public void GetThreatsFuzzTest()
{
Random random = new Random(0);
const int gameLimit = 200;
for (int game = 1; game < gameLimit; game++)
{
Grid_Accessor grid = new Grid_Accessor(new PrivateObject(new Grid(7, 6, 0)));
// Play a full random, game, and verify threats after each move.
for (int i = 0; i < 7 * 6 && grid.IsGameOver() == -1; i++)
{
ValidateThreats(grid, 0);
ValidateThreats(grid, 1);
int move;
do
{
move = random.Next(grid.Width);
} while (!grid.IsValidMove(move));
int player = i & 1;
grid.Move(move, player);
}
}
}
private void ValidateThreats(Grid_Accessor grid, int player)
{
ulong threats = grid.GetThreats(player);
for (int i = 0; i < (grid.Height + 1) * grid.Width; i++)
{
ulong mask = 1UL << i;
bool isThreat = (threats & mask) == mask;
bool isInBuffer = ((i + 1) % (grid.Height + 1)) == 0;
if (isThreat)
{
Assert.AreEqual(0UL, grid.playerPositions[0] & mask,
"Player cannot have a threat in a nonempty location");
Assert.AreEqual(0UL, grid.playerPositions[1] & mask,
"Player cannot have a threat in a nonempty location");
Assert.IsTrue(!isInBuffer,
"Cannot have a threat in the column buffer");
}
if (!isInBuffer)
{
ulong originalPosition = grid.playerPositions[player];
grid.playerPositions[player] |= mask & ~grid.playerPositions[1 - player];
Assert.AreEqual(isThreat, grid.IsGameOver(player));
grid.playerPositions[player] = originalPosition;
}
}
Assert.AreEqual(0UL, threats >> ((grid.Height + 1) * grid.Width),
"Threats must be on the board");
}