Issue #3314143: Add documentation for testing minor updates

src/Form/UpdaterForm.php

@@ -4,6 +4,8 @@ namespace Drupal\automatic_updates\Form;
 
 use Drupal\automatic_updates\BatchProcessor;
 use Drupal\automatic_updates\Event\ReadinessCheckEvent;
+use Drupal\Core\Extension\ModuleHandlerInterface;
+use Drupal\Core\Link;
 use Drupal\package_manager\FailureMarker;
 use Drupal\package_manager\ProjectInfo;
 use Drupal\automatic_updates\ReleaseChooser;
@@ -82,6 +84,13 @@ final class UpdaterForm extends FormBase {
    */
   protected $failureMarker;
 
+  /**
+   * The module handler service.
+   *
+   * @var \Drupal\Core\Extension\ModuleHandlerInterface
+   */
+  protected $moduleHandler;
+
   /**
    * Constructs a new UpdaterForm object.
    *
@@ -97,14 +106,17 @@ final class UpdaterForm extends FormBase {
    *   The renderer service.
    * @param \Drupal\package_manager\FailureMarker $failure_marker
    *   The failure marker service.
+   * @param \Drupal\Core\Extension\ModuleHandlerInterface $module_handler
+   *   The module handler service.
    */
-  public function __construct(StateInterface $state, Updater $updater, EventDispatcherInterface $event_dispatcher, ReleaseChooser $release_chooser, RendererInterface $renderer, FailureMarker $failure_marker) {
+  public function __construct(StateInterface $state, Updater $updater, EventDispatcherInterface $event_dispatcher, ReleaseChooser $release_chooser, RendererInterface $renderer, FailureMarker $failure_marker, ModuleHandlerInterface $module_handler) {
     $this->updater = $updater;
     $this->state = $state;
     $this->eventDispatcher = $event_dispatcher;
     $this->releaseChooser = $release_chooser;
     $this->renderer = $renderer;
     $this->failureMarker = $failure_marker;
+    $this->moduleHandler = $module_handler;
   }
 
   /**
@@ -124,7 +136,8 @@ final class UpdaterForm extends FormBase {
       $container->get('event_dispatcher'),
       $container->get('automatic_updates.release_chooser'),
       $container->get('renderer'),
-      $container->get('package_manager.failure_marker')
+      $container->get('package_manager.failure_marker'),
+      $container->get('module_handler')
     );
   }
 
@@ -296,6 +309,13 @@ final class UpdaterForm extends FormBase {
         $create_update_buttons,
         $is_primary
       );
+      if ($this->moduleHandler->moduleExists('help')) {
+        $url = Url::fromRoute('help.page')
+          ->setRouteParameter('name', 'automatic_updates')
+          ->setOption('fragment', 'minor-update');
+        $text = $this->t('Learn more about updating to another minor version of Drupal.');
+        $form['next_minor']['#suffix'] .= Link::fromTextAndUrl($text, $url)->toString();
+      }
     }
 
     $form['backup'] = [