yii2-swiftmailer/tests/unit/framework/caching/ZendDataCacheTest.php

<?php
namespace yiiunit\framework\caching;

use yii\caching\Cache;
use yii\caching\ZendDataCache;

/**
 * Class for testing Zend cache backend
 */
class ZendDataCacheTest extends CacheTestCase
{
	private $_cacheInstance = null;

	/**
	 * @return ZendDataCache
	 */
	protected function getCacheInstance()
	{
		if (!function_exists("zend_shm_cache_store")) {
			$this->markTestSkipped("Zend Data cache not installed. Skipping.");
		}

		if ($this->_cacheInstance === null) {
			$this->_cacheInstance = new ZendDataCache();
		}
		return $this->_cacheInstance;
	}
}