Adding a test, and a test module, to show that bundles provided by modules...

Adding a test, and a test module, to show that bundles provided by modules have their services added to the DIC

core/modules/system/lib/Drupal/system/Tests/Bundle/BundleTest.php

+<?php
+
+/**
+ * @file
+ * Definition of Drupal\system\Tests\Bundle\BundleTest.
+ */
+
+namespace Drupal\system\Tests\Bundle;
+
+use Drupal\simpletest\WebTestBase;
+
+/**
+ * Test bundle registration to the DIC.
+ */
+class BundleTest extends WebTestBase {
+  public static function getInfo() {
+    return array(
+      'name' => 'Bundle Registration',
+      'description' => 'Tests bundle registration to the DIC.',
+      'group' => 'Bundle',
+    );
+  }
+
+  function setUp() {
+    parent::setUp('bundle_test');
+  }
+
+  /**
+   * Test that services provided by module bundles get registered to the DIC.
+   */
+  function testBundleRegistration() {
+    $this->drupalGet('bundle_test');
+    $this->assertText(t('The service with id bundle_test_class is available in the DIC'), t('The bundle_test_class service has been registered to the DIC'));
+    $this->drupalGet('');
+    $this->assertText(t('The bundle_test event subscriber fired!'), t('The bundle_test event subscriber fired'));
+  }
+}

core/modules/system/tests/modules/bundle_test/bundle_test.info

+name = "Bundle test"
+description = "Support module for bundle testing."
+package = Testing
+version = VERSION
+core = 8.x
+hidden = TRUE

core/modules/system/tests/modules/bundle_test/bundle_test.module

+<?php
+
+/**
+ * Implements hook_menu().
+ */
+function bundle_test_menu() {
+  $items['bundle_test'] = array(
+    'type' => MENU_CALLBACK,
+    'title' => t('Bundle test callback'),
+    'page callback' => 'bundle_test_callback',
+    'access callback' => TRUE,
+  );
+  return $items;
+}
+
+/**
+ * Simple callback for testing that the bundle_test_class service exists in the
+ * DIC.
+ */
+function bundle_test_callback() {
+  if (drupal_container()->has('bundle_test_class')) {
+    return t('The service with id bundle_test_class is available in the DIC');
+  }
+  return t('Service not found');
+}
+

core/modules/system/tests/modules/bundle_test/lib/Drupal/bundle_test/BundleTestBundle.php

+<?php
+
+namespace Drupal\bundle_test;
+
+use Symfony\Component\DependencyInjection\Definition;
+use Symfony\Component\DependencyInjection\ContainerBuilder;
+use Symfony\Component\DependencyInjection\Reference;
+use Symfony\Component\HttpKernel\Bundle\Bundle;
+
+/**
+ * Test bundle class.
+ */
+class BundleTestBundle extends Bundle
+{
+  public function build(ContainerBuilder $container) {
+    $container->register('bundle_test_class', 'Drupal\bundle_test\TestClass')
+      ->addTag('kernel.event_subscriber');
+  }
+}
\ No newline at end of file

core/modules/system/tests/modules/bundle_test/lib/Drupal/bundle_test/TestClass.php

+<?php
+
+namespace Drupal\bundle_test;
+
+use Symfony\Component\HttpKernel\KernelEvents;
+use Symfony\Component\HttpKernel\Event\GetResponseEvent;
+use Symfony\Component\EventDispatcher\EventSubscriberInterface;
+
+class TestClass implements EventSubscriberInterface {
+
+  /**
+   * A simple kernel listener method.
+   */
+  public function onKernelRequestTest(GetResponseEvent $event) {
+    drupal_set_message(t('The bundle_test event subscriber fired!'));
+  }
+
+  /**
+   * Registers methods as kernel listeners.
+   *
+   * @return array
+   *   An array of event listener definitions.
+   */
+  static function getSubscribedEvents() {
+    $events[KernelEvents::REQUEST][] = array('onKernelRequestTest', 100);
+    return $events;
+  }
+}
\ No newline at end of file