module DeepDup
  refine ::Hash do
    def deep_dup
      each_with_object(dup) do |(key, value), hash|
        hash[key] = if value.is_a?(::Hash) || value.is_a?(::Array)
                      value.deep_dup
                    else
                      value
                    end
      end
    end
  end
end

module TestRefinement
  using DeepDup

  def self.run
    source = {
      a: 1,
      b: 'hello',
      c: {
        id: 1,
        data: { name: 'John' }
      }
    }

    source.deep_dup
  end
end

TestRefinement.run

puts "All OK"