public function testWriteNoExpiry()
{
$key = 'default_key';
$data = 'value';
$keys = array($key => $data);
$redis = new Redis(array('expiry' => null));
$expiry = null;
$result = $redis->write($keys, $expiry);
$this->assertTrue($result);
$result = $this->_redis->exists($key);
$this->assertTrue($result);
$expected = -1;
$result = $this->_redis->ttl($key);
$this->assertEqual($expected, $result);
$this->_redis->delete($key);
$redis = new Redis(array('expiry' => Cache::PERSIST));
$expiry = Cache::PERSIST;
$result = $redis->write($keys, $expiry);
$this->assertTrue($result);
$result = $this->_redis->exists($key);
$this->assertTrue($result);
$expected = -1;
$result = $this->_redis->ttl($key);
$this->assertEqual($expected, $result);
$this->_redis->delete($key);
$redis = new Redis();
$expiry = Cache::PERSIST;
$result = $redis->write($keys, $expiry);
$this->assertTrue($result);
$result = $this->_redis->exists($key);
$this->assertTrue($result);
$expected = -1;
$result = $this->_redis->ttl($key);
$this->assertEqual($expected, $result);
$this->_redis->delete($key);
}