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

core/modules/user/src/Plugin/Action/AddRoleUser.php

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+<?php
+
+/**
+ * @file
+ * Contains \Drupal\user\Plugin\Action\AddRoleUser.
+ */
+
+namespace Drupal\user\Plugin\Action;
+
+use Drupal\Core\Access\AccessResult;
+use Drupal\Core\Session\AccountInterface;
+use Drupal\user\Plugin\Action\ChangeUserRoleBase;
+
+/**
+ * Adds a role to a user.
+ *
+ * @Action(
+ *   id = "user_add_role_action",
+ *   label = @Translation("Add a role to the selected users"),
+ *   type = "user"
+ * )
+ */
+class AddRoleUser extends ChangeUserRoleBase {
+
+  /**
+   * {@inheritdoc}
+   */
+  public function execute($account = NULL) {
+    $rid = $this->configuration['rid'];
+    // Skip adding the role to the user if they already have it.
+    if ($account !== FALSE && !$account->hasRole($rid)) {
+      // For efficiency manually save the original account before applying
+      // any changes.
+      $account->original = clone $account;
+      $account->addRole($rid);
+      $account->save();
+    }
+  }
+
+}

core/modules/user/src/Plugin/Action/BlockUser.php

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+<?php
+
+/**
+ * @file
+ * Contains \Drupal\user\Plugin\Action\BlockUser.
+ */
+
+namespace Drupal\user\Plugin\Action;
+
+use Drupal\Core\Action\ActionBase;
+use Drupal\Core\Session\AccountInterface;
+
+/**
+ * Blocks a user.
+ *
+ * @Action(
+ *   id = "user_block_user_action",
+ *   label = @Translation("Block the selected users"),
+ *   type = "user"
+ * )
+ */
+class BlockUser extends ActionBase {
+
+  /**
+   * {@inheritdoc}
+   */
+  public function execute($account = NULL) {
+    // Skip blocking user if they are already blocked.
+    if ($account !== FALSE && $account->isActive()) {
+      // For efficiency manually save the original account before applying any
+      // changes.
+      $account->original = clone $account;
+      $account->block();
+      $account->save();
+    }
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function access($object, AccountInterface $account = NULL, $return_as_object = FALSE) {
+    /** @var \Drupal\user\UserInterface $object */
+    $access = $object->status->access('edit', $account, TRUE)
+      ->andIf($object->access('update', $account, TRUE));
+
+    return $return_as_object ? $access : $access->isAllowed();
+  }
+
+}

core/modules/user/src/Plugin/Action/CancelUser.php

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+<?php
+
+/**
+ * @file
+ * Contains \Drupal\user\Plugin\Action\CancelUser.
+ */
+
+namespace Drupal\user\Plugin\Action;
+
+use Drupal\Core\Action\ActionBase;
+use Drupal\Core\Plugin\ContainerFactoryPluginInterface;
+use Drupal\Core\Session\AccountInterface;
+use Drupal\user\PrivateTempStoreFactory;
+use Symfony\Component\DependencyInjection\ContainerInterface;
+
+/**
+ * Cancels a user account.
+ *
+ * @Action(
+ *   id = "user_cancel_user_action",
+ *   label = @Translation("Cancel the selected user accounts"),
+ *   type = "user",
+ *   confirm_form_route_name = "user.multiple_cancel_confirm"
+ * )
+ */
+class CancelUser extends ActionBase implements ContainerFactoryPluginInterface {
+
+  /**
+   * The tempstore factory.
+   *
+   * @var \Drupal\user\PrivateTempStoreFactory
+   */
+  protected $tempStoreFactory;
+
+  /**
+   * The current user.
+   *
+   * @var \Drupal\Core\Session\AccountInterface
+   */
+  protected $currentUser;
+
+  /**
+   * Constructs a DeleteNode 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\user\PrivateTempStoreFactory $temp_store_factory
+   *   The tempstore factory.
+   * @param AccountInterface $current_user
+   *   Current user.
+   */
+  public function __construct(array $configuration, $plugin_id, $plugin_definition, PrivateTempStoreFactory $temp_store_factory, AccountInterface $current_user) {
+    $this->currentUser = $current_user;
+    $this->tempStoreFactory = $temp_store_factory;
+
+    parent::__construct($configuration, $plugin_id, $plugin_definition);
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public static function create(ContainerInterface $container, array $configuration, $plugin_id, $plugin_definition) {
+    return new static(
+      $configuration,
+      $plugin_id,
+      $plugin_definition,
+      $container->get('user.private_tempstore'),
+      $container->get('current_user')
+    );
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function executeMultiple(array $entities) {
+    $this->tempStoreFactory->get('user_user_operations_cancel')->set($this->currentUser->id(), $entities);
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function execute($object = NULL) {
+    $this->executeMultiple(array($object));
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function access($object, AccountInterface $account = NULL, $return_as_object = FALSE) {
+    /** @var \Drupal\user\UserInterface $object */
+    return $object->access('delete', $account, $return_as_object);
+  }
+
+}

core/modules/user/src/Plugin/Action/ChangeUserRoleBase.php

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+<?php
+
+/**
+ * @file
+ * Contains \Drupal\user\Plugin\Action\ChangeUserRoleBase.
+ */
+
+namespace Drupal\user\Plugin\Action;
+
+use Drupal\Core\Action\ConfigurableActionBase;
+use Drupal\Core\Entity\DependencyTrait;
+use Drupal\Core\Entity\EntityTypeInterface;
+use Drupal\Core\Form\FormStateInterface;
+use Drupal\Core\Plugin\ContainerFactoryPluginInterface;
+use Drupal\Core\Session\AccountInterface;
+use Drupal\user\RoleInterface;
+use Symfony\Component\DependencyInjection\ContainerInterface;
+
+/**
+ * Provides a base class for operations to change a user's role.
+ */
+abstract class ChangeUserRoleBase extends ConfigurableActionBase implements ContainerFactoryPluginInterface {
+
+  use DependencyTrait;
+
+  /**
+   * The user role entity type.
+   *
+   * @var \Drupal\Core\Entity\EntityTypeInterface
+   */
+  protected $entityType;
+
+  /**
+   * {@inheritdoc}
+   */
+  public function __construct(array $configuration, $plugin_id, $plugin_definition, EntityTypeInterface $entity_type) {
+    parent::__construct($configuration, $plugin_id, $plugin_definition);
+    $this->entityType = $entity_type;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public static function create(ContainerInterface $container, array $configuration, $plugin_id, $plugin_definition) {
+    return new static(
+      $configuration,
+      $plugin_id,
+      $plugin_definition,
+      $container->get('entity.manager')->getDefinition('user_role')
+    );
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function defaultConfiguration() {
+    return array(
+      'rid' => '',
+    );
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function buildConfigurationForm(array $form, FormStateInterface $form_state) {
+    $roles = user_role_names(TRUE);
+    unset($roles[RoleInterface::AUTHENTICATED_ID]);
+    $form['rid'] = array(
+      '#type' => 'radios',
+      '#title' => t('Role'),
+      '#options' => $roles,
+      '#default_value' => $this->configuration['rid'],
+      '#required' => TRUE,
+    );
+    return $form;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function submitConfigurationForm(array &$form, FormStateInterface $form_state) {
+    $this->configuration['rid'] = $form_state->getValue('rid');
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function calculateDependencies() {
+    if (!empty($this->configuration['rid'])) {
+      $prefix = $this->entityType->getConfigPrefix() . '.';
+      $this->addDependency('config', $prefix . $this->configuration['rid']);
+    }
+    return $this->dependencies;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function access($object, AccountInterface $account = NULL, $return_as_object = FALSE) {
+    /** @var \Drupal\user\UserInterface $object */
+    $access = $object->access('update', $account, TRUE)
+      ->andIf($object->roles->access('edit', $account, TRUE));
+
+    return $return_as_object ? $access : $access->isAllowed();
+  }
+
+}

core/modules/user/src/Plugin/Action/RemoveRoleUser.php

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+<?php
+
+/**
+ * @file
+ * Contains \Drupal\user\Plugin\Action\RemoveRoleUser.
+ */
+
+namespace Drupal\user\Plugin\Action;
+
+use Drupal\Core\Access\AccessResult;
+use Drupal\Core\Session\AccountInterface;
+use Drupal\user\Plugin\Action\ChangeUserRoleBase;
+
+/**
+ * Removes a role from a user.
+ *
+ * @Action(
+ *   id = "user_remove_role_action",
+ *   label = @Translation("Remove a role from the selected users"),
+ *   type = "user"
+ * )
+ */
+class RemoveRoleUser extends ChangeUserRoleBase {
+
+  /**
+   * {@inheritdoc}
+   */
+  public function execute($account = NULL) {
+    $rid = $this->configuration['rid'];
+    // Skip removing the role from the user if they already don't have it.
+    if ($account !== FALSE && $account->hasRole($rid)) {
+      // For efficiency manually save the original account before applying
+      // any changes.
+      $account->original = clone $account;
+      $account->removeRole($rid);
+      $account->save();
+    }
+  }
+
+}

core/modules/user/src/Plugin/Action/UnblockUser.php

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+<?php
+
+/**
+ * @file
+ * Contains \Drupal\user\Plugin\Action\UnblockUser.
+ */
+
+namespace Drupal\user\Plugin\Action;
+
+use Drupal\Core\Action\ActionBase;
+use Drupal\Core\Session\AccountInterface;
+
+/**
+ * Unblocks a user.
+ *
+ * @Action(
+ *   id = "user_unblock_user_action",
+ *   label = @Translation("Unblock the selected users"),
+ *   type = "user"
+ * )
+ */
+class UnblockUser extends ActionBase {
+
+  /**
+   * {@inheritdoc}
+   */
+  public function execute($account = NULL) {
+    // Skip unblocking user if they are already unblocked.
+    if ($account !== FALSE && $account->isBlocked()) {
+      $account->activate();
+      $account->save();
+    }
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function access($object, AccountInterface $account = NULL, $return_as_object = FALSE) {
+    /** @var \Drupal\user\UserInterface $object */
+    $access = $object->status->access('edit', $account, TRUE)
+      ->andIf($object->access('update', $account, TRUE));
+
+    return $return_as_object ? $access : $access->isAllowed();
+  }
+
+}

core/modules/user/src/Plugin/Block/UserLoginBlock.php

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+<?php
+
+/**
+ * @file
+ * Contains \Drupal\user\Plugin\Block\UserLoginBlock.
+ */
+
+namespace Drupal\user\Plugin\Block;
+
+use Drupal\Core\Access\AccessResult;
+use Drupal\Core\Plugin\ContainerFactoryPluginInterface;
+use Drupal\Core\Routing\RedirectDestinationTrait;
+use Drupal\Core\Routing\RouteMatchInterface;
+use Drupal\Core\Routing\UrlGeneratorTrait;
+use Drupal\Core\Url;
+use Drupal\Core\Session\AccountInterface;
+use Drupal\Core\Block\BlockBase;
+use Symfony\Component\DependencyInjection\ContainerInterface;
+
+/**
+ * Provides a 'User login' block.
+ *
+ * @Block(
+ *   id = "user_login_block",
+ *   admin_label = @Translation("User login"),
+ *   category = @Translation("Forms")
+ * )
+ */
+class UserLoginBlock extends BlockBase implements ContainerFactoryPluginInterface {
+
+  use UrlGeneratorTrait;
+  use RedirectDestinationTrait;
+
+  /**
+   * The route match.
+   *
+   * @var \Drupal\Core\Routing\RouteMatchInterface
+   */
+  protected $routeMatch;
+
+  /**
+   * Constructs a new UserLoginBlock instance.
+   *
+   * @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\Routing\RouteMatchInterface $route_match
+   *   The route match.
+   */
+  public function __construct(array $configuration, $plugin_id, $plugin_definition, RouteMatchInterface $route_match) {
+    parent::__construct($configuration, $plugin_id, $plugin_definition);
+
+    $this->routeMatch = $route_match;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public static function create(ContainerInterface $container, array $configuration, $plugin_id, $plugin_definition) {
+    return new static(
+      $configuration,
+      $plugin_id,
+      $plugin_definition,
+      $container->get('current_route_match')
+    );
+  }
+
+
+  /**
+   * {@inheritdoc}
+   */
+  protected function blockAccess(AccountInterface $account) {
+    $route_name = $this->routeMatch->getRouteName();
+    if ($account->isAnonymous() && !in_array($route_name, array('user.register', 'user.login', 'user.logout'))) {
+      return AccessResult::allowed()
+        ->addCacheContexts(['route', 'user.roles:anonymous']);
+    }
+    return AccessResult::forbidden();
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function build() {
+    $form = \Drupal::formBuilder()->getForm('Drupal\user\Form\UserLoginForm');
+    unset($form['name']['#attributes']['autofocus']);
+    unset($form['name']['#description']);
+    unset($form['pass']['#description']);
+    $form['name']['#size'] = 15;
+    $form['pass']['#size'] = 15;
+    $form['#action'] = $this->url('<current>', [], ['query' => $this->getDestinationArray(), 'external' => FALSE]);
+    // Build action links.
+    $items = array();
+    if (\Drupal::config('user.settings')->get('register') != USER_REGISTER_ADMINISTRATORS_ONLY) {
+      $items['create_account'] = \Drupal::l($this->t('Create new account'), new Url('user.register', array(), array(
+        'attributes' => array(
+          'title' => $this->t('Create a new user account.'),
+          'class' => array('create-account-link'),
+        ),
+      )));
+    }
+    $items['request_password'] = \Drupal::l($this->t('Reset your password'), new Url('user.pass', array(), array(
+      'attributes' => array(
+        'title' => $this->t('Send password reset instructions via e-mail.'),
+        'class' => array('request-password-link'),
+      ),
+    )));
+    return array(
+      'user_login_form' => $form,
+      'user_links' => array(
+        '#theme' => 'item_list',
+        '#items' => $items,
+      ),
+    );
+  }
+
+  /**
+   * {@inheritdoc}
+   *
+   * @todo Make cacheable once https://www.drupal.org/node/2351015 lands.
+   */
+  public function getCacheMaxAge() {
+    return 0;
+  }
+
+}

core/modules/user/src/Plugin/Condition/UserRole.php

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+<?php
+
+/**
+ * @file
+ * Contains \Drupal\user\Plugin\Condition\UserRole.
+ */
+
+namespace Drupal\user\Plugin\Condition;
+
+use Drupal\Core\Condition\ConditionPluginBase;
+use Drupal\Core\Form\FormStateInterface;
+use Drupal\Core\Plugin\Context\ContextDefinition;
+
+/**
+ * Provides a 'User Role' condition.
+ *
+ * @Condition(
+ *   id = "user_role",
+ *   label = @Translation("User Role"),
+ *   context = {
+ *     "user" = @ContextDefinition("entity:user", label = @Translation("User"))
+ *   }
+ * )
+ *
+ */
+class UserRole extends ConditionPluginBase {
+
+  /**
+   * {@inheritdoc}
+   */
+  public function buildConfigurationForm(array $form, FormStateInterface $form_state) {
+    $form['roles'] = array(
+      '#type' => 'checkboxes',
+      '#title' => $this->t('When the user has the following roles'),
+      '#default_value' => $this->configuration['roles'],
+      '#options' => array_map('\Drupal\Component\Utility\SafeMarkup::checkPlain', user_role_names()),
+      '#description' => $this->t('If you select no roles, the condition will evaluate to TRUE for all users.'),
+    );
+    return parent::buildConfigurationForm($form, $form_state);
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function defaultConfiguration() {
+    return array(
+      'roles' => array(),
+    ) + parent::defaultConfiguration();
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function submitConfigurationForm(array &$form, FormStateInterface $form_state) {
+    $this->configuration['roles'] = array_filter($form_state->getValue('roles'));
+    parent::submitConfigurationForm($form, $form_state);
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function summary() {
+    // Use the role labels. They will be sanitized below.
+    $roles = array_intersect_key(user_role_names(), $this->configuration['roles']);
+    if (count($roles) > 1) {
+      $roles = implode(', ', $roles);
+    }
+    else {
+      $roles = reset($roles);
+    }
+    if (!empty($this->configuration['negate'])) {
+      return $this->t('The user is not a member of @roles', array('@roles' => $roles));
+    }
+    else {
+      return $this->t('The user is a member of @roles', array('@roles' => $roles));
+    }
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function evaluate() {
+    if (empty($this->configuration['roles']) && !$this->isNegated()) {
+      return TRUE;
+    }
+    $user = $this->getContextValue('user');
+    return (bool) array_intersect($this->configuration['roles'], $user->getRoles());
+  }
+
+}

core/modules/user/src/Plugin/EntityReferenceSelection/UserSelection.php

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+<?php
+
+/**
+ * @file
+ * Contains \Drupal\user\Plugin\EntityReferenceSelection\UserSelection.
+ */
+
+namespace Drupal\user\Plugin\EntityReferenceSelection;
+
+use Drupal\Core\Database\Connection;
+use Drupal\Core\Database\Query\SelectInterface;
+use Drupal\Core\Entity\EntityManagerInterface;
+use Drupal\Core\Entity\Plugin\EntityReferenceSelection\SelectionBase;
+use Drupal\Core\Extension\ModuleHandlerInterface;
+use Drupal\Core\Form\FormStateInterface;
+use Drupal\Core\Session\AccountInterface;
+use Drupal\user\RoleInterface;
+use Symfony\Component\DependencyInjection\ContainerInterface;
+
+/**
+ * Provides specific access control for the user entity type.
+ *
+ * @EntityReferenceSelection(
+ *   id = "default:user",
+ *   label = @Translation("User selection"),
+ *   entity_types = {"user"},
+ *   group = "default",
+ *   weight = 1
+ * )
+ */
+class UserSelection extends SelectionBase {
+
+  /**
+   * The database connection.
+   *
+   * @var \Drupal\Core\Database\Connection
+   */
+  protected $connection;
+
+  /**
+   * The user storage.
+   *
+   * @var \Drupal\user\UserStorageInterface
+   */
+  protected $userStorage;
+
+  /**
+   * Constructs a new UserSelection 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\Core\Entity\EntityManagerInterface $entity_manager
+   *   The entity manager service.
+   * @param \Drupal\Core\Extension\ModuleHandlerInterface $module_handler
+   *   The module handler service.
+   * @param \Drupal\Core\Session\AccountInterface $current_user
+   *   The current user.
+   * @param \Drupal\Core\Database\Connection $connection
+   *   The database connection.
+   */
+  public function __construct(array $configuration, $plugin_id, $plugin_definition, EntityManagerInterface $entity_manager, ModuleHandlerInterface $module_handler, AccountInterface $current_user, Connection $connection) {
+    parent::__construct($configuration, $plugin_id, $plugin_definition, $entity_manager, $module_handler, $current_user);
+
+    $this->connection = $connection;
+    $this->userStorage = $entity_manager->getStorage('user');
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public static function create(ContainerInterface $container, array $configuration, $plugin_id, $plugin_definition) {
+    return new static(
+      $configuration,
+      $plugin_id,
+      $plugin_definition,
+      $container->get('entity.manager'),
+      $container->get('module_handler'),
+      $container->get('current_user'),
+      $container->get('database')
+    );
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function buildConfigurationForm(array $form, FormStateInterface $form_state) {
+    $selection_handler_settings = $this->configuration['handler_settings'];
+
+    // Merge in default values.
+    $selection_handler_settings += array(
+      'filter' => array(
+        'type' => '_none',
+      ),
+      'include_anonymous' => TRUE,
+    );
+
+    $form['include_anonymous'] = array(
+      '#type' => 'checkbox',
+      '#title' => $this->t('Include the anonymous user.'),
+      '#default_value' => $selection_handler_settings['include_anonymous'],
+    );
+
+    // Add user specific filter options.
+    $form['filter']['type'] = array(
+      '#type' => 'select',
+      '#title' => $this->t('Filter by'),
+      '#options' => array(
+        '_none' => $this->t('- None -'),
+        'role' => $this->t('User role'),
+      ),
+      '#ajax' => TRUE,
+      '#limit_validation_errors' => array(),
+      '#default_value' => $selection_handler_settings['filter']['type'],
+    );
+
+    $form['filter']['settings'] = array(
+      '#type' => 'container',
+      '#attributes' => array('class' => array('entity_reference-settings')),
+      '#process' => array('_entity_reference_form_process_merge_parent'),
+    );
+
+    if ($selection_handler_settings['filter']['type'] == 'role') {
+      // Merge in default values.
+      $selection_handler_settings['filter'] += array(
+        'role' => NULL,
+      );
+
+      $form['filter']['settings']['role'] = array(
+        '#type' => 'checkboxes',
+        '#title' => $this->t('Restrict to the selected roles'),
+        '#required' => TRUE,
+        '#options' => array_diff_key(user_role_names(TRUE), array(RoleInterface::AUTHENTICATED_ID => RoleInterface::AUTHENTICATED_ID)),
+        '#default_value' => $selection_handler_settings['filter']['role'],
+      );
+    }
+
+    $form += parent::buildConfigurationForm($form, $form_state);
+
+    return $form;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  protected function buildEntityQuery($match = NULL, $match_operator = 'CONTAINS') {
+    $query = parent::buildEntityQuery($match, $match_operator);
+
+    // The user entity doesn't have a label column.
+    if (isset($match)) {
+      $query->condition('name', $match, $match_operator);
+    }
+
+    // Filter by role.
+    $handler_settings = $this->configuration['handler_settings'];
+    if (!empty($handler_settings['filter']['role'])) {
+      $query->condition('roles', $handler_settings['filter']['role'], 'IN');
+    }
+
+    // Adding the permission check is sadly insufficient for users: core
+    // requires us to also know about the concept of 'blocked' and 'active'.
+    if (!$this->currentUser->hasPermission('administer users')) {
+      $query->condition('status', 1);
+    }
+    return $query;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function entityQueryAlter(SelectInterface $query) {
+    // Bail out early if we do not need to match the Anonymous user.
+    $handler_settings = $this->configuration['handler_settings'];
+    if (isset($handler_settings['include_anonymous']) && !$handler_settings['include_anonymous']) {
+      return;
+    }
+
+    if ($this->currentUser->hasPermission('administer users')) {
+      // In addition, if the user is administrator, we need to make sure to
+      // match the anonymous user, that doesn't actually have a name in the
+      // database.
+      $conditions = &$query->conditions();
+      foreach ($conditions as $key => $condition) {
+        if ($key !== '#conjunction' && is_string($condition['field']) && $condition['field'] === 'users_field_data.name') {
+          // Remove the condition.
+          unset($conditions[$key]);
+
+          // Re-add the condition and a condition on uid = 0 so that we end up
+          // with a query in the form:
+          // WHERE (name LIKE :name) OR (:anonymous_name LIKE :name AND uid = 0)
+          $or = db_or();
+          $or->condition($condition['field'], $condition['value'], $condition['operator']);
+          // Sadly, the Database layer doesn't allow us to build a condition
+          // in the form ':placeholder = :placeholder2', because the 'field'
+          // part of a condition is always escaped.
+          // As a (cheap) workaround, we separately build a condition with no
+          // field, and concatenate the field and the condition separately.
+          $value_part = db_and();
+          $value_part->condition('anonymous_name', $condition['value'], $condition['operator']);
+          $value_part->compile($this->connection, $query);
+          $or->condition(db_and()
+            ->where(str_replace('anonymous_name', ':anonymous_name', (string) $value_part), $value_part->arguments() + array(':anonymous_name' => user_format_name($this->userStorage->load(0))))
+            ->condition('base_table.uid', 0)
+          );
+          $query->condition($or);
+        }
+      }
+    }
+  }
+
+}

core/modules/user/src/Plugin/Field/FieldFormatter/AuthorFormatter.php

@@ -0,0 +1,67 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\user\Plugin\Field\FieldFormatter\AuthorFormatter.
+ */
+
+namespace Drupal\user\Plugin\Field\FieldFormatter;
+
+use Drupal\Core\Access\AccessResult;
+use Drupal\Core\Entity\EntityInterface;
+use Drupal\Core\Field\FieldDefinitionInterface;
+use Drupal\Core\Field\FieldItemListInterface;
+use Drupal\Core\Field\Plugin\Field\FieldFormatter\EntityReferenceFormatterBase;
+
+/**
+ * Plugin implementation of the 'author' formatter.
+ *
+ * @FieldFormatter(
+ *   id = "author",
+ *   label = @Translation("Author"),
+ *   description = @Translation("Display the referenced author user entity."),
+ *   field_types = {
+ *     "entity_reference"
+ *   }
+ * )
+ */
+class AuthorFormatter extends EntityReferenceFormatterBase {
+
+  /**
+   * {@inheritdoc}
+   */
+  public function viewElements(FieldItemListInterface $items) {
+    $elements = array();
+
+    foreach ($this->getEntitiesToView($items) as $delta => $entity) {
+      /** @var $referenced_user \Drupal\user\UserInterface */
+      $elements[$delta] = array(
+        '#theme' => 'username',
+        '#account' => $entity,
+        '#link_options' => array('attributes' => array('rel' => 'author')),
+        '#cache' => array(
+          'tags' => $entity->getCacheTags(),
+        ),
+      );
+    }
+
+    return $elements;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public static function isApplicable(FieldDefinitionInterface $field_definition) {
+    return $field_definition->getFieldStorageDefinition()->getSetting('target_type') == 'user';
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  protected function checkAccess(EntityInterface $entity) {
+    // Always allow an entity author's username to be read, even if the current
+    // user does not have permission to view the entity author's profile.
+    return AccessResult::allowed();
+  }
+
+}

core/modules/user/src/Plugin/Field/FieldFormatter/UserNameFormatter.php

@@ -0,0 +1,94 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\user\Plugin\Field\FieldFormatter\UserNameFormatter.
+ */
+
+namespace Drupal\user\Plugin\Field\FieldFormatter;
+
+use Drupal\Core\Field\FieldDefinitionInterface;
+use Drupal\Core\Field\FieldItemListInterface;
+use Drupal\Core\Field\FormatterBase;
+use Drupal\Core\Form\FormStateInterface;
+
+/**
+ * Plugin implementation of the 'user_name' formatter.
+ *
+ * @FieldFormatter(
+ *   id = "user_name",
+ *   label = @Translation("User name"),
+ *   description = @Translation("Display the user or author name."),
+ *   field_types = {
+ *     "string"
+ *   }
+ * )
+ */
+class UserNameFormatter extends FormatterBase {
+
+  /**
+   * {@inheritdoc}
+   */
+  public static function defaultSettings() {
+    $options = parent::defaultSettings();
+
+    $options['link_to_entity'] = TRUE;
+    return $options;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function settingsForm(array $form, FormStateInterface $form_state) {
+    $form = parent::settingsForm($form, $form_state);
+
+    $form['link_to_entity'] = [
+      '#type' => 'checkbox',
+      '#title' => $this->t('Link to the user'),
+      '#default_value' => $this->getSetting('link_to_entity'),
+    ];
+
+    return $form;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function viewElements(FieldItemListInterface $items) {
+    $elements = [];
+
+    foreach ($items as $delta => $item) {
+      /** @var $user \Drupal\user\UserInterface */
+      if ($user = $item->getEntity()) {
+        if ($this->getSetting('link_to_entity')) {
+          $elements[$delta] = [
+            '#theme' => 'username',
+            '#account' => $user,
+            '#link_options' => ['attributes' => ['rel' => 'user']],
+            '#cache' => [
+              'tags' => $user->getCacheTags(),
+            ],
+          ];
+        }
+        else {
+          $elements[$delta] = [
+            '#markup' => $user->getUsername(),
+            '#cache' => [
+              'tags' => $user->getCacheTags(),
+            ],
+          ];
+        }
+      }
+    }
+
+    return $elements;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public static function isApplicable(FieldDefinitionInterface $field_definition) {
+    return $field_definition->getTargetEntityTypeId() === 'user' && $field_definition->getName() === 'name';
+  }
+
+}

core/modules/user/src/Plugin/LanguageNegotiation/LanguageNegotiationUser.php

@@ -0,0 +1,50 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\user\Plugin\LanguageNegotiation\LanguageNegotiationUser.
+ */
+
+namespace Drupal\user\Plugin\LanguageNegotiation;
+
+use Drupal\language\LanguageNegotiationMethodBase;
+use Symfony\Component\HttpFoundation\Request;
+
+/**
+ * Class for identifying language from the user preferences.
+ *
+ * @LanguageNegotiation(
+ *   id = \Drupal\user\Plugin\LanguageNegotiation\LanguageNegotiationUser::METHOD_ID,
+ *   weight = -4,
+ *   name = @Translation("User"),
+ *   description = @Translation("Follow the user's language preference.")
+ * )
+ */
+class LanguageNegotiationUser extends LanguageNegotiationMethodBase {
+
+  /**
+   * The language negotiation method id.
+   */
+  const METHOD_ID = 'language-user';
+
+  /**
+   * {@inheritdoc}
+   */
+  public function getLangcode(Request $request = NULL) {
+    $langcode = NULL;
+
+    // User preference (only for authenticated users).
+    if ($this->languageManager && $this->currentUser->isAuthenticated()) {
+      $preferred_langcode = $this->currentUser->getPreferredLangcode();
+      $default_langcode = $this->languageManager->getDefaultLanguage()->getId();
+      $languages = $this->languageManager->getLanguages();
+      if (!empty($preferred_langcode) && $preferred_langcode != $default_langcode && isset($languages[$preferred_langcode])) {
+        $langcode = $preferred_langcode;
+      }
+    }
+
+    // No language preference from the user.
+    return $langcode;
+  }
+
+}

core/modules/user/src/Plugin/LanguageNegotiation/LanguageNegotiationUserAdmin.php

@@ -0,0 +1,155 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\user\Plugin\LanguageNegotiation\LanguageNegotiationUserAdmin.
+ */
+
+namespace Drupal\user\Plugin\LanguageNegotiation;
+
+use Drupal\Core\PathProcessor\PathProcessorManager;
+use Drupal\Core\Plugin\ContainerFactoryPluginInterface;
+use Drupal\Core\Routing\AdminContext;
+use Drupal\Core\Routing\RouteMatch;
+use Drupal\Core\Routing\StackedRouteMatchInterface;
+use Drupal\language\LanguageNegotiationMethodBase;
+use Symfony\Cmf\Component\Routing\RouteObjectInterface;
+use Symfony\Component\DependencyInjection\ContainerInterface;
+use Symfony\Component\HttpFoundation\Request;
+use Symfony\Component\HttpKernel\Exception\AccessDeniedHttpException;
+use Symfony\Component\Routing\Exception\ResourceNotFoundException;
+use Symfony\Component\Routing\Matcher\UrlMatcherInterface;
+
+/**
+ * Identifies admin language from the user preferences.
+ *
+ * @LanguageNegotiation(
+ *   id = Drupal\user\Plugin\LanguageNegotiation\LanguageNegotiationUserAdmin::METHOD_ID,
+ *   types = {Drupal\Core\Language\LanguageInterface::TYPE_INTERFACE},
+ *   weight = -10,
+ *   name = @Translation("Account administration pages"),
+ *   description = @Translation("Account administration pages language setting.")
+ * )
+ */
+class LanguageNegotiationUserAdmin extends LanguageNegotiationMethodBase implements ContainerFactoryPluginInterface {
+
+  /**
+   * The language negotiation method id.
+   */
+  const METHOD_ID = 'language-user-admin';
+
+  /**
+   * The admin context.
+   *
+   * @var \Drupal\Core\Routing\AdminContext
+   */
+  protected $adminContext;
+
+  /**
+   * The router.
+   *
+   * This is only used when called from an event subscriber, before the request
+   * has been populated with the route info.
+   *
+   * @var \Symfony\Component\Routing\Matcher\UrlMatcherInterface
+   */
+  protected $router;
+
+  /**
+   * The path processor manager.
+   *
+   * @var \Drupal\Core\PathProcessor\PathProcessorManager
+   */
+  protected $pathProcessorManager;
+
+  /**
+   * The stacked route match.
+   *
+   * @var \Drupal\Core\Routing\StackedRouteMatchInterface
+   */
+  protected $stackedRouteMatch;
+
+  /**
+   * Constructs a new LanguageNegotiationUserAdmin instance.
+   *
+   * @param \Drupal\Core\Routing\AdminContext $admin_context
+   *   The admin context.
+   * @param \Symfony\Component\Routing\Matcher\UrlMatcherInterface $router
+   *   The router.
+   * @param \Drupal\Core\PathProcessor\PathProcessorManager $path_processor_manager
+   *   The path processor manager.
+   * @param \Drupal\Core\Routing\StackedRouteMatchInterface $stacked_route_match
+   *   The stacked route match.
+   */
+  public function __construct(AdminContext $admin_context, UrlMatcherInterface $router, PathProcessorManager $path_processor_manager, StackedRouteMatchInterface $stacked_route_match) {
+    $this->adminContext = $admin_context;
+    $this->router = $router;
+    $this->pathProcessorManager = $path_processor_manager;
+    $this->stackedRouteMatch = $stacked_route_match;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public static function create(ContainerInterface $container, array $configuration, $plugin_id, $plugin_definition) {
+    return new static(
+      $container->get('router.admin_context'),
+      $container->get('router'),
+      $container->get('path_processor_manager'),
+      $container->get('current_route_match')
+    );
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function getLangcode(Request $request = NULL) {
+    $langcode = NULL;
+
+    // User preference (only for administrators).
+    if ($this->currentUser->hasPermission('access administration pages') && ($preferred_admin_langcode = $this->currentUser->getPreferredAdminLangcode(FALSE)) && $this->isAdminPath($request)) {
+      $langcode = $preferred_admin_langcode;
+    }
+
+    // Not an admin, no admin language preference or not on an admin path.
+    return $langcode;
+  }
+
+  /**
+   * Checks whether the given path is an administrative one.
+   *
+   * @param \Symfony\Component\HttpFoundation\Request $request
+   *   The request object.
+   *
+   * @return bool
+   *   TRUE if the path is administrative, FALSE otherwise.
+   */
+  protected function isAdminPath(Request $request) {
+    $result = FALSE;
+    if ($request && $this->adminContext) {
+      // If called from an event subscriber, the request may not have the route
+      // object yet (it is still being built), so use the router to look up
+      // based on the path.
+      $route_match = $this->stackedRouteMatch->getRouteMatchFromRequest($request);
+      if ($route_match && !$route_object = $route_match->getRouteObject()) {
+        try {
+          // Process the path as an inbound path. This will remove any language
+          // prefixes and other path components that inbound processing would
+          // clear out, so we can attempt to load the route clearly.
+          $path = $this->pathProcessorManager->processInbound(urldecode(rtrim($request->getPathInfo(), '/')), $request);
+          $attributes = $this->router->match($path);
+        }
+        catch (ResourceNotFoundException $e) {
+          return FALSE;
+        }
+        catch (AccessDeniedHttpException $e) {
+          return FALSE;
+        }
+        $route_object = $attributes[RouteObjectInterface::ROUTE_OBJECT];
+      }
+      $result = $this->adminContext->isAdminRoute($route_object);
+    }
+    return $result;
+  }
+
+}

core/modules/user/src/Plugin/Search/UserSearch.php

@@ -0,0 +1,178 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\user\Plugin\Search\UserSearch.
+ */
+
+namespace Drupal\user\Plugin\Search;
+
+use Drupal\Core\Access\AccessResult;
+use Drupal\Core\Database\Connection;
+use Drupal\Core\Entity\EntityManagerInterface;
+use Drupal\Core\Extension\ModuleHandlerInterface;
+use Drupal\Core\Session\AccountInterface;
+use Drupal\Core\Access\AccessibleInterface;
+use Drupal\search\Plugin\SearchPluginBase;
+use Symfony\Component\DependencyInjection\ContainerInterface;
+
+/**
+ * Executes a keyword search for users against the {users} database table.
+ *
+ * @SearchPlugin(
+ *   id = "user_search",
+ *   title = @Translation("Users")
+ * )
+ */
+class UserSearch extends SearchPluginBase implements AccessibleInterface {
+
+  /**
+   * The database connection.
+   *
+   * @var \Drupal\Core\Database\Connection
+   */
+  protected $database;
+
+  /**
+   * The entity manager.
+   *
+   * @var \Drupal\Core\Entity\EntityManagerInterface
+   */
+  protected $entityManager;
+
+  /**
+   * The module handler.
+   *
+   * @var \Drupal\Core\Extension\ModuleHandlerInterface
+   */
+  protected $moduleHandler;
+
+  /**
+   * The current user.
+   *
+   * @var \Drupal\Core\Session\AccountInterface
+   */
+  protected $currentUser;
+
+  /**
+   * {@inheritdoc}
+   */
+  static public function create(ContainerInterface $container, array $configuration, $plugin_id, $plugin_definition) {
+    return new static(
+      $container->get('database'),
+      $container->get('entity.manager'),
+      $container->get('module_handler'),
+      $container->get('current_user'),
+      $configuration,
+      $plugin_id,
+      $plugin_definition
+    );
+  }
+
+  /**
+   * Creates a UserSearch object.
+   *
+   * @param Connection $database
+   *   The database connection.
+   * @param \Drupal\Core\Entity\EntityManagerInterface $entity_manager
+   *   The entity manager.
+   * @param ModuleHandlerInterface $module_handler
+   *   The module handler.
+   * @param \Drupal\Core\Session\AccountInterface $current_user
+   *   The current user.
+   * @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.
+   */
+  public function __construct(Connection $database, EntityManagerInterface $entity_manager, ModuleHandlerInterface $module_handler, AccountInterface $current_user, array $configuration, $plugin_id, $plugin_definition) {
+    $this->database = $database;
+    $this->entityManager = $entity_manager;
+    $this->moduleHandler = $module_handler;
+    $this->currentUser = $current_user;
+    parent::__construct($configuration, $plugin_id, $plugin_definition);
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function access($operation = 'view', AccountInterface $account = NULL, $return_as_object = FALSE) {
+    $result = AccessResult::allowedIf(!empty($account) && $account->hasPermission('access user profiles'))->cachePerPermissions();
+    return $return_as_object ? $result : $result->isAllowed();
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function execute() {
+    $results = array();
+    if (!$this->isSearchExecutable()) {
+      return $results;
+    }
+
+    // Process the keywords.
+    $keys = $this->keywords;
+    // Escape for LIKE matching.
+    $keys = $this->database->escapeLike($keys);
+    // Replace wildcards with MySQL/PostgreSQL wildcards.
+    $keys = preg_replace('!\*+!', '%', $keys);
+
+    // Run the query to find matching users.
+    $query = $this->database
+      ->select('users_field_data', 'users')
+      ->extend('Drupal\Core\Database\Query\PagerSelectExtender');
+    $query->fields('users', array('uid'));
+    $query->condition('default_langcode', 1);
+    if ($this->currentUser->hasPermission('administer users')) {
+      // Administrators can also search in the otherwise private email field,
+      // and they don't need to be restricted to only active users.
+      $query->fields('users', array('mail'));
+      $query->condition($query->orConditionGroup()
+        ->condition('name', '%' . $keys . '%', 'LIKE')
+        ->condition('mail', '%' . $keys . '%', 'LIKE')
+      );
+    }
+    else {
+      // Regular users can only search via usernames, and we do not show them
+      // blocked accounts.
+      $query->condition('name', '%' . $keys . '%', 'LIKE')
+        ->condition('status', 1);
+    }
+    $uids = $query
+      ->limit(15)
+      ->execute()
+      ->fetchCol();
+    $accounts = $this->entityManager->getStorage('user')->loadMultiple($uids);
+
+    foreach ($accounts as $account) {
+      $result = array(
+        'title' => $account->getUsername(),
+        'link' => $account->url('canonical', array('absolute' => TRUE)),
+      );
+      if ($this->currentUser->hasPermission('administer users')) {
+        $result['title'] .= ' (' . $account->getEmail() . ')';
+      }
+      $results[] = $result;
+    }
+
+    return $results;
+  }
+
+  /*
+   * {@inheritdoc}
+   */
+  public function getHelp() {
+    $help = array('list' => array(
+      '#theme' => 'item_list',
+      '#items' => array(
+        $this->t('User search looks for user names and partial user names. Example: mar would match usernames mar, delmar, and maryjane.'),
+        $this->t('You can use * as a wildcard within your keyword. Example: m*r would match user names mar, delmar, and elementary.'),
+      ),
+    ));
+
+    return $help;
+  }
+
+}

core/modules/user/src/Plugin/Validation/Constraint/ProtectedUserFieldConstraint.php

@@ -0,0 +1,29 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\user\Plugin\Validation\Constraint\ProtectedUserFieldConstraint.
+ */
+
+namespace Drupal\user\Plugin\Validation\Constraint;
+
+use Symfony\Component\Validator\Constraint;
+
+/**
+ * Checks if the plain text password is provided for editing a protected field.
+ *
+ * @Constraint(
+ *   id = "ProtectedUserField",
+ *   label = @Translation("Password required for protected field change", context = "Validation")
+ * )
+ */
+class ProtectedUserFieldConstraint extends Constraint {
+
+  /**
+   * Violation message.
+   *
+   * @var string
+   */
+  public $message = "Your current password is missing or incorrect; it's required to change the %name.";
+
+}

core/modules/user/src/Plugin/Validation/Constraint/ProtectedUserFieldConstraintValidator.php

@@ -0,0 +1,98 @@
+<?php
+/**
+ * @file
+ * Contains \Drupal\user\Plugin\Validation\Constraint\ProtectedUserFieldConstraintValidator.
+ */
+
+namespace Drupal\user\Plugin\Validation\Constraint;
+
+use Drupal\Core\DependencyInjection\ContainerInjectionInterface;
+use Drupal\Core\Session\AccountProxyInterface;
+use Drupal\user\UserStorageInterface;
+use Symfony\Component\DependencyInjection\ContainerInterface;
+use Symfony\Component\Validator\Constraint;
+use Symfony\Component\Validator\ConstraintValidator;
+
+/**
+ * Validates the ProtectedUserFieldConstraint constraint.
+ */
+class ProtectedUserFieldConstraintValidator extends ConstraintValidator implements ContainerInjectionInterface {
+
+  /**
+   * User storage handler.
+   *
+   * @var \Drupal\user\UserStorageInterface
+   */
+  protected $userStorage;
+
+  /**
+   * The current user.
+   *
+   * @var \Drupal\Core\Session\AccountProxyInterface
+   */
+  protected $currentUser;
+
+  /**
+   * Constructs the object.
+   *
+   * @param \Drupal\user\UserStorageInterface $user_storage
+   *   The user storage handler.
+   * @param \Drupal\Core\Session\AccountProxyInterface $current_user
+   *   The current user.
+   */
+  public function __construct(UserStorageInterface $user_storage, AccountProxyInterface $current_user) {
+    $this->userStorage = $user_storage;
+    $this->currentUser = $current_user;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public static function create(ContainerInterface $container) {
+    return new static(
+      $container->get('entity.manager')->getStorage('user'),
+      $container->get('current_user')
+    );
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function validate($items, Constraint $constraint) {
+    if (!isset($items)) {
+      return;
+    }
+    /* @var \Drupal\Core\Field\FieldItemListInterface $items */
+    $field = $items->getFieldDefinition();
+
+    /* @var \Drupal\user\UserInterface $account */
+    $account = $items->getEntity();
+    if (!isset($account) || !empty($account->_skipProtectedUserFieldConstraint)) {
+      // Looks like we are validating a field not being part of a user, or the
+      // constraint should be skipped, so do nothing.
+      return;
+    }
+
+    // Only validate for existing entities and if this is the current user.
+    if (!$account->isNew() && $account->id() == $this->currentUser->id()) {
+
+      /* @var \Drupal\user\UserInterface $account_unchanged */
+      $account_unchanged = $this->userStorage
+        ->loadUnchanged($account->id());
+
+      $changed = FALSE;
+
+      // Special case for the password, it being empty means that the existing
+      // password should not be changed, ignore empty password fields.
+      $value = $items->value;
+      if ($field->getName() != 'pass' || !empty($value)) {
+        // Compare the values of the field this is being validated on.
+        $changed = $items->getValue() != $account_unchanged->get($field->getName())->getValue();
+      }
+      if ($changed && (!$account->checkExistingPassword($account_unchanged))) {
+        $this->context->addViolation($constraint->message, array('%name' => $field->getLabel()));
+      }
+    }
+  }
+
+}

core/modules/user/src/Plugin/Validation/Constraint/UserMailRequired.php

@@ -0,0 +1,77 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\user\Plugin\Validation\Constraint\UserMailRequired.
+ */
+
+namespace Drupal\user\Plugin\Validation\Constraint;
+
+use Drupal\Component\Utility\SafeMarkup;
+use Symfony\Component\Validator\Constraint;
+use Symfony\Component\Validator\ConstraintValidatorInterface;
+use Symfony\Component\Validator\ExecutionContextInterface;
+
+/**
+ * Checks if the user's email address is provided if required.
+ *
+ * The user mail field is NOT required if account originally had no mail set
+ * and the user performing the edit has 'administer users' permission.
+ * This allows users without email address to be edited and deleted.
+ *
+ * @Constraint(
+ *   id = "UserMailRequired",
+ *   label = @Translation("User email required", context = "Validation")
+ * )
+ */
+class UserMailRequired extends Constraint implements ConstraintValidatorInterface {
+
+  /**
+   * Violation message. Use the same message as FormValidator.
+   *
+   * @var string
+   */
+  public $message = '!name field is required.';
+
+  /**
+   * @var \Symfony\Component\Validator\ExecutionContextInterface
+   */
+  protected $context;
+
+  /**
+   * {@inheritDoc}
+   */
+  public function initialize(ExecutionContextInterface $context) {
+    $this->context = $context;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function validatedBy() {
+    return get_class($this);
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function validate($items, Constraint $constraint) {
+    /** @var \Drupal\Core\Field\FieldItemListInterface $items */
+    /** @var \Drupal\user\UserInterface $account */
+    $account = $items->getEntity();
+    $existing_value = NULL;
+    if ($account->id()) {
+      $account_unchanged = \Drupal::entityManager()
+        ->getStorage('user')
+        ->loadUnchanged($account->id());
+      $existing_value = $account_unchanged->getEmail();
+    }
+
+    $required = !(!$existing_value && \Drupal::currentUser()->hasPermission('administer users'));
+
+    if ($required && (!isset($items) || $items->isEmpty())) {
+      $this->context->addViolation($this->message, array('!name' => SafeMarkup::placeholder($account->getFieldDefinition('mail')->getLabel())));
+    }
+  }
+
+}

core/modules/user/src/Plugin/Validation/Constraint/UserMailUnique.php

@@ -0,0 +1,30 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\user\Plugin\Validation\Constraint\UserMailUnique.
+ */
+
+namespace Drupal\user\Plugin\Validation\Constraint;
+
+use Symfony\Component\Validator\Constraint;
+
+/**
+ * Checks if a user's email address is unique on the site.
+ *
+ * @Constraint(
+ *   id = "UserMailUnique",
+ *   label = @Translation("User email unique", context = "Validation")
+ * )
+ */
+class UserMailUnique extends Constraint {
+
+  public $message = 'The email address %value is already taken.';
+
+  /**
+   * {@inheritdoc}
+   */
+  public function validatedBy() {
+    return '\Drupal\Core\Validation\Plugin\Validation\Constraint\UniqueFieldValueValidator';
+  }
+}

core/modules/user/src/Plugin/Validation/Constraint/UserNameConstraint.php

@@ -0,0 +1,28 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\user\Plugin\Validation\Constraint\UserNameConstraint.
+ */
+
+namespace Drupal\user\Plugin\Validation\Constraint;
+
+use Symfony\Component\Validator\Constraint;
+
+/**
+ * Checks if a value is a valid user name.
+ *
+ * @Constraint(
+ *   id = "UserName",
+ *   label = @Translation("User name", context = "Validation"),
+ * )
+ */
+class UserNameConstraint extends Constraint {
+
+  public $emptyMessage = 'You must enter a username.';
+  public $spaceBeginMessage = 'The username cannot begin with a space.';
+  public $spaceEndMessage = 'The username cannot end with a space.';
+  public $multipleSpacesMessage = 'The username cannot contain multiple spaces in a row.';
+  public $illegalMessage = 'The username contains an illegal character.';
+  public $tooLongMessage = 'The username %name is too long: it must be %max characters or less.';
+}

core/modules/user/src/Plugin/Validation/Constraint/UserNameConstraintValidator.php

@@ -0,0 +1,56 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\user\Plugin\Validation\Constraint\UserNameConstraintValidator.
+ */
+
+namespace Drupal\user\Plugin\Validation\Constraint;
+
+use Drupal\Component\Utility\Unicode;
+use Symfony\Component\Validator\Constraint;
+use Symfony\Component\Validator\ConstraintValidator;
+
+/**
+ * Validates the UserName constraint.
+ */
+class UserNameConstraintValidator extends ConstraintValidator {
+
+  /**
+   * {@inheritdoc}
+   */
+  public function validate($items, Constraint $constraint) {
+    if (!isset($items) || !$items->value) {
+      $this->context->addViolation($constraint->emptyMessage);
+      return;
+    }
+    $name = $items->first()->value;
+    if (substr($name, 0, 1) == ' ') {
+      $this->context->addViolation($constraint->spaceBeginMessage);
+    }
+    if (substr($name, -1) == ' ') {
+      $this->context->addViolation($constraint->spaceEndMessage);
+    }
+    if (strpos($name, '  ') !== FALSE) {
+      $this->context->addViolation($constraint->multipleSpacesMessage);
+    }
+    if (preg_match('/[^\x{80}-\x{F7} a-z0-9@_.\'-]/i', $name)
+      || preg_match(
+        '/[\x{80}-\x{A0}' .       // Non-printable ISO-8859-1 + NBSP
+        '\x{AD}' .                // Soft-hyphen
+        '\x{2000}-\x{200F}' .     // Various space characters
+        '\x{2028}-\x{202F}' .     // Bidirectional text overrides
+        '\x{205F}-\x{206F}' .     // Various text hinting characters
+        '\x{FEFF}' .              // Byte order mark
+        '\x{FF01}-\x{FF60}' .     // Full-width latin
+        '\x{FFF9}-\x{FFFD}' .     // Replacement characters
+        '\x{0}-\x{1F}]/u',        // NULL byte and control characters
+        $name)
+    ) {
+      $this->context->addViolation($constraint->illegalMessage);
+    }
+    if (Unicode::strlen($name) > USERNAME_MAX_LENGTH) {
+      $this->context->addViolation($constraint->tooLongMessage, array('%name' => $name, '%max' => USERNAME_MAX_LENGTH));
+    }
+  }
+}

core/modules/user/src/Plugin/Validation/Constraint/UserNameUnique.php

@@ -0,0 +1,30 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\user\Plugin\Validation\Constraint\UserNameUnique.
+ */
+
+namespace Drupal\user\Plugin\Validation\Constraint;
+
+use Symfony\Component\Validator\Constraint;
+
+/**
+ * Checks if a user name is unique on the site.
+ *
+ * @Constraint(
+ *   id = "UserNameUnique",
+ *   label = @Translation("User name unique", context = "Validation"),
+ * )
+ */
+class UserNameUnique extends Constraint {
+
+  public $message = 'The username %value is already taken.';
+
+  /**
+   * {@inheritdoc}
+   */
+  public function validatedBy() {
+    return '\Drupal\Core\Validation\Plugin\Validation\Constraint\UniqueFieldValueValidator';
+  }
+}

core/modules/user/src/Plugin/views/access/Permission.php

@@ -0,0 +1,150 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\user\Plugin\views\access\Permission.
+ */
+
+namespace Drupal\user\Plugin\views\access;
+
+use Drupal\Component\Utility\SafeMarkup;
+use Drupal\Core\Extension\ModuleHandlerInterface;
+use Drupal\Core\Form\FormStateInterface;
+use Drupal\Core\Session\AccountInterface;
+use Drupal\user\PermissionHandlerInterface;
+use Drupal\views\Plugin\CacheablePluginInterface;
+use Drupal\views\Plugin\views\access\AccessPluginBase;
+use Symfony\Component\DependencyInjection\ContainerInterface;
+use Symfony\Component\Routing\Route;
+
+/**
+ * Access plugin that provides permission-based access control.
+ *
+ * @ingroup views_access_plugins
+ *
+ * @ViewsAccess(
+ *   id = "perm",
+ *   title = @Translation("Permission"),
+ *   help = @Translation("Access will be granted to users with the specified permission string.")
+ * )
+ */
+class Permission extends AccessPluginBase implements CacheablePluginInterface {
+
+  /**
+   * Overrides Drupal\views\Plugin\Plugin::$usesOptions.
+   */
+  protected $usesOptions = TRUE;
+
+  /**
+   * The permission handler.
+   *
+   * @var \Drupal\user\PermissionHandlerInterface
+   */
+  protected $permissionHandler;
+
+  /**
+   * The module handler.
+   *
+   * @var \Drupal\Core\Extension\ModuleHandlerInterface
+   */
+  protected $moduleHandler;
+
+  /**
+   * Constructs a Permission 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\user\PermissionHandlerInterface $permission_handler
+   *   The permission handler.
+   * @param \Drupal\Core\Extension\ModuleHandlerInterface $module_handler
+   *   The module handler.
+   */
+  public function __construct(array $configuration, $plugin_id, $plugin_definition, PermissionHandlerInterface $permission_handler, ModuleHandlerInterface $module_handler) {
+    parent::__construct($configuration, $plugin_id, $plugin_definition);
+    $this->permissionHandler = $permission_handler;
+    $this->moduleHandler = $module_handler;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public static function create(ContainerInterface $container, array $configuration, $plugin_id, $plugin_definition) {
+    return new static(
+      $configuration,
+      $plugin_id,
+      $plugin_definition,
+      $container->get('user.permissions'),
+      $container->get('module_handler')
+    );
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function access(AccountInterface $account) {
+    return $account->hasPermission($this->options['perm']);
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function alterRouteDefinition(Route $route) {
+    $route->setRequirement('_permission', $this->options['perm']);
+  }
+
+  public function summaryTitle() {
+    $permissions = $this->permissionHandler->getPermissions();
+    if (isset($permissions[$this->options['perm']])) {
+      return $permissions[$this->options['perm']]['title'];
+    }
+
+    return $this->t($this->options['perm']);
+  }
+
+
+  protected function defineOptions() {
+    $options = parent::defineOptions();
+    $options['perm'] = array('default' => 'access content');
+
+    return $options;
+  }
+
+  public function buildOptionsForm(&$form, FormStateInterface $form_state) {
+    parent::buildOptionsForm($form, $form_state);
+    // Get list of permissions
+    $perms = [];
+    $permissions = $this->permissionHandler->getPermissions();
+    foreach ($permissions as $perm => $perm_item) {
+      $provider = $perm_item['provider'];
+      $display_name = $this->moduleHandler->getName($provider);
+      $perms[$display_name][$perm] = SafeMarkup::checkPlain(strip_tags($perm_item['title']));
+    }
+
+    $form['perm'] = array(
+      '#type' => 'select',
+      '#options' => $perms,
+      '#title' => $this->t('Permission'),
+      '#default_value' => $this->options['perm'],
+      '#description' => $this->t('Only users with the selected permission flag will be able to access this display.'),
+    );
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function isCacheable() {
+    return TRUE;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function getCacheContexts() {
+    return ['user.permissions'];
+  }
+
+}

core/modules/user/src/Plugin/views/access/Role.php

@@ -0,0 +1,164 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\user\Plugin\views\access\Role.
+ */
+
+namespace Drupal\user\Plugin\views\access;
+
+use Drupal\Component\Utility\SafeMarkup;
+use Drupal\Core\Form\FormStateInterface;
+use Drupal\user\RoleStorageInterface;
+use Drupal\views\Plugin\CacheablePluginInterface;
+use Drupal\views\Plugin\views\access\AccessPluginBase;
+use Symfony\Component\DependencyInjection\ContainerInterface;
+use Symfony\Component\Routing\Route;
+use Drupal\Core\Session\AccountInterface;
+
+/**
+ * Access plugin that provides role-based access control.
+ *
+ * @ingroup views_access_plugins
+ *
+ * @ViewsAccess(
+ *   id = "role",
+ *   title = @Translation("Role"),
+ *   help = @Translation("Access will be granted to users with any of the specified roles.")
+ * )
+ */
+class Role extends AccessPluginBase implements CacheablePluginInterface {
+
+  /**
+   * Overrides Drupal\views\Plugin\Plugin::$usesOptions.
+   */
+  protected $usesOptions = TRUE;
+
+  /**
+   * The role storage.
+   *
+   * @var \Drupal\user\RoleStorageInterface
+   */
+  protected $roleStorage;
+
+  /**
+   * Constructs a Role 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\user\RoleStorageInterface $role_storage
+   *   The role storage.
+   */
+  public function __construct(array $configuration, $plugin_id, $plugin_definition, RoleStorageInterface $role_storage) {
+    parent::__construct($configuration, $plugin_id, $plugin_definition);
+    $this->roleStorage = $role_storage;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public static function create(ContainerInterface $container, array $configuration, $plugin_id, $plugin_definition) {
+    return new static(
+      $configuration,
+      $plugin_id,
+      $plugin_definition,
+      $container->get('entity.manager')->getStorage('user_role')
+    );
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function access(AccountInterface $account) {
+    return array_intersect(array_filter($this->options['role']), $account->getRoles());
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function alterRouteDefinition(Route $route) {
+    if ($this->options['role']) {
+      $route->setRequirement('_role', (string) implode('+', $this->options['role']));
+    }
+  }
+
+  public function summaryTitle() {
+    $count = count($this->options['role']);
+    if ($count < 1) {
+      return $this->t('No role(s) selected');
+    }
+    elseif ($count > 1) {
+      return $this->t('Multiple roles');
+    }
+    else {
+      $rids = user_role_names();
+      $rid = reset($this->options['role']);
+      return SafeMarkup::checkPlain($rids[$rid]);
+    }
+  }
+
+
+  protected function defineOptions() {
+    $options = parent::defineOptions();
+    $options['role'] = array('default' => array());
+
+    return $options;
+  }
+
+  public function buildOptionsForm(&$form, FormStateInterface $form_state) {
+    parent::buildOptionsForm($form, $form_state);
+    $form['role'] = array(
+      '#type' => 'checkboxes',
+      '#title' => $this->t('Role'),
+      '#default_value' => $this->options['role'],
+      '#options' => array_map('\Drupal\Component\Utility\SafeMarkup::checkPlain', user_role_names()),
+      '#description' => $this->t('Only the checked roles will be able to access this display.'),
+    );
+  }
+
+  public function validateOptionsForm(&$form, FormStateInterface $form_state) {
+    $role = $form_state->getValue(array('access_options', 'role'));
+    $role = array_filter($role);
+
+    if (!$role) {
+      $form_state->setError($form['role'], $this->t('You must select at least one role if type is "by role"'));
+    }
+
+    $form_state->setValue(array('access_options', 'role'), $role);
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function calculateDependencies() {
+    $dependencies = parent::calculateDependencies();
+
+    foreach (array_keys($this->options['role']) as $rid) {
+      if ($role = $this->roleStorage->load($rid)) {
+        $dependencies[$role->getConfigDependencyKey()][] = $role->getConfigDependencyName();
+      }
+    }
+
+    return $dependencies;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function isCacheable() {
+    return TRUE;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function getCacheContexts() {
+    return ['user.roles'];
+  }
+
+}
+

core/modules/user/src/Plugin/views/argument/RolesRid.php

@@ -0,0 +1,68 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\user\Plugin\views\argument\RolesRid.
+ */
+
+namespace Drupal\user\Plugin\views\argument;
+
+use Drupal\Component\Utility\SafeMarkup;
+use Drupal\Core\Entity\EntityManagerInterface;
+use Drupal\views\Plugin\views\argument\ManyToOne;
+use Symfony\Component\DependencyInjection\ContainerInterface;
+
+/**
+ * Allow role ID(s) as argument.
+ *
+ * @ingroup views_argument_handlers
+ *
+ * @ViewsArgument("user__roles_rid")
+ */
+class RolesRid extends ManyToOne {
+
+  /**
+   * The role entity storage
+   *
+   * @var \Drupal\user\RoleStorage
+   */
+  protected $roleStorage;
+
+  /**
+   * Constructs a \Drupal\user\Plugin\views\argument\RolesRid 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\Core\Entity\EntityManagerInterface $entity_manager
+   *   The entity manager.
+   */
+  public function __construct(array $configuration, $plugin_id, $plugin_definition, EntityManagerInterface $entity_manager) {
+    parent::__construct($configuration, $plugin_id, $plugin_definition);
+
+    $this->roleStorage = $entity_manager->getStorage('user_role');
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public static function create(ContainerInterface $container, array $configuration, $plugin_id, $plugin_definition) {
+    return parent::create($container, $configuration, $plugin_id, $plugin_definition, $container->get('entity.manager'));
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function title_query() {
+    $entities = $this->roleStorage->loadMultiple($this->value);
+    $titles = array();
+    foreach ($entities as $entity) {
+      $titles[] = SafeMarkup::checkPlain($entity->label());
+    }
+    return $titles;
+  }
+
+}

core/modules/user/src/Plugin/views/argument/Uid.php

@@ -0,0 +1,68 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\user\Plugin\views\argument\Uid.
+ */
+
+namespace Drupal\user\Plugin\views\argument;
+
+use Drupal\Component\Utility\SafeMarkup;
+use Drupal\Core\Entity\EntityStorageInterface;
+use Drupal\views\Plugin\views\argument\NumericArgument;
+use Symfony\Component\DependencyInjection\ContainerInterface;
+
+/**
+ * Argument handler to accept a user id.
+ *
+ * @ingroup views_argument_handlers
+ *
+ * @ViewsArgument("user_uid")
+ */
+class Uid extends NumericArgument {
+
+  /**
+   * The user storage.
+   *
+   * @var \Drupal\Core\Entity\EntityStorageInterface
+   */
+  protected $storage;
+
+  /**
+   * Constructs a Drupal\Component\Plugin\PluginBase 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\Core\Entity\EntityStorageInterface $storage
+   *   The user storage.
+   */
+  public function __construct(array $configuration, $plugin_id, $plugin_definition, EntityStorageInterface $storage) {
+    parent::__construct($configuration, $plugin_id, $plugin_definition);
+    $this->storage = $storage;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public static function create(ContainerInterface $container, array $configuration, $plugin_id, $plugin_definition) {
+    return new static($configuration, $plugin_id, $plugin_definition,
+      $container->get('entity.manager')->getStorage('user'));
+  }
+
+  /**
+   * Override the behavior of title(). Get the name of the user.
+   *
+   * @return array
+   *    A list of usernames.
+   */
+  public function titleQuery() {
+    return array_map(function($account) {
+      return SafeMarkup::checkPlain($account->label());
+    }, $this->storage->loadMultiple($this->value));
+  }
+
+}

core/modules/user/src/Plugin/views/argument_default/CurrentUser.php

@@ -0,0 +1,43 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\user\Plugin\views\argument_default\CurrentUser.
+ */
+
+namespace Drupal\user\Plugin\views\argument_default;
+
+use Drupal\views\Plugin\CacheablePluginInterface;
+use Drupal\views\Plugin\views\argument_default\ArgumentDefaultPluginBase;
+
+/**
+ * Default argument plugin to extract the current user
+ *
+ * This plugin actually has no options so it odes not need to do a great deal.
+ *
+ * @ViewsArgumentDefault(
+ *   id = "current_user",
+ *   title = @Translation("User ID from logged in user")
+ * )
+ */
+class CurrentUser extends ArgumentDefaultPluginBase implements CacheablePluginInterface {
+
+  public function getArgument() {
+    return \Drupal::currentUser()->id();
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function isCacheable() {
+    return TRUE;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function getCacheContexts() {
+    return ['user'];
+  }
+
+}

core/modules/user/src/Plugin/views/argument_default/User.php

@@ -0,0 +1,122 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\user\Plugin\views\argument_default\User.
+ */
+
+namespace Drupal\user\Plugin\views\argument_default;
+
+use Drupal\Core\Form\FormStateInterface;
+use Drupal\Core\Routing\RouteMatchInterface;
+use Drupal\views\Plugin\CacheablePluginInterface;
+use Drupal\views\Plugin\views\argument_default\ArgumentDefaultPluginBase;
+use Symfony\Component\DependencyInjection\ContainerInterface;
+use Symfony\Component\HttpFoundation\Request;
+use Drupal\user\UserInterface;
+use Drupal\node\NodeInterface;
+
+/**
+ * Default argument plugin to extract a user from request.
+ *
+ * @ViewsArgumentDefault(
+ *   id = "user",
+ *   title = @Translation("User ID from route context")
+ * )
+ */
+class User extends ArgumentDefaultPluginBase implements CacheablePluginInterface {
+
+  /**
+   * The route match.
+   *
+   * @var \Drupal\Core\Routing\RouteMatchInterface
+   */
+  protected $routeMatch;
+
+  /**
+   * Constructs a new User instance.
+   *
+   * @param array $configuration
+   *   A configuration array containing information about the plugin instance.
+   * @param string $plugin_id
+   *   The plugin_id for the plugin instance.
+   * @param mixed $plugin_definition
+   *   The plugin implementation definition.
+   *
+   * @param \Drupal\Core\Routing\RouteMatchInterface $route_match
+   *   The route match.
+   */
+  public function __construct(array $configuration, $plugin_id, $plugin_definition, RouteMatchInterface $route_match) {
+    parent::__construct($configuration, $plugin_id, $plugin_definition);
+
+    $this->routeMatch = $route_match;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public static function create(ContainerInterface $container, array $configuration, $plugin_id, $plugin_definition) {
+    return new static(
+      $configuration,
+      $plugin_id,
+      $plugin_definition,
+      $container->get('current_route_match')
+    );
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  protected function defineOptions() {
+    $options = parent::defineOptions();
+    $options['user'] = array('default' => '');
+
+    return $options;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function buildOptionsForm(&$form, FormStateInterface $form_state) {
+    $form['user'] = array(
+      '#type' => 'checkbox',
+      '#title' => $this->t('Also look for a node and use the node author'),
+      '#default_value' => $this->options['user'],
+    );
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function getArgument() {
+
+    // If there is a user object in the current route.
+    if ($user = $this->routeMatch->getParameter('user')) {
+      if ($user instanceof UserInterface) {
+        return $user->id();
+      }
+    }
+
+    // If option to use node author; and node in current route.
+    if (!empty($this->options['user']) && $node = $this->routeMatch->getParameter('node')) {
+      if ($node instanceof NodeInterface) {
+        return $node->getOwnerId();
+      }
+    }
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function isCacheable() {
+    return TRUE;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function getCacheContexts() {
+    return ['url'];
+  }
+
+}

core/modules/user/src/Plugin/views/argument_validator/User.php

@@ -0,0 +1,118 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\user\Plugin\views\argument_validator\User.
+ */
+
+namespace Drupal\user\Plugin\views\argument_validator;
+
+use Drupal\Core\Entity\EntityInterface;
+use Drupal\Core\Entity\EntityManagerInterface;
+use Drupal\views\Plugin\views\argument\ArgumentPluginBase;
+use Drupal\Core\Form\FormStateInterface;
+use Drupal\views\Plugin\views\argument_validator\Entity;
+
+/**
+ * Validate whether an argument is a valid user.
+ *
+ * This supports either numeric arguments (UID) or strings (username) and
+ * converts either one into the user's UID.  This validator also sets the
+ * argument's title to the username.
+ */
+class User extends Entity {
+
+  /**
+   * The user storage.
+   *
+   * @var \Drupal\Core\Entity\EntityStorageInterface
+   */
+  protected $userStorage;
+
+  /**
+   * {@inheritdoc}
+   */
+  public function __construct(array $configuration, $plugin_id, $plugin_definition, EntityManagerInterface $entity_manager) {
+    parent::__construct($configuration, $plugin_id, $plugin_definition, $entity_manager);
+
+    $this->userStorage = $entity_manager->getStorage('user');
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  protected function defineOptions() {
+    $options = parent::defineOptions();
+    $options['restrict_roles'] = array('default' => FALSE);
+    $options['roles'] = array('default' => array());
+
+    return $options;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function buildOptionsForm(&$form, FormStateInterface $form_state) {
+    parent::buildOptionsForm($form, $form_state);
+    $sanitized_id = ArgumentPluginBase::encodeValidatorId($this->definition['id']);
+
+    $form['restrict_roles'] = array(
+      '#type' => 'checkbox',
+      '#title' => $this->t('Restrict user based on role'),
+      '#default_value' => $this->options['restrict_roles'],
+    );
+
+    $form['roles'] = array(
+      '#type' => 'checkboxes',
+      '#title' => $this->t('Restrict to the selected roles'),
+      '#options' => array_map(array('\Drupal\Component\Utility\SafeMarkup', 'checkPlain'), user_role_names(TRUE)),
+      '#default_value' => $this->options['roles'],
+      '#description' => $this->t('If no roles are selected, users from any role will be allowed.'),
+      '#states' => array(
+        'visible' => array(
+          ':input[name="options[validate][options][' . $sanitized_id . '][restrict_roles]"]' => array('checked' => TRUE),
+        ),
+      ),
+    );
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function submitOptionsForm(&$form, FormStateInterface $form_state, &$options = array()) {
+    // filter trash out of the options so we don't store giant unnecessary arrays
+    $options['roles'] = array_filter($options['roles']);
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  protected function validateEntity(EntityInterface $entity) {
+    /** @var \Drupal\user\UserInterface $entity */
+    $role_check_success = TRUE;
+    // See if we're filtering users based on roles.
+    if (!empty($this->options['restrict_roles']) && !empty($this->options['roles'])) {
+      $roles = $this->options['roles'];
+      if (!(bool) array_intersect($entity->getRoles(), $roles)) {
+        $role_check_success = FALSE;
+      }
+    }
+
+    return $role_check_success && parent::validateEntity($entity);
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function calculateDependencies() {
+    $dependencies = parent::calculateDependencies();
+
+    foreach ($this->entityManager->getStorage('user_role')->loadMultiple(array_keys($this->options['roles'])) as $role) {
+      $dependencies[$role->getConfigDependencyKey()][] = $role->getConfigDependencyName();
+    }
+
+    return $dependencies;
+  }
+
+
+}

core/modules/user/src/Plugin/views/argument_validator/UserName.php

@@ -0,0 +1,85 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\user\Plugin\views\argument_validator\UserName.
+ */
+
+namespace Drupal\user\Plugin\views\argument_validator;
+
+use Drupal\Core\Form\FormStateInterface;
+
+/**
+ * Validates whether a user name is valid.
+ *
+ * @ViewsArgumentValidator(
+ *   id = "user_name",
+ *   title = @Translation("User name"),
+ *   entity_type = "user"
+ * )
+ */
+class UserName extends User {
+
+  /**
+   * {@inheritdoc}
+   */
+  public function buildOptionsForm(&$form, FormStateInterface $form_state) {
+    parent::buildOptionsForm($form, $form_state);
+
+    $entity_type = $this->entityManager->getDefinition('user');
+
+    $form['multiple']['#options'] = array(
+      0 => $this->t('Single name', array('%type' => $entity_type->getLabel())),
+      1 => $this->t('One or more names separated by , or +', array('%type' => $entity_type->getLabel())),
+    );
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function validateArgument($argument) {
+    if ($this->multipleCapable && $this->options['multiple']) {
+      // At this point only interested in individual IDs no matter what type,
+      // just splitting by the allowed delimiters.
+      $names = array_filter(preg_split('/[,+ ]/', $argument));
+    }
+    elseif ($argument) {
+      $names = array($argument);
+    }
+    // No specified argument should be invalid.
+    else {
+      return FALSE;
+    }
+
+    $accounts = $this->userStorage->loadByProperties(array('name' => $names));
+
+    // If there are no accounts, return FALSE now. As we will not enter the
+    // loop below otherwise.
+    if (empty($accounts)) {
+      return FALSE;
+    }
+
+    // Validate each account. If any fails break out and return false.
+    foreach ($accounts as $account) {
+      if (!in_array($account->getUserName(), $names) || !$this->validateEntity($account)) {
+        return FALSE;
+      }
+    }
+
+    return TRUE;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function processSummaryArguments(&$args) {
+    // If the validation says the input is an username, we should reverse the
+    // argument so it works for example for generation summary urls.
+    $uids_arg_keys = array_flip($args);
+
+    foreach ($this->userStorage->loadMultiple($args) as $uid => $account) {
+      $args[$uids_arg_keys[$uid]] = $account->label();
+    }
+  }
+
+}

core/modules/user/src/Plugin/views/field/Permissions.php

@@ -0,0 +1,132 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\user\Plugin\views\field\Permissions.
+ */
+
+namespace Drupal\user\Plugin\views\field;
+
+use Drupal\Core\Entity\EntityManagerInterface;
+use Drupal\Core\Extension\ModuleHandlerInterface;
+use Drupal\views\Plugin\views\display\DisplayPluginBase;
+use Drupal\views\ViewExecutable;
+use Drupal\views\Plugin\views\field\PrerenderList;
+use Symfony\Component\DependencyInjection\ContainerInterface;
+
+/**
+ * Field handler to provide a list of permissions.
+ *
+ * @ingroup views_field_handlers
+ *
+ * @ViewsField("user_permissions")
+ */
+class Permissions extends PrerenderList {
+
+  /**
+   * The role storage.
+   *
+   * @var \Drupal\user\RoleStorageInterface
+   */
+  protected $roleStorage;
+
+  /**
+   * The module handler.
+   *
+   * @var \Drupal\Core\Extension\ModuleHandlerInterface
+   */
+  protected $moduleHandler;
+
+  /**
+   * Constructs a Drupal\Component\Plugin\PluginBase 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\Core\Extension\ModuleHandlerInterface $module_handler
+   *   The module handler.
+   * @param \Drupal\Core\Entity\EntityManagerInterface $entity_manager
+   *   The entity manager
+   */
+  public function __construct(array $configuration, $plugin_id, $plugin_definition, ModuleHandlerInterface $module_handler, EntityManagerInterface $entity_manager) {
+    parent::__construct($configuration, $plugin_id, $plugin_definition);
+
+    $this->roleStorage = $entity_manager->getStorage('user_role');
+    $this->moduleHandler = $module_handler;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public static function create(ContainerInterface $container, array $configuration, $plugin_id, $plugin_definition) {
+    return new static($configuration, $plugin_id, $plugin_definition, $container->get('module_handler'), $container->get('entity.manager'));
+  }
+
+  /**
+   * Overrides Drupal\views\Plugin\views\field\FieldPluginBase::init().
+   */
+  public function init(ViewExecutable $view, DisplayPluginBase $display, array &$options = NULL) {
+    parent::init($view, $display, $options);
+
+    $this->additional_fields['uid'] = array('table' => 'users_field_data', 'field' => 'uid');
+  }
+
+  public function query() {
+    $this->addAdditionalFields();
+    $this->field_alias = $this->aliases['uid'];
+  }
+
+  public function preRender(&$values) {
+    $uids = array();
+    $this->items = array();
+
+    $permission_names = \Drupal::service('user.permissions')->getPermissions();
+
+    $rids = array();
+    foreach ($values as $result) {
+      $user_rids = $this->getEntity($result)->getRoles();
+      $uid = $this->getValue($result);
+
+      foreach ($user_rids as $rid) {
+        $rids[$rid][] = $uid;
+      }
+    }
+
+    if ($rids) {
+      $roles = $this->roleStorage->loadMultiple(array_keys($rids));
+      foreach ($rids as $rid => $role_uids) {
+        foreach ($roles[$rid]->getPermissions() as $permission) {
+          foreach ($role_uids as $uid) {
+            $this->items[$uid][$permission]['permission'] = $permission_names[$permission]['title'];
+          }
+        }
+      }
+
+      foreach ($uids as $uid) {
+        if (isset($this->items[$uid])) {
+          ksort($this->items[$uid]);
+        }
+      }
+    }
+  }
+
+  function render_item($count, $item) {
+    return $item['permission'];
+  }
+
+  /*
+  protected function documentSelfTokens(&$tokens) {
+    $tokens['[' . $this->options['id'] . '-role' . ']'] = $this->t('The name of the role.');
+    $tokens['[' . $this->options['id'] . '-rid' . ']'] = $this->t('The role ID of the role.');
+  }
+
+  protected function addSelfTokens(&$tokens, $item) {
+    $tokens['[' . $this->options['id'] . '-role' . ']'] = $item['role'];
+    $tokens['[' . $this->options['id'] . '-rid' . ']'] = $item['rid'];
+  }
+  */
+
+}

core/modules/user/src/Plugin/views/field/Roles.php

@@ -0,0 +1,115 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\user\Plugin\views\field\Roles.
+ */
+
+namespace Drupal\user\Plugin\views\field;
+
+use Drupal\Component\Utility\SafeMarkup;
+use Drupal\Core\Database\Connection;
+use Drupal\views\Plugin\views\display\DisplayPluginBase;
+use Drupal\views\ViewExecutable;
+use Drupal\views\Plugin\views\field\PrerenderList;
+use Symfony\Component\DependencyInjection\ContainerInterface;
+
+/**
+ * Field handler to provide a list of roles.
+ *
+ * @ingroup views_field_handlers
+ *
+ * @ViewsField("user_roles")
+ */
+class Roles extends PrerenderList {
+
+  /**
+   * Database Service Object.
+   *
+   * @var \Drupal\Core\Database\Connection
+   */
+  protected $database;
+
+  /**
+   * Constructs a Drupal\Component\Plugin\PluginBase 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\Core\Database\Connection $database
+   *   Database Service Object.
+   */
+  public function __construct(array $configuration, $plugin_id, $plugin_definition, Connection $database) {
+    parent::__construct($configuration, $plugin_id, $plugin_definition);
+
+    $this->database = $database;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public static function create(ContainerInterface $container, array $configuration, $plugin_id, $plugin_definition) {
+    return new static($configuration, $plugin_id, $plugin_definition, $container->get('database'));
+  }
+
+  /**
+   * Overrides Drupal\views\Plugin\views\field\FieldPluginBase::init().
+   */
+  public function init(ViewExecutable $view, DisplayPluginBase $display, array &$options = NULL) {
+    parent::init($view, $display, $options);
+
+    $this->additional_fields['uid'] = array('table' => 'users_field_data', 'field' => 'uid');
+  }
+
+  public function query() {
+    $this->addAdditionalFields();
+    $this->field_alias = $this->aliases['uid'];
+  }
+
+  public function preRender(&$values) {
+    $uids = array();
+    $this->items = array();
+
+    foreach ($values as $result) {
+      $uids[] = $this->getValue($result);
+    }
+
+    if ($uids) {
+      $roles = user_roles();
+      $result = $this->database->query('SELECT u.entity_id as uid, u.roles_target_id as rid FROM {user__roles} u WHERE u.entity_id IN ( :uids[] ) AND u.roles_target_id IN ( :rids[] )', array(':uids[]' => $uids, ':rids[]' => array_keys($roles)));
+      foreach ($result as $role) {
+        $this->items[$role->uid][$role->rid]['role'] = SafeMarkup::checkPlain($roles[$role->rid]->label());
+        $this->items[$role->uid][$role->rid]['rid'] = $role->rid;
+      }
+      // Sort the roles for each user by role weight.
+      $ordered_roles = array_flip(array_keys($roles));
+      foreach ($this->items as &$user_roles) {
+        // Create an array of rids that the user has in the role weight order.
+        $sorted_keys  = array_intersect_key($ordered_roles, $user_roles);
+        // Merge with the unsorted array of role information which has the
+        // effect of sorting it.
+        $user_roles = array_merge($sorted_keys, $user_roles);
+      }
+    }
+  }
+
+  function render_item($count, $item) {
+    return $item['role'];
+  }
+
+  protected function documentSelfTokens(&$tokens) {
+    $tokens['[' . $this->options['id'] . '-role' . ']'] = $this->t('The name of the role.');
+    $tokens['[' . $this->options['id'] . '-rid' . ']'] = $this->t('The role machine-name of the role.');
+  }
+
+  protected function addSelfTokens(&$tokens, $item) {
+    if (!empty($item['role'])) {
+      $tokens['[' . $this->options['id'] . '-role' . ']'] = $item['role'];
+      $tokens['[' . $this->options['id'] . '-rid' . ']'] = $item['rid'];
+    }
+  }
+
+}

core/modules/user/src/Plugin/views/field/UserBulkForm.php

@@ -0,0 +1,47 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\user\Plugin\views\field\UserBulkForm.
+ */
+
+namespace Drupal\user\Plugin\views\field;
+
+use Drupal\Core\Entity\EntityManagerInterface;
+use Drupal\Core\Form\FormStateInterface;
+use Drupal\system\Plugin\views\field\BulkForm;
+use Drupal\user\UserInterface;
+
+/**
+ * Defines a user operations bulk form element.
+ *
+ * @ViewsField("user_bulk_form")
+ */
+class UserBulkForm extends BulkForm {
+
+  /**
+   * {@inheritdoc}
+   *
+   * Provide a more useful title to improve the accessibility.
+   */
+  public function viewsForm(&$form, FormStateInterface $form_state) {
+    parent::viewsForm($form, $form_state);
+
+    if (!empty($this->view->result)) {
+      foreach ($this->view->result as $row_index => $result) {
+        $account = $result->_entity;
+        if ($account instanceof UserInterface) {
+          $form[$this->options['id']][$row_index]['#title'] = $this->t('Update the user %name', array('%name' => $account->label()));
+        }
+      }
+    }
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  protected function emptySelectedMessage() {
+    return $this->t('No users selected.');
+  }
+
+}

core/modules/user/src/Plugin/views/field/UserData.php

@@ -0,0 +1,115 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\user\Plugin\views\field\UserData.
+ */
+
+namespace Drupal\user\Plugin\views\field;
+
+use Drupal\Core\Extension\ModuleHandlerInterface;
+use Drupal\Core\Form\FormStateInterface;
+use Drupal\views\Plugin\views\display\DisplayPluginBase;
+use Drupal\views\Plugin\views\field\FieldPluginBase;
+use Drupal\views\ResultRow;
+use Drupal\views\ViewExecutable;
+use Drupal\user\UserDataInterface;
+use Symfony\Component\DependencyInjection\ContainerInterface;
+
+/**
+ * Provides access to the user data service.
+ *
+ * @ingroup views_field_handlers
+ *
+ * @see \Drupal\user\UserDataInterface
+ *
+ * @ViewsField("user_data")
+ */
+class UserData extends FieldPluginBase {
+
+  /**
+   * Provides the user data service object.
+   *
+   * @var \Drupal\user\UserDataInterface
+   */
+  protected $userData;
+
+  /**
+   * The module handler.
+   *
+   * @var \Drupal\Core\Extension\ModuleHandlerInterface
+   */
+  protected $moduleHandler;
+
+
+  /**
+   * {@inheritdoc}
+   */
+  public static function create(ContainerInterface $container, array $configuration, $plugin_id, $plugin_definition) {
+    return new static($configuration, $plugin_id, $plugin_definition, $container->get('user.data'), $container->get('module_handler'));
+  }
+
+  /**
+   * Constructs a UserData object.
+   */
+  public function __construct(array $configuration, $plugin_id, $plugin_definition, UserDataInterface $user_data, ModuleHandlerInterface $module_handler) {
+    parent::__construct($configuration, $plugin_id, $plugin_definition);
+
+    $this->userData = $user_data;
+    $this->moduleHandler = $module_handler;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  protected function defineOptions() {
+    $options = parent::defineOptions();
+
+    $options['data_module'] = array('default' => '');
+    $options['data_name'] = array('default' => '');
+
+    return $options;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function buildOptionsForm(&$form, FormStateInterface $form_state) {
+    parent::buildOptionsForm($form, $form_state);
+
+    $modules = $this->moduleHandler->getModuleList();
+    $names = array();
+    foreach (array_keys($modules) as $name) {
+      $names[$name] = $this->moduleHandler->getName($name);
+    }
+
+    $form['data_module'] = array(
+      '#title' => $this->t('Module name'),
+      '#type' => 'select',
+      '#description' => $this->t('The module which sets this user data.'),
+      '#default_value' => $this->options['data_module'],
+      '#options' => $names,
+    );
+
+    $form['data_name'] = array(
+      '#title' => $this->t('Name'),
+      '#type' => 'textfield',
+      '#description' => $this->t('The name of the data key.'),
+      '#default_value' => $this->options['data_name'],
+    );
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function render(ResultRow $values) {
+    $uid = $this->getValue($values);
+    $data = $this->userData->get($this->options['data_module'], $uid, $this->options['data_name']);
+
+    // Don't sanitize if no value was found.
+    if (isset($data)) {
+      return $this->sanitizeValue($data);
+    }
+  }
+
+}

core/modules/user/src/Plugin/views/filter/Current.php

@@ -0,0 +1,62 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\user\Plugin\views\filter\Current.
+ */
+
+namespace Drupal\user\Plugin\views\filter;
+
+use Drupal\views\Plugin\views\display\DisplayPluginBase;
+use Drupal\views\ViewExecutable;
+use Drupal\views\Plugin\views\filter\BooleanOperator;
+
+/**
+ * Filter handler for the current user.
+ *
+ * @ingroup views_filter_handlers
+ *
+ * @ViewsFilter("user_current")
+ */
+class Current extends BooleanOperator {
+
+  /**
+   * Overrides Drupal\views\Plugin\views\filter\BooleanOperator::init().
+   */
+  public function init(ViewExecutable $view, DisplayPluginBase $display, array &$options = NULL) {
+    parent::init($view, $display, $options);
+
+    $this->value_value = $this->t('Is the logged in user');
+  }
+
+  public function query() {
+    $this->ensureMyTable();
+
+    $field = $this->tableAlias . '.' . $this->realField . ' ';
+    $or = db_or();
+
+    if (empty($this->value)) {
+      $or->condition($field, '***CURRENT_USER***', '<>');
+      if ($this->accept_null) {
+        $or->isNull($field);
+      }
+    }
+    else {
+      $or->condition($field, '***CURRENT_USER***', '=');
+    }
+    $this->query->addWhere($this->options['group'], $or);
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function getCacheContexts() {
+    $contexts = parent::getCacheContexts();
+
+    // This filter depends on the current user.
+    $contexts[] = 'user';
+
+    return $contexts;
+  }
+
+}

core/modules/user/src/Plugin/views/filter/Name.php

@@ -0,0 +1,127 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\user\Plugin\views\filter\Name.
+ */
+
+namespace Drupal\user\Plugin\views\filter;
+
+use Drupal\Component\Utility\Tags;
+use Drupal\Core\Entity\Element\EntityAutocomplete;
+use Drupal\Core\Form\FormStateInterface;
+use Drupal\user\Entity\User;
+use Drupal\views\Plugin\views\filter\InOperator;
+
+/**
+ * Filter handler for usernames.
+ *
+ * @ingroup views_filter_handlers
+ *
+ * @ViewsFilter("user_name")
+ */
+class Name extends InOperator {
+
+  protected $alwaysMultiple = TRUE;
+
+  protected function valueForm(&$form, FormStateInterface $form_state) {
+    $users = $this->value ? User::loadMultiple($this->value) : array();
+    $default_value = EntityAutocomplete::getEntityLabels($users);
+    $form['value'] = array(
+      '#type' => 'entity_autocomplete',
+      '#title' => $this->t('Usernames'),
+      '#description' => $this->t('Enter a comma separated list of user names.'),
+      '#target_type' => 'user',
+      '#tags' => TRUE,
+      '#default_value' => $default_value,
+      '#process_default_value' => FALSE,
+    );
+
+    $user_input = $form_state->getUserInput();
+    if ($form_state->get('exposed') && !isset($user_input[$this->options['expose']['identifier']])) {
+      $user_input[$this->options['expose']['identifier']] = $default_value;
+      $form_state->setUserInput($user_input);
+    }
+  }
+
+  protected function valueValidate($form, FormStateInterface $form_state) {
+    $uids = [];
+    if ($values = $form_state->getValue(array('options', 'value'))) {
+      foreach ($values as $value) {
+        $uids[] = $value['target_id'];
+      }
+      sort($uids);
+    }
+    $form_state->setValue(array('options', 'value'), $uids);
+  }
+
+  public function acceptExposedInput($input) {
+    $rc = parent::acceptExposedInput($input);
+
+    if ($rc) {
+      // If we have previously validated input, override.
+      if (isset($this->validated_exposed_input)) {
+        $this->value = $this->validated_exposed_input;
+      }
+    }
+
+    return $rc;
+  }
+
+  public function validateExposed(&$form, FormStateInterface $form_state) {
+    if (empty($this->options['exposed'])) {
+      return;
+    }
+
+    if (empty($this->options['expose']['identifier'])) {
+      return;
+    }
+
+    $identifier = $this->options['expose']['identifier'];
+    $input = $form_state->getValue($identifier);
+
+    if ($this->options['is_grouped'] && isset($this->options['group_info']['group_items'][$input])) {
+      $this->operator = $this->options['group_info']['group_items'][$input]['operator'];
+      $input = $this->options['group_info']['group_items'][$input]['value'];
+    }
+
+    $uids = [];
+    $values = $form_state->getValue($identifier);
+    if ($values && (!$this->options['is_grouped'] || ($this->options['is_grouped'] && ($input != 'All')))) {
+      foreach ($values as $value) {
+        $uids[] = $value['target_id'];
+      }
+    }
+
+    if ($uids) {
+      $this->validated_exposed_input = $uids;
+    }
+  }
+
+  protected function valueSubmit($form, FormStateInterface $form_state) {
+    // prevent array filter from removing our anonymous user.
+  }
+
+  // Override to do nothing.
+  public function getValueOptions() { }
+
+  public function adminSummary() {
+    // set up $this->valueOptions for the parent summary
+    $this->valueOptions = array();
+
+    if ($this->value) {
+      $result = entity_load_multiple_by_properties('user', array('uid' => $this->value));
+      foreach ($result as $account) {
+        if ($account->id()) {
+          $this->valueOptions[$account->id()] = $account->label();
+        }
+        else {
+          $this->valueOptions[$account->id()] = 'Anonymous'; // Intentionally NOT translated.
+        }
+      }
+    }
+
+    return parent::adminSummary();
+  }
+
+}

core/modules/user/src/Plugin/views/filter/Permissions.php

@@ -0,0 +1,108 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\user\Plugin\views\filter\Permissions.
+ */
+
+namespace Drupal\user\Plugin\views\filter;
+
+use Drupal\Component\Utility\SafeMarkup;
+use Drupal\Core\Extension\ModuleHandlerInterface;
+use Drupal\user\PermissionHandlerInterface;
+use Drupal\views\Plugin\views\filter\ManyToOne;
+use Symfony\Component\DependencyInjection\ContainerInterface;
+
+/**
+ * Filter handler for user roles.
+ *
+ * @ingroup views_filter_handlers
+ *
+ * @ViewsFilter("user_permissions")
+ */
+class Permissions extends ManyToOne {
+
+  /**
+   * The permission handler.
+   *
+   * @var \Drupal\user\PermissionHandlerInterface
+   */
+  protected $permissionHandler;
+
+  /**
+   * The module handler.
+   *
+   * @var \Drupal\Core\Extension\ModuleHandlerInterface
+   */
+  protected $moduleHandler;
+
+  /**
+   * Constructs a Permissions 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\user\PermissionHandlerInterface $permission_handler
+   *   The permission handler.
+   * @param \Drupal\Core\Extension\ModuleHandlerInterface $module_handler
+   *   The module handler.
+   */
+  public function __construct(array $configuration, $plugin_id, $plugin_definition, PermissionHandlerInterface $permission_handler, ModuleHandlerInterface $module_handler) {
+    parent::__construct($configuration, $plugin_id, $plugin_definition);
+
+    $this->permissionHandler = $permission_handler;
+    $this->moduleHandler = $module_handler;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public static function create(ContainerInterface $container, array $configuration, $plugin_id, $plugin_definition) {
+    return new static(
+      $configuration,
+      $plugin_id,
+      $plugin_definition,
+      $container->get('user.permissions'),
+      $container->get('module_handler')
+    );
+  }
+
+  public function getValueOptions() {
+    if (!isset($this->valueOptions)) {
+      $permissions = $this->permissionHandler->getPermissions();
+      foreach ($permissions as $perm => $perm_item) {
+        $provider = $perm_item['provider'];
+        $display_name = $this->moduleHandler->getName($provider);
+        $this->valueOptions[$display_name][$perm] = SafeMarkup::checkPlain(strip_tags($perm_item['title']));
+      }
+    }
+    else {
+      return $this->valueOptions;
+    }
+  }
+
+  /**
+   * {@inheritdoc}
+   *
+   * Replace the configured permission with a filter by all roles that have this
+   * permission.
+   */
+  public function query() {
+    // @todo user_role_names() should maybe support multiple permissions.
+    $rids = array();
+    // Get all roles, that have the configured permissions.
+    foreach ($this->value as $permission) {
+      $roles = user_role_names(FALSE, $permission);
+      $rids += array_keys($roles);
+    }
+    $rids = array_unique($rids);
+    $this->value = $rids;
+
+    // $this->value contains the role IDs that have the configured permission.
+    parent::query();
+  }
+
+}

core/modules/user/src/Plugin/views/filter/Roles.php

@@ -0,0 +1,87 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\user\Plugin\views\filter\Roles.
+ */
+
+namespace Drupal\user\Plugin\views\filter;
+
+use Drupal\user\RoleInterface;
+use Drupal\user\RoleStorageInterface;
+use Drupal\views\Plugin\views\filter\ManyToOne;
+use Symfony\Component\DependencyInjection\ContainerInterface;
+
+/**
+ * Filter handler for user roles.
+ *
+ * @ingroup views_filter_handlers
+ *
+ * @ViewsFilter("user_roles")
+ */
+class Roles extends ManyToOne {
+
+  /**
+   * The role storage.
+   *
+   * @var \Drupal\user\RoleStorageInterface
+   */
+  protected $roleStorage;
+
+  /**
+   * Constructs a Roles 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\user\RoleStorageInterface $role_storage
+   *   The role storage.
+   */
+  public function __construct(array $configuration, $plugin_id, $plugin_definition, RoleStorageInterface $role_storage) {
+    parent::__construct($configuration, $plugin_id, $plugin_definition);
+    $this->roleStorage = $role_storage;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public static function create(ContainerInterface $container, array $configuration, $plugin_id, $plugin_definition) {
+    return new static(
+      $configuration,
+      $plugin_id,
+      $plugin_definition,
+      $container->get('entity.manager')->getStorage('user_role')
+    );
+  }
+
+  public function getValueOptions() {
+    $this->valueOptions = user_role_names(TRUE);
+    unset($this->valueOptions[RoleInterface::AUTHENTICATED_ID]);
+  }
+
+  /**
+   * Override empty and not empty operator labels to be clearer for user roles.
+   */
+  function operators() {
+    $operators = parent::operators();
+    $operators['empty']['title'] = $this->t("Only has the 'authenticated user' role");
+    $operators['not empty']['title'] = $this->t("Has roles in addition to 'authenticated user'");
+    return $operators;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function calculateDependencies() {
+    $dependencies = array();
+    foreach ($this->value as $role_id) {
+      $role = $this->roleStorage->load($role_id);
+      $dependencies[$role->getConfigDependencyKey()][] = $role->getConfigDependencyName();
+    }
+    return $dependencies;
+  }
+
+}

core/modules/user/src/Plugin/views/row/UserRow.php

@@ -0,0 +1,33 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\user\Plugin\views\row\UserRow.
+ */
+
+namespace Drupal\user\Plugin\views\row;
+
+use Drupal\views\Plugin\views\row\EntityRow;
+
+/**
+ * A row plugin which renders a user.
+ *
+ * @ingroup views_row_plugins
+ *
+ * @ViewsRow(
+ *   id = "entity:user",
+ * )
+ */
+class UserRow extends EntityRow {
+
+  /**
+   * {@inheritdoc}
+   */
+  protected function defineOptions() {
+    $options = parent::defineOptions();
+    $options['view_mode']['default'] = 'full';
+
+    return $options;
+  }
+
+}

core/modules/user/src/Plugin/views/wizard/Users.php

@@ -0,0 +1,81 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\user\Plugin\views\wizard\Users.
+ */
+
+namespace Drupal\user\Plugin\views\wizard;
+
+use Drupal\views\Plugin\views\wizard\WizardPluginBase;
+
+/**
+ * @todo: replace numbers with constants.
+ */
+
+/**
+ * Tests creating user views with the wizard.
+ *
+ * @ViewsWizard(
+ *   id = "users",
+ *   base_table = "users_field_data",
+ *   title = @Translation("Users")
+ * )
+ */
+class Users extends WizardPluginBase {
+
+  /**
+   * Set the created column.
+   */
+  protected $createdColumn = 'created';
+
+  /**
+   * Set default values for the filters.
+   */
+  protected $filters = array(
+    'status' => array(
+      'value' => TRUE,
+      'table' => 'users_field_data',
+      'field' => 'status',
+      'plugin_id' => 'boolean',
+      'entity_type' => 'user',
+      'entity_field' => 'status',
+    )
+  );
+
+  /**
+   * Overrides Drupal\views\Plugin\views\wizard\WizardPluginBase::defaultDisplayOptions().
+   */
+  protected function defaultDisplayOptions() {
+    $display_options = parent::defaultDisplayOptions();
+
+    // Add permission-based access control.
+    $display_options['access']['type'] = 'perm';
+    $display_options['access']['options']['perm'] = 'access user profiles';
+
+    // Remove the default fields, since we are customizing them here.
+    unset($display_options['fields']);
+
+    /* Field: User: Name */
+    $display_options['fields']['name']['id'] = 'name';
+    $display_options['fields']['name']['table'] = 'users_field_data';
+    $display_options['fields']['name']['field'] = 'name';
+    $display_options['fields']['name']['entity_type'] = 'user';
+    $display_options['fields']['name']['entity_field'] = 'name';
+    $display_options['fields']['name']['label'] = '';
+    $display_options['fields']['name']['alter']['alter_text'] = 0;
+    $display_options['fields']['name']['alter']['make_link'] = 0;
+    $display_options['fields']['name']['alter']['absolute'] = 0;
+    $display_options['fields']['name']['alter']['trim'] = 0;
+    $display_options['fields']['name']['alter']['word_boundary'] = 0;
+    $display_options['fields']['name']['alter']['ellipsis'] = 0;
+    $display_options['fields']['name']['alter']['strip_tags'] = 0;
+    $display_options['fields']['name']['alter']['html'] = 0;
+    $display_options['fields']['name']['hide_empty'] = 0;
+    $display_options['fields']['name']['empty_zero'] = 0;
+    $display_options['fields']['name']['plugin_id'] = 'field';
+
+    return $display_options;
+  }
+
+}