similar products through taxes

similar_products.rb

Spree::Order.class_eval do
  def similiar_products(limit)
    # products -> tax_category -> tax_rates -> adjustments -> orders -> products
    tax_rates = self.products.map do |product|
      product.tax_category.tax_rates
    end.flatten

    adjustments = tax_rates.map(&:adjustments).flatten

    orders = adjustments.map(&:order).compact

    orders.map(&:products).flatten.first(limit)
  end
end