public void TourMustNotContainInvalidNodeIndicesAfterInitialisation()
{
// arrange
var data = ProblemData();
var roulette = Substitute.For<INodeSelector>();
var ant = new Ant(0, data, roulette);
// act
ant.Initialise(2);
// assert
Assert.IsFalse(ant.Tour.Any(n => n == -1));
}
public void TourLengthShouldBeZeroAfterInitialisation()
{
// arrange
const int startNode = 4;
var data = ProblemData();
var roulette = Substitute.For<INodeSelector>();
var ant = new Ant(0, data, roulette);
// act
ant.Initialise(startNode);
// assert
Assert.AreEqual(0.0, ant.TourLength);
}
public void CurrentNodeShouldReturnCorrectIndex()
{
// arrange
const int currentNode = 3;
var data = ProblemData();
var roulette = Substitute.For<INodeSelector>();
var ant = new Ant(0, data, roulette);
roulette.SelectNextNode(ant).Returns(currentNode);
// act
ant.Initialise(7);
ant.Step(1);
// assert
Assert.AreEqual(currentNode, ant.CurrentNode);
}
public void StepShouldBuildCorrectTourLength()
{
// arrange
var expectedTour = new[] { 7, 3, 8, 2, 7 };
var roulette = Substitute.For<INodeSelector>();
var data = ProblemData();
var ant = new Ant(0, data, roulette);
// act
ant.Initialise(7);
for (var i = 1; i < expectedTour.Length; i++)
{
roulette.SelectNextNode(ant).Returns(expectedTour[i]);
ant.Step(i);
}
// assert
Assert.AreEqual(8, ant.TourLength);
Assert.AreEqual(expectedTour, ant.Tour);
}
public void TourShouldHaveOnlyStartNodeAfterInitialisation()
{
// arrange
const int startNode = 2;
var data = ProblemData();
var roulette = Substitute.For<INodeSelector>();
var ant = new Ant(0, data, roulette);
// act
ant.Initialise(startNode);
// assert
Assert.AreEqual(new[] { startNode }, ant.Tour);
}
public void VisitedShouldReturnCorrectFlagsForAllAllNodes()
{
var visited = new[] { false, false, false, true, false, false, false, true, true, false };
var tourSoFar = new[] { 7, 3, 8 };
var roulette = Substitute.For<INodeSelector>();
var data = ProblemData();
var ant = new Ant(0, data, roulette);
// act
ant.Initialise(7);
for (var i = 1; i < tourSoFar.Length; i++)
{
roulette.SelectNextNode(ant).Returns(tourSoFar[i]);
ant.Step(i);
}
Assert.AreEqual(visited, ant.Visited);
}
/// <summary>
/// Ants are compared on TourLength.
/// </summary>
/// <param name="other"></param>
/// <returns></returns>
public int CompareTo(Ant other)
{
return other != null ? TourLength.CompareTo(other.TourLength) : 1;
}
