I'm experimenting with this right now, and trying to go off of other extensions that do db stuff. It might be closer to an integration test, but if it works...

I'll let you know if I figure anything out!

So I was just going to do it like I did in PageArchiveTest.php (create revisions with new Revision() which in turn would populate cuc_changes). There's some magic somewhere in core that creates all the default.unittest_whatever tables, and you specify which ones should be truncated with $this->tablesUsed. default.unittest_cuc_changes however does not exist. Do we know how to make it create this table?

CI does:

• clone mediawiki
• maintenance/install.php
• tweak LocalSettings.php to enable extensions
• maintenance/update.php (which creates the extension database tables)
• run phpunit

The magic is in tests/phpunit/MediaWikiTestCase.php. When your test class as a @databases it clones database tables with a unittest_ prefix so your tests run against a copy of the installed DB.

To inject data to the database, in your test class you can use one of:

MediaWikiTestCase::addDBDataOnce()
MediaWikiTestCase::addDBData()

You can look at tests/phpunit/includes/BlockTest.php which inserts some user/IP blocks which are then used to test the code logic.

@hashar Splendid!!! Thank you :)

Change 394918 had a related patch set uploaded (by MusikAnimal; owner: MusikAnimal):
[mediawiki/extensions/CheckUser@master] Start on basic unit tests for CheckUser extension

https://gerrit.wikimedia.org/r/394918

Change 394918 merged by jenkins-bot:
[mediawiki/extensions/CheckUser@master] Start on basic unit tests for CheckUser extension

https://gerrit.wikimedia.org/r/394918