New exercise ✨: DnD Character

config.json

@@ -90,6 +90,15 @@
         "difficulty": 2,
         "topics": ["classes", "floating_point_numbers"]
       },
+      {
+        "slug": "dnd-character",
+        "name": "DnD Character",
+        "uuid": "6f34eb4d-4028-4f89-9965-c9a887f416a0",
+        "practices": [],
+        "prerequisites": [],
+        "difficulty": 2,
+        "topics": ["classes"]
+      },
       {
         "slug": "pangram",
         "name": "Pangram",

exercises/practice/dnd-character/.docs/instructions.md

@@ -0,0 +1,33 @@
+# Description
+
+For a game of [Dungeons & Dragons][dnd], each player starts by generating a
+character they can play with. This character has, among other things, six
+abilities; strength, dexterity, constitution, intelligence, wisdom and
+charisma. These six abilities have scores that are determined randomly. You
+do this by rolling four 6-sided dice and record the sum of the largest three
+dice. You do this six times, once for each ability.
+
+Your character's initial hitpoints are 10 + your character's constitution
+modifier. You find your character's constitution modifier by subtracting 10
+from your character's constitution, divide by 2 and round down.
+
+Write a random character generator that follows the rules above.
+
+For example, the six throws of four dice may look like:
+
+- 5, 3, 1, 6: You discard the 1 and sum 5 + 3 + 6 = 14, which you assign to strength.
+- 3, 2, 5, 3: You discard the 2 and sum 3 + 5 + 3 = 11, which you assign to dexterity.
+- 1, 1, 1, 1: You discard the 1 and sum 1 + 1 + 1 = 3, which you assign to constitution.
+- 2, 1, 6, 6: You discard the 1 and sum 2 + 6 + 6 = 14, which you assign to intelligence.
+- 3, 5, 3, 4: You discard the 3 and sum 5 + 3 + 4 = 12, which you assign to wisdom.
+- 6, 6, 6, 6: You discard the 6 and sum 6 + 6 + 6 = 18, which you assign to charisma.
+
+Because constitution is 3, the constitution modifier is -4 and the hitpoints are 6.
+
+## Notes
+
+Most programming languages feature (pseudo-)random generators, but few
+programming languages are designed to roll dice. One such language is [Troll].
+
+[dnd]: https://en.wikipedia.org/wiki/Dungeons_%26_Dragons
+[troll]: http://hjemmesider.diku.dk/~torbenm/Troll/

exercises/practice/dnd-character/.eslintignore

@@ -0,0 +1,12 @@
+!.meta
+
+# Protected or generated
+.git
+.vscode
+
+# When using npm
+node_modules/*
+
+# Configuration files
+babel.config.js
+jest.config.js

exercises/practice/dnd-character/.eslintrc

@@ -0,0 +1,23 @@
+{
+  "root": true,
+  "parser": "@typescript-eslint/parser",
+  "parserOptions": {
+    "project": "./tsconfig.json",
+    "ecmaFeatures": {
+      "jsx": true
+    },
+    "ecmaVersion": 2020,
+    "sourceType": "module"
+  },
+  "extends": "@exercism/eslint-config-typescript",
+  "env": {
+    "jest": true
+  },
+  "overrides": [
+    {
+      "files": [".meta/proof.ci.ts", ".meta/exemplar.ts", "*.test.ts"],
+      "excludedFiles": ["custom.test.ts"],
+      "extends": "@exercism/eslint-config-typescript/maintainers"
+    }
+  ]
+}

exercises/practice/dnd-character/.meta/config.json

@@ -0,0 +1,12 @@
+{
+  "blurb": "Randomly generate Dungeons & Dragons characters.",
+  "authors": ["JoshiRaez", "SleeplessByte"],
+  "contributors": [],
+  "files": {
+    "solution": ["dnd-character.ts"],
+    "test": ["dnd-character.test.ts"],
+    "example": [".meta/proof.ci.ts"]
+  },
+  "source": "Simon Shine, Erik Schierboom",
+  "source_url": "https://github.com/exercism/problem-specifications/issues/616#issuecomment-437358945"
+}

exercises/practice/dnd-character/.meta/proof.ci.ts

@@ -0,0 +1,40 @@
+export class DnDCharacter {
+  public readonly hitpoints: number
+
+  public readonly strength: number
+  public readonly dexterity: number
+  public readonly constitution: number
+  public readonly intelligence: number
+  public readonly wisdom: number
+  public readonly charisma: number
+
+  constructor() {
+    this.strength = DnDCharacter.generateAbilityScore()
+    this.dexterity = DnDCharacter.generateAbilityScore()
+    this.constitution = DnDCharacter.generateAbilityScore()
+    this.intelligence = DnDCharacter.generateAbilityScore()
+    this.wisdom = DnDCharacter.generateAbilityScore()
+    this.charisma = DnDCharacter.generateAbilityScore()
+
+    this.hitpoints = 10 + DnDCharacter.getModifierFor(this.constitution)
+  }
+
+  public static generateAbilityScore(): number {
+    return this.rollDice(4)
+      .sort()
+      .slice(1, 4)
+      .reduce((acu, act) => acu + act, 0)
+  }
+
+  public static getModifierFor(abilityValue: number): number {
+    return Math.floor((abilityValue - 10) / 2)
+  }
+
+  private static rollDice(quantity: number): number[] {
+    return new Array<number>(quantity).fill(0).map(() => this.rollDie())
+  }
+
+  private static rollDie(): number {
+    return Math.floor(Math.random() * 6) + 1
+  }
+}

exercises/practice/dnd-character/.meta/tests.toml

@@ -0,0 +1,76 @@
+[1e9ae1dc-35bd-43ba-aa08-e4b94c20fa37]
+description = "Ability modifier for score 3 is -4"
+include = true
+
+[cc9bb24e-56b8-4e9e-989d-a0d1a29ebb9c]
+description = "Ability modifier for score 4 is -3"
+include = true
+
+[5b519fcd-6946-41ee-91fe-34b4f9808326]
+description = "Ability modifier for score 5 is -3"
+include = true
+
+[dc2913bd-6d7a-402e-b1e2-6d568b1cbe21]
+description = "Ability modifier for score 6 is -2"
+include = true
+
+[099440f5-0d66-4b1a-8a10-8f3a03cc499f]
+description = "Ability modifier for score 7 is -2"
+include = true
+
+[cfda6e5c-3489-42f0-b22b-4acb47084df0]
+description = "Ability modifier for score 8 is -1"
+include = true
+
+[c70f0507-fa7e-4228-8463-858bfbba1754]
+description = "Ability modifier for score 9 is -1"
+include = true
+
+[6f4e6c88-1cd9-46a0-92b8-db4a99b372f7]
+description = "Ability modifier for score 10 is 0"
+include = true
+
+[e00d9e5c-63c8-413f-879d-cd9be9697097]
+description = "Ability modifier for score 11 is 0"
+include = true
+
+[eea06f3c-8de0-45e7-9d9d-b8cab4179715]
+description = "Ability modifier for score 12 is 1"
+include = true
+
+[9c51f6be-db72-4af7-92ac-b293a02c0dcd]
+description = "Ability modifier for score 13 is 1"
+include = true
+
+[94053a5d-53b6-4efc-b669-a8b5098f7762]
+description = "Ability modifier for score 14 is 2"
+include = true
+
+[8c33e7ca-3f9f-4820-8ab3-65f2c9e2f0e2]
+description = "Ability modifier for score 15 is 2"
+include = true
+
+[c3ec871e-1791-44d0-b3cc-77e5fb4cd33d]
+description = "Ability modifier for score 16 is 3"
+include = true
+
+[3d053cee-2888-4616-b9fd-602a3b1efff4]
+description = "Ability modifier for score 17 is 3"
+include = true
+
+[bafd997a-e852-4e56-9f65-14b60261faee]
+description = "Ability modifier for score 18 is 4"
+include = true
+
+[4f28f19c-2e47-4453-a46a-c0d365259c14]
+description = "Random ability is within range"
+include = true
+
+[385d7e72-864f-4e88-8279-81a7d75b04ad]
+description = "Random character is valid"
+include = true
+
+[2ca77b9b-c099-46c3-a02c-0d0f68ffa0fe]
+description = "Each ability is only calculated once"
+include = true
+

exercises/practice/dnd-character/babel.config.js

@@ -0,0 +1,20 @@
+module.exports = {
+  presets: [
+    [
+      '@babel/preset-env',
+      {
+        targets: {
+          node: 'current',
+        },
+        useBuiltIns: 'entry',
+        corejs: '3.17',
+      },
+    ],
+    '@babel/preset-typescript',
+  ],
+  plugins: [
+    '@babel/proposal-class-properties',
+    '@babel/proposal-object-rest-spread',
+    '@babel/plugin-syntax-bigint',
+  ],
+}

exercises/practice/dnd-character/dnd-character.test.ts

@@ -0,0 +1,109 @@
+import { DnDCharacter } from './dnd-character'
+
+describe('Ability modifier', () => {
+  test('Ability modifier for score 3 is -4', () => {
+    expect(DnDCharacter.getModifierFor(3)).toEqual(-4)
+  })
+
+  test('Ability modifier for score 4 is -3', () => {
+    expect(DnDCharacter.getModifierFor(4)).toEqual(-3)
+  })
+
+  test('Ability modifier for score 5 is -3', () => {
+    expect(DnDCharacter.getModifierFor(5)).toEqual(-3)
+  })
+
+  test('Ability modifier for score 6 is -2', () => {
+    expect(DnDCharacter.getModifierFor(6)).toEqual(-2)
+  })
+
+  test('Ability modifier for score 7 is -2', () => {
+    expect(DnDCharacter.getModifierFor(7)).toEqual(-2)
+  })
+
+  test('Ability modifier for score 8 is -1', () => {
+    expect(DnDCharacter.getModifierFor(8)).toEqual(-1)
+  })
+
+  test('Ability modifier for score 9 is -1', () => {
+    expect(DnDCharacter.getModifierFor(9)).toEqual(-1)
+  })
+
+  test('Ability modifier for score 10 is 0', () => {
+    expect(DnDCharacter.getModifierFor(10)).toEqual(0)
+  })
+
+  test('Ability modifier for score 11 is 0', () => {
+    expect(DnDCharacter.getModifierFor(11)).toEqual(0)
+  })
+
+  test('Ability modifier for score 12 is 1', () => {
+    expect(DnDCharacter.getModifierFor(12)).toEqual(1)
+  })
+
+  test('Ability modifier for score 13 is 1', () => {
+    expect(DnDCharacter.getModifierFor(13)).toEqual(1)
+  })
+
+  test('Ability modifier for score 14 is 2', () => {
+    expect(DnDCharacter.getModifierFor(14)).toEqual(2)
+  })
+
+  test('Ability modifier for score 15 is 2', () => {
+    expect(DnDCharacter.getModifierFor(15)).toEqual(2)
+  })
+
+  test('Ability modifier for score 16 is 3', () => {
+    expect(DnDCharacter.getModifierFor(16)).toEqual(3)
+  })
+
+  test('Ability modifier for score 17 is 3', () => {
+    expect(DnDCharacter.getModifierFor(17)).toEqual(3)
+  })
+
+  test('Ability modifier for score 18 is 4', () => {
+    expect(DnDCharacter.getModifierFor(18)).toEqual(4)
+  })
+})
+
+describe('Ability generator', () => {
+  test('Random ability is within range', () => {
+    const abilityScore = DnDCharacter.generateAbilityScore()
+    expect(abilityScore).toBeGreaterThanOrEqual(3)
+    expect(abilityScore).toBeLessThanOrEqual(18)
+  })
+})
+
+describe('Character creation', () => {
+  test('Random character is valid', () => {
+    const character = new DnDCharacter()
+
+    expect(character.hitpoints).toEqual(
+      10 + DnDCharacter.getModifierFor(character.constitution)
+    )
+
+    expect(character.strength).toBeGreaterThanOrEqual(3)
+    expect(character.strength).toBeLessThanOrEqual(18)
+
+    expect(character.dexterity).toBeGreaterThanOrEqual(3)
+    expect(character.dexterity).toBeLessThanOrEqual(18)
+
+    expect(character.constitution).toBeGreaterThanOrEqual(3)
+    expect(character.constitution).toBeLessThanOrEqual(18)
+
+    expect(character.intelligence).toBeGreaterThanOrEqual(3)
+    expect(character.intelligence).toBeLessThanOrEqual(18)
+
+    expect(character.wisdom).toBeGreaterThanOrEqual(3)
+    expect(character.wisdom).toBeLessThanOrEqual(18)
+
+    expect(character.charisma).toBeGreaterThanOrEqual(3)
+    expect(character.charisma).toBeLessThanOrEqual(18)
+  })
+
+  test('Each ability is only calculated once', () => {
+    const character = new DnDCharacter()
+
+    expect(character.strength === character.strength).toBeTruthy()
+  })
+})

exercises/practice/dnd-character/dnd-character.ts

@@ -0,0 +1,9 @@
+export class DnDCharacter {
+  public static generateAbilityScore(): number {
+    throw new Error('Remove this statement and implement this function')
+  }
+
+  public static getModifierFor(abilityValue: number): number {
+    throw new Error('Remove this statement and implement this function')
+  }
+}

exercises/practice/dnd-character/jest.config.js

@@ -0,0 +1,19 @@
+module.exports = {
+  verbose: true,
+  projects: ['<rootDir>'],
+  testMatch: [
+    '**/__tests__/**/*.[jt]s?(x)',
+    '**/test/**/*.[jt]s?(x)',
+    '**/?(*.)+(spec|test).[jt]s?(x)',
+  ],
+  testPathIgnorePatterns: [
+    '/(?:production_)?node_modules/',
+    '.d.ts$',
+    '<rootDir>/test/fixtures',
+    '<rootDir>/test/helpers',
+    '__mocks__',
+  ],
+  transform: {
+    '^.+\\.[jt]sx?$': 'babel-jest',
+  },
+}