Bug 220561

Calling event.updateWith inside the onshippingaddresschange or onshippingoptionchange event handlers with a PaymentDetailsUpdate object requires “total” to be included. When “total” is not included an error “RangeError: "" is not a valid currency code." is thrown. 

I expect “total” to NOT be required in the PaymentDetailsUpdate. Note: “total” should be required for PaymentDetailsInit but not for PaymentDetailsUpdate. Note: “newTotal” is required in the ApplePayJS API when using ApplePayShippingContactUpdate.

Simple example:

request.onshippingaddresschange = event => {
    const paymentDetailsUpdate = {};
    event.updateWith(paymentDetailsUpdate);
};

The above example will throw an error.

Though the PaymentDetailsUpdate can be more complex. 
For example, I might want to include an error in the PaymentDetailsUpdate:

const paymentDetailsUpdate = {
    "error": "Can't ship to this address."
}

This won’t work unless I include the total as such:

const paymentDetailsUpdate = {
    "total": {
        "label": "My Merchant",
        "amount": {
            "value": "27.50",
            "currency": "USD"
        }
    },
    "error": "Can't ship to this address."
}