dtryon

                if (count < 2 || count > 3) {
                    _grid[x][y] = 0;
                }

                if (count === 3) {
                    _grid[x][y] = 1;
                }

dtryon

    describe('Any dead cell with exactly three live neighbours becomes a live cell, as if by reproduction.', function () {

        it('should set cell with three live neighbours on different rows', function () {
            game.setCell(2,2);
            game.setCell(3,4);
            game.setCell(4,4);

            game.nextFrame();
            expect(game.grid()[3][3]).toBe(1);
        });

dtryon

                if (count < 2 || count > 3) {
                    _grid[x][y] = 0;
                }

dtryon

    describe('Any live cell with more than three live neighbours dies, as if by overcrowding.', function () {

		it('should kill cell with four live neighbours on different rows', function () {
			game.setCell(2,2);
			game.setCell(3,4);
			game.setCell(4,4);
			game.setCell(4,3);

			game.setCell(3,3);
			game.nextFrame();

dtryon

describe('Any live cell with two or three live neighbours lives on to the next generation.', function () {

        it('should save cell with two live neighbours', function () {
            game.setCell(3,2);
            game.setCell(3,4);

            game.setCell(3,3);
            game.nextFrame();
            expect(game.grid()[3][3]).toBe(1);
        });

dtryon

                if (count < 2) {
                    _grid[x][y] = 0;
                }

dtryon

    var nextFrame = function () {

        function countRow(row, prevColumn, nextColumn, isNotCurrent) {
            var result = 0;
            if (row) {
                if (prevColumn) {
                    result += row[prevColumn];
                }
                if (nextColumn) {
                    result += row[nextColumn];

dtryon

    describe('Any live cell with fewer than two live neighbours dies, as if caused by under-population.', function () {
        it('should kill cell with no live neighbours', function () {
            game.setCell(3,3);
            game.nextFrame();
            expect(game.grid()[3][3]).toBe(0);
        });

        it('should kill cell with one live neighbour', function () {
            game.setCell(3,2);

dtryon

var Game = (function () {
 
    var _grid;
 
    //...some existing code

    var setCell = function (x, y) {
        _grid[x][y] = 1;
    };
 

dtryon

describe('Game of Life', function () {

	var game;

	beforeEach(function () {
		game = Game(30);
	});

        //...other tests