public void Set_DidHaveForm_StillJustOneCopy()
{
var htmlDom = new HtmlDom();
var data = new BookData(htmlDom, new CollectionSettings(), null);
data.Set("1", "one", "en");
data.Set("1", "one", "en");
Assert.AreEqual("one", data.GetVariableOrNull("1", "en"));
AssertThatXmlIn.Dom(htmlDom.RawDom).HasSpecifiedNumberOfMatchesForXpath("//div[@lang='en']", 1);
var roundTripData = new BookData(htmlDom, new CollectionSettings(), null);
var t = roundTripData.GetVariableOrNull("1", "en");
Assert.AreEqual("one", t);
}