createCacheBackend example

/** * Gets a backend to test; this will get a shared instance set in the object. * * @return \Drupal\Core\Cache\CacheBackendInterface * Cache backend to test. */
  protected function getCacheBackend($bin = NULL) {
    if (!isset($bin)) {
      $bin = $this->getTestBin();
    }
    if (!isset($this->cachebackends[$bin])) {
      $this->cachebackends[$bin] = $this->createCacheBackend($bin);
      // Ensure the backend is empty.       $this->cachebackends[$bin]->deleteAll();
    }
    return $this->cachebackends[$bin];
  }

  /** * {@inheritdoc} */
  protected function setUp(): void {
    $this->cachebackends = [];