optional_coercer.rb

  # An empty hash does not result in creating a new instance of the type.
  # Required because that's what we get back from the relation.
  class OptionalCoercer
    def initialize(type)
      @type = type
    end

    def call(value)
      return unless value
      value.values.any? ? type.new(value) : nil
    end

    def success?(primitive, value)
      value.is_a?(primitive)
    end
  end