Clear the cache and verify that the stale data is no longer there.
+    Cache::invalidateTags(array('block_view'));
+    $this->drupalGet('');
+    $this->assertNoText($old_content, 'Block cache clear removes stale cache data.');
+    $this->assertText($current_content, 'Fresh block content is displayed after clearing the cache.');
+
+    // Test whether the cached data is served for the correct users.
+    $old_content = $current_content;
+    $current_content = $this->randomMachineName();
+    \Drupal::state()->set('block_test.content', $current_content);
+    $this->drupalLogout();
+    $this->drupalGet('');
+    $this->assertNoText($old_content, 'Anonymous user does not see content cached per-role for normal user.');
+
+    $this->drupalLogin($this->normalUserAlt);
+    $this->drupalGet('');
+    $this->assertText($old_content, 'User with the same roles sees per-role cached content.');
+
+    $this->drupalLogin($this->adminUser);
+    $this->drupalGet('');
+    $this->assertNoText($old_content, 'Admin user does not see content cached per-role for normal user.');
+
+    $this->drupalLogin($this->normalUser);
+    $this->drupalGet('');
+    $this->assertText($old_content, 'Block is served from the per-role cache.');
+  }
+
+  /**
+   * Test a cacheable block without any additional cache context.
+   */
+  function testCachePermissions() {
+    // user.permissions is a required context, so a user with different
+    // permissions will see a different version of the block.
+    \Drupal::state()->set('block_test.cache_contexts', []);
+
+    $current_content = $this->randomMachineName();
+    \Drupal::state()->set('block_test.content', $current_content);
+
+    $this->drupalGet('');
+    $this->assertText($current_content, 'Block content displays.');
+
+    $old_content = $current_content;
+    $current_content = $this->randomMachineName();
+    \Drupal::state()->set('block_test.content', $current_content);
+
+    $this->drupalGet('user');
+    $this->assertText($old_content, 'Block content served from cache.');
+
+    $this->drupalLogout();
+    $this->drupalGet('user');
+    $this->assertText($current_content, 'Block content not served from cache.');
+  }
+
+  /**
+   * Test non-cacheable block.
+   */
+  function testNoCache() {
+    \Drupal::state()->set('block_test.cache_max_age', 0);
+
+    $current_content = $this->randomMachineName();
+    \Drupal::state()->set('block_test.content', $current_content);
+
+    // If max_age = 0 has no effect, the next request would be cached.
+    $this->drupalGet('');
+    $this->assertText($current_content, 'Block content displays.');
+
+    // A cached copy should not be served.
+    $current_content = $this->randomMachineName();
+    \Drupal::state()->set('block_test.content', $current_content);
+    $this->drupalGet('');
+    $this->assertText($current_content, 'Maximum age of zero prevents blocks from being cached.');
+  }
+
+  /**
+   * Test "user" cache context.
+   */
+  function testCachePerUser() {
+    \Drupal::state()->set('block_test.cache_contexts', ['user']);
+
+    $current_content = $this->randomMachineName();
+    \Drupal::state()->set('block_test.content', $current_content);
+    $this->drupalLogin($this->normalUser);
+
+    $this->drupalGet('');
+    $this->assertText($current_content, 'Block content displays.');
+
+    $old_content = $current_content;
+    $current_content = $this->randomMachineName();
+    \Drupal::state()->set('block_test.content', $current_content);
+
+    $this->drupalGet('');
+    $this->assertText($old_content, 'Block is served from per-user cache.');
+
+    $this->drupalLogin($this->normalUserAlt);
+    $this->drupalGet('');
+    $this->assertText($current_content, 'Per-user block cache is not served for other users.');
+
+    $this->drupalLogin($this->normalUser);
+    $this->drupalGet('');
+    $this->assertText($old_content, 'Per-user block cache is persistent.');
+  }
+
+  /**
+   * Test "url" cache context.
+   */
+  function testCachePerPage() {
+    \Drupal::state()->set('block_test.cache_contexts', ['url']);
+
+    $current_content = $this->randomMachineName();
+    \Drupal::state()->set('block_test.content', $current_content);
+
+    $this->drupalGet('test-page');
+    $this->assertText($current_content, 'Block content displays on the test page.');
+
+    $old_content = $current_content;
+    $current_content = $this->randomMachineName();
+    \Drupal::state()->set('block_test.content', $current_content);
+
+    $this->drupalGet('user');
+    $this->assertResponse(200);
+    $this->assertNoText($old_content, 'Block content cached for the test page does not show up for the user page.');
+    $this->drupalGet('test-page');
+    $this->assertResponse(200);
+    $this->assertText($old_content, 'Block content cached for the test page.');
+  }
+
+}

web/core/modules/block/src/Tests/BlockFormInBlockTest.php

@@ -0,0 +1,71 @@
+<?php
+
+namespace Drupal\block\Tests;
+
+use Drupal\simpletest\WebTestBase;
+
+/**
+ * Tests form in block caching.
+ *
+ * @group block
+ */
+class BlockFormInBlockTest extends WebTestBase {
+
+  /**
+   * Modules to install.
+   *
+   * @var array
+   */
+  public static $modules = ['block', 'block_test', 'test_page_test'];
+
+  /**
+   * {@inheritdoc}
+   */
+  protected function setUp() {
+    parent::setUp();
+
+    // Enable our test block.
+    $this->drupalPlaceBlock('test_form_in_block');
+  }
+
+  /**
+   * Test to see if form in block's redirect isn't cached.
+   */
+  function testCachePerPage() {
+    $form_values = ['email' => 'test@example.com'];
+
+    // Go to "test-page" and test if the block is enabled.
+    $this->drupalGet('test-page');
+    $this->assertResponse(200);
+    $this->assertText('Your .com email address.', 'form found');
+
+    // Make sure that we're currently still on /test-page after submitting the
+    // form.
+    $this->drupalPostForm(NULL, $form_values, t('Submit'));
+    $this->assertUrl('test-page');
+    $this->assertText(t('Your email address is @email', ['@email' => 'test@example.com']));
+
+    // Go to a different page and see if the block is enabled there as well.
+    $this->drupalGet('test-render-title');
+    $this->assertResponse(200);
+    $this->assertText('Your .com email address.', 'form found');
+
+    // Make sure that submitting the form didn't redirect us to the first page
+    // we submitted the form from after submitting the form from
+    // /test-render-title.
+    $this->drupalPostForm(NULL, $form_values, t('Submit'));
+    $this->assertUrl('test-render-title');
+    $this->assertText(t('Your email address is @email', ['@email' => 'test@example.com']));
+  }
+
+  /**
+   * Test the actual placeholders
+   */
+  public function testPlaceholders() {
+    $this->drupalGet('test-multiple-forms');
+
+    $placeholder = 'form_action_' . hash('crc32b', 'Drupal\Core\Form\FormBuilder::prepareForm');
+    $this->assertText('Form action: ' . $placeholder, 'placeholder found.');
+  }
+
+}

web/core/modules/block/src/Tests/BlockHiddenRegionTest.php

@@ -0,0 +1,73 @@
+<?php
+
+namespace Drupal\block\Tests;
+
+use Drupal\simpletest\WebTestBase;
+
+/**
+ * Tests that a newly installed theme does not inherit blocks to its hidden
+ * regions.
+ *
+ * @group block
+ */
+class BlockHiddenRegionTest extends WebTestBase {
+
+  /**
+   * An administrative user to configure the test environment.
+   */
+  protected $adminUser;
+
+  /**
+   * Modules to install.
+   *
+   * @var array
+   */
+  public static $modules = array('block', 'block_test', 'search');
+
+  protected function setUp() {
+    parent::setUp();
+
+    // Create administrative user.
+    $this->adminUser = $this->drupalCreateUser(array(
+      'administer blocks',
+      'administer themes',
+      'search content',
+      )
+    );
+
+    $this->drupalLogin($this->adminUser);
+    $this->drupalPlaceBlock('search_form_block');
+    $this->drupalPlaceBlock('local_tasks_block');
+  }
+
+  /**
+   * Tests that hidden regions do not inherit blocks when a theme is installed.
+   */
+  public function testBlockNotInHiddenRegion() {
+
+    // Ensure that the search form block is displayed.
+    $this->drupalGet('');
+    $this->assertText('Search', 'Block was displayed on the front page.');
+
+    // Install "block_test_theme" and set it as the default theme.
+    $theme = 'block_test_theme';
+    // We need to install a non-hidden theme so that there is more than one
+    // local task.
+    \Drupal::service('theme_handler')->install(array($theme, 'stark'));
+    $this->config('system.theme')
+      ->set('default', $theme)
+      ->save();
+    // Installing a theme will cause the kernel terminate event to rebuild the
+    // router. Simulate that here.
+    \Drupal::service('router.builder')->rebuildIfNeeded();
+
+    // Ensure that "block_test_theme" is set as the default theme.
+    $this->drupalGet('admin/structure/block');
+    $this->assertText('Block test theme(' . t('active tab') . ')', 'Default local task on blocks admin page is the block test theme.');
+
+    // Ensure that the search form block is displayed.
+    $this->drupalGet('');
+    $this->assertText('Search', 'Block was displayed on the front page.');
+  }
+
+}

web/core/modules/block/src/Tests/BlockHookOperationTest.php

@@ -0,0 +1,51 @@
+<?php
+
+namespace Drupal\block\Tests;
+
+use Drupal\Component\Utility\Unicode;
+use Drupal\simpletest\WebTestBase;
+
+/**
+ * Tests for Block module regarding hook_entity_operations_alter().
+ *
+ * @group block
+ */
+class BlockHookOperationTest extends WebTestBase {
+
+  /**
+   * Modules to install.
+   *
+   * @var array
+   */
+  public static $modules = array('block', 'entity_test');
+
+  protected function setUp() {
+    parent::setUp();
+
+    $permissions = array(
+      'administer blocks',
+    );
+
+    // Create and log in user.
+    $admin_user = $this->drupalCreateUser($permissions);
+    $this->drupalLogin($admin_user);
+  }
+
+  /**
+   * Tests the block list to see if the test_operation link is added.
+   */
+  public function testBlockOperationAlter() {
+    // Add a test block, any block will do.
+    // Set the machine name so the test_operation link can be built later.
+    $block_id = Unicode::strtolower($this->randomMachineName(16));
+    $this->drupalPlaceBlock('system_powered_by_block', array('id' => $block_id));
+
+    // Get the Block listing.
+    $this->drupalGet('admin/structure/block');
+
+    $test_operation_link = 'admin/structure/block/manage/' . $block_id . '/test_operation';
+    // Test if the test_operation link is on the page.
+    $this->assertLinkByHref($test_operation_link);
+  }
+
+}

web/core/modules/block/src/Tests/BlockHtmlTest.php

@@ -0,0 +1,50 @@
+<?php
+
+namespace Drupal\block\Tests;
+
+use Drupal\simpletest\WebTestBase;
+
+/**
+ * Tests block HTML ID validity.
+ *
+ * @group block
+ */
+class BlockHtmlTest extends WebTestBase {
+
+  /**
+   * Modules to install.
+   *
+   * @var array
+   */
+  public static $modules = array('block', 'block_test');
+
+  protected function setUp() {
+    parent::setUp();
+
+    $this->drupalLogin($this->rootUser);
+
+    // Enable the test_html block, to test HTML ID and attributes.
+    \Drupal::state()->set('block_test.attributes', array('data-custom-attribute' => 'foo'));
+    \Drupal::state()->set('block_test.content', $this->randomMachineName());
+    $this->drupalPlaceBlock('test_html', array('id' => 'test_html_block'));
+
+    // Enable a menu block, to test more complicated HTML.
+    $this->drupalPlaceBlock('system_menu_block:admin');
+  }
+
+  /**
+   * Tests for valid HTML for a block.
+   */
+  function testHtml() {
+    $this->drupalGet('');
+
+    // Ensure that a block's ID is converted to an HTML valid ID, and that
+    // block-specific attributes are added to the same DOM element.
+    $this->assertFieldByXPath('//div[@id="block-test-html-block" and @data-custom-attribute="foo"]', NULL, 'HTML ID and attributes for test block are valid and on the same DOM element.');
+
+    // Ensure expected markup for a menu block.
+    $elements = $this->xpath('//nav[contains(@class, :nav-class)]/ul[contains(@class, :ul-class)]/li', array(':nav-class' => 'block-menu', ':ul-class' => 'menu'));
+    $this->assertTrue(!empty($elements), 'The proper block markup was found.');
+  }
+
+}

web/core/modules/block/src/Tests/BlockInstallTest.php

@@ -0,0 +1,33 @@
+<?php
+
+namespace Drupal\block\Tests;
+
+use Drupal\simpletest\WebTestBase;
+
+/**
+ * Tests block module's installation.
+ *
+ * @group block
+ */
+class BlockInstallTest extends WebTestBase {
+
+  public function testCacheTagInvalidationUponInstallation() {
+    // Warm the page cache.
+    $this->drupalGet('');
+    $this->assertNoText('Powered by Drupal');
+    $this->assertNoCacheTag('config:block_list');
+
+    // Install the block module, and place the "Powered by Drupal" block.
+    $this->container->get('module_installer')->install(['block', 'shortcut']);
+    $this->rebuildContainer();
+    $this->container->get('router.builder')->rebuild();
+    $this->drupalPlaceBlock('system_powered_by_block');
+
+    // Check the same page, block.module's hook_install() should have
+    // invalidated the 'rendered' cache tag to make blocks show up.
+    $this->drupalGet('');
+    $this->assertCacheTag('config:block_list');
+    $this->assertText('Powered by Drupal');
+  }
+
+}

web/core/modules/block/src/Tests/BlockInvalidRegionTest.php

@@ -0,0 +1,63 @@
+<?php
+
+namespace Drupal\block\Tests;
+
+use Drupal\simpletest\WebTestBase;
+use Drupal\block\Entity\Block;
+
+/**
+ * Tests that an active block assigned to a non-existing region triggers the
+ * warning message and is disabled.
+ *
+ * @group block
+ */
+class BlockInvalidRegionTest extends WebTestBase {
+
+  /**
+   * Modules to install.
+   *
+   * @var array
+   */
+  public static $modules = array('block', 'block_test');
+
+  protected function setUp() {
+    parent::setUp();
+    // Create an admin user.
+    $admin_user = $this->drupalCreateUser(array(
+      'administer site configuration',
+      'access administration pages',
+      'administer blocks',
+    ));
+    $this->drupalLogin($admin_user);
+  }
+
+  /**
+   * Tests that blocks assigned to invalid regions work correctly.
+   */
+  function testBlockInInvalidRegion() {
+    // Enable a test block and place it in an invalid region.
+    $block = $this->drupalPlaceBlock('test_html');
+    $block->setRegion('invalid_region');
+    $block->save();
+
+    $warning_message = t('The block %info was assigned to the invalid region %region and has been disabled.', array('%info' => $block->id(), '%region' => 'invalid_region'));
+
+    // Clearing the cache should disable the test block placed in the invalid region.
+    $this->drupalPostForm('admin/config/development/performance', array(), 'Clear all caches');
+    $this->assertRaw($warning_message, 'Enabled block was in the invalid region and has been disabled.');
+
+    // Clear the cache to check if the warning message is not triggered.
+    $this->drupalPostForm('admin/config/development/performance', array(), 'Clear all caches');
+    $this->assertNoRaw($warning_message, 'Disabled block in the invalid region will not trigger the warning.');
+
+    // Place disabled test block in the invalid region of the default theme.
+    $block = Block::load($block->id());
+    $block->setRegion('invalid_region');
+    $block->save();
+
+    // Clear the cache to check if the warning message is not triggered.
+    $this->drupalPostForm('admin/config/development/performance', array(), 'Clear all caches');
+    $this->assertNoRaw($warning_message, 'Disabled block in the invalid region will not trigger the warning.');
+  }
+
+}

web/core/modules/block/src/Tests/BlockLanguageCacheTest.php

@@ -0,0 +1,77 @@
+<?php
+
+namespace Drupal\block\Tests;
+
+use Drupal\Component\Utility\Unicode;
+use Drupal\language\Entity\ConfigurableLanguage;
+use Drupal\simpletest\WebTestBase;
+
+/**
+ * Tests display of menu blocks with multiple languages.
+ *
+ * @group block
+ */
+class BlockLanguageCacheTest extends WebTestBase {
+
+  /**
+   * Modules to install.
+   *
+   * @var array
+   */
+  public static $modules = array('block', 'language', 'menu_ui');
+
+  /**
+   * List of langcodes.
+   *
+   * @var array
+   */
+  protected $langcodes = array();
+
+  protected function setUp() {
+    parent::setUp();
+
+    // Create test languages.
+    $this->langcodes = array(ConfigurableLanguage::load('en'));
+    for ($i = 1; $i < 3; ++$i) {
+      $language = ConfigurableLanguage::create(array(
+        'id' => 'l' . $i,
+        'label' => $this->randomString(),
+      ));
+      $language->save();
+      $this->langcodes[$i] = $language;
+    }
+  }
+
+  /**
+   * Creates a block in a language, check blocks page in all languages.
+   */
+  public function testBlockLinks() {
+    // Create admin user to be able to access block admin.
+    $admin_user = $this->drupalCreateUser(array(
+      'administer blocks',
+      'access administration pages',
+      'administer menu',
+    ));
+    $this->drupalLogin($admin_user);
+
+    // Create the block cache for all languages.
+    foreach ($this->langcodes as $langcode) {
+      $this->drupalGet('admin/structure/block', array('language' => $langcode));
+      $this->clickLinkPartialName('Place block');
+    }
+
+    // Create a menu in the default language.
+    $edit['label'] = $this->randomMachineName();
+    $edit['id'] = Unicode::strtolower($edit['label']);
+    $this->drupalPostForm('admin/structure/menu/add', $edit, t('Save'));
+    $this->assertText(t('Menu @label has been added.', array('@label' => $edit['label'])));
+
+    // Check that the block is listed for all languages.
+    foreach ($this->langcodes as $langcode) {
+      $this->drupalGet('admin/structure/block', array('language' => $langcode));
+      $this->clickLinkPartialName('Place block');
+      $this->assertText($edit['label']);
+    }
+  }
+
+}

web/core/modules/block/src/Tests/BlockLanguageTest.php

@@ -0,0 +1,185 @@
+<?php
+
+namespace Drupal\block\Tests;
+
+use Drupal\simpletest\WebTestBase;
+use Drupal\block\Entity\Block;
+
+/**
+ * Tests if a block can be configured to be only visible on a particular
+ * language.
+ *
+ * @group block
+ */
+class BlockLanguageTest extends WebTestBase {
+
+  /**
+   * An administrative user to configure the test environment.
+   */
+  protected $adminUser;
+
+  /**
+   * Modules to install.
+   *
+   * @var array
+   */
+  public static $modules = array('language', 'block', 'content_translation');
+
+  protected function setUp() {
+    parent::setUp();
+
+    // Create a new user, allow him to manage the blocks and the languages.
+    $this->adminUser = $this->drupalCreateUser(array('administer blocks', 'administer languages'));
+    $this->drupalLogin($this->adminUser);
+
+    // Add predefined language.
+    $edit = array(
+      'predefined_langcode' => 'fr',
+    );
+    $this->drupalPostForm('admin/config/regional/language/add', $edit, t('Add language'));
+    $this->assertText('French', 'Language added successfully.');
+  }
+
+  /**
+   * Tests the visibility settings for the blocks based on language.
+   */
+  public function testLanguageBlockVisibility() {
+    // Check if the visibility setting is available.
+    $default_theme = $this->config('system.theme')->get('default');
+    $this->drupalGet('admin/structure/block/add/system_powered_by_block' . '/' . $default_theme);
+
+    $this->assertField('visibility[language][langcodes][en]', 'Language visibility field is visible.');
+    $this->assertNoField('visibility[language][context_mapping][language]', 'Language type field is not visible.');
+
+    // Enable a standard block and set the visibility setting for one language.
+    $edit = array(
+      'visibility[language][langcodes][en]' => TRUE,
+      'id' => strtolower($this->randomMachineName(8)),
+      'region' => 'sidebar_first',
+    );
+    $this->drupalPostForm('admin/structure/block/add/system_powered_by_block' . '/' . $default_theme, $edit, t('Save block'));
+
+    // Change the default language.
+    $edit = array(
+      'site_default_language' => 'fr',
+    );
+    $this->drupalPostForm('admin/config/regional/language', $edit, t('Save configuration'));
+
+    // Check that a page has a block.
+    $this->drupalGet('en');
+    $this->assertText('Powered by Drupal', 'The body of the custom block appears on the page.');
+
+    // Check that a page doesn't has a block for the current language anymore.
+    $this->drupalGet('fr');
+    $this->assertNoText('Powered by Drupal', 'The body of the custom block does not appear on the page.');
+  }
+
+  /**
+   * Tests if the visibility settings are removed if the language is deleted.
+   */
+  public function testLanguageBlockVisibilityLanguageDelete() {
+    // Enable a standard block and set the visibility setting for one language.
+    $edit = array(
+      'visibility' => array(
+        'language' => array(
+          'langcodes' => array(
+            'fr' => 'fr',
+          ),
+          'context_mapping' => ['language' => '@language.current_language_context:language_interface'],
+        ),
+      ),
+    );
+    $block = $this->drupalPlaceBlock('system_powered_by_block', $edit);
+
+    // Check that we have the language in config after saving the setting.
+    $visibility = $block->getVisibility();
+    $this->assertEqual('fr', $visibility['language']['langcodes']['fr'], 'Language is set in the block configuration.');
+
+    // Delete the language.
+    $this->drupalPostForm('admin/config/regional/language/delete/fr', array(), t('Delete'));
+
+    // Check that the language is no longer stored in the configuration after
+    // it is deleted.
+    $block = Block::load($block->id());
+    $visibility = $block->getVisibility();
+    $this->assertTrue(empty($visibility['language']['langcodes']['fr']), 'Language is no longer not set in the block configuration after deleting the block.');
+
+    // Ensure that the block visibility for language is gone from the UI.
+    $this->drupalGet('admin/structure/block');
+    $this->clickLink('Configure');
+    $elements = $this->xpath('//details[@id="edit-visibility-language"]');
+    $this->assertTrue(empty($elements));
+  }
+
+  /**
+   * Tests block language visibility with different language types.
+   */
+  public function testMultipleLanguageTypes() {
+    // Customize content language detection to be different from interface
+    // language detection.
+    $edit = [
+      // Interface language detection: only using session.
+      'language_interface[enabled][language-url]' => FALSE,
+      'language_interface[enabled][language-session]' => TRUE,
+      // Content language detection: only using URL.
+      'language_content[configurable]' => TRUE,
+      'language_content[enabled][language-url]' => TRUE,
+      'language_content[enabled][language-interface]' => FALSE,
+    ];
+    $this->drupalPostForm('admin/config/regional/language/detection', $edit, t('Save settings'));
+
+    // Check if the visibility setting is available with a type setting.
+    $default_theme = $this->config('system.theme')->get('default');
+    $this->drupalGet('admin/structure/block/add/system_powered_by_block' . '/' . $default_theme);
+    $this->assertField('visibility[language][langcodes][en]', 'Language visibility field is visible.');
+    $this->assertField('visibility[language][context_mapping][language]', 'Language type field is visible.');
+
+    // Enable a standard block and set visibility to French only.
+    $block_id = strtolower($this->randomMachineName(8));
+    $edit = [
+      'visibility[language][context_mapping][language]' => '@language.current_language_context:language_interface',
+      'visibility[language][langcodes][fr]' => TRUE,
+      'id' => $block_id,
+      'region' => 'sidebar_first',
+    ];
+    $this->drupalPostForm('admin/structure/block/add/system_powered_by_block' . '/' . $default_theme, $edit, t('Save block'));
+
+    // Interface negotiation depends on request arguments.
+    $this->drupalGet('node', ['query' => ['language' => 'en']]);
+    $this->assertNoText('Powered by Drupal', 'The body of the block does not appear on the page.');
+    $this->drupalGet('node', ['query' => ['language' => 'fr']]);
+    $this->assertText('Powered by Drupal', 'The body of the block appears on the page.');
+
+    // Log in again in order to clear the interface language stored in the
+    // session.
+    $this->drupalLogout();
+    $this->drupalLogin($this->adminUser);
+
+    // Content language does not depend on session/request arguments.
+    // It will fall back on English (site default) and not display the block.
+    $this->drupalGet('en');
+    $this->assertNoText('Powered by Drupal', 'The body of the block does not appear on the page.');
+    $this->drupalGet('fr');
+    $this->assertNoText('Powered by Drupal', 'The body of the block does not appear on the page.');
+
+    // Change visibility to now depend on content language for this block.
+    $edit = [
+      'visibility[language][context_mapping][language]' => '@language.current_language_context:language_content'
+    ];
+    $this->drupalPostForm('admin/structure/block/manage/' . $block_id, $edit, t('Save block'));
+
+    // Content language negotiation does not depend on request arguments.
+    // It will fall back on English (site default) and not display the block.
+    $this->drupalGet('node', ['query' => ['language' => 'en']]);
+    $this->assertNoText('Powered by Drupal', 'The body of the block does not appear on the page.');
+    $this->drupalGet('node', ['query' => ['language' => 'fr']]);
+    $this->assertNoText('Powered by Drupal', 'The body of the block does not appear on the page.');
+
+    // Content language negotiation depends on path prefix.
+    $this->drupalGet('en');
+    $this->assertNoText('Powered by Drupal', 'The body of the block does not appear on the page.');
+    $this->drupalGet('fr');
+    $this->assertText('Powered by Drupal', 'The body of the block appears on the page.');
+  }
+
+}

web/core/modules/block/src/Tests/BlockRenderOrderTest.php

@@ -0,0 +1,80 @@
+<?php
+
+namespace Drupal\block\Tests;
+
+use Drupal\Component\Utility\Html;
+use Drupal\simpletest\WebTestBase;
+
+/**
+ * Tests blocks are being rendered in order by weight.
+ *
+ * @group block
+ */
+class BlockRenderOrderTest extends WebTestBase {
+
+  /**
+   * Modules to install.
+   *
+   * @var array
+   */
+  public static $modules = array('node', 'block');
+
+  protected function setUp() {
+    parent::setUp();
+    // Create a test user.
+    $end_user = $this->drupalCreateUser(array(
+      'access content',
+    ));
+    $this->drupalLogin($end_user);
+  }
+
+  /**
+   * Tests the render order of the blocks.
+   */
+  function testBlockRenderOrder() {
+    // Enable test blocks and place them in the same region.
+    $region = 'header';
+    $test_blocks = array(
+      'stark_powered' => array(
+        'weight' => '-3',
+        'id' => 'stark_powered',
+        'label' => 'Test block A',
+      ),
+      'stark_by' => array(
+        'weight' => '3',
+        'id' => 'stark_by',
+        'label' => 'Test block C',
+      ),
+      'stark_drupal' => array(
+        'weight' => '3',
+        'id' => 'stark_drupal',
+        'label' => 'Test block B',
+      ),
+    );
+
+    // Place the test blocks.
+    foreach ($test_blocks as $test_block) {
+      $this->drupalPlaceBlock('system_powered_by_block', array(
+        'label' => $test_block['label'],
+        'region' => $region,
+        'weight' => $test_block['weight'],
+        'id' => $test_block['id'],
+      ));
+    }
+
+    $this->drupalGet('');
+    $test_content = $this->getRawContent('');
+
+    $controller = $this->container->get('entity_type.manager')->getStorage('block');
+    foreach ($controller->loadMultiple() as $return_block) {
+      $id = $return_block->id();
+      if ($return_block_weight = $return_block->getWeight()) {
+        $this->assertTrue($test_blocks[$id]['weight'] == $return_block_weight, 'Block weight is set as "' . $return_block_weight . '" for ' . $id . ' block.');
+        $position[$id] = strpos($test_content, Html::getClass('block-' . $test_blocks[$id]['id']));
+      }
+    }
+    $this->assertTrue($position['stark_powered'] < $position['stark_by'], 'Blocks with different weight are rendered in the correct order.');
+    $this->assertTrue($position['stark_drupal'] < $position['stark_by'], 'Blocks with identical weight are rendered in alphabetical order.');
+  }
+
+}

web/core/modules/block/src/Tests/BlockSystemBrandingTest.php

@@ -0,0 +1,119 @@
+<?php
+
+namespace Drupal\block\Tests;
+
+/**
+ * Tests branding block display.
+ *
+ * @group block
+ */
+class BlockSystemBrandingTest extends BlockTestBase {
+
+  /**
+   * Modules to install.
+   *
+   * @var array
+   */
+  public static $modules = array('block', 'system');
+
+  /**
+   * {@inheritdoc}
+   */
+  protected function setUp() {
+    parent::setUp();
+    // Set a site slogan.
+    $this->config('system.site')
+      ->set('slogan', 'Community plumbing')
+      ->save();
+    // Add the system branding block to the page.
+    $this->drupalPlaceBlock('system_branding_block', array('region' => 'header', 'id' => 'site-branding'));
+  }
+
+  /**
+   * Tests system branding block configuration.
+   */
+  public function testSystemBrandingSettings() {
+    $site_logo_xpath = '//div[@id="block-site-branding"]//a[@class="site-logo"]';
+    $site_name_xpath = '//div[@id="block-site-branding"]//div[@class="site-name"]';
+    $site_slogan_xpath = '//div[@id="block-site-branding"]//div[@class="site-slogan"]';
+
+    // Set default block settings.
+    $this->drupalGet('');
+    $site_logo_element = $this->xpath($site_logo_xpath);
+    $site_name_element = $this->xpath($site_name_xpath);
+    $site_slogan_element = $this->xpath($site_slogan_xpath);
+    // Test that all branding elements are displayed.
+    $this->assertTrue(!empty($site_logo_element), 'The branding block logo was found.');
+    $this->assertTrue(!empty($site_name_element), 'The branding block site name was found.');
+    $this->assertTrue(!empty($site_slogan_element), 'The branding block slogan was found.');
+    $this->assertCacheTag('config:system.site');
+
+    // Be sure the slogan is XSS-filtered.
+    $this->config('system.site')
+      ->set('slogan', '<script>alert("Community carpentry");</script>')
+      ->save();
+    $this->drupalGet('');
+    $site_slogan_element = $this->xpath($site_slogan_xpath);
+    $this->assertEqual($site_slogan_element[0], 'alert("Community carpentry");', 'The site slogan was XSS-filtered.');
+
+    // Turn just the logo off.
+    $this->config('block.block.site-branding')
+      ->set('settings.use_site_logo', 0)
+      ->save();
+    $this->drupalGet('');
+    $site_logo_element = $this->xpath($site_logo_xpath);
+    $site_name_element = $this->xpath($site_name_xpath);
+    $site_slogan_element = $this->xpath($site_slogan_xpath);
+    // Re-test all branding elements.
+    $this->assertTrue(empty($site_logo_element), 'The branding block logo was disabled.');
+    $this->assertTrue(!empty($site_name_element), 'The branding block site name was found.');
+    $this->assertTrue(!empty($site_slogan_element), 'The branding block slogan was found.');
+    $this->assertCacheTag('config:system.site');
+
+    // Turn just the site name off.
+    $this->config('block.block.site-branding')
+      ->set('settings.use_site_logo', 1)
+      ->set('settings.use_site_name', 0)
+      ->save();
+    $this->drupalGet('');
+    $site_logo_element = $this->xpath($site_logo_xpath);
+    $site_name_element = $this->xpath($site_name_xpath);
+    $site_slogan_element = $this->xpath($site_slogan_xpath);
+    // Re-test all branding elements.
+    $this->assertTrue(!empty($site_logo_element), 'The branding block logo was found.');
+    $this->assertTrue(empty($site_name_element), 'The branding block site name was disabled.');
+    $this->assertTrue(!empty($site_slogan_element), 'The branding block slogan was found.');
+    $this->assertCacheTag('config:system.site');
+
+    // Turn just the site slogan off.
+    $this->config('block.block.site-branding')
+      ->set('settings.use_site_name', 1)
+      ->set('settings.use_site_slogan', 0)
+      ->save();
+    $this->drupalGet('');
+    $site_logo_element = $this->xpath($site_logo_xpath);
+    $site_name_element = $this->xpath($site_name_xpath);
+    $site_slogan_element = $this->xpath($site_slogan_xpath);
+    // Re-test all branding elements.
+    $this->assertTrue(!empty($site_logo_element), 'The branding block logo was found.');
+    $this->assertTrue(!empty($site_name_element), 'The branding block site name was found.');
+    $this->assertTrue(empty($site_slogan_element), 'The branding block slogan was disabled.');
+    $this->assertCacheTag('config:system.site');
+
+    // Turn the site name and the site slogan off.
+    $this->config('block.block.site-branding')
+      ->set('settings.use_site_name', 0)
+      ->set('settings.use_site_slogan', 0)
+      ->save();
+    $this->drupalGet('');
+    $site_logo_element = $this->xpath($site_logo_xpath);
+    $site_name_element = $this->xpath($site_name_xpath);
+    $site_slogan_element = $this->xpath($site_slogan_xpath);
+    // Re-test all branding elements.
+    $this->assertTrue(!empty($site_logo_element), 'The branding block logo was found.');
+    $this->assertTrue(empty($site_name_element), 'The branding block site name was disabled.');
+    $this->assertTrue(empty($site_slogan_element), 'The branding block slogan was disabled.');
+    $this->assertCacheTag('config:system.site');
+  }
+
+}

web/core/modules/block/src/Tests/BlockTemplateSuggestionsTest.php

@@ -0,0 +1,48 @@
+<?php
+
+namespace Drupal\block\Tests;
+
+use Drupal\block\Entity\Block;
+use Drupal\simpletest\WebTestBase;
+
+/**
+ * Tests the block_theme_suggestions_block() function.
+ *
+ * @group block
+ */
+class BlockTemplateSuggestionsTest extends WebTestBase {
+
+  /**
+   * Modules to install.
+   *
+   * @var array
+   */
+  public static $modules = array('block');
+
+  /**
+   * Tests template suggestions from block_theme_suggestions_block().
+   */
+  function testBlockThemeHookSuggestions() {
+    // Define a block with a derivative to be preprocessed, which includes both
+    // an underscore (not transformed) and a hyphen (transformed to underscore),
+    // and generates possibilities for each level of derivative.
+    // @todo Clarify this comment.
+    $block = Block::create(array(
+      'plugin' => 'system_menu_block:admin',
+      'region' => 'footer',
+      'id' => 'machinename',
+    ));
+
+    $variables = array();
+    $plugin = $block->getPlugin();
+    $variables['elements']['#configuration'] = $plugin->getConfiguration();
+    $variables['elements']['#plugin_id'] = $plugin->getPluginId();
+    $variables['elements']['#id'] = $block->id();
+    $variables['elements']['#base_plugin_id'] = $plugin->getBaseId();
+    $variables['elements']['#derivative_plugin_id'] = $plugin->getDerivativeId();
+    $variables['elements']['content'] = array();
+    $suggestions = block_theme_suggestions_block($variables);
+    $this->assertEqual($suggestions, array('block__system', 'block__system_menu_block', 'block__system_menu_block__admin', 'block__machinename'));
+  }
+
+}

web/core/modules/block/src/Tests/BlockTest.php

@@ -0,0 +1,546 @@
+<?php
+
+namespace Drupal\block\Tests;
+
+use Drupal\Component\Utility\Html;
+use Drupal\block\Entity\Block;
+use Drupal\Core\Url;
+use Drupal\user\Entity\Role;
+use Drupal\user\RoleInterface;
+
+/**
+ * Tests basic block functionality.
+ *
+ * @group block
+ */
+class BlockTest extends BlockTestBase {
+
+  /**
+   * Tests block visibility.
+   */
+  function testBlockVisibility() {
+    $block_name = 'system_powered_by_block';
+    // Create a random title for the block.
+    $title = $this->randomMachineName(8);
+    // Enable a standard block.
+    $default_theme = $this->config('system.theme')->get('default');
+    $edit = array(
+      'id' => strtolower($this->randomMachineName(8)),
+      'region' => 'sidebar_first',
+      'settings[label]' => $title,
+      'settings[label_display]' => TRUE,
+    );
+    // Set the block to be hidden on any user path, and to be shown only to
+    // authenticated users.
+    $edit['visibility[request_path][pages]'] = '/user*';
+    $edit['visibility[request_path][negate]'] = TRUE;
+    $edit['visibility[user_role][roles][' . RoleInterface::AUTHENTICATED_ID . ']'] = TRUE;
+    $this->drupalGet('admin/structure/block/add/' . $block_name . '/' . $default_theme);
+    $this->assertFieldChecked('edit-visibility-request-path-negate-0');
+
+    $this->drupalPostForm(NULL, $edit, t('Save block'));
+    $this->assertText('The block configuration has been saved.', 'Block was saved');
+
+    $this->clickLink('Configure');
+    $this->assertFieldChecked('edit-visibility-request-path-negate-1');
+
+    $this->drupalGet('');
+    $this->assertText($title, 'Block was displayed on the front page.');
+
+    $this->drupalGet('user');
+    $this->assertNoText($title, 'Block was not displayed according to block visibility rules.');
+
+    // Confirm that the block is not displayed to anonymous users.
+    $this->drupalLogout();
+    $this->drupalGet('');
+    $this->assertNoText($title, 'Block was not displayed to anonymous users.');
+
+    // Confirm that an empty block is not displayed.
+    $this->assertNoText('Powered by Drupal', 'Empty block not displayed.');
+    $this->assertNoRaw('sidebar-first', 'Empty sidebar-first region is not displayed.');
+  }
+
+  /**
+   * Tests that visibility can be properly toggled.
+   */
+  public function testBlockToggleVisibility() {
+    $block_name = 'system_powered_by_block';
+    // Create a random title for the block.
+    $title = $this->randomMachineName(8);
+    // Enable a standard block.
+    $default_theme = $this->config('system.theme')->get('default');
+    $edit = array(
+      'id' => strtolower($this->randomMachineName(8)),
+      'region' => 'sidebar_first',
+      'settings[label]' => $title,
+    );
+    $block_id = $edit['id'];
+    // Set the block to be shown only to authenticated users.
+    $edit['visibility[user_role][roles][' . RoleInterface::AUTHENTICATED_ID . ']'] = TRUE;
+    $this->drupalPostForm('admin/structure/block/add/' . $block_name . '/' . $default_theme, $edit, t('Save block'));
+    $this->clickLink('Configure');
+    $this->assertFieldChecked('edit-visibility-user-role-roles-authenticated');
+
+    $edit = [
+      'visibility[user_role][roles][' . RoleInterface::AUTHENTICATED_ID . ']' => FALSE,
+    ];
+    $this->drupalPostForm(NULL, $edit, 'Save block');
+    $this->clickLink('Configure');
+    $this->assertNoFieldChecked('edit-visibility-user-role-roles-authenticated');
+
+    // Ensure that no visibility is configured.
+    /** @var \Drupal\block\BlockInterface $block */
+    $block = Block::load($block_id);
+    $visibility_config = $block->getVisibilityConditions()->getConfiguration();
+    $this->assertIdentical([], $visibility_config);
+    $this->assertIdentical([], $block->get('visibility'));
+  }
+
+  /**
+   * Test block visibility when leaving "pages" textarea empty.
+   */
+  function testBlockVisibilityListedEmpty() {
+    $block_name = 'system_powered_by_block';
+    // Create a random title for the block.
+    $title = $this->randomMachineName(8);
+    // Enable a standard block.
+    $default_theme = $this->config('system.theme')->get('default');
+    $edit = array(
+      'id' => strtolower($this->randomMachineName(8)),
+      'region' => 'sidebar_first',
+      'settings[label]' => $title,
+      'visibility[request_path][negate]' => TRUE,
+    );
+    // Set the block to be hidden on any user path, and to be shown only to
+    // authenticated users.
+    $this->drupalPostForm('admin/structure/block/add/' . $block_name . '/' . $default_theme, $edit, t('Save block'));
+    $this->assertText('The block configuration has been saved.', 'Block was saved');
+
+    $this->drupalGet('user');
+    $this->assertNoText($title, 'Block was not displayed according to block visibility rules.');
+
+    $this->drupalGet('USER');
+    $this->assertNoText($title, 'Block was not displayed according to block visibility rules regardless of path case.');
+
+    // Confirm that the block is not displayed to anonymous users.
+    $this->drupalLogout();
+    $this->drupalGet('');
+    $this->assertNoText($title, 'Block was not displayed to anonymous users on the front page.');
+  }
+
+  /**
+   * Tests adding a block from the library page with a weight query string.
+   */
+  public function testAddBlockFromLibraryWithWeight() {
+    $default_theme = $this->config('system.theme')->get('default');
+    // Test one positive, zero, and one negative weight.
+    foreach (['7', '0', '-9'] as $weight) {
+      $options = [
+        'query' => [
+          'region' => 'sidebar_first',
+          'weight' => $weight,
+        ],
+      ];
+      $this->drupalGet(Url::fromRoute('block.admin_library', ['theme' => $default_theme], $options));
+
+      $block_name = 'system_powered_by_block';
+      $add_url = Url::fromRoute('block.admin_add', [
+        'plugin_id' => $block_name,
+        'theme' => $default_theme
+      ]);
+      $links = $this->xpath('//a[contains(@href, :href)]', [':href' => $add_url->toString()]);
+      $this->assertEqual(1, count($links), 'Found one matching link.');
+      $this->assertEqual(t('Place block'), (string) $links[0], 'Found the expected link text.');
+
+      list($path, $query_string) = explode('?', $links[0]['href'], 2);
+      parse_str($query_string, $query_parts);
+      $this->assertEqual($weight, $query_parts['weight'], 'Found the expected weight query string.');
+
+      // Create a random title for the block.
+      $title = $this->randomMachineName(8);
+      $block_id = strtolower($this->randomMachineName(8));
+      $edit = [
+        'id' => $block_id,
+        'settings[label]' => $title,
+      ];
+      // Create the block using the link parsed from the library page.
+      $this->drupalPostForm($this->getAbsoluteUrl($links[0]['href']), $edit, t('Save block'));
+
+      // Ensure that the block was created with the expected weight.
+      /** @var \Drupal\block\BlockInterface $block */
+      $block = Block::load($block_id);
+      $this->assertEqual($weight, $block->getWeight(), 'Found the block with expected weight.');
+    }
+  }
+
+  /**
+   * Test configuring and moving a module-define block to specific regions.
+   */
+  function testBlock() {
+    // Place page title block to test error messages.
+    $this->drupalPlaceBlock('page_title_block');
+
+    // Select the 'Powered by Drupal' block to be configured and moved.
+    $block = array();
+    $block['id'] = 'system_powered_by_block';
+    $block['settings[label]'] = $this->randomMachineName(8);
+    $block['settings[label_display]'] = TRUE;
+    $block['theme'] = $this->config('system.theme')->get('default');
+    $block['region'] = 'header';
+
+    // Set block title to confirm that interface works and override any custom titles.
+    $this->drupalPostForm('admin/structure/block/add/' . $block['id'] . '/' . $block['theme'], array('settings[label]' => $block['settings[label]'], 'settings[label_display]' => $block['settings[label_display]'], 'id' => $block['id'], 'region' => $block['region']), t('Save block'));
+    $this->assertText(t('The block configuration has been saved.'), 'Block title set.');
+    // Check to see if the block was created by checking its configuration.
+    $instance = Block::load($block['id']);
+
+    $this->assertEqual($instance->label(), $block['settings[label]'], 'Stored block title found.');
+
+    // Check whether the block can be moved to all available regions.
+    foreach ($this->regions as $region) {
+      $this->moveBlockToRegion($block, $region);
+    }
+
+    // Set the block to the disabled region.
+    $edit = array();
+    $edit['blocks[' . $block['id'] . '][region]'] = -1;
+    $this->drupalPostForm('admin/structure/block', $edit, t('Save blocks'));
+
+    // Confirm that the block is now listed as disabled.
+    $this->assertText(t('The block settings have been updated.'), 'Block successfully move to disabled region.');
+
+    // Confirm that the block instance title and markup are not displayed.
+    $this->drupalGet('node');
+    $this->assertNoText(t($block['settings[label]']));
+    // Check for <div id="block-my-block-instance-name"> if the machine name
+    // is my_block_instance_name.
+    $xpath = $this->buildXPathQuery('//div[@id=:id]/*', array(':id' => 'block-' . str_replace('_', '-', strtolower($block['id']))));
+    $this->assertNoFieldByXPath($xpath, FALSE, 'Block found in no regions.');
+
+    // Test deleting the block from the edit form.
+    $this->drupalGet('admin/structure/block/manage/' . $block['id']);
+    $this->clickLink(t('Delete'));
+    $this->assertRaw(t('Are you sure you want to delete the block %name?', array('%name' => $block['settings[label]'])));
+    $this->drupalPostForm(NULL, array(), t('Delete'));
+    $this->assertRaw(t('The block %name has been deleted.', array('%name' => $block['settings[label]'])));
+
+    // Test deleting a block via "Configure block" link.
+    $block = $this->drupalPlaceBlock('system_powered_by_block');
+    $this->drupalGet('admin/structure/block/manage/' . $block->id(), array('query' => array('destination' => 'admin')));
+    $this->clickLink(t('Delete'));
+    $this->assertRaw(t('Are you sure you want to delete the block %name?', array('%name' => $block->label())));
+    $this->drupalPostForm(NULL, array(), t('Delete'));
+    $this->assertRaw(t('The block %name has been deleted.', array('%name' => $block->label())));
+    $this->assertUrl('admin');
+    $this->assertNoRaw($block->id());
+  }
+
+  /**
+   * Tests that the block form has a theme selector when not passed via the URL.
+   */
+  public function testBlockThemeSelector() {
+    // Install all themes.
+    \Drupal::service('theme_handler')->install(['bartik', 'seven', 'stark']);
+    $theme_settings = $this->config('system.theme');
+    foreach (['bartik', 'seven', 'stark'] as $theme) {
+      $this->drupalGet('admin/structure/block/list/' . $theme);
+      $this->assertTitle(t('Block layout') . ' | Drupal');
+      // Select the 'Powered by Drupal' block to be placed.
+      $block = array();
+      $block['id'] = strtolower($this->randomMachineName());
+      $block['theme'] = $theme;
+      $block['region'] = 'content';
+      $this->drupalPostForm('admin/structure/block/add/system_powered_by_block', $block, t('Save block'));
+      $this->assertText(t('The block configuration has been saved.'));
+      $this->assertUrl('admin/structure/block/list/' . $theme . '?block-placement=' . Html::getClass($block['id']));
+
+      // Set the default theme and ensure the block is placed.
+      $theme_settings->set('default', $theme)->save();
+      $this->drupalGet('');
+      $elements = $this->xpath('//div[@id = :id]', array(':id' => Html::getUniqueId('block-' . $block['id'])));
+      $this->assertTrue(!empty($elements), 'The block was found.');
+    }
+  }
+
+  /**
+   * Test block display of theme titles.
+   */
+  function testThemeName() {
+    // Enable the help block.
+    $this->drupalPlaceBlock('help_block', array('region' => 'help'));
+    $this->drupalPlaceBlock('local_tasks_block');
+    // Explicitly set the default and admin themes.
+    $theme = 'block_test_specialchars_theme';
+    \Drupal::service('theme_handler')->install(array($theme));
+    \Drupal::service('router.builder')->rebuild();
+    $this->drupalGet('admin/structure/block');
+    $this->assertEscaped('<"Cat" & \'Mouse\'>');
+    $this->drupalGet('admin/structure/block/list/block_test_specialchars_theme');
+    $this->assertEscaped('Demonstrate block regions (<"Cat" & \'Mouse\'>)');
+  }
+
+  /**
+   * Test block title display settings.
+   */
+  function testHideBlockTitle() {
+    $block_name = 'system_powered_by_block';
+    // Create a random title for the block.
+    $title = $this->randomMachineName(8);
+    $id = strtolower($this->randomMachineName(8));
+    // Enable a standard block.
+    $default_theme = $this->config('system.theme')->get('default');
+    $edit = array(
+      'id' => $id,
+      'region' => 'sidebar_first',
+      'settings[label]' => $title,
+    );
+    $this->drupalPostForm('admin/structure/block/add/' . $block_name . '/' . $default_theme, $edit, t('Save block'));
+    $this->assertText('The block configuration has been saved.', 'Block was saved');
+
+    $this->drupalGet('user');
+    $this->assertNoText($title, 'Block title was not displayed by default.');
+
+    $edit = array(
+      'settings[label_display]' => TRUE,
+    );
+    $this->drupalPostForm('admin/structure/block/manage/' . $id, $edit, t('Save block'));
+    $this->assertText('The block configuration has been saved.', 'Block was saved');
+
+    $this->drupalGet('admin/structure/block/manage/' . $id);
+    $this->assertFieldChecked('edit-settings-label-display', 'The display_block option has the correct default value on the configuration form.');
+
+    $this->drupalGet('user');
+    $this->assertText($title, 'Block title was displayed when enabled.');
+  }
+
+  /**
+   * Moves a block to a given region via the UI and confirms the result.
+   *
+   * @param array $block
+   *   An array of information about the block, including the following keys:
+   *   - module: The module providing the block.
+   *   - title: The title of the block.
+   *   - delta: The block's delta key.
+   * @param string $region
+   *   The machine name of the theme region to move the block to, for example
+   *   'header' or 'sidebar_first'.
+   */
+  function moveBlockToRegion(array $block, $region) {
+    // Set the created block to a specific region.
+    $block += array('theme' => $this->config('system.theme')->get('default'));
+    $edit = array();
+    $edit['blocks[' . $block['id'] . '][region]'] = $region;
+    $this->drupalPostForm('admin/structure/block', $edit, t('Save blocks'));
+
+    // Confirm that the block was moved to the proper region.
+    $this->assertText(t('The block settings have been updated.'), format_string('Block successfully moved to %region_name region.', array( '%region_name' => $region)));
+
+    // Confirm that the block is being displayed.
+    $this->drupalGet('');
+    $this->assertText(t($block['settings[label]']), 'Block successfully being displayed on the page.');
+
+    // Confirm that the custom block was found at the proper region.
+    $xpath = $this->buildXPathQuery('//div[@class=:region-class]//div[@id=:block-id]/*', array(
+      ':region-class' => 'region region-' . Html::getClass($region),
+      ':block-id' => 'block-' . str_replace('_', '-', strtolower($block['id'])),
+    ));
+    $this->assertFieldByXPath($xpath, NULL, t('Block found in %region_name region.', array('%region_name' => Html::getClass($region))));
+  }
+
+  /**
+   * Test that cache tags are properly set and bubbled up to the page cache.
+   *
+   * Verify that invalidation of these cache tags works:
+   * - "block:<block ID>"
+   * - "block_plugin:<block plugin ID>"
+   */
+  public function testBlockCacheTags() {
+    // The page cache only works for anonymous users.
+    $this->drupalLogout();
+
+    // Enable page caching.
+    $config = $this->config('system.performance');
+    $config->set('cache.page.max_age', 300);
+    $config->save();
+
+    // Place the "Powered by Drupal" block.
+    $block = $this->drupalPlaceBlock('system_powered_by_block', array('id' => 'powered'));
+
+    // Prime the page cache.
+    $this->drupalGet('<front>');
+    $this->assertEqual($this->drupalGetHeader('X-Drupal-Cache'), 'MISS');
+
+    // Verify a cache hit, but also the presence of the correct cache tags in
+    // both the page and block caches.
+    $this->drupalGet('<front>');
+    $this->assertEqual($this->drupalGetHeader('X-Drupal-Cache'), 'HIT');
+    $cid_parts = array(\Drupal::url('<front>', array(), array('absolute' => TRUE)), 'html');
+    $cid = implode(':', $cid_parts);
+    $cache_entry = \Drupal::cache('render')->get($cid);
+    $expected_cache_tags = array(
+      'config:block_list',
+      'block_view',
+      'config:block.block.powered',
+      'config:user.role.anonymous',
+      'rendered',
+    );
+    sort($expected_cache_tags);
+    $keys = \Drupal::service('cache_contexts_manager')->convertTokensToKeys(['languages:language_interface', 'theme', 'user.permissions'])->getKeys();
+    $this->assertIdentical($cache_entry->tags, $expected_cache_tags);
+    $cache_entry = \Drupal::cache('render')->get('entity_view:block:powered:' . implode(':', $keys));
+    $expected_cache_tags = array(
+      'block_view',
+      'config:block.block.powered',
+      'rendered',
+    );
+    sort($expected_cache_tags);
+    $this->assertIdentical($cache_entry->tags, $expected_cache_tags);
+
+    // The "Powered by Drupal" block is modified; verify a cache miss.
+    $block->setRegion('content');
+    $block->save();
+    $this->drupalGet('<front>');
+    $this->assertEqual($this->drupalGetHeader('X-Drupal-Cache'), 'MISS');
+
+    // Now we should have a cache hit again.
+    $this->drupalGet('<front>');
+    $this->assertEqual($this->drupalGetHeader('X-Drupal-Cache'), 'HIT');
+
+    // Place the "Powered by Drupal" block another time; verify a cache miss.
+    $block_2 = $this->drupalPlaceBlock('system_powered_by_block', array('id' => 'powered-2'));
+    $this->drupalGet('<front>');
+    $this->assertEqual($this->drupalGetHeader('X-Drupal-Cache'), 'MISS');
+
+    // Verify a cache hit, but also the presence of the correct cache tags.
+    $this->drupalGet('<front>');
+    $this->assertEqual($this->drupalGetHeader('X-Drupal-Cache'), 'HIT');
+    $cid_parts = array(\Drupal::url('<front>', array(), array('absolute' => TRUE)), 'html');
+    $cid = implode(':', $cid_parts);
+    $cache_entry = \Drupal::cache('render')->get($cid);
+    $expected_cache_tags = array(
+      'config:block_list',
+      'block_view',
+      'config:block.block.powered',
+      'config:block.block.powered-2',
+      'config:user.role.anonymous',
+      'rendered',
+    );
+    sort($expected_cache_tags);
+    $this->assertEqual($cache_entry->tags, $expected_cache_tags);
+    $expected_cache_tags = array(
+      'block_view',
+      'config:block.block.powered',
+      'rendered',
+    );
+    sort($expected_cache_tags);
+    $keys = \Drupal::service('cache_contexts_manager')->convertTokensToKeys(['languages:language_interface', 'theme', 'user.permissions'])->getKeys();
+    $cache_entry = \Drupal::cache('render')->get('entity_view:block:powered:' . implode(':', $keys));
+    $this->assertIdentical($cache_entry->tags, $expected_cache_tags);
+    $expected_cache_tags = array(
+      'block_view',
+      'config:block.block.powered-2',
+      'rendered',
+    );
+    sort($expected_cache_tags);
+    $keys = \Drupal::service('cache_contexts_manager')->convertTokensToKeys(['languages:language_interface', 'theme', 'user.permissions'])->getKeys();
+    $cache_entry = \Drupal::cache('render')->get('entity_view:block:powered-2:' . implode(':', $keys));
+    $this->assertIdentical($cache_entry->tags, $expected_cache_tags);
+
+    // Now we should have a cache hit again.
+    $this->drupalGet('<front>');
+    $this->assertEqual($this->drupalGetHeader('X-Drupal-Cache'), 'HIT');
+
+    // Delete the "Powered by Drupal" blocks; verify a cache miss.
+    entity_delete_multiple('block', array('powered', 'powered-2'));
+    $this->drupalGet('<front>');
+    $this->assertEqual($this->drupalGetHeader('X-Drupal-Cache'), 'MISS');
+  }
+
+  /**
+   * Tests that a link exists to block layout from the appearance form.
+   */
+  public function testThemeAdminLink() {
+    $this->drupalPlaceBlock('help_block', ['region' => 'help']);
+    $theme_admin = $this->drupalCreateUser([
+      'administer blocks',
+      'administer themes',
+      'access administration pages',
+    ]);
+    $this->drupalLogin($theme_admin);
+    $this->drupalGet('admin/appearance');
+    $this->assertText('You can place blocks for each theme on the block layout page');
+    $this->assertLinkByHref('admin/structure/block');
+  }
+
+  /**
+   * Tests that uninstalling a theme removes its block configuration.
+   */
+  public function testUninstallTheme() {
+    /** @var \Drupal\Core\Extension\ThemeHandlerInterface $theme_handler */
+    $theme_handler = \Drupal::service('theme_handler');
+
+    $theme_handler->install(['seven']);
+    $theme_handler->setDefault('seven');
+    $block = $this->drupalPlaceBlock('system_powered_by_block', ['theme' => 'seven', 'region' => 'help']);
+    $this->drupalGet('<front>');
+    $this->assertText('Powered by Drupal');
+
+    $theme_handler->setDefault('classy');
+    $theme_handler->uninstall(['seven']);
+
+    // Ensure that the block configuration does not exist anymore.
+    $this->assertIdentical(NULL, Block::load($block->id()));
+  }
+
+  /**
+   * Tests the block access.
+   */
+  public function testBlockAccess() {
+    $this->drupalPlaceBlock('test_access', ['region' => 'help']);
+
+    $this->drupalGet('<front>');
+    $this->assertNoText('Hello test world');
+
+    \Drupal::state()->set('test_block_access', TRUE);
+    $this->drupalGet('<front>');
+    $this->assertText('Hello test world');
+  }
+
+  /**
+   * Tests block_user_role_delete.
+   */
+  public function testBlockUserRoleDelete() {
+    $role1 = Role::create(['id' => 'test_role1', 'name' => $this->randomString()]);
+    $role1->save();
+
+    $role2 = Role::create(['id' => 'test_role2', 'name' => $this->randomString()]);
+    $role2->save();
+
+    $block = Block::create([
+      'id' => $this->randomMachineName(),
+      'plugin' => 'system_powered_by_block',
+    ]);
+
+    $block->setVisibilityConfig('user_role', [
+      'roles' => [
+        $role1->id() => $role1->id(),
+        $role2->id() => $role2->id(),
+      ],
+    ]);
+
+    $block->save();
+
+    $this->assertEqual($block->getVisibility()['user_role']['roles'], [
+      $role1->id() => $role1->id(),
+      $role2->id() => $role2->id()
+    ]);
+
+    $role1->delete();
+
+    $block = Block::load($block->id());
+    $this->assertEqual($block->getVisibility()['user_role']['roles'], [
+      $role2->id() => $role2->id()
+    ]);
+  }
+
+}

web/core/modules/block/src/Tests/BlockTestBase.php

@@ -0,0 +1,71 @@
+<?php
+
+namespace Drupal\block\Tests;
+
+use Drupal\simpletest\WebTestBase;
+use Drupal\filter\Entity\FilterFormat;
+
+/**
+ * Provides setup and helper methods for block module tests.
+ */
+abstract class BlockTestBase extends WebTestBase {
+
+  /**
+   * Modules to install.
+   *
+   * @var array
+   */
+  public static $modules = array('block', 'filter', 'test_page_test', 'help', 'block_test');
+
+  /**
+   * A list of theme regions to test.
+   *
+   * @var array
+   */
+  protected $regions;
+
+  /**
+   * A test user with administrative privileges.
+   *
+   * @var \Drupal\user\UserInterface
+   */
+  protected $adminUser;
+
+  protected function setUp() {
+    parent::setUp();
+
+    // Use the test page as the front page.
+    $this->config('system.site')->set('page.front', '/test-page')->save();
+
+    // Create Full HTML text format.
+    $full_html_format = FilterFormat::create(array(
+      'format' => 'full_html',
+      'name' => 'Full HTML',
+    ));
+    $full_html_format->save();
+
+    // Create and log in an administrative user having access to the Full HTML
+    // text format.
+    $this->adminUser = $this->drupalCreateUser(array(
+      'administer blocks',
+      $full_html_format->getPermissionName(),
+      'access administration pages',
+    ));
+    $this->drupalLogin($this->adminUser);
+
+    // Define the existing regions.
+    $this->regions = array(
+      'header',
+      'sidebar_first',
+      'content',
+      'sidebar_second',
+      'footer',
+    );
+    $block_storage = $this->container->get('entity_type.manager')->getStorage('block');
+    $blocks = $block_storage->loadByProperties(array('theme' => $this->config('system.theme')->get('default')));
+    foreach ($blocks as $block) {
+      $block->delete();
+    }
+  }
+
+}

web/core/modules/block/src/Tests/BlockUiTest.php

@@ -0,0 +1,312 @@
+<?php
+
+namespace Drupal\block\Tests;
+
+use Drupal\Component\Utility\Html;
+use Drupal\simpletest\WebTestBase;
+
+/**
+ * Tests that the block configuration UI exists and stores data correctly.
+ *
+ * @group block
+ */
+class BlockUiTest extends WebTestBase {
+
+  /**
+   * Modules to install.
+   *
+   * @var array
+   */
+  public static $modules = array('block', 'block_test', 'help', 'condition_test');
+
+  protected $regions;
+
+  /**
+   * The submitted block values used by this test.
+   *
+   * @var array
+   */
+  protected $blockValues;
+
+  /**
+   * The block entities used by this test.
+   *
+   * @var \Drupal\block\BlockInterface[]
+   */
+  protected $blocks;
+
+  /**
+   * An administrative user to configure the test environment.
+   */
+  protected $adminUser;
+
+  protected function setUp() {
+    parent::setUp();
+    // Create and log in an administrative user.
+    $this->adminUser = $this->drupalCreateUser(array(
+      'administer blocks',
+      'access administration pages',
+    ));
+    $this->drupalLogin($this->adminUser);
+
+    // Enable some test blocks.
+    $this->blockValues = array(
+      array(
+        'label' => 'Tools',
+        'tr' => '5',
+        'plugin_id' => 'system_menu_block:tools',
+        'settings' => array('region' => 'sidebar_second', 'id' => 'tools'),
+        'test_weight' => '-1',
+      ),
+      array(
+        'label' => 'Powered by Drupal',
+        'tr' => '16',
+        'plugin_id' => 'system_powered_by_block',
+        'settings' => array('region' => 'footer', 'id' => 'powered'),
+        'test_weight' => '0',
+      ),
+    );
+    $this->blocks = array();
+    foreach ($this->blockValues as $values) {
+      $this->blocks[] = $this->drupalPlaceBlock($values['plugin_id'], $values['settings']);
+    }
+  }
+
+  /**
+   * Test block demo page exists and functions correctly.
+   */
+  public function testBlockDemoUiPage() {
+    $this->drupalPlaceBlock('help_block', array('region' => 'help'));
+    $this->drupalGet('admin/structure/block');
+    $this->clickLink(t('Demonstrate block regions (@theme)', array('@theme' => 'Classy')));
+    $elements = $this->xpath('//div[contains(@class, "region-highlighted")]/div[contains(@class, "block-region") and contains(text(), :title)]', array(':title' => 'Highlighted'));
+    $this->assertTrue(!empty($elements), 'Block demo regions are shown.');
+
+    \Drupal::service('theme_handler')->install(array('test_theme'));
+    $this->drupalGet('admin/structure/block/demo/test_theme');
+    $this->assertEscaped('<strong>Test theme</strong>');
+
+    \Drupal::service('theme_handler')->install(['stable']);
+    $this->drupalGet('admin/structure/block/demo/stable');
+    $this->assertResponse(404, 'Hidden themes that are not the default theme are not supported by the block demo screen');
+  }
+
+  /**
+   * Test block admin page exists and functions correctly.
+   */
+  function testBlockAdminUiPage() {
+    // Visit the blocks admin ui.
+    $this->drupalGet('admin/structure/block');
+    // Look for the blocks table.
+    $blocks_table = $this->xpath("//table[@id='blocks']");
+    $this->assertTrue(!empty($blocks_table), 'The blocks table is being rendered.');
+    // Look for test blocks in the table.
+    foreach ($this->blockValues as $delta => $values) {
+      $block = $this->blocks[$delta];
+      $label = $block->label();
+      $element = $this->xpath('//*[@id="blocks"]/tbody/tr[' . $values['tr'] . ']/td[1]/text()');
+      $this->assertTrue((string) $element[0] == $label, 'The "' . $label . '" block title is set inside the ' . $values['settings']['region'] . ' region.');
+      // Look for a test block region select form element.
+      $this->assertField('blocks[' . $values['settings']['id'] . '][region]', 'The block "' . $values['label'] . '" has a region assignment field.');
+      // Move the test block to the header region.
+      $edit['blocks[' . $values['settings']['id'] . '][region]'] = 'header';
+      // Look for a test block weight select form element.
+      $this->assertField('blocks[' . $values['settings']['id'] . '][weight]', 'The block "' . $values['label'] . '" has a weight assignment field.');
+      // Change the test block's weight.
+      $edit['blocks[' . $values['settings']['id'] . '][weight]'] = $values['test_weight'];
+    }
+    $this->drupalPostForm('admin/structure/block', $edit, t('Save blocks'));
+    foreach ($this->blockValues as $values) {
+      // Check if the region and weight settings changes have persisted.
+      $this->assertOptionSelected(
+        'edit-blocks-' . $values['settings']['id'] . '-region',
+        'header',
+        'The block "' . $label . '" has the correct region assignment (header).'
+      );
+      $this->assertOptionSelected(
+        'edit-blocks-' . $values['settings']['id'] . '-weight',
+        $values['test_weight'],
+        'The block "' . $label . '" has the correct weight assignment (' . $values['test_weight'] . ').'
+      );
+    }
+
+    // Add a block with a machine name the same as a region name.
+    $this->drupalPlaceBlock('system_powered_by_block', ['region' => 'header', 'id' => 'header']);
+    $this->drupalGet('admin/structure/block');
+    $element = $this->xpath('//tr[contains(@class, :class)]', [':class' => 'region-title-header']);
+    $this->assertTrue(!empty($element));
+
+    // Ensure hidden themes do not appear in the UI. Enable another non base
+    // theme and place the local tasks block.
+    $this->assertTrue(\Drupal::service('theme_handler')->themeExists('classy'), 'The classy base theme is enabled');
+    $this->drupalPlaceBlock('local_tasks_block', ['region' => 'header']);
+    \Drupal::service('theme_installer')->install(['stable', 'stark']);
+    $this->drupalGet('admin/structure/block');
+    $theme_handler = \Drupal::service('theme_handler');
+    $this->assertLink($theme_handler->getName('classy'));
+    $this->assertLink($theme_handler->getName('stark'));
+    $this->assertNoLink($theme_handler->getName('stable'));
+
+    $this->drupalGet('admin/structure/block/list/stable');
+    $this->assertResponse(404, 'Placing blocks through UI is not possible for a hidden base theme.');
+
+    \Drupal::configFactory()->getEditable('system.theme')->set('admin', 'stable')->save();
+    \Drupal::service('router.builder')->rebuildIfNeeded();
+    $this->drupalPlaceBlock('local_tasks_block', ['region' => 'header', 'theme' => 'stable']);
+    $this->drupalGet('admin/structure/block');
+    $this->assertLink($theme_handler->getName('stable'));
+    $this->drupalGet('admin/structure/block/list/stable');
+    $this->assertResponse(200, 'Placing blocks through UI is possible for a hidden base theme that is the admin theme.');
+  }
+
+  /**
+   * Tests the block categories on the listing page.
+   */
+  public function testCandidateBlockList() {
+    $arguments = array(
+      ':title' => 'Display message',
+      ':category' => 'Block test',
+      ':href' => 'admin/structure/block/add/test_block_instantiation/classy',
+    );
+    $pattern = '//tr[.//td/div[text()=:title] and .//td[text()=:category] and .//td//a[contains(@href, :href)]]';
+
+    $this->drupalGet('admin/structure/block');
+    $this->clickLinkPartialName('Place block');
+    $elements = $this->xpath($pattern, $arguments);
+    $this->assertTrue(!empty($elements), 'The test block appears in the category for its module.');
+
+    // Trigger the custom category addition in block_test_block_alter().
+    $this->container->get('state')->set('block_test_info_alter', TRUE);
+    $this->container->get('plugin.manager.block')->clearCachedDefinitions();
+
+    $this->drupalGet('admin/structure/block');
+    $this->clickLinkPartialName('Place block');
+    $arguments[':category'] = 'Custom category';
+    $elements = $this->xpath($pattern, $arguments);
+    $this->assertTrue(!empty($elements), 'The test block appears in a custom category controlled by block_test_block_alter().');
+  }
+
+  /**
+   * Tests the behavior of unsatisfied context-aware blocks.
+   */
+  public function testContextAwareUnsatisfiedBlocks() {
+    $arguments = array(
+      ':category' => 'Block test',
+      ':href' => 'admin/structure/block/add/test_context_aware_unsatisfied/classy',
+      ':text' => 'Test context-aware unsatisfied block',
+    );
+
+    $this->drupalGet('admin/structure/block');
+    $this->clickLinkPartialName('Place block');
+    $elements = $this->xpath('//tr[.//td/div[text()=:text] and .//td[text()=:category] and .//td//a[contains(@href, :href)]]', $arguments);
+    $this->assertTrue(empty($elements), 'The context-aware test block does not appear.');
+
+    $definition = \Drupal::service('plugin.manager.block')->getDefinition('test_context_aware_unsatisfied');
+    $this->assertTrue(!empty($definition), 'The context-aware test block does not exist.');
+  }
+
+  /**
+   * Tests the behavior of context-aware blocks.
+   */
+  public function testContextAwareBlocks() {
+    $expected_text = '<div id="test_context_aware--username">' . \Drupal::currentUser()->getUsername() . '</div>';
+    $this->drupalGet('');
+    $this->assertNoText('Test context-aware block');
+    $this->assertNoRaw($expected_text);
+
+    $block_url = 'admin/structure/block/add/test_context_aware/classy';
+    $arguments = array(
+      ':title' => 'Test context-aware block',
+      ':category' => 'Block test',
+      ':href' => $block_url,
+    );
+    $pattern = '//tr[.//td/div[text()=:title] and .//td[text()=:category] and .//td//a[contains(@href, :href)]]';
+
+    $this->drupalGet('admin/structure/block');
+    $this->clickLinkPartialName('Place block');
+    $elements = $this->xpath($pattern, $arguments);
+    $this->assertTrue(!empty($elements), 'The context-aware test block appears.');
+    $definition = \Drupal::service('plugin.manager.block')->getDefinition('test_context_aware');
+    $this->assertTrue(!empty($definition), 'The context-aware test block exists.');
+    $edit = [
+      'region' => 'content',
+      'settings[context_mapping][user]' => '@block_test.multiple_static_context:user2',
+    ];
+    $this->drupalPostForm($block_url, $edit, 'Save block');
+
+    $this->drupalGet('');
+    $this->assertText('Test context-aware block');
+    $this->assertText('User context found.');
+    $this->assertRaw($expected_text);
+
+    // Test context mapping allows empty selection for optional contexts.
+    $this->drupalGet('admin/structure/block/manage/testcontextawareblock');
+    $edit = [
+      'settings[context_mapping][user]' => '',
+    ];
+    $this->drupalPostForm(NULL, $edit, 'Save block');
+    $this->drupalGet('');
+    $this->assertText('No context mapping selected.');
+    $this->assertNoText('User context found.');
+
+    // Tests that conditions with missing context are not displayed.
+    $this->drupalGet('admin/structure/block/manage/testcontextawareblock');
+    $this->assertNoRaw('No existing type');
+    $this->assertNoFieldByXPath('//*[@name="visibility[condition_test_no_existing_type][negate]"]');
+  }
+
+  /**
+   * Tests that the BlockForm populates machine name correctly.
+   */
+  public function testMachineNameSuggestion() {
+    $url = 'admin/structure/block/add/test_block_instantiation/classy';
+    $this->drupalGet($url);
+    $this->assertFieldByName('id', 'displaymessage', 'Block form uses raw machine name suggestion when no instance already exists.');
+    $this->drupalPostForm($url, array(), 'Save block');
+
+    // Now, check to make sure the form starts by autoincrementing correctly.
+    $this->drupalGet($url);
+    $this->assertFieldByName('id', 'displaymessage_2', 'Block form appends _2 to plugin-suggested machine name when an instance already exists.');
+    $this->drupalPostForm($url, array(), 'Save block');
+
+    // And verify that it continues working beyond just the first two.
+    $this->drupalGet($url);
+    $this->assertFieldByName('id', 'displaymessage_3', 'Block form appends _3 to plugin-suggested machine name when two instances already exist.');
+  }
+
+  /**
+   * Tests the block placement indicator.
+   */
+  public function testBlockPlacementIndicator() {
+    // Select the 'Powered by Drupal' block to be placed.
+    $block = array();
+    $block['id'] = strtolower($this->randomMachineName());
+    $block['theme'] = 'classy';
+    $block['region'] = 'content';
+
+    // After adding a block, it will indicate which block was just added.
+    $this->drupalPostForm('admin/structure/block/add/system_powered_by_block', $block, t('Save block'));
+    $this->assertUrl('admin/structure/block/list/classy?block-placement=' . Html::getClass($block['id']));
+
+    // Resaving the block page will remove the block indicator.
+    $this->drupalPostForm(NULL, array(), t('Save blocks'));
+    $this->assertUrl('admin/structure/block/list/classy');
+  }
+
+  /**
+   * Tests if validation errors are passed plugin form to the parent form.
+   */
+  public function testBlockValidateErrors() {
+    $this->drupalPostForm('admin/structure/block/add/test_settings_validation/classy', ['settings[digits]' => 'abc'], t('Save block'));
+
+    $arguments = [':message' => 'Only digits are allowed'];
+    $pattern = '//div[contains(@class,"messages messages--error")]/div[contains(text()[2],:message)]';
+    $elements = $this->xpath($pattern, $arguments);
+    $this->assertTrue($elements, 'Plugin error message found in parent form.');
+
+    $error_class_pattern = '//div[contains(@class,"form-item-settings-digits")]/input[contains(@class,"error")]';
+    $error_class = $this->xpath($error_class_pattern);
+    $this->assertTrue($error_class, 'Plugin error class found in parent form.');
+  }
+
+}

web/core/modules/block/src/Tests/BlockXssTest.php

@@ -0,0 +1,167 @@
+<?php
+
+namespace Drupal\block\Tests;
+
+use Drupal\block_content\Entity\BlockContent;
+use Drupal\block_content\Entity\BlockContentType;
+use Drupal\Core\Url;
+use Drupal\simpletest\WebTestBase;
+use Drupal\system\Entity\Menu;
+use Drupal\views\Entity\View;
+
+/**
+ * Tests that the block module properly escapes block descriptions.
+ *
+ * @group block
+ */
+class BlockXssTest extends WebTestBase {
+
+  /**
+   * Modules to install.
+   *
+   * @var array
+   */
+  public static $modules = ['block', 'block_content', 'menu_ui', 'views'];
+
+  /**
+   * Tests that nothing is escaped other than the blocks explicitly tested.
+   */
+  public function testNoUnexpectedEscaping() {
+    $this->drupalLogin($this->drupalCreateUser(['administer blocks', 'access administration pages']));
+    $this->drupalGet(Url::fromRoute('block.admin_display'));
+    $this->clickLinkPartialName('Place block');
+    $this->assertNoEscaped('<');
+  }
+
+  /**
+   * Tests XSS in title.
+   */
+  public function testXssInTitle() {
+    $this->container->get('module_installer')->install(['block_test']);
+    $this->drupalPlaceBlock('test_xss_title', ['label' => '<script>alert("XSS label");</script>']);
+
+    \Drupal::state()->set('block_test.content', $this->randomMachineName());
+    $this->drupalGet('');
+    $this->assertNoRaw('<script>alert("XSS label");</script>', 'The block title was properly sanitized when rendered.');
+
+    $this->drupalLogin($this->drupalCreateUser(['administer blocks', 'access administration pages']));
+    $default_theme = $this->config('system.theme')->get('default');
+    $this->drupalGet('admin/structure/block/list/' . $default_theme);
+    $this->assertNoRaw("<script>alert('XSS subject');</script>", 'The block title was properly sanitized in Block Plugin UI Admin page.');
+  }
+
+  /**
+   * Tests XSS in category.
+   */
+  public function testXssInCategory() {
+    $this->container->get('module_installer')->install(['block_test']);
+    $this->drupalPlaceBlock('test_xss_title');
+    $this->drupalLogin($this->drupalCreateUser(['administer blocks', 'access administration pages']));
+    $this->drupalGet(Url::fromRoute('block.admin_display'));
+    $this->clickLinkPartialName('Place block');
+    $this->assertNoRaw("<script>alert('XSS category');</script>");
+  }
+
+  /**
+   * Tests various modules that provide blocks for XSS.
+   */
+  public function testBlockXss() {
+    $this->drupalLogin($this->rootUser);
+
+    $this->doViewTest();
+    $this->doMenuTest();
+    $this->doBlockContentTest();
+
+    $this->drupalGet(Url::fromRoute('block.admin_display'));
+    $this->clickLinkPartialName('Place block');
+    $this->assertNoRaw('&amp;lt;', 'The page does not have double escaped HTML tags.');
+  }
+
+  /**
+   * Tests XSS coming from View block labels.
+   */
+  protected function doViewTest() {
+    // Create a View without a custom label for its block Display. The
+    // admin_label of the block then becomes just the View's label.
+    $view = View::create([
+      'id' => $this->randomMachineName(),
+      'label' => '<script>alert("view1");</script>',
+    ]);
+    $view->addDisplay('block');
+    $view->save();
+
+    // Create a View with a custom label for its block Display. The
+    // admin_label of the block then becomes the View's label combined with
+    // the Display's label.
+    $view = View::create([
+      'id' => $this->randomMachineName(),
+      'label' => '<script>alert("view2");</script>',
+    ]);
+    $view->addDisplay('block', 'Fish & chips');
+    $view->save();
+
+    $this->drupalGet(Url::fromRoute('block.admin_display'));
+    $this->clickLinkPartialName('Place block');
+
+    // \Drupal\views\Plugin\Derivative\ViewsBlock::getDerivativeDefinitions()
+    // has a different code path for an admin label based only on the View
+    // label versus one based on both the View label and the Display label.
+    // Ensure that this test is covering both code paths by asserting the
+    // absence of a ":" for the first View and the presence of a ":" for the
+    // second one. Note that the second assertion is redundant with the one
+    // further down which also checks for the Display label, but is included
+    // here for clarity.
+    $this->assertNoEscaped('<script>alert("view1");</script>:');
+    $this->assertEscaped('<script>alert("view2");</script>:');
+
+    // Assert that the blocks have their admin labels escaped and
+    // don't appear anywhere unescaped.
+    $this->assertEscaped('<script>alert("view1");</script>');
+    $this->assertNoRaw('<script>alert("view1");</script>');
+    $this->assertEscaped('<script>alert("view2");</script>: Fish & chips');
+    $this->assertNoRaw('<script>alert("view2");</script>');
+    $this->assertNoRaw('Fish & chips');
+
+    // Assert the Display label doesn't appear anywhere double escaped.
+    $this->assertNoRaw('Fish & chips');
+    $this->assertNoRaw('Fish &amp;amp; chips');
+  }
+
+  /**
+   * Tests XSS coming from Menu block labels.
+   */
+  protected function doMenuTest() {
+    Menu::create([
+      'id' => $this->randomMachineName(),
+      'label' => '<script>alert("menu");</script>',
+    ])->save();
+
+    $this->drupalGet(Url::fromRoute('block.admin_display'));
+    $this->clickLinkPartialName('Place block');
+
+    $this->assertEscaped('<script>alert("menu");</script>');
+    $this->assertNoRaw('<script>alert("menu");</script>');
+  }
+
+  /**
+   * Tests XSS coming from Block Content block info.
+   */
+  protected function doBlockContentTest() {
+    BlockContentType::create([
+      'id' => 'basic',
+      'label' => 'basic',
+      'revision' => TRUE,
+    ])->save();
+    BlockContent::create([
+      'type' => 'basic',
+      'info' => '<script>alert("block_content");</script>',
+    ])->save();
+
+    $this->drupalGet(Url::fromRoute('block.admin_display'));
+    $this->clickLinkPartialName('Place block');
+
+    $this->assertEscaped('<script>alert("block_content");</script>');
+    $this->assertNoRaw('<script>alert("block_content");</script>');
+  }
+
+}

web/core/modules/block/src/Tests/NewDefaultThemeBlocksTest.php

@@ -0,0 +1,73 @@
+<?php
+
+namespace Drupal\block\Tests;
+
+use Drupal\simpletest\WebTestBase;
+
+/**
+ * Tests that the new default theme gets blocks.
+ *
+ * @group block
+ */
+class NewDefaultThemeBlocksTest extends WebTestBase {
+
+  /**
+   * Modules to install.
+   *
+   * @var array
+   */
+  public static $modules = array('block');
+
+  /**
+   * Check the enabled Bartik blocks are correctly copied over.
+   */
+  function testNewDefaultThemeBlocks() {
+    $default_theme = $this->config('system.theme')->get('default');
+
+    // Add two instances of the user login block.
+    $this->drupalPlaceBlock('user_login_block', array(
+      'id' => $default_theme . '_' . strtolower($this->randomMachineName(8)),
+    ));
+    $this->drupalPlaceBlock('user_login_block', array(
+      'id' => $default_theme . '_' . strtolower($this->randomMachineName(8)),
+    ));
+
+    // Add an instance of a different block.
+    $this->drupalPlaceBlock('system_powered_by_block', array(
+      'id' => $default_theme . '_' . strtolower($this->randomMachineName(8)),
+    ));
+
+    // Install a different theme.
+    $new_theme = 'bartik';
+    $this->assertFalse($new_theme == $default_theme, 'The new theme is different from the previous default theme.');
+    \Drupal::service('theme_handler')->install(array($new_theme));
+    $this->config('system.theme')
+      ->set('default', $new_theme)
+      ->save();
+
+    // Ensure that the new theme has all the blocks as the previous default.
+    $default_block_names = $this->container->get('entity.query')->get('block')
+      ->condition('theme', $default_theme)
+      ->execute();
+    $new_blocks = $this->container->get('entity.query')->get('block')
+      ->condition('theme', $new_theme)
+      ->execute();
+    $this->assertTrue(count($default_block_names) == count($new_blocks), 'The new default theme has the same number of blocks as the previous theme.');
+    foreach ($default_block_names as $default_block_name) {
+      // Remove the matching block from the list of blocks in the new theme.
+      // E.g., if the old theme has block.block.stark_admin,
+      // unset block.block.bartik_admin.
+      unset($new_blocks[str_replace($default_theme . '_', $new_theme . '_', $default_block_name)]);
+    }
+    $this->assertTrue(empty($new_blocks), 'The new theme has exactly the same blocks as the previous default theme.');
+
+    // Install a hidden base theme and ensure blocks are not copied.
+    $base_theme = 'test_basetheme';
+    \Drupal::service('theme_handler')->install([$base_theme]);
+    $new_blocks = $this->container->get('entity.query')->get('block')
+      ->condition('theme', $base_theme)
+      ->execute();
+    $this->assertTrue(empty($new_blocks), 'Installing a hidden base theme does not copy blocks from the default theme.');
+  }
+
+}

web/core/modules/block/src/Tests/NonDefaultBlockAdminTest.php

@@ -0,0 +1,42 @@
+<?php
+
+namespace Drupal\block\Tests;
+
+use Drupal\simpletest\WebTestBase;
+
+/**
+ * Tests the block administration page for a non-default theme.
+ *
+ * @group block
+ */
+class NonDefaultBlockAdminTest extends WebTestBase {
+
+  /**
+   * Modules to install.
+   *
+   * @var array
+   */
+  public static $modules = array('block');
+
+  /**
+   * {@inheritdoc}
+   */
+  protected function setUp() {
+    parent::setUp();
+
+    $this->drupalPlaceBlock('local_tasks_block');
+  }
+
+  /**
+   * Test non-default theme admin.
+   */
+  function testNonDefaultBlockAdmin() {
+    $admin_user = $this->drupalCreateUser(array('administer blocks', 'administer themes'));
+    $this->drupalLogin($admin_user);
+    $new_theme = 'bartik';
+    \Drupal::service('theme_handler')->install(array($new_theme));
+    $this->drupalGet('admin/structure/block/list/' . $new_theme);
+    $this->assertText('Bartik(' . t('active tab') . ')', 'Tab for non-default theme found.');
+  }
+
+}

web/core/modules/block/src/Tests/Update/BlockConditionMissingSchemaUpdateTest.php

@@ -0,0 +1,53 @@
+<?php
+
+namespace Drupal\block\Tests\Update;
+
+use Drupal\system\Tests\Update\UpdatePathTestBase;
+
+/**
+ * Tests the upgrade path for block with conditions missing context.
+ *
+ * @see https://www.drupal.org/node/2811519
+ *
+ * @group Update
+ */
+class BlockConditionMissingSchemaUpdateTest extends UpdatePathTestBase {
+
+  /**
+   * This test does not have a failed update but the configuration has missing
+   * schema so can not do the full post update testing offered by
+   * UpdatePathTestBase.
+   *
+   * @var bool
+   *
+   * @see \Drupal\system\Tests\Update\UpdatePathTestBase::runUpdates()
+   */
+  protected $checkFailedUpdates = FALSE;
+
+  /**
+   * {@inheritdoc}
+   */
+  protected static $modules = ['block_test', 'language'];
+
+  /**
+   * {@inheritdoc}
+   */
+  protected function setDatabaseDumpFiles() {
+    $this->databaseDumpFiles = [
+      __DIR__ . '/../../../../system/tests/fixtures/update/drupal-8.bare.standard.php.gz',
+      __DIR__ . '/../../../tests/fixtures/update/drupal-8.block-test-enabled-missing-schema.php',
+    ];
+  }
+
+  /**
+   * Tests that block context mapping is updated properly.
+   */
+  public function testUpdateHookN() {
+    $this->runUpdates();
+    $this->drupalGet('<front>');
+    // If the block is fixed by block_post_update_fix_negate_in_conditions()
+    // then it will be visible.
+    $this->assertText('Test missing schema on conditions');
+  }
+
+}

web/core/modules/block/src/Tests/Update/BlockContextMappingUpdateFilledTest.php

@@ -0,0 +1,20 @@
+<?php
+
+namespace Drupal\block\Tests\Update;
+
+/**
+ * Runs BlockContextMappingUpdateTest with a dump filled with content.
+ *
+ * @group Update
+ */
+class BlockContextMappingUpdateFilledTest extends BlockContextMappingUpdateTest {
+
+  /**
+   * {@inheritdoc}
+   */
+  protected function setDatabaseDumpFiles() {
+    parent::setDatabaseDumpFiles();
+    $this->databaseDumpFiles[0] = __DIR__ . '/../../../../system/tests/fixtures/update/drupal-8.filled.standard.php.gz';
+  }
+
+}

web/core/modules/block/src/Tests/Update/BlockContextMappingUpdateTest.php

@@ -0,0 +1,106 @@
+<?php
+
+namespace Drupal\block\Tests\Update;
+
+use Drupal\block\Entity\Block;
+use Drupal\node\Entity\Node;
+use Drupal\system\Tests\Update\UpdatePathTestBase;
+
+/**
+ * Tests the upgrade path for block context mapping renames.
+ *
+ * @see https://www.drupal.org/node/2354889
+ *
+ * @group Update
+ */
+class BlockContextMappingUpdateTest extends UpdatePathTestBase {
+
+  /**
+   * {@inheritdoc}
+   */
+  protected static $modules = ['block_test', 'language'];
+
+  /**
+   * {@inheritdoc}
+   */
+  protected function setDatabaseDumpFiles() {
+    $this->databaseDumpFiles = [
+      __DIR__ . '/../../../../system/tests/fixtures/update/drupal-8.bare.standard.php.gz',
+      __DIR__ . '/../../../../system/tests/fixtures/update/drupal-8.block-context-manager-2354889.php',
+      __DIR__ . '/../../../../system/tests/fixtures/update/drupal-8.language-enabled.php',
+      __DIR__ . '/../../../../system/tests/fixtures/update/drupal-8.block-test-enabled.php',
+    ];
+  }
+
+  /**
+   * Tests that block context mapping is updated properly.
+   */
+  public function testUpdateHookN() {
+    $this->runUpdates();
+    $this->assertRaw('Encountered an unknown context mapping key coming probably from a contributed or custom module: One or more mappings could not be updated. Please manually review your visibility settings for the following blocks, which are disabled now:<ul><li>User login (Visibility: Baloney spam)</li></ul>');
+
+    // Disable maintenance mode.
+    \Drupal::state()->set('system.maintenance_mode', FALSE);
+
+    // We finished updating so we can log in the user now.
+    $this->drupalLogin($this->rootUser);
+
+    // The block that we are testing has the following visibility rules:
+    // - only visible on node pages
+    // - only visible to authenticated users.
+    $block_title = 'Test for 2354889';
+
+    // Create two nodes, a page and an article.
+    $page = Node::create([
+      'type' => 'page',
+      'title' => 'Page node',
+    ]);
+    $page->save();
+
+    $article = Node::create([
+      'type' => 'article',
+      'title' => 'Article node',
+    ]);
+    $article->save();
+
+    // Check that the block appears only on Page nodes for authenticated users.
+    $this->drupalGet('node/' . $page->id());
+    $this->assertRaw($block_title, 'Test block is visible on a Page node as an authenticated user.');
+
+    $this->drupalGet('node/' . $article->id());
+    $this->assertNoRaw($block_title, 'Test block is not visible on a Article node as an authenticated user.');
+
+    $this->drupalLogout();
+
+    // Check that the block does not appear on any page for anonymous users.
+    $this->drupalGet('node/' . $page->id());
+    $this->assertNoRaw($block_title, 'Test block is not visible on a Page node as an anonymous user.');
+
+    $this->drupalGet('node/' . $article->id());
+    $this->assertNoRaw($block_title, 'Test block is not visible on a Article node as an anonymous user.');
+
+    // Ensure that all the context mappings got updated properly.
+    $block = Block::load('testfor2354889');
+    $visibility = $block->get('visibility');
+    $this->assertEqual('@node.node_route_context:node', $visibility['node_type']['context_mapping']['node']);
+    $this->assertEqual('@user.current_user_context:current_user', $visibility['user_role']['context_mapping']['user']);
+    $this->assertEqual('@language.current_language_context:language_interface', $visibility['language']['context_mapping']['language']);
+
+    // Check that a block with invalid context is being disabled and that it can
+    // still be edited afterward.
+    $disabled_block = Block::load('thirdtestfor2354889');
+    $this->assertFalse($disabled_block->status(), 'Block with invalid context is disabled');
+
+    $this->assertEqual(['thirdtestfor2354889' => ['missing_context_ids' => ['baloney_spam' => ['node_type']], 'status' => TRUE]], \Drupal::keyValue('update_backup')->get('block_update_8001'));
+
+    $disabled_block_visibility = $disabled_block->get('visibility');
+    $this->assertTrue(!isset($disabled_block_visibility['node_type']), 'The problematic visibility condition has been removed.');
+
+    $admin_user = $this->drupalCreateUser(['administer blocks']);
+    $this->drupalLogin($admin_user);
+
+    $this->drupalGet('admin/structure/block/manage/thirdtestfor2354889');
+    $this->assertResponse('200');
+  }
+
+}

web/core/modules/block/src/Tests/Views/DisplayBlockTest.php

@@ -0,0 +1,371 @@
+<?php
+
+namespace Drupal\block\Tests\Views;
+
+use Drupal\Component\Serialization\Json;
+use Drupal\Core\Url;
+use Drupal\system\Tests\Cache\AssertPageCacheContextsAndTagsTrait;
+use Drupal\views\Entity\View;
+use Drupal\views\Views;
+use Drupal\views\Tests\ViewTestBase;
+use Drupal\views\Tests\ViewTestData;
+use Drupal\Core\Template\Attribute;
+
+/**
+ * Tests the block display plugin.
+ *
+ * @group block
+ * @see \Drupal\block\Plugin\views\display\Block
+ */
+class DisplayBlockTest extends ViewTestBase {
+
+  use AssertPageCacheContextsAndTagsTrait;
+
+  /**
+   * Modules to install.
+   *
+   * @var array
+   */
+  public static $modules = array('node', 'block_test_views', 'test_page_test', 'contextual', 'views_ui');
+
+  /**
+   * Views used by this test.
+   *
+   * @var array
+   */
+  public static $testViews = array('test_view_block', 'test_view_block2');
+
+  protected function setUp() {
+    parent::setUp();
+
+    ViewTestData::createTestViews(get_class($this), array('block_test_views'));
+    $this->enableViewsTestModule();
+  }
+
+  /**
+   * Tests default and custom block categories.
+   */
+  public function testBlockCategory() {
+    $this->drupalLogin($this->drupalCreateUser(array('administer views', 'administer blocks')));
+
+    // Create a new view in the UI.
+    $edit = array();
+    $edit['label'] = $this->randomString();
+    $edit['id'] = strtolower($this->randomMachineName());
+    $edit['show[wizard_key]'] = 'standard:views_test_data';
+    $edit['description'] = $this->randomString();
+    $edit['block[create]'] = TRUE;
+    $edit['block[style][row_plugin]'] = 'fields';
+    $this->drupalPostForm('admin/structure/views/add', $edit, t('Save and edit'));
+
+    $pattern = '//tr[.//td[text()=:category] and .//td//a[contains(@href, :href)]]';
+
+    // Test that the block was given a default category corresponding to its
+    // base table.
+    $arguments = array(
+      ':href' => \Drupal::Url('block.admin_add', array(
+        'plugin_id' => 'views_block:' . $edit['id'] . '-block_1',
+        'theme' => 'classy',
+      )),
+      ':category' => t('Lists (Views)'),
+    );
+    $this->drupalGet('admin/structure/block');
+    $this->clickLinkPartialName('Place block');
+    $elements = $this->xpath($pattern, $arguments);
+    $this->assertTrue(!empty($elements), 'The test block appears in the category for its base table.');
+
+    // Duplicate the block before changing the category.
+    $this->drupalPostForm('admin/structure/views/view/' . $edit['id'] . '/edit/block_1', array(), t('Duplicate @display_title', array('@display_title' => 'Block')));
+    $this->assertUrl('admin/structure/views/view/' . $edit['id'] . '/edit/block_2');
+
+    // Change the block category to a random string.
+    $this->drupalGet('admin/structure/views/view/' . $edit['id'] . '/edit/block_1');
+    $link = $this->xpath('//a[@id="views-block-1-block-category" and normalize-space(text())=:category]', $arguments);
+    $this->assertTrue(!empty($link));
+    $this->clickLink(t('Lists (Views)'));
+    $category = $this->randomString();
+    $this->drupalPostForm(NULL, array('block_category' => $category), t('Apply'));
+
+    // Duplicate the block after changing the category.
+    $this->drupalPostForm(NULL, array(), t('Duplicate @display_title', array('@display_title' => 'Block')));
+    $this->assertUrl('admin/structure/views/view/' . $edit['id'] . '/edit/block_3');
+
+    $this->drupalPostForm(NULL, array(), t('Save'));
+
+    // Test that the blocks are listed under the correct categories.
+    $arguments[':category'] = $category;
+    $this->drupalGet('admin/structure/block');
+    $this->clickLinkPartialName('Place block');
+    $elements = $this->xpath($pattern, $arguments);
+    $this->assertTrue(!empty($elements), 'The test block appears in the custom category.');
+
+    $arguments = array(
+      ':href' => \Drupal::Url('block.admin_add', array(
+        'plugin_id' => 'views_block:' . $edit['id'] . '-block_2',
+        'theme' => 'classy',
+      )),
+      ':category' => t('Lists (Views)'),
+    );
+    $elements = $this->xpath($pattern, $arguments);
+    $this->assertTrue(!empty($elements), 'The first duplicated test block remains in the original category.');
+
+    $arguments = array(
+      ':href' => \Drupal::Url('block.admin_add', array(
+        'plugin_id' => 'views_block:' . $edit['id'] . '-block_3',
+        'theme' => 'classy',
+      )),
+      ':category' => $category,
+    );
+    $elements = $this->xpath($pattern, $arguments);
+    $this->assertTrue(!empty($elements), 'The second duplicated test block appears in the custom category.');
+  }
+
+  /**
+   * Tests removing a block display.
+   */
+  public function testDeleteBlockDisplay() {
+    // To test all combinations possible we first place create two instances
+    // of the block display of the first view.
+    $block_1 = $this->drupalPlaceBlock('views_block:test_view_block-block_1', array('label' => 'test_view_block-block_1:1'));
+    $block_2 = $this->drupalPlaceBlock('views_block:test_view_block-block_1', array('label' => 'test_view_block-block_1:2'));
+
+    // Then we add one instance of blocks for each of the two displays of the
+    // second view.
+    $block_3 = $this->drupalPlaceBlock('views_block:test_view_block2-block_1', array('label' => 'test_view_block2-block_1'));
+    $block_4 = $this->drupalPlaceBlock('views_block:test_view_block2-block_2', array('label' => 'test_view_block2-block_2'));
+
+    $this->drupalGet('test-page');
+    $this->assertBlockAppears($block_1);
+    $this->assertBlockAppears($block_2);
+    $this->assertBlockAppears($block_3);
+    $this->assertBlockAppears($block_4);
+
+    $block_storage = $this->container->get('entity_type.manager')->getStorage('block');
+
+    // Remove the block display, so both block entities from the first view
+    // should both disappear.
+    $view = Views::getView('test_view_block');
+    $view->initDisplay();
+    $view->displayHandlers->remove('block_1');
+    $view->storage->save();
+
+    $this->assertFalse($block_storage->load($block_1->id()), 'The block for this display was removed.');
+    $this->assertFalse($block_storage->load($block_2->id()), 'The block for this display was removed.');
+    $this->assertTrue($block_storage->load($block_3->id()), 'A block from another view was unaffected.');
+    $this->assertTrue($block_storage->load($block_4->id()), 'A block from another view was unaffected.');
+    $this->drupalGet('test-page');
+    $this->assertNoBlockAppears($block_1);
+    $this->assertNoBlockAppears($block_2);
+    $this->assertBlockAppears($block_3);
+    $this->assertBlockAppears($block_4);
+
+    // Remove the first block display of the second view and ensure the block
+    // instance of the second block display still exists.
+    $view = Views::getView('test_view_block2');
+    $view->initDisplay();
+    $view->displayHandlers->remove('block_1');
+    $view->storage->save();
+
+    $this->assertFalse($block_storage->load($block_3->id()), 'The block for this display was removed.');
+    $this->assertTrue($block_storage->load($block_4->id()), 'A block from another display on the same view was unaffected.');
+    $this->drupalGet('test-page');
+    $this->assertNoBlockAppears($block_3);
+    $this->assertBlockAppears($block_4);
+  }
+
+  /**
+   * Test the block form for a Views block.
+   */
+  public function testViewsBlockForm() {
+    $this->drupalLogin($this->drupalCreateUser(array('administer blocks')));
+    $default_theme = $this->config('system.theme')->get('default');
+    $this->drupalGet('admin/structure/block/add/views_block:test_view_block-block_1/' . $default_theme);
+    $elements = $this->xpath('//input[@name="label"]');
+    $this->assertTrue(empty($elements), 'The label field is not found for Views blocks.');
+    // Test that that machine name field is hidden from display and has been
+    // saved as expected from the default value.
+    $this->assertNoFieldById('edit-machine-name', 'views_block__test_view_block_1', 'The machine name is hidden on the views block form.');
+    // Save the block.
+    $this->drupalPostForm(NULL, array(), t('Save block'));
+    $storage = $this->container->get('entity_type.manager')->getStorage('block');
+    $block = $storage->load('views_block__test_view_block_block_1');
+    // This will only return a result if our new block has been created with the
+    // expected machine name.
+    $this->assertTrue(!empty($block), 'The expected block was loaded.');
+
+    for ($i = 2; $i <= 3; $i++) {
+      // Place the same block again and make sure we have a new ID.
+      $this->drupalPostForm('admin/structure/block/add/views_block:test_view_block-block_1/' . $default_theme, array(), t('Save block'));
+      $block = $storage->load('views_block__test_view_block_block_1_' . $i);
+      // This will only return a result if our new block has been created with the
+      // expected machine name.
+      $this->assertTrue(!empty($block), 'The expected block was loaded.');
+    }
+
+    // Tests the override capability of items per page.
+    $this->drupalGet('admin/structure/block/add/views_block:test_view_block-block_1/' . $default_theme);
+    $edit = array();
+    $edit['settings[override][items_per_page]'] = 10;
+
+    $this->drupalPostForm('admin/structure/block/add/views_block:test_view_block-block_1/' . $default_theme, $edit, t('Save block'));
+
+    $block = $storage->load('views_block__test_view_block_block_1_4');
+    $config = $block->getPlugin()->getConfiguration();
+    $this->assertEqual(10, $config['items_per_page'], "'Items per page' is properly saved.");
+
+    $edit['settings[override][items_per_page]'] = 5;
+    $this->drupalPostForm('admin/structure/block/manage/views_block__test_view_block_block_1_4', $edit, t('Save block'));
+
+    $block = $storage->load('views_block__test_view_block_block_1_4');
+
+    $config = $block->getPlugin()->getConfiguration();
+    $this->assertEqual(5, $config['items_per_page'], "'Items per page' is properly saved.");
+
+    // Tests the override of the label capability.
+    $edit = array();
+    $edit['settings[views_label_checkbox]'] = 1;
+    $edit['settings[views_label]'] = 'Custom title';
+    $this->drupalPostForm('admin/structure/block/add/views_block:test_view_block-block_1/' . $default_theme, $edit, t('Save block'));
+
+    $block = $storage->load('views_block__test_view_block_block_1_5');
+    $config = $block->getPlugin()->getConfiguration();
+    $this->assertEqual('Custom title', $config['views_label'], "'Label' is properly saved.");
+  }
+
+  /**
+   * Tests the actual rendering of the views block.
+   */
+  public function testBlockRendering() {
+    // Create a block and set a custom title.
+    $block = $this->drupalPlaceBlock('views_block:test_view_block-block_1', array('label' => 'test_view_block-block_1:1', 'views_label' => 'Custom title'));
+    $this->drupalGet('');
+
+    $result = $this->xpath('//div[contains(@class, "region-sidebar-first")]/div[contains(@class, "block-views")]/h2');
+    $this->assertEqual((string) $result[0], 'Custom title');
+
+    // Don't override the title anymore.
+    $plugin = $block->getPlugin();
+    $plugin->setConfigurationValue('views_label', '');
+    $block->save();
+
+    $this->drupalGet('');
+    $result = $this->xpath('//div[contains(@class, "region-sidebar-first")]/div[contains(@class, "block-views")]/h2');
+    $this->assertEqual((string) $result[0], 'test_view_block');
+
+    // Hide the title.
+    $block->getPlugin()->setConfigurationValue('label_display', FALSE);
+    $block->save();
+
+    $this->drupalGet('');
+    $result = $this->xpath('//div[contains(@class, "region-sidebar-first")]/div[contains(@class, "block-views")]/h2');
+    $this->assertTrue(empty($result), 'The title is not visible.');
+
+    $this->assertCacheTags(array_merge($block->getCacheTags(), ['block_view', 'config:block_list', 'config:system.site', 'config:views.view.test_view_block' , 'rendered']));
+  }
+
+  /**
+   * Tests the various testcases of empty block rendering.
+   */
+  public function testBlockEmptyRendering() {
+    $url = new Url('test_page_test.test_page');
+    // Remove all views_test_data entries.
+    \Drupal::database()->truncate('views_test_data')->execute();
+    /** @var \Drupal\views\ViewEntityInterface $view */
+    $view = View::load('test_view_block');
+    $view->invalidateCaches();
+
+    $block = $this->drupalPlaceBlock('views_block:test_view_block-block_1', array('label' => 'test_view_block-block_1:1', 'views_label' => 'Custom title'));
+    $this->drupalGet('');
+    $this->assertEqual(1, count($this->xpath('//div[contains(@class, "block-views-blocktest-view-block-block-1")]')));
+
+    $display = &$view->getDisplay('block_1');
+    $display['display_options']['block_hide_empty'] = TRUE;
+    $view->save();
+
+    $this->drupalGet($url);
+    $this->assertEqual(0, count($this->xpath('//div[contains(@class, "block-views-blocktest-view-block-block-1")]')));
+    // Ensure that the view cachability metadata is propagated even, for an
+    // empty block.
+    $this->assertCacheTags(array_merge($block->getCacheTags(), ['block_view', 'config:block_list', 'config:views.view.test_view_block' , 'rendered']));
+    $this->assertCacheContexts(['url.query_args:_wrapper_format']);
+
+    // Add a header displayed on empty result.
+    $display = &$view->getDisplay('block_1');
+    $display['display_options']['defaults']['header'] = FALSE;
+    $display['display_options']['header']['example'] = [
+      'field' => 'area_text_custom',
+      'id' => 'area_text_custom',
+      'table' => 'views',
+      'plugin_id' => 'text_custom',
+      'content' => 'test header',
+      'empty' => TRUE,
+    ];
+    $view->save();
+
+    $this->drupalGet($url);
+    $this->assertEqual(1, count($this->xpath('//div[contains(@class, "block-views-blocktest-view-block-block-1")]')));
+    $this->assertCacheTags(array_merge($block->getCacheTags(), ['block_view', 'config:block_list', 'config:views.view.test_view_block' , 'rendered']));
+    $this->assertCacheContexts(['url.query_args:_wrapper_format']);
+
+    // Hide the header on empty results.
+    $display = &$view->getDisplay('block_1');
+    $display['display_options']['defaults']['header'] = FALSE;
+    $display['display_options']['header']['example'] = [
+      'field' => 'area_text_custom',
+      'id' => 'area_text_custom',
+      'table' => 'views',
+      'plugin_id' => 'text_custom',
+      'content' => 'test header',
+      'empty' => FALSE,
+    ];
+    $view->save();
+
+    $this->drupalGet($url);
+    $this->assertEqual(0, count($this->xpath('//div[contains(@class, "block-views-blocktest-view-block-block-1")]')));
+    $this->assertCacheTags(array_merge($block->getCacheTags(), ['block_view', 'config:block_list', 'config:views.view.test_view_block' , 'rendered']));
+    $this->assertCacheContexts(['url.query_args:_wrapper_format']);
+
+    // Add an empty text.
+    $display = &$view->getDisplay('block_1');
+    $display['display_options']['defaults']['empty'] = FALSE;
+    $display['display_options']['empty']['example'] = [
+      'field' => 'area_text_custom',
+      'id' => 'area_text_custom',
+      'table' => 'views',
+      'plugin_id' => 'text_custom',
+      'content' => 'test empty',
+    ];
+    $view->save();
+
+    $this->drupalGet($url);
+    $this->assertEqual(1, count($this->xpath('//div[contains(@class, "block-views-blocktest-view-block-block-1")]')));
+    $this->assertCacheTags(array_merge($block->getCacheTags(), ['block_view', 'config:block_list', 'config:views.view.test_view_block' , 'rendered']));
+    $this->assertCacheContexts(['url.query_args:_wrapper_format']);
+  }
+
+  /**
+   * Tests the contextual links on a Views block.
+   */
+  public function testBlockContextualLinks() {
+    $this->drupalLogin($this->drupalCreateUser(array('administer views', 'access contextual links', 'administer blocks')));
+    $block = $this->drupalPlaceBlock('views_block:test_view_block-block_1');
+    $cached_block = $this->drupalPlaceBlock('views_block:test_view_block-block_1');
+    $this->drupalGet('test-page');
+
+    $id = 'block:block=' . $block->id() . ':langcode=en|entity.view.edit_form:view=test_view_block:location=block&name=test_view_block&display_id=block_1&langcode=en';
+    $cached_id = 'block:block=' . $cached_block->id() . ':langcode=en|entity.view.edit_form:view=test_view_block:location=block&name=test_view_block&display_id=block_1&langcode=en';
+    // @see \Drupal\contextual\Tests\ContextualDynamicContextTest:assertContextualLinkPlaceHolder()
+    $this->assertRaw('<div' . new Attribute(array('data-contextual-id' => $id)) . '></div>', format_string('Contextual link placeholder with id @id exists.', array('@id' => $id)));
+    $this->assertRaw('<div' . new Attribute(array('data-contextual-id' => $cached_id)) . '></div>', format_string('Contextual link placeholder with id @id exists.', array('@id' => $cached_id)));
+
+    // Get server-rendered contextual links.
+    // @see \Drupal\contextual\Tests\ContextualDynamicContextTest:renderContextualLinks()
+    $post = array('ids[0]' => $id, 'ids[1]' => $cached_id);
+    $response = $this->drupalPostWithFormat('contextual/render', 'json', $post, array('query' => array('destination' => 'test-page')));
+    $this->assertResponse(200);
+    $json = Json::decode($response);
+    $this->assertIdentical($json[$id], '<ul class="contextual-links"><li class="block-configure"><a href="' . base_path() . 'admin/structure/block/manage/' . $block->id() . '">Configure block</a></li><li class="entityviewedit-form"><a href="' . base_path() . 'admin/structure/views/view/test_view_block/edit/block_1">Edit view</a></li></ul>');
+    $this->assertIdentical($json[$cached_id], '<ul class="contextual-links"><li class="block-configure"><a href="' . base_path() . 'admin/structure/block/manage/' . $cached_block->id() . '">Configure block</a></li><li class="entityviewedit-form"><a href="' . base_path() . 'admin/structure/views/view/test_view_block/edit/block_1">Edit view</a></li></ul>');
+  }
+
+}

web/core/modules/block/src/Theme/AdminDemoNegotiator.php

@@ -0,0 +1,29 @@
+<?php
+
+namespace Drupal\block\Theme;
+
+use Drupal\Core\Routing\RouteMatchInterface;
+use Drupal\Core\Theme\ThemeNegotiatorInterface;
+
+/**
+ * Negotiates the theme for the block admin demo page via the URL.
+ */
+class AdminDemoNegotiator implements ThemeNegotiatorInterface {
+
+  /**
+   * {@inheritdoc}
+   */
+  public function applies(RouteMatchInterface $route_match) {
+    return $route_match->getRouteName() == 'block.admin_demo';
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function determineActiveTheme(RouteMatchInterface $route_match) {
+    // We return exactly what was passed in, to guarantee that the page will
+    // always be displayed using the theme whose blocks are being configured.
+    return $route_match->getParameter('theme');
+  }
+
+}

web/core/modules/block/templates/block.html.twig

@@ -0,0 +1,39 @@
+{#
+/**
+ * @file
+ * Default theme implementation to display a block.
+ *
+ * Available variables:
+ * - plugin_id: The ID of the block implementation.
+ * - label: The configured label of the block if visible.
+ * - configuration: A list of the block's configuration values.
+ *   - label: The configured label for the block.
+ *   - label_display: The display settings for the label.
+ *   - provider: The module or other provider that provided this block plugin.
+ *   - Block plugin specific settings will also be stored here.
+ * - content: The content of this block.
+ * - attributes: array of HTML attributes populated by modules, intended to
+ *   be added to the main container tag of this template.
+ *   - id: A valid HTML ID and guaranteed unique.
+ * - title_attributes: Same as attributes, except applied to the main title
+ *   tag that appears in the template.
+ * - title_prefix: Additional output populated by modules, intended to be
+ *   displayed in front of the main title tag that appears in the template.
+ * - title_suffix: Additional output populated by modules, intended to be
+ *   displayed after the main title tag that appears in the template.
+ *
+ * @see template_preprocess_block()
+ *
+ * @ingroup themeable
+ */
+#}
+<div{{ attributes }}>
+  {{ title_prefix }}
+  {% if label %}
+    <h2{{ title_attributes }}>{{ label }}</h2>
+  {% endif %}
+  {{ title_suffix }}
+  {% block content %}
+    {{ content }}
+  {% endblock %}
+</div>

web/core/modules/block/tests/fixtures/update/block.block.missing_schema.yml

@@ -0,0 +1,28 @@
+uuid: 1a6c0f14-78dc-4ede-bade-b8ce83881453
+langcode: en
+status: true
+dependencies:
+  module:
+    - block_test
+    - system
+  theme:
+    - bartik
+id: missing_schema
+theme: bartik
+region: sidebar_first
+weight: 0
+provider: null
+plugin: system_branding_block
+settings:
+  id: system_branding_block
+  label: 'Test missing schema on conditions'
+  provider: system
+  label_display: visible
+  use_site_logo: true
+  use_site_name: true
+  use_site_slogan: true
+visibility:
+  missing_schema:
+    id: missing_schema
+    negate: 0
+    context_mapping: {  }

web/core/modules/block/tests/fixtures/update/drupal-8.block-test-enabled-missing-schema.php

@@ -0,0 +1,49 @@
+<?php
+
+/**
+ * @file
+ * Partial database to mimic the installation of the block_test module.
+ */
+
+use Drupal\Core\Database\Database;
+use Symfony\Component\Yaml\Yaml;
+
+$connection = Database::getConnection();
+
+// Set the schema version.
+$connection->insert('key_value')
+  ->fields([
+    'collection' => 'system.schema',
+    'name' => 'block_test',
+    'value' => 'i:8000;',
+  ])
+  ->execute();
+
+// Update core.extension.
+$extensions = $connection->select('config')
+  ->fields('config', ['data'])
+  ->condition('collection', '')
+  ->condition('name', 'core.extension')
+  ->execute()
+  ->fetchField();
+$extensions = unserialize($extensions);
+$extensions['module']['block_test'] = 8000;
+$connection->update('config')
+  ->fields([
+    'data' => serialize($extensions),
+  ])
+  ->condition('collection', '')
+  ->condition('name', 'core.extension')
+  ->execute();
+
+// Install the block configuration.
+$config = file_get_contents(__DIR__ . '/block.block.missing_schema.yml');
+$config = Yaml::parse($config);
+$connection->insert('config')
+  ->fields(['data', 'name', 'collection'])
+  ->values([
+    'name' => 'block.block.missing_schema',
+    'data' => serialize($config),
+    'collection' => '',
+  ])
+  ->execute();

web/core/modules/block/tests/modules/block_test/block_test.info.yml

@@ -0,0 +1,8 @@
+name: 'Block test'
+type: module
+description: 'Provides test blocks.'
+package: Testing
+version: VERSION
+core: 8.x
+dependencies:
+  - block

web/core/modules/block/tests/modules/block_test/block_test.module

@@ -0,0 +1,62 @@
+<?php
+
+/**
+ * @file
+ * Provide test blocks.
+ */
+
+use Drupal\Core\Block\BlockPluginInterface;
+use Drupal\Core\Cache\Cache;
+
+/**
+ * Implements hook_block_alter().
+ */
+function block_test_block_alter(&$block_info) {
+  if (\Drupal::state()->get('block_test_info_alter') && isset($block_info['test_block_instantiation'])) {
+    $block_info['test_block_instantiation']['category'] = t('Custom category');
+  }
+}
+
+/**
+ * Implements hook_block_view_BASE_BLOCK_ID_alter().
+ */
+function block_test_block_view_test_cache_alter(array &$build, BlockPluginInterface $block) {
+  if (\Drupal::state()->get('block_test_view_alter_suffix') !== NULL) {
+    $build['#attributes']['foo'] = 'bar';
+  }
+  if (\Drupal::state()->get('block_test_view_alter_append_pre_render_prefix') !== NULL) {
+    $build['#pre_render'][] = 'block_test_pre_render_alter_content';
+  }
+}
+
+/**
+ * Implements hook_block_build_BASE_BLOCK_ID_alter().
+ */
+function block_test_block_build_test_cache_alter(array &$build, BlockPluginInterface $block) {
+  // Test altering cache keys, contexts, tags and max-age.
+  if (\Drupal::state()->get('block_test_block_alter_cache_key') !== NULL) {
+    $build['#cache']['keys'][] = \Drupal::state()->get('block_test_block_alter_cache_key');
+  }
+  if (\Drupal::state()->get('block_test_block_alter_cache_context') !== NULL) {
+    $build['#cache']['contexts'][] = \Drupal::state()->get('block_test_block_alter_cache_context');
+  }
+  if (\Drupal::state()->get('block_test_block_alter_cache_tag') !== NULL) {
+    $build['#cache']['tags'] = Cache::mergeTags($build['#cache']['tags'], [\Drupal::state()->get('block_test_block_alter_cache_tag')]);
+  }
+  if (\Drupal::state()->get('block_test_block_alter_cache_max_age') !== NULL) {
+    $build['#cache']['max-age'] = \Drupal::state()->get('block_test_block_alter_cache_max_age');
+  }
+
+  // Test setting #create_placeholder.
+  if (\Drupal::state()->get('block_test_block_alter_create_placeholder') !== NULL) {
+    $build['#create_placeholder'] = \Drupal::state()->get('block_test_block_alter_create_placeholder');
+  }
+}
+
+/**
+ * #pre_render callback for a block to alter its content.
+ */
+function block_test_pre_render_alter_content($build) {
+  $build['#prefix'] = 'Hiya!<br>';
+  return $build;
+}

web/core/modules/block/tests/modules/block_test/block_test.routing.yml

@@ -0,0 +1,7 @@
+block_test.test_multipleforms:
+  path: '/test-multiple-forms'
+  defaults:
+    _controller: '\Drupal\block_test\Controller\TestMultipleFormController::testMultipleForms'
+    _title: 'Multiple forms'
+  requirements:
+    _access: 'TRUE'

web/core/modules/block/tests/modules/block_test/block_test.services.yml

@@ -0,0 +1,6 @@
+services:
+  block_test.multiple_static_context:
+    class: Drupal\block_test\ContextProvider\MultipleStaticContext
+    arguments: ['@current_user', '@entity.manager']
+    tags:
+      - { name: 'context_provider' }

web/core/modules/block/tests/modules/block_test/config/install/block.block.test_block.yml

@@ -0,0 +1,17 @@
+id: test_block
+theme: stark
+weight: 0
+status: true
+langcode: en
+region: '-1'
+plugin: test_html
+settings:
+  label: 'Test HTML block'
+  provider: block_test
+  label_display: 'hidden'
+dependencies:
+  module:
+    - block_test
+  theme:
+    - classy
+visibility: {  }

web/core/modules/block/tests/modules/block_test/config/schema/block_test.schema.yml

@@ -0,0 +1,10 @@
+block.settings.test_block_instantiation:
+  type: block_settings
+  label: 'Test block instantiation settings'
+  mapping:
+    display_message:
+      type: string
+      label: 'Message text'
+
+condition.plugin.baloney_spam:
+  type: condition.plugin

web/core/modules/block/tests/modules/block_test/src/ContextProvider/MultipleStaticContext.php

@@ -0,0 +1,73 @@
+<?php
+
+namespace Drupal\block_test\ContextProvider;
+
+use Drupal\Core\Cache\CacheableMetadata;
+use Drupal\Core\Entity\EntityManagerInterface;
+use Drupal\Core\Plugin\Context\Context;
+use Drupal\Core\Plugin\Context\ContextDefinition;
+use Drupal\Core\Plugin\Context\ContextProviderInterface;
+use Drupal\Core\Session\AccountInterface;
+
+/**
+ * Sets multiple contexts for a static value.
+ */
+class MultipleStaticContext implements ContextProviderInterface {
+
+  /**
+   * The current user.
+   *
+   * @var \Drupal\Core\Session\AccountInterface
+   */
+  protected $account;
+
+  /**
+   * The user storage.
+   *
+   * @var \Drupal\user\UserStorageInterface
+   */
+  protected $userStorage;
+
+  /**
+   * Constructs a new MultipleStaticContext.
+   *
+   * @param \Drupal\Core\Session\AccountInterface $account
+   *   The current user.
+   * @param \Drupal\Core\Entity\EntityManagerInterface $entity_manager
+   *   The entity manager.
+   */
+  public function __construct(AccountInterface $account, EntityManagerInterface $entity_manager) {
+    $this->account = $account;
+    $this->userStorage = $entity_manager->getStorage('user');
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function getRuntimeContexts(array $unqualified_context_ids) {
+    $current_user = $this->userStorage->load($this->account->id());
+
+    $context1 = new Context(new ContextDefinition('entity:user', 'User 1'), $current_user);
+
+    $context2 = new Context(new ContextDefinition('entity:user', 'User 2'), $current_user);
+
+    $cacheability = new CacheableMetadata();
+    $cacheability->setCacheContexts(['user']);
+
+    $context1->addCacheableDependency($cacheability);
+    $context2->addCacheableDependency($cacheability);
+
+    return [
+      'user1' => $context1,
+      'user2' => $context2,
+    ];
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function getAvailableContexts() {
+    return $this->getRuntimeContexts([]);
+  }
+
+}

web/core/modules/block/tests/modules/block_test/src/Controller/TestMultipleFormController.php

@@ -0,0 +1,39 @@
+<?php
+
+namespace Drupal\block_test\Controller;
+
+use Drupal\Core\Controller\ControllerBase;
+use Drupal\Core\Form\FormState;
+
+/**
+ * Controller for block_test module
+ */
+class TestMultipleFormController extends ControllerBase {
+
+  public function testMultipleForms() {
+    $form_state = new FormState();
+    $build = [
+      'form1' => $this->formBuilder()->buildForm('\Drupal\block_test\Form\TestForm', $form_state),
+      'form2' => $this->formBuilder()->buildForm('\Drupal\block_test\Form\FavoriteAnimalTestForm', $form_state),
+    ];
+
+    // Output all attached placeholders trough drupal_set_message(), so we can
+    // see if there's only one in the tests.
+    $post_render_callable = function ($elements) {
+      $matches = [];
+      preg_match_all('<form\s(.*?)action="(.*?)"(.*)>', $elements, $matches);
+
+      $action_values = $matches[2];
+
+      foreach ($action_values as $action_value) {
+        drupal_set_message('Form action: ' . $action_value);
+      }
+      return $elements;
+    };
+
+    $build['#post_render'] = [$post_render_callable];
+
+    return $build;
+  }
+
+}

web/core/modules/block/tests/modules/block_test/src/Form/FavoriteAnimalTestForm.php

@@ -0,0 +1,41 @@
+<?php
+
+namespace Drupal\block_test\Form;
+
+use Drupal\Core\Form\FormBase;
+use Drupal\Core\Form\FormStateInterface;
+
+class FavoriteAnimalTestForm extends FormBase {
+
+  /**
+   * {@inheritdoc}
+   */
+  public function getFormId() {
+    return 'block_test_form_favorite_animal_test';
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function buildForm(array $form, FormStateInterface $form_state) {
+    $form['favorite_animal'] = [
+      '#type' => 'textfield',
+      '#title' => $this->t('Your favorite animal.')
+    ];
+
+    $form['submit_animal'] = [
+      '#type' => 'submit',
+      '#value' => $this->t('Submit your chosen animal'),
+    ];
+
+    return $form;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function submitForm(array &$form, FormStateInterface $form_state) {
+    drupal_set_message($this->t('Your favorite animal is: @favorite_animal', ['@favorite_animal' => $form['favorite_animal']['#value']]));
+  }
+
+}

web/core/modules/block/tests/modules/block_test/src/Form/TestForm.php

@@ -0,0 +1,50 @@
+<?php
+
+namespace Drupal\block_test\Form;
+
+use Drupal\Core\Form\FormBase;
+use Drupal\Core\Form\FormStateInterface;
+
+class TestForm extends FormBase {
+
+  /**
+   * {@inheritdoc}
+   */
+  public function getFormId() {
+    return 'block_test_form_test';
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function buildForm(array $form, FormStateInterface $form_state) {
+    $form['email'] = [
+      '#type' => 'email',
+      '#title' => $this->t('Your .com email address.')
+    ];
+
+    $form['show'] = [
+      '#type' => 'submit',
+      '#value' => $this->t('Submit'),
+    ];
+
+    return $form;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function validateForm(array &$form, FormStateInterface $form_state) {
+    if (strpos($form_state->getValue('email'), '.com') === FALSE) {
+      $form_state->setErrorByName('email', $this->t('This is not a .com email address.'));
+    }
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function submitForm(array &$form, FormStateInterface $form_state) {
+    drupal_set_message($this->t('Your email address is @email', ['@email' => $form['email']['#value']]));
+  }
+
+}

web/core/modules/block/tests/modules/block_test/src/Plugin/Block/TestAccessBlock.php

@@ -0,0 +1,78 @@
+<?php
+
+namespace Drupal\block_test\Plugin\Block;
+
+use Drupal\Core\Access\AccessResult;
+use Drupal\Core\Block\BlockBase;
+use Drupal\Core\Cache\Cache;
+use Drupal\Core\Plugin\ContainerFactoryPluginInterface;
+use Drupal\Core\Session\AccountInterface;
+use Drupal\Core\State\StateInterface;
+use Symfony\Component\DependencyInjection\ContainerInterface;
+
+/**
+ * Provides a block to test access.
+ *
+ * @Block(
+ *   id = "test_access",
+ *   admin_label = @Translation("Test block access")
+ * )
+ */
+class TestAccessBlock extends BlockBase implements ContainerFactoryPluginInterface {
+
+  /**
+   * Tests the test access block.
+   *
+   *
+   * @param array $configuration
+   *   The plugin configuration, i.e. an array with configuration values keyed
+   *   by configuration option name. The special key 'context' may be used to
+   *   initialize the defined contexts by setting it to an array of context
+   *   values keyed by context names.
+   * @param string $plugin_id
+   *   The plugin_id for the plugin instance.
+   * @param mixed $plugin_definition
+   *   The plugin implementation definition.
+   * @param \Drupal\Core\State\StateInterface $state
+   *   The state.
+   */
+  public function __construct(array $configuration, $plugin_id, $plugin_definition, StateInterface $state) {
+    parent::__construct($configuration, $plugin_id, $plugin_definition);
+
+    $this->state = $state;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public static function create(ContainerInterface $container, array $configuration, $plugin_id, $plugin_definition) {
+    return new static(
+      $configuration,
+      $plugin_id,
+      $plugin_definition,
+      $container->get('state')
+    );
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  protected function blockAccess(AccountInterface $account) {
+    return $this->state->get('test_block_access', FALSE) ? AccessResult::allowed()->setCacheMaxAge(0) : AccessResult::forbidden()->setCacheMaxAge(0);
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function build() {
+    return ['#markup' => 'Hello test world'];
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function getCacheMaxAge() {
+    return Cache::PERMANENT;
+  }
+
+}

web/core/modules/block/tests/modules/block_test/src/Plugin/Block/TestBlockInstantiation.php

@@ -0,0 +1,64 @@
+<?php
+
+namespace Drupal\block_test\Plugin\Block;
+
+use Drupal\Core\Access\AccessResult;
+use Drupal\Core\Block\BlockBase;
+use Drupal\Core\Form\FormStateInterface;
+use Drupal\Core\Session\AccountInterface;
+
+/**
+ * Provides a basic block for testing block instantiation and configuration.
+ *
+ * @Block(
+ *   id = "test_block_instantiation",
+ *   admin_label = @Translation("Display message")
+ * )
+ */
+class TestBlockInstantiation extends BlockBase {
+
+  /**
+   * {@inheritdoc}
+   */
+  public function defaultConfiguration() {
+    return array(
+      'display_message' => 'no message set',
+    );
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  protected function blockAccess(AccountInterface $account) {
+    return AccessResult::allowedIfHasPermission($account, 'access content');
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function blockForm($form, FormStateInterface $form_state) {
+    $form['display_message'] = array(
+      '#type' => 'textfield',
+      '#title' => $this->t('Display message'),
+      '#default_value' => $this->configuration['display_message'],
+    );
+    return $form;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function blockSubmit($form, FormStateInterface $form_state) {
+    $this->configuration['display_message'] = $form_state->getValue('display_message');
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function build() {
+    return array(
+      '#children' => $this->configuration['display_message'],
+    );
+  }
+
+}

web/core/modules/block/tests/modules/block_test/src/Plugin/Block/TestCacheBlock.php

@@ -0,0 +1,44 @@
+<?php
+
+namespace Drupal\block_test\Plugin\Block;
+
+use Drupal\Core\Block\BlockBase;
+
+/**
+ * Provides a block to test caching.
+ *
+ * @Block(
+ *   id = "test_cache",
+ *   admin_label = @Translation("Test block caching")
+ * )
+ */
+class TestCacheBlock extends BlockBase {
+
+  /**
+   * {@inheritdoc}
+   */
+  public function build() {
+    $content = \Drupal::state()->get('block_test.content');
+
+    $build = array();
+    if (!empty($content)) {
+      $build['#markup'] = $content;
+    }
+    return $build;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function getCacheContexts() {
+    return \Drupal::state()->get('block_test.cache_contexts', []);
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function getCacheMaxAge() {
+    return \Drupal::state()->get('block_test.cache_max_age', parent::getCacheMaxAge());
+  }
+
+}

web/core/modules/block/tests/modules/block_test/src/Plugin/Block/TestContextAwareBlock.php

@@ -0,0 +1,46 @@
+<?php
+
+namespace Drupal\block_test\Plugin\Block;
+
+use Drupal\Core\Block\BlockBase;
+use Drupal\Core\Session\AccountInterface;
+use Drupal\user\UserInterface;
+
+/**
+ * Provides a context-aware block.
+ *
+ * @Block(
+ *   id = "test_context_aware",
+ *   admin_label = @Translation("Test context-aware block"),
+ *   context = {
+ *     "user" = @ContextDefinition("entity:user", required = FALSE)
+ *   }
+ * )
+ */
+class TestContextAwareBlock extends BlockBase {
+
+  /**
+   * {@inheritdoc}
+   */
+  public function build() {
+    /** @var $user \Drupal\user\UserInterface */
+    $user = $this->getContextValue('user');
+    return array(
+      '#prefix' => '<div id="' . $this->getPluginId() . '--username">',
+      '#suffix' => '</div>',
+      '#markup' => $user ? $user->getUsername() : 'No context mapping selected.' ,
+    );
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  protected function blockAccess(AccountInterface $account) {
+    if ($this->getContextValue('user') instanceof UserInterface) {
+      drupal_set_message('User context found.');
+    }
+
+    return parent::blockAccess($account);
+  }
+
+}

web/core/modules/block/tests/modules/block_test/src/Plugin/Block/TestContextAwareUnsatisfiedBlock.php

@@ -0,0 +1,29 @@
+<?php
+
+namespace Drupal\block_test\Plugin\Block;
+
+use Drupal\Core\Block\BlockBase;
+
+/**
+ * Provides a context-aware block.
+ *
+ * @Block(
+ *   id = "test_context_aware_unsatisfied",
+ *   admin_label = @Translation("Test context-aware unsatisfied block"),
+ *   context = {
+ *     "user" = @ContextDefinition("entity:foobar")
+ *   }
+ * )
+ */
+class TestContextAwareUnsatisfiedBlock extends BlockBase {
+
+  /**
+   * {@inheritdoc}
+   */
+  public function build() {
+    return [
+      '#markup' => 'test',
+    ];
+  }
+
+}

web/core/modules/block/tests/modules/block_test/src/Plugin/Block/TestFormBlock.php

@@ -0,0 +1,24 @@
+<?php
+
+namespace Drupal\block_test\Plugin\Block;
+
+use Drupal\Core\Block\BlockBase;
+
+/**
+ * Provides a block to test caching.
+ *
+ * @Block(
+ *   id = "test_form_in_block",
+ *   admin_label = @Translation("Test form block caching")
+ * )
+ */
+class TestFormBlock extends BlockBase {
+
+  /**
+   * {@inheritdoc}
+   */
+  public function build() {
+    return \Drupal::formBuilder()->getForm('Drupal\block_test\Form\TestForm');
+  }
+
+}

web/core/modules/block/tests/modules/block_test/src/Plugin/Block/TestHtmlBlock.php

@@ -0,0 +1,27 @@
+<?php
+
+namespace Drupal\block_test\Plugin\Block;
+
+use Drupal\Core\Block\BlockBase;
+
+/**
+ * Provides a block to test HTML.
+ *
+ * @Block(
+ *   id = "test_html",
+ *   admin_label = @Translation("Test HTML block")
+ * )
+ */
+class TestHtmlBlock extends BlockBase {
+
+  /**
+   * {@inheritdoc}
+   */
+  public function build() {
+    return array(
+      '#attributes' => \Drupal::state()->get('block_test.attributes'),
+      '#children' => \Drupal::state()->get('block_test.content'),
+    );
+  }
+
+}

web/core/modules/block/tests/modules/block_test/src/Plugin/Block/TestMultipleFormsBlock.php

@@ -0,0 +1,27 @@
+<?php
+
+namespace Drupal\block_test\Plugin\Block;
+
+use Drupal\Core\Block\BlockBase;
+
+/**
+ * Provides a block with multiple forms.
+ *
+ * @Block(
+ *   id = "test_multiple_forms_block",
+ *   forms = {
+ *     "secondary" = "\Drupal\block_test\PluginForm\EmptyBlockForm"
+ *   },
+ *   admin_label = @Translation("Multiple forms test block")
+ * )
+ */
+class TestMultipleFormsBlock extends BlockBase {
+
+  /**
+   * {@inheritdoc}
+   */
+  public function build() {
+    return [];
+  }
+
+}

web/core/modules/block/tests/modules/block_test/src/Plugin/Block/TestSettingsValidationBlock.php

@@ -0,0 +1,41 @@
+<?php
+
+namespace Drupal\block_test\Plugin\Block;
+
+use Drupal\Core\Block\BlockBase;
+use Drupal\Core\Form\FormStateInterface;
+
+/**
+ * Provides a test settings validation block.
+ *
+ * @Block(
+ *  id = "test_settings_validation",
+ *  admin_label = @Translation("Test settings validation block"),
+ * )
+ */
+class TestSettingsValidationBlock extends BlockBase {
+
+  /**
+   * {@inheritdoc}
+   */
+  public function blockForm($form, FormStateInterface $form_state) {
+    return ['digits' => ['#type' => 'textfield']] + $form;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function blockValidate($form, FormStateInterface $form_state) {
+    if (!ctype_digit($form_state->getValue('digits'))) {
+      $form_state->setErrorByName('digits', $this->t('Only digits are allowed'));
+    }
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function build() {
+    return ['#markup' => 'foo'];
+  }
+
+}

web/core/modules/block/tests/modules/block_test/src/Plugin/Block/TestXSSTitleBlock.php

@@ -0,0 +1,14 @@
+<?php
+
+namespace Drupal\block_test\Plugin\Block;
+
+/**
+ * Provides a block to test XSS in title.
+ *
+ * @Block(
+ *   id = "test_xss_title",
+ *   admin_label = "<script>alert('XSS subject');</script>"
+ * )
+ */
+class TestXSSTitleBlock extends TestCacheBlock {
+}

web/core/modules/block/tests/modules/block_test/src/Plugin/Condition/BaloneySpam.php

@@ -0,0 +1,31 @@
+<?php
+
+namespace Drupal\block_test\Plugin\Condition;
+
+use Drupal\Core\Condition\ConditionPluginBase;
+
+/**
+ * Provides a 'baloney_spam' condition.
+ *
+ * @Condition(
+ *   id = "baloney_spam",
+ *   label = @Translation("Baloney spam"),
+ * )
+ */
+class BaloneySpam extends ConditionPluginBase {
+
+  /**
+   * {@inheritdoc}
+   */
+  public function evaluate() {
+    return TRUE;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function summary() {
+    return 'Summary';
+  }
+
+}

web/core/modules/block/tests/modules/block_test/src/Plugin/Condition/MissingSchema.php

@@ -0,0 +1,31 @@
+<?php
+
+namespace Drupal\block_test\Plugin\Condition;
+
+use Drupal\Core\Condition\ConditionPluginBase;
+
+/**
+ * Provides a 'missing_schema' condition.
+ *
+ * @Condition(
+ *   id = "missing_schema",
+ *   label = @Translation("Missing schema"),
+ * )
+ */
+class MissingSchema extends ConditionPluginBase {
+
+  /**
+   * {@inheritdoc}
+   */
+  public function evaluate() {
+    return FALSE;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function summary() {
+    return 'Summary';
+  }
+
+}

web/core/modules/block/tests/modules/block_test/src/PluginForm/EmptyBlockForm.php

@@ -0,0 +1,27 @@
+<?php
+
+namespace Drupal\block_test\PluginForm;
+
+use Drupal\Core\Form\FormStateInterface;
+use Drupal\Core\Plugin\PluginFormBase;
+
+/**
+ * Provides a form for a block that is empty.
+ */
+class EmptyBlockForm extends PluginFormBase {
+
+  /**
+   * {@inheritdoc}
+   */
+  public function buildConfigurationForm(array $form, FormStateInterface $form_state) {
+    return $form;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function submitConfigurationForm(array &$form, FormStateInterface $form_state) {
+    // Intentionally empty.
+  }
+
+}

web/core/modules/block/tests/modules/block_test/themes/block_test_specialchars_theme/block_test_specialchars_theme.info.yml

@@ -0,0 +1,7 @@
+name: '<"Cat" & ''Mouse''>'
+type: theme
+description: 'Theme for testing special characters in block admin.'
+core: 8.x
+regions:
+  content: Content
+  help: Help

web/core/modules/block/tests/modules/block_test/themes/block_test_theme/block_test_theme.info.yml

@@ -0,0 +1,16 @@
+name: 'Block test theme'
+type: theme
+description: 'Theme for testing the block system'
+version: VERSION
+core: 8.x
+regions:
+  sidebar_first: 'Left sidebar'
+  sidebar_second: 'Right sidebar'
+  content: Content
+  header: Header
+  footer: Footer
+  highlighted: Highlighted
+  help: Help
+regions_hidden:
+  - sidebar_first
+  - sidebar_second

web/core/modules/block/tests/modules/block_test_views/block_test_views.info.yml

@@ -0,0 +1,9 @@
+name: 'Block test views'
+type: module
+description: 'Provides a view and block to test block displays in views.'
+package: Testing
+version: VERSION
+core: 8.x
+dependencies:
+  - block
+  - views

web/core/modules/block/tests/modules/block_test_views/test_views/views.view.test_view_block.yml

@@ -0,0 +1,45 @@
+langcode: en
+status: true
+dependencies: {  }
+id: test_view_block
+label: test_view_block
+module: views
+description: ''
+tag: ''
+base_table: views_test_data
+base_field: id
+core: 8.x
+display:
+  default:
+    display_plugin: default
+    id: default
+    display_title: Master
+    position: null
+    display_options:
+      access:
+        type: none
+      cache:
+        type: tag
+      query:
+        type: views_query
+      exposed_form:
+        type: basic
+      pager:
+        type: some
+        options:
+          items_per_page: 5
+      style:
+        type: default
+      row:
+        type: fields
+      fields:
+        name:
+          id: name
+          table: views_test_data
+          field: name
+      title: test_view_block
+  block_1:
+    display_plugin: block
+    id: block_1
+    display_title: Block
+    position: null

web/core/modules/block/tests/modules/block_test_views/test_views/views.view.test_view_block2.yml

@@ -0,0 +1,57 @@
+langcode: en
+status: true
+dependencies:
+  module:
+    - user
+id: test_view_block2
+label: test_view_block2
+module: views
+description: ''
+tag: ''
+base_table: views_test_data
+base_field: id
+core: 8.x
+display:
+  default:
+    display_plugin: default
+    id: default
+    display_title: Master
+    position: null
+    display_options:
+      access:
+        type: perm
+      cache:
+        type: tag
+      query:
+        type: views_query
+      exposed_form:
+        type: basic
+      pager:
+        type: some
+        options:
+          items_per_page: 5
+      style:
+        type: default
+      row:
+        type: fields
+      fields:
+        name:
+          id: name
+          table: views_test_data
+          field: name
+      title: test_view_block2
+  block_1:
+    display_plugin: block
+    id: block_1
+    display_title: Block
+    position: null
+  block_2:
+    display_plugin: block
+    id: block_2
+    display_title: Block
+    position: null
+  block_3:
+    display_plugin: block
+    id: block_3
+    display_title: Block
+    position: null

web/core/modules/block/tests/src/Kernel/BlockConfigSchemaTest.php

@@ -0,0 +1,93 @@
+<?php
+
+namespace Drupal\Tests\block\Kernel;
+
+use Drupal\block\Entity\Block;
+use Drupal\config\Tests\SchemaCheckTestTrait;
+use Drupal\KernelTests\KernelTestBase;
+
+/**
+ * Tests the block config schema.
+ *
+ * @group block
+ */
+class BlockConfigSchemaTest extends KernelTestBase {
+
+  use SchemaCheckTestTrait;
+
+  /**
+   * {@inheritdoc}
+   */
+  public static $modules = array(
+    'block',
+    'aggregator',
+    'book',
+    'block_content',
+    'comment',
+    'forum',
+    'node',
+    'statistics',
+    // BlockManager->getModuleName() calls system_get_info().
+    'system',
+    'taxonomy',
+    'user',
+    'text',
+  );
+
+  /**
+   * The typed config manager.
+   *
+   * @var \Drupal\Core\Config\TypedConfigManagerInterface
+   */
+  protected $typedConfig;
+
+  /**
+   * The block manager.
+   *
+   * @var \Drupal\Core\Block\BlockManagerInterface
+   */
+  protected $blockManager;
+
+  /**
+   * {@inheritdoc}
+   */
+  protected function setUp() {
+    parent::setUp();
+
+    $this->typedConfig = \Drupal::service('config.typed');
+    $this->blockManager = \Drupal::service('plugin.manager.block');
+    $this->installEntitySchema('block_content');
+    $this->installEntitySchema('taxonomy_term');
+    $this->installEntitySchema('node');
+    $this->installSchema('book', array('book'));
+  }
+
+  /**
+   * Tests the block config schema for block plugins.
+   */
+  public function testBlockConfigSchema() {
+    foreach ($this->blockManager->getDefinitions() as $block_id => $definition) {
+      $id = strtolower($this->randomMachineName());
+      $block = Block::create(array(
+        'id' => $id,
+        'theme' => 'classy',
+        'weight' => 00,
+        'status' => TRUE,
+        'region' => 'content',
+        'plugin' => $block_id,
+        'settings' => array(
+          'label' => $this->randomMachineName(),
+          'provider' => 'system',
+          'label_display' => FALSE,
+        ),
+        'visibility' => array(),
+      ));
+      $block->save();
+
+      $config = $this->config("block.block.$id");
+      $this->assertEqual($config->get('id'), $id);
+      $this->assertConfigSchema($this->typedConfig, $config->getName(), $config->get());
+    }
+  }
+
+}

web/core/modules/block/tests/src/Kernel/BlockInterfaceTest.php

@@ -0,0 +1,103 @@
+<?php
+
+namespace Drupal\Tests\block\Kernel;
+
+use Drupal\Core\Form\FormState;
+use Drupal\block\BlockInterface;
+use Drupal\KernelTests\KernelTestBase;
+
+/**
+ * Tests that the block plugin can work properly without a supporting entity.
+ *
+ * @group block
+ */
+class BlockInterfaceTest extends KernelTestBase {
+
+  public static $modules = array('system', 'block', 'block_test', 'user');
+
+  /**
+   * Test configuration and subsequent form() and build() method calls.
+   *
+   * This test is attempting to test the existing block plugin api and all
+   * functionality that is expected to remain consistent. The arrays that are
+   * used for comparison can change, but only to include elements that are
+   * contained within BlockBase or the plugin being tested. Likely these
+   * comparison arrays should get smaller, not larger, as more form/build
+   * elements are moved into a more suitably responsible class.
+   *
+   * Instantiation of the plugin is the primary element being tested here. The
+   * subsequent method calls are just attempting to cause a failure if a
+   * dependency outside of the plugin configuration is required.
+   */
+  public function testBlockInterface() {
+    $manager = $this->container->get('plugin.manager.block');
+    $configuration = array(
+      'label' => 'Custom Display Message',
+    );
+    $expected_configuration = array(
+      'id' => 'test_block_instantiation',
+      'label' => 'Custom Display Message',
+      'provider' => 'block_test',
+      'label_display' => BlockInterface::BLOCK_LABEL_VISIBLE,
+      'display_message' => 'no message set',
+    );
+    // Initial configuration of the block at construction time.
+    /** @var $display_block \Drupal\Core\Block\BlockPluginInterface */
+    $display_block = $manager->createInstance('test_block_instantiation', $configuration);
+    $this->assertIdentical($display_block->getConfiguration(), $expected_configuration, 'The block was configured correctly.');
+
+    // Updating an element of the configuration.
+    $display_block->setConfigurationValue('display_message', 'My custom display message.');
+    $expected_configuration['display_message'] = 'My custom display message.';
+    $this->assertIdentical($display_block->getConfiguration(), $expected_configuration, 'The block configuration was updated correctly.');
+    $definition = $display_block->getPluginDefinition();
+
+    $expected_form = array(
+      'provider' => array(
+        '#type' => 'value',
+        '#value' => 'block_test',
+      ),
+      'admin_label' => array(
+        '#type' => 'item',
+        '#title' => t('Block description'),
+        '#plain_text' => $definition['admin_label'],
+      ),
+      'label' => array(
+        '#type' => 'textfield',
+        '#title' => 'Title',
+        '#maxlength' => 255,
+        '#default_value' => 'Custom Display Message',
+        '#required' => TRUE,
+      ),
+      'label_display' => array(
+        '#type' => 'checkbox',
+        '#title' => 'Display title',
+        '#default_value' => TRUE,
+        '#return_value' => 'visible',
+      ),
+      'context_mapping' => array(),
+      'display_message' => array(
+        '#type' => 'textfield',
+        '#title' => t('Display message'),
+        '#default_value' => 'My custom display message.',
+      ),
+    );
+    $form_state = new FormState();
+    // Ensure there are no form elements that do not belong to the plugin.
+    $actual_form = $display_block->buildConfigurationForm(array(), $form_state);
+    // Remove the visibility sections, as that just tests condition plugins.
+    unset($actual_form['visibility'], $actual_form['visibility_tabs']);
+    $this->assertIdentical($this->castSafeStrings($actual_form), $this->castSafeStrings($expected_form), 'Only the expected form elements were present.');
+
+    $expected_build = array(
+      '#children' => 'My custom display message.',
+    );
+    // Ensure the build array is proper.
+    $this->assertIdentical($display_block->build(), $expected_build, 'The plugin returned the appropriate build array.');
+
+    // Ensure the machine name suggestion is correct. In truth, this is actually
+    // testing BlockBase's implementation, not the interface itself.
+    $this->assertIdentical($display_block->getMachineNameSuggestion(), 'displaymessage', 'The plugin returned the expected machine name suggestion.');
+  }
+
+}