public void GetHeadElementFromOneElementList_ReturnsElement()
{
T sampleValue = this.CreateSampleValue();
DLList <T> list = new DLList <T>();
list.Append(sampleValue);
T headValue = list.GetHead();
Assert.AreEqual(sampleValue, headValue);
}
public void GetHeadElementFromEmptyList_ThrowsInvalidOperationException()
{
DLList <T> list = new DLList <T>();
list.GetHead();
}