public void UnitTest1()
    {
        // ARRANGE
        using var item1 = new CapturedItem();
        using var list  = new ObservableList <CapturedItem>
              {
                  AutomaticallyCaptureSubItems = true,
              };

        // ACT
        list.Add(item1);

        item1.TestProperty = "aaa";
        item1.TestProperty = "bbb";
        item1.TestProperty = "ccc";

        list.Undo();

        // ASSERT
        Assert.Equal(
            "bbb",
            item1.TestProperty);
    }
 public NewItemCreatedEventArgs(CapturedItem item)
 {
     this.Item = item;
 }