public void Test6DoBattle()
        {
            Fleet        stackA         = zoneStacks[0] as Fleet;
            Fleet        stackB         = zoneStacks[1] as Fleet;
            List <Fleet> battlingFleets = new List <Fleet>();

            battlingFleets.Add(stackA);
            battlingFleets.Add(stackB);

            double distanceS, distanceE;

            distanceS = PointUtilities.Distance(stackA.Position, stackB.Position);

            battleEngine.DoBattle(zoneStacks);

            distanceE = PointUtilities.Distance(stackA.Position, stackB.Position);

            // Check that the fleets have moved towards each other.

            Assert.Greater(distanceS, distanceE);
        }