/**
* @param CartInterface $quote
* @param AddressInterface $address
* @param string $method
* @return CartInterface
*/
private function prepareShippingAssignment(CartInterface $quote, AddressInterface $address, $method)
{
$cartExtension = $quote->getExtensionAttributes();
if ($cartExtension === null) {
$cartExtension = $this->getCartExtensionFactory()->create();
}
$shippingAssignment = $cartExtension->getShippingAssignments()[0];
if ($cartExtension->getShippingAssignments() === null) {
$shippingAssignment = $this->getShippingAssignmentFactory()->create();
}
$shipping = $shippingAssignment->getShipping();
if ($shipping === null) {
$shipping = $this->getShippingFactory()->create();
}
$shipping->setAddress($address);
$shipping->setMethod($method);
$shippingAssignment->setShipping($shipping);
$cartExtension->setShippingAssignments([$shippingAssignment]);
return $quote->setExtensionAttributes($cartExtension);
}