[feature]: Cart Coupons

[sirugh]

Description

Adds the Coupon functionality to price adjustments.
Also updates price summary when a cart is added or removed.

Related Issue

Closes PWA-75.

Acceptance

Verification Stakeholders

Specification

Verification Steps

1. Add a product and go to /cart.
2. Add a coupon, pwa1423 if you are on the AWS deployed app.
3. See price summary updated and coupon appears with "remove" button.
4. Click remove
5. See price summary updated and coupon is removed.

Additional Steps:

The Field component did not provide adequate spacing for a scenario where two fields are aligned next to each other in a grid and one field has a label (or error message and the other doesn't).

In order to remedy this I added a min-height value to the field label style and made field components align their content to the start rather than be stretched by default.

Please ensure that Fields across Venia still appear correctly and that there are no regressions.

Screenshots / Screen Captures (if appropriate)

Checklist

• I have updated the documentation accordingly, if necessary.
• I have added tests to cover my changes, if necessary.

[PWAStudioBot]

	Messages
📖	Access a deployed version of this PR here. Make sure to wait for the "pwa-pull-request-deploy" job to complete.
📖	DangerCI Failures related to missing labels/description/linked issues/etc will persist until the next push or next nightly build run (assuming they are fixed).
📖	Associated JIRA tickets: PWA-75.

Generated by 🚫 dangerJS against 6965e02

[sirugh]

@dpatil-magento do you have a coupon enabled on the PR deployment that @schensley can use to test out the UI?

[dpatil-magento]

@sirugh I will create some and pass it to you all.

[schensley]

@sirugh UI looks good.
One (or two tiny things)

1. Please remove the parentheses around the "subtracted" amount in the Pricing Summary and denote the discount with the negative sign alone.
2. Please style the "Remove" action for (removing the coupon once it's been applied) to look like a link consistent with the current Venia styling of links.

Once done, this is approved by UX.

Thnx

[sirugh]

Please remove the parentheses around the "subtracted" amount in the Pricing Summary and denote the discount with the negative sign alone.

Done!

Please style the "Remove" action for (removing the coupon once it's been applied) to look like a link consistent with the current Venia styling of links.

I set the color of the text for the "remove link" to --venia-text. We don't have a --venia-link that I could tell. This direction will probably come from the style guide and be updated in the future (as a new ticket/work item).

Thanks!

[sirugh]

Might have just found a bug -- when you add a coupon it doesn't show the remove view, at least not on the aws deployed version. I'll have to fix that and check why the tests didn't catch it.

[jimbo]

Might have just found a bug -- when you add a coupon it doesn't show the remove view, at least not on the aws deployed version. I'll have to fix that and check why the tests didn't catch it.

Did your latest commit fix this?

[jimbo]

Looks good. We'll eventually have an official "quiet" style for our buttons defined in the styleguide; this works for now.

[schensley]

Approved by UX.