Optionally generate AssertJ assertions for generated Immutable types

It would be really cool, if at the same time as generating the immutable classes, custom assertions could be generated. AssertJ has an implementation which could be run from the annotation processor. This would mean clean tests when using in the same project or downstream.

Not sure how it would work. Maybe the processor could detect the presence of an assertion generator (AssertJ/Google Truth etc) and then generate.

There could be a an assertion flag on @Style? or a new annotation?

Many ways to do it.

[asereda-gs]

Can you show some example of assertions you want to be executed ? Why do they have to be run from annotation processor ?

[cal101]

Thanks for the pointer to the evaluator. It should indeed be possible to enhance that for assertJ like expressive messages.

From what I remember from the assertj inner workings it’s more comparable to the let’s say builder code generated by immutables. There is no “runtime system” or “evaluator” that can be “programmed”. It’s static code that allows writing fluent assertions and the error reporting is baked in.