public void When_NonEmptyLinkedList_has_single_item_Then_Tail_returns_None()
{
var firstItem = TestingUtilities.Random.Next();
var list = new NonEmptyLinkedList<int>(firstItem);
Assert.That(list.Tail.HasValue, Is.False);
}
public void When_NonEmptyLinkedList_has_single_item_Then_IsLast_returns_true()
{
var singleItem = TestingUtilities.Random.Next();
var list = new NonEmptyLinkedList<int>(singleItem);
Assert.That(list.IsLast, Is.True);
}
public void When_NonEmptyLinkedList_has_single_item_Then_Head_returns_that_item()
{
var singleItem = TestingUtilities.Random.Next();
var list = new NonEmptyLinkedList<int>(singleItem);
Assert.That(list.Head, Is.EqualTo(singleItem));
}
public void When_NonEmptyLinkedList_has_two_items_Then_Tail_returns_Some()
{
var firstItem = TestingUtilities.Random.Next();
var secondItem = TestingUtilities.Random.Next();
var list = new NonEmptyLinkedList<int>(firstItem, new NonEmptyLinkedList<int>(secondItem));
Assert.That(list.Tail.HasValue, Is.True);
}
public void When_NonEmptyLinkedList_has_multiple_items_Then_IsLast_returns_false()
{
var firstItem = TestingUtilities.Random.Next();
var secondItem = TestingUtilities.Random.Next();
var list = new NonEmptyLinkedList<int>(firstItem, new NonEmptyLinkedList<int>(secondItem));
Assert.That(list.IsLast, Is.False);
}
public void When_NonEmptyLinkedList_has_multiple_items_Then_items_can_be_enumerated()
{
var firstItem = TestingUtilities.Random.Next();
var secondItem = TestingUtilities.Random.Next();
var list = new NonEmptyLinkedList<int>(firstItem, new NonEmptyLinkedList<int>(secondItem));
var expected = (IEnumerable<int>) new[] { firstItem, secondItem };
var actual = new List<int>();
foreach (var item in list)
actual.Add(item);
Assert.That(actual, Is.EquivalentTo(expected));
}