Omnipay-common gateway proper way to test before live with current project

Question

I'm implementing my own gateway package for https://github.com/thephpleague/omnipay-common.

I've cloned the Stripe repo because my gateway has many similarities. So I cloned it and moved it into a sub folder for my project to test it with laravel My gateway package works and I can use it with laravel but I want to fix the tests.

I'm wondering how I run the test? It shows that it needs to "use Omnipay/Test/TestCase"

However, when I clone the repo NO Omnipay/Tests gets downloaded.

And apparently there should be an Omnipay/Tests/GatewayTestCase

How do I get these files?

I added the Omnipay/tests to the main project and that seemed to work.

How do I add it to gitlab for me to test privately as a composer request.

Basically I want to test it with my laravel app before making it public?

Thanks