Add game-of-life (#152)

Author: glennj

config.json

@@ -682,6 +682,14 @@
         "prerequisites": [],
         "difficulty": 5
       },
+      {
+        "slug": "game-of-life",
+        "name": "Conway's Game of Life",
+        "uuid": "a12cd1e2-4108-40ad-aa72-80706d1eeb30",
+        "practices": [],
+        "prerequisites": [],
+        "difficulty": 5
+      },
       {
         "slug": "crypto-square",
         "name": "Crypto Square",

exercises/practice/game-of-life/.busted

@@ -0,0 +1,5 @@
+return {
+  default = {
+    ROOT = { '.' }
+  }
+}

exercises/practice/game-of-life/.docs/instructions.md

@@ -0,0 +1,11 @@
+# Instructions
+
+After each generation, the cells interact with their eight neighbors, which are cells adjacent horizontally, vertically, or diagonally.
+
+The following rules are applied to each cell:
+
+- Any live cell with two or three live neighbors lives on.
+- Any dead cell with exactly three live neighbors becomes a live cell.
+- All other cells die or stay dead.
+
+Given a matrix of 1s and 0s (corresponding to live and dead cells), apply the rules to each cell, and return the next generation.

exercises/practice/game-of-life/.docs/introduction.md

@@ -0,0 +1,9 @@
+# Introduction
+
+[Conway's Game of Life][game-of-life] is a fascinating cellular automaton created by the British mathematician John Horton Conway in 1970.
+
+The game consists of a two-dimensional grid of cells that can either be "alive" or "dead."
+
+After each generation, the cells interact with their eight neighbors via a set of rules, which define the new generation.
+
+[game-of-life]: https://en.wikipedia.org/wiki/Conway%27s_Game_of_Life

exercises/practice/game-of-life/.meta/config.json

@@ -0,0 +1,19 @@
+{
+  "authors": [
+    "glennj"
+  ],
+  "files": {
+    "solution": [
+      "game_of_life.moon"
+    ],
+    "test": [
+      "game_of_life_spec.moon"
+    ],
+    "example": [
+      ".meta/example.moon"
+    ]
+  },
+  "blurb": "Implement Conway's Game of Life.",
+  "source": "Wikipedia",
+  "source_url": "https://en.wikipedia.org/wiki/Conway%27s_Game_of_Life"
+}

exercises/practice/game-of-life/.meta/example.moon

@@ -0,0 +1,30 @@
+Deltas = {
+  {-1, -1}, {-1, 0}, {-1, 1},
+  {0, -1},           {0, 1},
+  {1, -1},  {1, 0},  {1, 1}
+}
+
+tick = (matrix) ->
+  height = #matrix
+  return {} if height == 0
+  width = #matrix[1]
+
+  count_neighbours = (x, y) ->
+    count = 0
+    for d in *Deltas
+      dx, dy = x + d[1], y + d[2]
+      if 1 <= dx and dx <= height and 1 <= dy and dy <= width
+        count += matrix[dx][dy]
+    count
+
+  result = [{} for _ = 1, height]
+  for r = 1, height
+    for c = 1, width
+      result[r][c] = switch count_neighbours r, c
+        when 3 then 1
+        when 2 then matrix[r][c]
+        else 0
+  result
+
+
+{ :tick }

exercises/practice/game-of-life/.meta/spec_generator.moon

@@ -0,0 +1,14 @@
+import int_lists, word_list from require 'test_helpers'
+
+{
+  module_name: 'GameOfLife',
+
+  generate_test: (case, level) ->
+    lines = {
+      "matrix = #{int_lists case.input.matrix, level}"
+      "result = GameOfLife.#{case.property} matrix"
+      "expected = #{int_lists case.expected, level}",
+      "assert.are.same expected, result"
+    }
+    table.concat [indent line, level for line in *lines], '\n'
+}

exercises/practice/game-of-life/.meta/tests.toml

@@ -0,0 +1,34 @@
+# This is an auto-generated file.
+#
+# Regenerating this file via `configlet sync` will:
+# - Recreate every `description` key/value pair
+# - Recreate every `reimplements` key/value pair, where they exist in problem-specifications
+# - Remove any `include = true` key/value pair (an omitted `include` key implies inclusion)
+# - Preserve any other key/value pair
+#
+# As user-added comments (using the # character) will be removed when this file
+# is regenerated, comments can be added via a `comment` key.
+
+[ae86ea7d-bd07-4357-90b3-ac7d256bd5c5]
+description = "empty matrix"
+
+[4ea5ccb7-7b73-4281-954a-bed1b0f139a5]
+description = "live cells with zero live neighbors die"
+
+[df245adc-14ff-4f9c-b2ae-f465ef5321b2]
+description = "live cells with only one live neighbor die"
+
+[2a713b56-283c-48c8-adae-1d21306c80ae]
+description = "live cells with two live neighbors stay alive"
+
+[86d5c5a5-ab7b-41a1-8907-c9b3fc5e9dae]
+description = "live cells with three live neighbors stay alive"
+
+[015f60ac-39d8-4c6c-8328-57f334fc9f89]
+description = "dead cells with three live neighbors become alive"
+
+[2ee69c00-9d41-4b8b-89da-5832e735ccf1]
+description = "live cells with four or more neighbors die"
+
+[a79b42be-ed6c-4e27-9206-43da08697ef6]
+description = "bigger matrix"

exercises/practice/game-of-life/game_of_life.moon

@@ -0,0 +1,4 @@
+{
+  tick: (matrix) ->
+    error 'Implement me'
+}

exercises/practice/game-of-life/game_of_life_spec.moon

@@ -0,0 +1,116 @@
+GameOfLife = require 'game_of_life'
+
+describe 'game-of-life', ->
+  it 'empty matrix', ->
+    matrix = {}
+    result = GameOfLife.tick matrix
+    expected = {}
+    assert.are.same expected, result
+
+  pending 'live cells with zero live neighbors die', ->
+    matrix = {
+      {0, 0, 0},
+      {0, 1, 0},
+      {0, 0, 0},
+    }
+    result = GameOfLife.tick matrix
+    expected = {
+      {0, 0, 0},
+      {0, 0, 0},
+      {0, 0, 0},
+    }
+    assert.are.same expected, result
+
+  pending 'live cells with only one live neighbor die', ->
+    matrix = {
+      {0, 0, 0},
+      {0, 1, 0},
+      {0, 1, 0},
+    }
+    result = GameOfLife.tick matrix
+    expected = {
+      {0, 0, 0},
+      {0, 0, 0},
+      {0, 0, 0},
+    }
+    assert.are.same expected, result
+
+  pending 'live cells with two live neighbors stay alive', ->
+    matrix = {
+      {1, 0, 1},
+      {1, 0, 1},
+      {1, 0, 1},
+    }
+    result = GameOfLife.tick matrix
+    expected = {
+      {0, 0, 0},
+      {1, 0, 1},
+      {0, 0, 0},
+    }
+    assert.are.same expected, result
+
+  pending 'live cells with three live neighbors stay alive', ->
+    matrix = {
+      {0, 1, 0},
+      {1, 0, 0},
+      {1, 1, 0},
+    }
+    result = GameOfLife.tick matrix
+    expected = {
+      {0, 0, 0},
+      {1, 0, 0},
+      {1, 1, 0},
+    }
+    assert.are.same expected, result
+
+  pending 'dead cells with three live neighbors become alive', ->
+    matrix = {
+      {1, 1, 0},
+      {0, 0, 0},
+      {1, 0, 0},
+    }
+    result = GameOfLife.tick matrix
+    expected = {
+      {0, 0, 0},
+      {1, 1, 0},
+      {0, 0, 0},
+    }
+    assert.are.same expected, result
+
+  pending 'live cells with four or more neighbors die', ->
+    matrix = {
+      {1, 1, 1},
+      {1, 1, 1},
+      {1, 1, 1},
+    }
+    result = GameOfLife.tick matrix
+    expected = {
+      {1, 0, 1},
+      {0, 0, 0},
+      {1, 0, 1},
+    }
+    assert.are.same expected, result
+
+  pending 'bigger matrix', ->
+    matrix = {
+      {1, 1, 0, 1, 1, 0, 0, 0},
+      {1, 0, 1, 1, 0, 0, 0, 0},
+      {1, 1, 1, 0, 0, 1, 1, 1},
+      {0, 0, 0, 0, 0, 1, 1, 0},
+      {1, 0, 0, 0, 1, 1, 0, 0},
+      {1, 1, 0, 0, 0, 1, 1, 1},
+      {0, 0, 1, 0, 1, 0, 0, 1},
+      {1, 0, 0, 0, 0, 0, 1, 1},
+    }
+    result = GameOfLife.tick matrix
+    expected = {
+      {1, 1, 0, 1, 1, 0, 0, 0},
+      {0, 0, 0, 0, 0, 1, 1, 0},
+      {1, 0, 1, 1, 1, 1, 0, 1},
+      {1, 0, 0, 0, 0, 0, 0, 1},
+      {1, 1, 0, 0, 1, 0, 0, 1},
+      {1, 1, 0, 1, 0, 0, 0, 1},
+      {1, 0, 0, 0, 0, 0, 0, 0},
+      {0, 0, 0, 0, 0, 0, 1, 1},
+    }
+    assert.are.same expected, result