How to build core test database?

Question

Fifteen years writing Drupal code and yet I have never written unit tests. I have recently posted a couple core patches which require tests to be written for them - so good time to learn how to write PHPUnit tests.

I have a test environmnet set up and am able to successfully run core unit tests. I need to extend these tests which I can see is not very difficult; but I need to run against the "test db". I can see core Views test modules like views_test_config and views_test_data which have everything I need - but I cannot enable them (manually so I can verify what my test content is).

Is there a way to get a copy of the D9 default test database that is used for running core (kernel) tests against? Or, alternatively, some way to enable these modules?

Answer 1

I'm not sure if I understand your question correctly, but there is no "test db" as such other than what your test creates. The core test system installs a minimal Drupal site from scratch (the database URL for this can be set in the phpunit.xml file, a default template of which is in core/phpunit.xml.dist). This is independent of any existing sites, uses the "simpletest" installation profile and is created from scratch every time the test runs.

Your test's ::setUp() method then creates things like test users, content etc in this site.

If you extend the KernelTestBase or the BrowserTestBase class, you will see there is a class property named $requiredModules. If you set this to an array of module names, they will automatically be enabled as part of the setup process.

Answer 2

To allow installing test modules you need to set this in your $settings.php:

$settings['extension_discovery_scan_tests'] = TRUE;

[EDIT] - this does allow seeing all the test modules and i can now enabled them - but the test data and view is still not run.. ughh!!