public void CanFilterByParentItem()
{
ParentFilter filter = new ParentFilter(child1);
filter.Filter(allItems);
Assert.AreEqual(3, allItems.Count);
}
public void CanFilterByParentID(int parentID, int expectedCount)
{
ParentFilter filter = new ParentFilter(parentID);
filter.Filter(allItems);
Assert.AreEqual(expectedCount, allItems.Count);
}