public static Position[] Tick(Position[] positions)
{
if (positions == null || positions.Length == 0)
{
return(new Position[0]);
}
// check the dead neighbours of positions if it needs to spawn new cells
var newLivePositions = new List <Position>();
foreach (var position in positions)
{
var deadNeighbours = position.GetNeighbourPositions().Where(p => !positions.Contains(p));
// spawn a new cell if it has 3 neighbours
newLivePositions.AddRange(deadNeighbours.Where(deadNeighbour => deadNeighbour.GetNeighbourPositions().Count(positions.Contains) == 3));
}
// check all the live cells, deci
return((from position in positions
let neighbourCount = position.GetNeighbourPositions().Count(positions.Contains)
where Cell.IsAlive(neighbourCount)
select position)
.Concat(newLivePositions)
.ToArray());
}
public void DeadCellWithThreeNeighboursShouldBecomeLive()
{
bool nextState = Cell.IsAlive(3);
Assert.That(nextState, Is.True);
}
public void LiveCellWithMoreThanThreeNighboursShouldDie(int noOfNeighbours)
{
bool nextState = Cell.IsAlive(noOfNeighbours);
Assert.That(nextState, Is.False);
}
public void LiveCellWithTwoOrThreeNeighbourShouldLive(int noOfNeighbours)
{
bool nextState = Cell.IsAlive(noOfNeighbours);
Assert.That(nextState, Is.True);
}
public void LiveCellWithLessThanTwoNeighbourShouldDie(int noOfNeighbours)
{
bool nextState = Cell.IsAlive(noOfNeighbours);
Assert.That(nextState, Is.False);
}