def test_board_open_positions(self): board = Board(size = 2) board.place_piece(Position(0, 0), Foo()) board.place_piece(Position(1, 1), Foo()) expected_positions = [Position(0, 1), Position(1, 0)] actual_positions = [p for p in board.open_positions()] self.assertItemsEqual(actual_positions, expected_positions)