--- /dev/null
+<?php
+
+namespace Drupal\Tests\{{ machine_name }}\Kernel;
+
+use Drupal\block\Entity\Block;
+use Drupal\KernelTests\KernelTestBase;
+
+/**
+ * Test description.
+ *
+ * @group {{ machine_name }}
+ */
+class {{ class }} extends KernelTestBase {
+
+ /**
+ * {@inheritdoc}
+ */
+ public static $modules = ['block', 'system', 'user'];
+
+ /**
+ * {@inheritdoc}
+ */
+ protected function setUp() {
+ parent::setUp();
+ $this->container
+ ->get('entity_type.manager')
+ ->getStorage('block')
+ ->create([
+ 'id' => 'test_block',
+ 'theme' => 'stark',
+ 'plugin' => 'system_powered_by_block',
+ ])
+ ->save();
+ }
+
+ /**
+ * Test callback.
+ */
+ public function testBlockRendering() {
+ $entity = Block::load('test_block');
+
+ $build = \Drupal::entityTypeManager()
+ ->getViewBuilder($entity->getEntityTypeId())
+ ->view($entity);
+
+ $content = $this
+ ->container
+ ->get('renderer')
+ ->renderRoot($build);
+
+ $this->assertTrue(
+ strpos(strip_tags($content), 'Powered by Drupal') !== FALSE,
+ 'Valid block content was found.'
+ );
+ }
+
+}