public void ChangeTurnTest() { TicTacToe ticTacToe = new TicTacToe(); ticTacToe.Player = 'X'; ticTacToe.ChangeTurn(); Assert.AreEqual(ticTacToe.Player, 'O'); ticTacToe.ChangeTurn(); Assert.AreEqual(ticTacToe.Player, 'X'); }