Autoloader: Renaming the main extension files

[wjrosa]

Fixes STRIPE-506
Base PR #4260

Changes proposed in this Pull Request:

As part of the autoloader implementation, this PR renames all the main extension files to follow the PSR-4 autoloading standard. The goal of this change is to implement the default composer autoloader in a following PR.

Testing instructions

Code review. Check if the tests are still passing.

Perform some smoking testing to make sure no regression was introduced:

• Connect a Stripe account
• Toggle some payment methods
• Toggle legacy checkout
• Perform some purchases in both shortcode and block checkout
• Try simple products, subscriptions, and pre-orders

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• Covered with tests (or have a good reason not to test in description ☝️)
• Tested on mobile (or does not apply)

Changelog entry

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Changelog Entry Comment

Comment

Post merge

• Added testing instructions to the Release Testing Instructions wiki page (or does not apply)
• Added the needs docs label (or does not apply)
• Included this PR in the Release Thread scope (or does not apply)

[malithsen]

Thanks for putting this together! Smoke tests were successful!

Given the scope of these file renames, I’m wondering if we should hold these off from the next release. Large-scale renames can sometimes surface subtle, hard-to-debug issues. We should probably discuss this with the team :)

[wjrosa]

Thank you for your review, Malith!

Given the scope of these file renames, I’m wondering if we should hold these off from the next release. Large-scale renames can sometimes surface subtle, hard-to-debug issues. We should probably discuss this with the team :)

Absolutely, that was the plan. This will be merged only after Dale's PR lands. And I will outline the whole rollout plan on a P2 soon

[github-actions]

📈 PHP Unit Code Coverage Report

Package	Line Rate	Health
includes/WC_Stripe_Customer.php	40%	❌
Summary	44% (7261 / 16496)	❌