Validation is implemented for a class bean, and partially for a producer when its type is an array or primitive.
The following case is not covered by validation.

public class TestBean {

    @Inject
    String s;

    @Produces
    @RequestScoped
    String getString() {
        return "x";
    }

}

Implementation for class bean is not correct. It checks if injected bean type is proxyable, but instead it should check if the type of injection point is proxyable.