Fix configurable dropdown showing tax incorrectly in 2.3-develop

[danielpfarmer]

Description (*)

This pull request addresses an issue described in #22270 and introduced in #17695.

The issue is that the price increase calculation was previously based upon the configurable basePrice vs the optionFinalPrice rather than the configurable finalPrice vs the optionFinalPrice. This meant that the tax amount was also been added to the price difference calculation for each of the configurable options incorrectly.

Fixed Issues (if relevant)

1. 2.2.8 Configurable product option dropdown - price difference incorrect when catalog prices are entered excluding tax #22270: 2.2.8 Configurable product option dropdown - price difference incorrect when catalog prices are entered excluding tax

Manual testing scenarios (*)all Magento 2.

2. Set prices to be entered excluding tax in the configuration.
3. Apply product tax using tax rules.
4. Create a configurable product configurable by only one dropdown attribute (e.g colour or size)
5. Ensure that the product tax is not added for a second time in the dropdown attribute

Contribution checklist (*)

• Pull request has a meaningful description of its purpose
• All commits are accompanied by meaningful commit messages
• All new or changed code is covered with unit/integration tests (if applicable)
• All automated tests passed successfully (all builds on Travis CI are green)

[m2-assistant]

Hi @danielpfarmer. Thank you for your contribution
Here is some useful tips how you can test your changes using Magento test environment.
Add the comment under your pull request to deploy test or vanilla Magento instance:

• @magento-engcom-team give me test instance - deploy test instance based on PR changes
• @magento-engcom-team give me 2.3-develop instance - deploy vanilla Magento instance

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[magento-cicd2]

All committers have signed the CLA.

[magento-engcom-team]

Hi @VladimirZaets, thank you for the review.
ENGCOM-4809 has been created to process this Pull Request

[magento-engcom-team]

@danielpfarmer thank you for contributing. Please accept Community Contributors team invitation here to gain extended permissions for this repository.

[VasylShvorak]

✔️ QA passed

[m2-assistant]

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[EvaldasDau]

Well this still doesn't solve the issue. Only the first item in the configurable product drop down is gets fixed.

[danielpfarmer]

@EvaldasDau can you give more detail / Steps to replicate? Cheers

[EvaldasDau]

@danielpfarmer Hey, thanks for reply.

We applied the changes to m2 2.3.1 store local installation, ran setup upgrade and cleaned cache.

Then when checking configurable products with drop down size options, noticed that the first option value was fixed; the + tax amount value no longer was displayed, however rest of the size options still had it.