WIP - Introduce tests on platforms

[VincentLanglet]

Related to #506 (comment) @janedbal,
I try to introduce tests on different platform. Does this solution would work for you ?

Edit: Are you also ok with this solution @ondrejmirtes ?
I had in mind to provide @group platform on every platform tests, each with a special group like @group sql.
And adding all different platform in github actions.

[VincentLanglet]

Currently I extends PDOQueryResultTypeWalkerTest but later we'll work his own dataprovider

[janedbal]

We definitelly need to check "before 8.1" and "after 8.1" as there were some major changes.

[janedbal]

We definitelly need entities suited for platform testing (having float, decimal, bool, int, bigint columns).

[janedbal]

I'm not sure we need this complexity. I ended with super simple test fetching a single expression and verifying that type in https://github.com/janedbal/php-database-drivers-fetch-test All we need here is to check that against the inferred PHPStan type.

And I feel this is the best approach to accomplish what we need as it can be quite readable in the test itself

[VincentLanglet]

I just copied the existing QueryResultTypeWalkerTest with the whole dataprovider.

Do you think we should split it ?

• Only single expression for platforms tests
• single expression and complex expression for PDO tests in order to validate PHPStan for these

I thought this was better to keep the same data for every platform.

[janedbal]

The matrix (at some level) should also contain:

• driver (there are more for mysql and pgsql and some of them behave differently)
• config (mainly stringification on/off for PDO drivers)

[VincentLanglet]

The matrix (at some level) should also contain:

• config (mainly stringification on/off for PDO drivers)

Since the config must be passed to the entity manager in a entity-manager.php passed to phpstan in config with

parameters:
	doctrine:
		objectManagerLoader: entity-manager.php

I don't see how it would be in the matrix.

Currently, the only solution I see is to create one entityManager for every platform/config and one test case for every entityManager...