public void ExpressionlessSourceManipulation()
{
var numbers = new ObservableDictionary <int, int>();
using var aggregate = numbers.ActiveSum();
Assert.IsNull(aggregate.OperationFault);
Assert.AreEqual(0, aggregate.Value);
numbers.Add(1, 1);
Assert.IsNull(aggregate.OperationFault);
Assert.AreEqual(1, aggregate.Value);
numbers.AddRange(System.Linq.Enumerable.Range(2, 3).ToDictionary(i => i));
Assert.AreEqual(10, aggregate.Value);
numbers.RemoveRange(new int[] { 1, 2 });
Assert.AreEqual(7, aggregate.Value);
numbers.Remove(3);
Assert.AreEqual(4, aggregate.Value);
numbers.Reset(System.Linq.Enumerable.Range(1, 3).ToDictionary(i => i));
Assert.AreEqual(6, aggregate.Value);
}
