public void When_creating_a_sub_array()
{
var srcArray = new[] { 1, 2, 3, 4, 5 };
var emptySub = new SubArray <int>(srcArray, 4, 0);
emptySub.ShouldBeEmpty();
emptySub.Segment.Array.ShouldBe(srcArray);
emptySub.Segment.Offset.ShouldBe(4);
emptySub.Segment.ShouldBeEmpty();
var subOne = new SubArray <int>(srcArray, 0, 2);
subOne.Length.ShouldBe(2);
subOne[0].ShouldBe(1);
subOne[1].ShouldBe(2);
subOne.Segment.Array.ShouldBe(srcArray);
subOne.Segment.Offset.ShouldBe(0);
subOne.Segment.Count.ShouldBe(subOne.Length);
var subTwo = new SubArray <int>(srcArray, 1, 3);
subTwo.Length.ShouldBe(3);
subTwo[0].ShouldBe(2);
subTwo[1].ShouldBe(3);
subTwo[2].ShouldBe(4);
subTwo.Segment.Array.ShouldBe(srcArray);
subTwo.Segment.Offset.ShouldBe(1);
subTwo.Segment.Count.ShouldBe(subTwo.Length);
// ReSharper disable once ObjectCreationAsStatement
Should.Throw <ArgumentException>(() => new SubArray <int>(srcArray, 3, 5))
.Message.ShouldBe("Offset and length were out of bounds for the array or count is greater than the number of elements from index to the end of the source collection.");
var subThree = new SubArray <int>(srcArray, 1, 4);
subThree.Length.ShouldBe(4);
subThree[0].ShouldBe(2);
subThree[1].ShouldBe(3);
subThree[2].ShouldBe(4);
subThree[3].ShouldBe(5);
subThree.Segment.Array.ShouldBe(srcArray);
subThree.Segment.Offset.ShouldBe(1);
subThree.Segment.Count.ShouldBe(subThree.Length);
}
