public void Simple()
{
var data = new List <Task>
{
new Task {
Title = "task1"
}
};
var groupBuilder = new GroupBuilder <Task>(
p => p.Title,
p => p.Title,
(g1, g2) => g1.Title.CompareTo(g2.Title),
(p1, p2) => p1.Title.CompareTo(p2.Title));
var collection = new SmartCollection <Task>(data, groupBuilder, t => !t.Completed.HasValue);
Assert.AreEqual(1, collection.Items.Count);
Assert.AreEqual(1, collection.Items[0].Count);
Assert.AreEqual("task1", collection.Items[0][0].Title);
data[0].IsCompleted = true;
collection.InvalidateItem(data[0]);
Assert.AreEqual(0, collection.Items.Count);
data[0].IsCompleted = false;
collection.InvalidateItem(data[0]);
Assert.AreEqual(1, collection.Items.Count);
Assert.AreEqual(1, collection.Items[0].Count);
Assert.AreEqual("task1", collection.Items[0][0].Title);
}