public void RelocatePage_SuccessiveRelocates_BothWork()
{
var book = CreateBook();
var pages = book.GetPages().ToArray();
book.RelocatePage(pages[1], 0);
book.RelocatePage(pages[2], 1);
var newPages = book.GetPages().ToArray();
Assert.AreEqual(pages[1].Id, newPages[0].Id);
Assert.AreEqual(pages[2].Id, newPages[1].Id);
Assert.AreEqual(pages[0].Id, newPages[2].Id);
Assert.AreEqual(3, pages.Length);
}