ApaiIO\Operations\CartAdd::setHMAC PHP Method

    public function setHMAC($HMAC)
    {
        $this->parameters['HMAC'] = $HMAC;
    }

 public function testGetHMAC()
 {
     $cart = new CartAdd();
     $this->assertEquals(null, $cart->getHMAC());
     $cart->setHMAC('1234');
     $this->assertEquals('1234', $cart->getHMAC());
 }