reset_nil_attributes_to_default

# File lib/rubygems/specification.rb, line 2718
  def reset_nil_attributes_to_default
    nil_attributes = self.class.non_nil_attributes.find_all do |name|
      !instance_variable_defined?("@#{name}") || instance_variable_get("@#{name}").nil?
    end

    nil_attributes.each do |attribute|
      default = self.default_value attribute

      value = case default
              when Time, Numeric, Symbol, true, false, nil then default
              else default.dup
              end

      instance_variable_set "@#{attribute}", value
    end

    @installed_by_version ||= nil
  end