Symfony2 Unit Testing Compiler Passes

Question

Does anyone have any advice for how to unit test a Symfony2 CompilerPassInterface::process() instance?

In particular, the ones I want to test generally deal with tagged items, adding method calls to a "manager" service.

Answer 1

If you want to test it in isolation, you'll have to mock the ContainerBuilder, and mock any service definition it returns.

That's usually quite annoying though. So I would tend to write an integration test instead. And in fact, that's what most of the compiler pass tests of symfony core do as well.

You would:

• Create an instance of ContainerBuilder
• Register some stub services
• Create the compiler pass
• Call $pass->process($container);
• Assert that the pass did its thing correctly

For an example of this, take a look at the RemoveUnusedDefinitionsPassTest.