Rspec Controller Test if xml is returned

describe UsersController do
  describe "handling GET /users.xml" do
    before(:each) do
      @users = mock("Array of Users", :to_xml => "XML")
      User.stub!(:find).and_return(@users)
    end

    def do_get
      @request.env["HTTP_ACCEPT"] = "application/xml"
      get :index
    end

    it "should render the found users as xml" do
      @users.should_receive(:to_xml).and_return("XML")
      do_get
      response.body.should == "XML"
    end
  end
end