Let's assume there is a trait MyTrait implemented by for the AnImpl struct.
I want to implement a decorator pattern over the AnImpl. Let's call this new type TheDecorator.

I want the TheDecorator to implement every MyTrait method. Some will be trivially delegated to the inner AnImpl instance, some not (depending on the logic of the decorator). I do not want the TheDecorator to rely on any MyTrait default method.

So far this is easy -- just implement every method. Let's now assume that MyTrait is expected to evolve, possibly gaining new default methods. How to make sure the TheDecorator remains "fully implemented", i.e. maintains the invariant that it does not rely on any MyTrait default method?

Context:
I am coming from Java background where decorators are idiomatic. Having automated checks for invariants as above saved my day many times over. I don't find decorators anti-idiomatic in Rust and so would love to have these checks.

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