public function save(UnitTester $I)
{
$I->wantTo('Save data by using Memory as cache backend');
$key = 'data-save';
$data = [uniqid(), gethostname(), microtime(), get_include_path(), time()];
$cache = new Memory(new Data(['lifetime' => 20]));
$I->assertNull($cache->get($key));
$I->assertTrue($cache->save($key, $data));
$I->assertEquals($data, $cache->get($key));
$I->assertEquals([$key => serialize($data)], $I->getProtectedProperty($cache, '_data'));
$I->assertTrue($cache->save($key, 2017));
$I->assertEquals(2017, $cache->get($key));
$I->assertEquals([$key => 2017], $I->getProtectedProperty($cache, '_data'));
}