test: fix broken unit test

[mikemurray]

Resolves #681
Impact: critical
Type: test

Issue

tests are failing

Solution

• add missing dependencies
• fixed tests themselves as necessary

Breaking changes

none

Testing

1. Unit tests should pass
2. App should run and be usable

[mikemurray]

Fixed the unit and dockerfile issue. eslint issues are in another PR in the works

[willopez]

LGTM

[janus-reith]

I wonder which of the tests rely on babel? I removed the customized babel config on purpouse as it is not required anymore. If tests really rely on it, maybe we could find a way so it is not picked up by nextjs?

Or do you want to include a custom babel config either way?

[willopez]

@janus-reith there are only a few unit test that are running:

 PASS  lib/utils/variantById.test.js (5.81 s)
 PASS  lib/utils/cartItemsConnectionToArray.test.js (5.922 s)
 PASS  lib/utils/pagination.test.js (6.188 s)
 PASS  lib/utils/relayConnectionToArray.test.js
 PASS  lib/utils/isProductLowQuantity.test.js
 PASS  lib/utils/isProductBestseller.test.js
 PASS  lib/utils/isProductOnSale.test.js
 PASS  lib/utils/priceByCurrencyCode.test.js
 PASS  lib/utils/calculateRemainderDue.test.js

10 to be exact, if we can get those to pass without adding the config in this PR, that would be great.

[janus-reith]

@willopez Thanks, I also realized after taking another look which ones were meant.
@mikemurray also listed the remaining test locations in #683

I just looked at the nextjs with-jest example: https://github.com/vercel/next.js/tree/canary/examples/with-jest
There also is a babel config present in the root folder, which just uses presets: "next/babel". I'm not an expert on the tests tooling, so maybe that's actually the way to go.
If we would just use that one, the issue @mikemurray described in #685 should also be gone I think? (But didn't try yet).