Create new Guest Cart when Checkout resets

[supernova-at]

Description

This PR creates a new guest cart whenever the checkout/reset action is triggered.

The Continue Shopping button triggers this action and thus creates a new guest cart on click. The user can add items to the newly created cart without error.

Alternative Solutions

Move the Dispatch

The following code appears when trying to add an item to the cart:

        } catch (error) {
            const { response, noGuestCartId } = error;

            dispatch(actions.addItem.receive(error));

            // check if the guest cart has expired
            if (noGuestCartId || (response && response.status === 404)) {
                // if so, then delete the cached ID...
                // in contrast to the save, make sure storage deletion is
                // complete before dispatching the error--you don't want an
                // upstream action to try and reuse the known-bad ID.
                await clearGuestCartId();
                // then create a new one
                await dispatch(createGuestCart());
                // then retry this operation
                return thunk(...arguments);
            }
        }

We could move the dispatch(actions.addItem.receive(error)); line to after the "no guest cart" retry logic so that the error only gets dispatched when there is truly an unhandled error.

This "no guest cart" retry logic does appear in many places, however, so we'd likely want to make this change app-wide (in all the asyncActions.js files).

Handle the Error in the Reducer

This has the effect of signaling the backstop error catching reducer that we're handling the error (by retrying) and that it shouldn't pop up a notification.

Related Issue

Closes #916 .

Motivation and Context

This change allows users to add items to their cart after a successful purchase.

How Has This Been Tested?

See the repro steps in #916.

Screenshots (if appropriate):

Proposed Labels for Change Type/Package

BUG

venia-concept

Checklist:

• I have read the CONTRIBUTING document.
• I have linked an issue to this PR.
• I have indicated the change type and relevant package(s).
• I have updated the documentation accordingly.
• I have added tests to cover my changes.
• All new and existing tests passed.
• All CI checks are green (linting, build/deploy, etc).
• At least one core contributor has approved this PR.

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[supernova-at]

Honestly I prefer this solution:

Create a new Guest Cart during checkout/reset

This action gets triggered when the Continue Shopping button is clicked.

but I wanted to get a solution up quickly to discuss the options.

[sirugh]

I'm a little confused -- what was the actual source of the error?

[supernova-at]

I'm a little confused -- what was the actual source of the error?

Oh, sorry - each cart has an id. After submitting an order, we wipe out that cart's id. When you attempt to add a new item, the error is that you can't because you don't have a cart.

In the current code we catch that error, create a new cart, and then retry adding the item. But we don't do any of that in redux, which is where the new backstop error notification reducer is looking to see if the error got handled. It thinks that the error went unhandled, so it pops up the error notification.

The solution I prefer is to create a new cart when the "continue shopping" button is clicked.
This way when you attempt to add an item, a cart already exists and everyone is happy.

[sirugh]

The solution I prefer is to create a new cart when the "continue shopping" button is clicked.
This way when you attempt to add an item, a cart already exists and everyone is happy.

I think that makes a lot of sense!

[coveralls]

Coverage increased (+0.006%) to 71.13% when pulling 3125e62 on supernova/916 into 7174988 on release/2.0.