public void SingleOrDefaultWithPredicateWorksLikeWhereFollowedBySingleOrDefault()
{
var tracker0 = new TrackingEnumerable(10);
var pred0 = new CountedFunction <int, bool>(i => i > 2);
Assert.Throws <InvalidOperationException>(() => tracker0.SingleOrDefault(pred0.Func));
var tracker1 = new TrackingEnumerable(10);
var pred1 = new CountedFunction <int, bool>(i => i > 2);
Assert.Throws <InvalidOperationException>(() => tracker1.Where(pred1.Func).SingleOrDefault());
// .NET Core shortcircuits as an optimization.
// See https://github.com/dotnet/corefx/pull/2350.
Assert.Equal(tracker0.Moves, tracker1.Moves);
Assert.Equal(pred0.Calls, pred1.Calls);
}
