testing2.rb

def assert(actual, expected)
  if actual == expected
    puts "#{actual.inspect} equals #{expected.inspect}"
  else
    raise "Expected #{actual.inspect} to equal #{expected.inspect}"
  end
end

LIVE = 'X'
DEAD = 'O'

def alive?(point, live_neighbor_count)
  if point == LIVE
    return false if (live_neighbor_count < 2 || live_neighbor_count > 3)
    return true if (live_neighbor_count == 2 || live_neighbor_count == 3)
  else
    live_neighbor_count == 3
  end
end

def live_neighbor_count(x, y, board)
  neighbors = get_neighbors(x, y)
  filter_neighbors(neighbors, board).count { |rindex, cindex| board[rindex][cindex] == LIVE }
end

def filter_neighbors(neighbors, board)
  neighbors.select do |rindex, cindex|
    rindex >= 0 && rindex < board.length && cindex >= 0 && cindex < board[rindex].length
  end
end

def get_neighbors(x, y)
  [
  [x, (y+1)],
  [x, (y-1)],
  [(x-1), y],
  [(x+1), y],
  [(x+1), (y+1)],
  [(x-1), (y-1)],
  [(x+1), (y-1)],
  [(x-1), (y+1)]
]
end

def evolve(board)
  board.map.with_index do |row, row_index|
    row.map.with_index do |point, column_index|
      live_neighbors = live_neighbor_count(row_index, column_index, board)
      (alive?(point, live_neighbors)) ? LIVE : DEAD
    end
  end
end


#testing evolve
board = [%w(O)]
assert(evolve(board), [%w(O)])

board = [%w(X)]
assert(evolve(board), [%w(O)])

board = [%w(X X X)]
assert(evolve(board), [%w(O X O)])

board = [%w(X O X), %w(X X O), %w(X O X)]
expected = [%w(X O O), %w(X O X), %w(X O O)]
assert(evolve(board), expected)
#get_live_count counts horizontal neighbors
board = [%w(O X O)]
assert(live_neighbor_count(0, 0, board), 1)
assert(live_neighbor_count(0, 1, board), 0)
assert(live_neighbor_count(0, 2, board), 1)

#get_live_count counts vertical neighbors
board = [%w(O), %w(X), %w(O)]
assert(live_neighbor_count(0, 0, board), 1)
assert(live_neighbor_count(1, 0, board), 0)
assert(live_neighbor_count(2, 0, board), 1)

#get_live_count counts diagonal neighbors
board = [%w(O X), %w(X O)]
assert(live_neighbor_count(0, 1, board), 1)
assert(live_neighbor_count(1, 0, board), 1)

board = [%w(X O), %w(O X)]
assert(live_neighbor_count(0, 0, board), 1)
assert(live_neighbor_count(1, 1, board), 1)


#Rule #1 - Living cell dies if surrounded by less than 2 living cells
point = LIVE
live_neighbor_count = 0
assert(alive?(point, live_neighbor_count), false)

point = LIVE
live_neighbor_count = 1
assert(alive?(point, live_neighbor_count), false)

# Rule 2 - Living cell stays alive if surrounded by 2 or 3 living cells
point = LIVE
live_neighbor_count = 2
assert(alive?(point, live_neighbor_count), true)

point = LIVE
live_neighbor_count = 3
assert(alive?(point, live_neighbor_count), true)

# Rule 3 - Living cell dies if surrounded by more than 3 living cells
point = LIVE
live_neighbor_count = 4
assert(alive?(point, live_neighbor_count), false)

# Rule 4 - Dead cell comes alive if surrounded by exactly 3 living cells
point = DEAD
live_neighbor_count = 3
assert(alive?(point, live_neighbor_count), true)

#"Rule 5" - Dead cell stays dead if surrounded by anything but 3 living cells
point = DEAD
live_neighbor_count = 2
assert(alive?(point, live_neighbor_count), false)

point = DEAD
live_neighbor_count = 4
assert(alive?(point, live_neighbor_count), false)







# # Rule #1
# # assert(evolve([%w(X O), %w(O O)]), [%w(O O), %w(O O)])
# board = [%w(X O), %w(O O)]
# assert(alive?(0, 0, board), false)

# # assert(evolve([%w(O O), %w(O X)]), [%w(O O), %w(O O)])
# board = [%w(O O), %w(O X)]
# assert(alive?(1, 1, board), false)

# #assert(evolve([%w(O O O), %w(O X O), %w(O O O)]), [%w(O O O), %w(O O O), %w(O O O)])
# board = [%w(O O O), %w(O X O), %w(O O O)]
# assert(alive?(1, 1, board), false)

# # Rule 2
# # assert(evolve([%w(X X X)]), [%w(O X O)])
# board = [%w(X X X)]
# assert(alive?(0, 0, board), false)
# assert(alive?(0, 2, board), false)
# assert(alive?(0, 1, board), true)


# # assert(evolve([%w(O X O), %w(O X O), %w(O X O)]), [%w(O O O), %w(O X O), %w(O O O)])
# board = [%w(O X O), %w(O X O), %w(O X O)]
# assert(alive?(0, 1, board), false)
# assert(alive?(2, 1, board), false)
# assert(alive?(1, 1, board), true)

# # assert(evolve([%w(O X O), %w(O X X)]), [%w(O X O), %w(O X X)])
# board = [%w(O X O), %w(O X X)]
# assert(alive?(0, 2, board), false)

# # assert(evolve([%w(O X O), %w(X X O)]), [%w(O X O), %w(X X O)])
# board = [%w(O X O), %w(X X O)]
# assert(evolve(board), board)
# #Here ends pairing

# # assert(evolve([%w(X O X), %w(O X O), %w(X O O)]), [%w(O O O), %w(O X O), %w(O O O)])
# board = [%w(X O X), %w(O X O), %w(X O O)]
# assert(alive?(0, 0, board), false)
# assert(alive?(0, 2, board), false)
# assert(alive?(2, 0, board), false)

# #Rule 3
# # assert(evolve([%w(X O X), %w(O X O), %w(X O X)]), [%w(O O O), %w(O O O), %w(O O O)])
# board = [%w(X O X), %w(O X O), %w(X O X)]
# assert(alive?(1, 1, board), false)

# puts "Test passed."