Rails STI validation inheritance

I have STI model开发者_如何转开发s in my Rails application. The ancestor model has validations with the validates_... methods which are working fine.

But I have custom validations as well, and I would like to add more different custom validations in the descendants. These custom validations would depend on the class.

If I write

class DescendantA < Ancestor

  protected
    def validate
      # ...
    end
end

It simply overwrites the original validations, so I loose the original inherited validations.

Is there a convention to do this in Rails?

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Would it not be sufficient to add super at the end of the validate method in the child, so that the parent's validate method would also be called?