public function testCredentials()
{
$credentials = new Credentials(self::MERCHANT, self::PRIVATE_KEY, new Md5Algorithm(), self::ENCRYPTION_PROTOCOL);
$this->assertEquals(self::MERCHANT, $credentials->getMerchantPosId());
$this->assertEquals(self::PRIVATE_KEY, $credentials->getPrivateKey());
$this->assertEquals(self::ENCRYPTION_PROTOCOL, $credentials->getEncryptionProtocols());
$this->assertInstanceOf('\\Team3\\PayU\\SignatureCalculator\\Encoder\\Algorithms\\AlgorithmInterface', $credentials->getSignatureAlgorithm());
}