Move into nested docroot

web/core/modules/help/src/Plugin/Block/HelpBlock.php

@@ -0,0 +1,115 @@
+<?php
+
+namespace Drupal\help\Plugin\Block;
+
+use Drupal\Core\Block\BlockBase;
+use Drupal\Core\Cache\Cache;
+use Drupal\Core\Extension\ModuleHandlerInterface;
+use Drupal\Core\Plugin\ContainerFactoryPluginInterface;
+use Drupal\Core\Routing\RouteMatchInterface;
+use Symfony\Component\DependencyInjection\ContainerInterface;
+use Symfony\Component\HttpFoundation\Request;
+
+/**
+ * Provides a 'Help' block.
+ *
+ * @Block(
+ *   id = "help_block",
+ *   admin_label = @Translation("Help")
+ * )
+ */
+class HelpBlock extends BlockBase implements ContainerFactoryPluginInterface {
+
+  /**
+   * The module handler.
+   *
+   * @var \Drupal\Core\Extension\ModuleHandlerInterface
+   */
+  protected $moduleHandler;
+
+  /**
+   * The current request.
+   *
+   * @var \Symfony\Component\HttpFoundation\Request
+   */
+  protected $request;
+
+  /**
+   * The current route match.
+   *
+   * @var \Drupal\Core\Routing\RouteMatchInterface
+   */
+  protected $routeMatch;
+
+  /**
+   * Creates a HelpBlock 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 \Symfony\Component\HttpFoundation\Request $request
+   *   The current request.
+   * @param \Drupal\Core\Extension\ModuleHandlerInterface $module_handler
+   *   The module handler.
+   * @param \Drupal\Core\Routing\RouteMatchInterface $route_match
+   *   The current route match.
+   */
+  public function __construct(array $configuration, $plugin_id, $plugin_definition, Request $request, ModuleHandlerInterface $module_handler, RouteMatchInterface $route_match) {
+    parent::__construct($configuration, $plugin_id, $plugin_definition);
+
+    $this->request = $request;
+    $this->moduleHandler = $module_handler;
+    $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('request_stack')->getCurrentRequest(),
+      $container->get('module_handler'),
+      $container->get('current_route_match')
+    );
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function build() {
+    // Do not show on a 403 or 404 page.
+    if ($this->request->attributes->has('exception')) {
+      return [];
+    }
+
+    $implementations = $this->moduleHandler->getImplementations('help');
+    $build = [];
+    $args = [
+      $this->routeMatch->getRouteName(),
+      $this->routeMatch,
+    ];
+    foreach ($implementations as $module) {
+      // Don't add empty strings to $build array.
+      if ($help = $this->moduleHandler->invoke($module, 'help', $args)) {
+        // Convert strings to #markup render arrays so that they will XSS admin
+        // filtered.
+        $build[] = is_array($help) ? $help : ['#markup' => $help];
+      }
+    }
+    return $build;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function getCacheContexts() {
+    return Cache::mergeContexts(parent::getCacheContexts(), ['route']);
+  }
+
+}

web/core/modules/help/src/Plugin/HelpSection/HelpSectionPluginBase.php

@@ -0,0 +1,34 @@
+<?php
+
+namespace Drupal\help\Plugin\HelpSection;
+
+use Drupal\Core\Cache\UnchangingCacheableDependencyTrait;
+use Drupal\Core\Plugin\PluginBase;
+use Drupal\help\HelpSectionPluginInterface;
+
+/**
+ * Provides a base class for help section plugins.
+ *
+ * @see \Drupal\help\HelpSectionPluginInterface
+ * @see \Drupal\help\Annotation\HelpSection
+ * @see \Drupal\help\HelpSectionManager
+ */
+abstract class HelpSectionPluginBase extends PluginBase implements HelpSectionPluginInterface {
+
+  use UnchangingCacheableDependencyTrait;
+
+  /**
+   * {@inheritdoc}
+   */
+  public function getTitle() {
+    return $this->getPluginDefinition()['title'];
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function getDescription() {
+    return $this->getPluginDefinition()['description'];
+  }
+
+}

web/core/modules/help/src/Plugin/HelpSection/HookHelpSection.php

@@ -0,0 +1,72 @@
+<?php
+
+namespace Drupal\help\Plugin\HelpSection;
+
+use Drupal\Core\Extension\ModuleHandlerInterface;
+use Drupal\Core\Link;
+use Drupal\Core\Plugin\ContainerFactoryPluginInterface;
+use Symfony\Component\DependencyInjection\ContainerInterface;
+
+/**
+ * Provides the module topics list section for the help page.
+ *
+ * @HelpSection(
+ *   id = "hook_help",
+ *   title = @Translation("Module overviews"),
+ *   description = @Translation("Module overviews are provided by modules. Overviews available for your installed modules:"),
+ * )
+ */
+class HookHelpSection extends HelpSectionPluginBase implements ContainerFactoryPluginInterface {
+
+  /**
+   * The module handler.
+   *
+   * @var \Drupal\Core\Extension\ModuleHandlerInterface
+   */
+  protected $moduleHandler;
+
+  /**
+   * Constructs a HookHelpSection 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 service.
+   */
+  public function __construct(array $configuration, $plugin_id, $plugin_definition, ModuleHandlerInterface $module_handler) {
+    parent::__construct($configuration, $plugin_id, $plugin_definition);
+    $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')
+    );
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function listTopics() {
+    $topics = [];
+    foreach ($this->moduleHandler->getImplementations('help') as $module) {
+      $title = $this->moduleHandler->getName($module);
+      $topics[$title] = Link::createFromRoute($title, 'help.page', ['name' => $module]);
+    }
+
+    // Sort topics by title, which is the array key above.
+    ksort($topics);
+    return $topics;
+  }
+
+}