Testing for elements in ActiveRecord's XML output

Following on from my previous post about customising ActiveRecord’s to_xml output, I have had to write specs to make sure a custom attribute I have added to a model’s XML serialisation actually appears as expected.

ActiveSupport’s Hash.from_xml class method makes this a piece of cake. Instead of testing against the XML as a string or parsing it manually, you can turn it into a hash and get directly to the attribute you want. Behold:

describe Product do
  before(:each) do
    @product = Product.new
  end

  # net_price is the custom attribute I have added to the XML serialisation
  it "should include net price in XML serialisation" do
    @product.attributes = valid_product_attributes
    Hash.from_xml(@product.to_xml)['product']['net_price'].should == @product.net_price
  end
end