MemoryBackendTest.php

<?php

namespace Drupal\KernelTests\Core\Cache;

use Drupal\Core\Cache\MemoryBackend;

/**
 * Unit test of the memory cache backend using the generic cache unit test base.
 *
 * @group Cache
 */
class MemoryBackendTest extends GenericCacheBackendUnitTestBase {
    
    /**
     * Creates a new instance of MemoryBackend.
     *
     * @return \Drupal\Core\Cache\CacheBackendInterface
     *   A new MemoryBackend object.
     */
    protected function createCacheBackend($bin) {
        $backend = new MemoryBackend();
        \Drupal::service('cache_tags.invalidator')->addInvalidator($backend);
        return $backend;
    }

}