public virtual void TestOrdersIncludeDetailsWithGroupBy()
{
var list = db
.Orders
.Include(o => o.Details)
.Where(o => o.CustomerID == "ALFKI")
.GroupBy(o => o.CustomerID)
.ToList();
AssertValue(1, list.Count);
var grp = list[0].ToList();
AssertValue(6, grp.Count);
var o10643 = grp.SingleOrDefault(o => o.OrderID == 10643);
Assert.AreNotEqual(null, o10643);
AssertValue(3, o10643.Details.Count());
}