public void _Prefetch_MovingIteratorWithEnumeratorBehavesCorrectly(Func <IEnumerable <int> > trackedIterationFactory)
{
var iter = new PreFetchFirstElementEnumerable <int>(trackedIterationFactory()); StateShouldBe(0, 1, 0);
var itEnum = iter.GetEnumerator(); StateShouldBe(0, 1, 0);
itEnum.MoveNext().Should().BeTrue(); StateShouldBe(0, 1, 0);
itEnum.Current.Should().Be(10); StateShouldBe(0, 1, 0);
itEnum.Current.Should().Be(10); StateShouldBe(0, 1, 0);
itEnum.Current.Should().Be(10); StateShouldBe(0, 1, 0);
itEnum.MoveNext().Should().BeTrue(); StateShouldBe(1, 1, 1);
itEnum.Current.Should().Be(20); StateShouldBe(1, 1, 1);
itEnum.MoveNext().Should().BeTrue(); StateShouldBe(2, 1, 1);
itEnum.Current.Should().Be(30); StateShouldBe(2, 1, 1);
itEnum.MoveNext().Should().BeTrue(); StateShouldBe(3, 1, 1);
itEnum.MoveNext().Should().BeFalse(); StateShouldBe(-2, 1, 1);
ResetState();
itEnum = iter.GetEnumerator(); StateShouldBe(0, 1, 0);
itEnum.MoveNext().Should().BeTrue(); StateShouldBe(0, 1, 0);
itEnum.MoveNext().Should().BeTrue(); StateShouldBe(1, 1, 1);
itEnum.Current.Should().Be(20); StateShouldBe(1, 1, 1);
itEnum.MoveNext().Should().BeTrue(); StateShouldBe(2, 1, 1);
itEnum.Current.Should().Be(30); StateShouldBe(2, 1, 1);
ResetState();
iter = new PreFetchFirstElementEnumerable <int>(trackedIterationFactory()); StateShouldBe(0, 1, 0);
itEnum = iter.GetEnumerator(); StateShouldBe(0, 1, 0);
itEnum.MoveNext().Should().BeTrue(); StateShouldBe(0, 1, 0);
itEnum.MoveNext().Should().BeTrue(); StateShouldBe(1, 1, 1);
itEnum.Current.Should().Be(20); StateShouldBe(1, 1, 1);
itEnum.MoveNext().Should().BeTrue(); StateShouldBe(2, 1, 1);
itEnum.Current.Should().Be(30); StateShouldBe(2, 1, 1);
}
public void _Prefetch_InvokingAPrefetchedIteratorDoesChangePositionAndDoesExecuteFirstStep(Func <IEnumerable <int> > trackedIterationFactory)
{
_iteratorPosition.Should().Be(-1);
var iter = new PreFetchFirstElementEnumerable <int>(trackedIterationFactory());
_iteratorPosition.Should().Be(0);
_executeFirstStep.Should().Be(1);
_executeSecondStep.Should().Be(0);
}
