ruby – 如何测试RSPEC中的类方法

>有没有更简洁的方法来测试以下内容？
有没有
相当于我可以继续通过的方法的主题
不同的参数和检查结果？
有没有办法避免不必要的描述呢？

谢谢

describe Buy do
   describe '.get_days' do
    it 'should get days' do
      Buy.get_days('Includes a 1-weeknight stay for up to 4 people')
      .should == 1
      end
    it 'should get days' do
      Buy.get_days('Includes a 1-night stay in a King Studio Room with stone fireplace')
      .should == 1
    end
    it 'should get days' do
      Buy.get_days('Includes 4 nights/5 days at the Finisterra Hotel for up to two adults and two children (staying in the same room)')
      .should == 4
    end
  end
end