Should the acceptance tests be in the same repo as the product itself?

Question

PHP

Should automated acceptance testing be in the same repository as the application, i.e. for the application to test itself, or should these tests go separately so that any application instance can be tested with one test instance?

Answer 1

In general, yes. Because:
1. Conceptually. The test suite is part of the application, and without it they don't make sense
2. Methodologically. Convenience of single versioning: change the behavior of the application, change tests in the same version.
3. Process. It's easier to automate processes by cloning one rep and run them locally by hand.
Exceptions:
- the product is implemented in the form of several prototypes, for example, in different languages ​​and in different turnips. Then the tests do not belong to any of them, it is logical to store them separately.
- the product has a microservice architecture, and it is impossible to single out which service (repository) is the main entry point for acceptance tests.

Answer 2

Quite often, the application and tests are written in different languages ​​and use different environments.