test.js

/* jshint esversion: 6, node: true, mocha: true */
const dice = require('./dice.js');
const prng = require('seedrandom')('hello');
const assert = require('assert');

describe('Dice()', function () {
    it('should roll the indicated die from notation', function () {
        assert.strictEqual(4, dice('1d6', prng));
    });
    it('should roll the indicated die from numbers', function () {
        assert.strictEqual(3, dice(1, 6, prng));
    });
    it('should roll the indicated die an indicated number of times from notation', function () {
        assert.strictEqual(12, dice('3d6', prng));
    });
    it('should roll the indicated die an indicated number of times from numbers', function () {
        assert.strictEqual(17, dice(3, 6, prng));
    });
    it('should accept modifiers', function () {
        assert.strictEqual(15, dice('3d6+2', prng));
    });
    it('should use Math.random() when no random function is provided', function () {
        assert.ok(dice('1d6') < 7);
    });
    it('should compress and trim excess spaces', function () {
        assert.ok(dice('1 d 6 + 1') <= 7);
        assert.ok(dice('1d6 + 1') <= 7);
        assert.ok(dice(' 1d6 ') < 7);
    });
    it('should throw on bad constructions', function () {
        assert.throws(() => dice('0d6'));
        assert.throws(() => dice('1d0'));
        assert.throws(() => dice('Fd6'));
        assert.throws(() => dice('1d'));
        assert.throws(() => dice('hi'));
        assert.throws(() => dice(0, 6));
        assert.throws(() => dice(1, 0));
        assert.throws(() => dice(1));
        assert.throws(() => dice(null));
        assert.throws(() => dice('hello', 6));
    });
});

describe('Dice.detailed()', function () {
    it('should create accurate, detailed rolls', function () {
        var detailed = dice.detailed('3d6 + 10', prng);
        assert.strictEqual(3, detailed.rolls.length);
        assert.strictEqual(3, detailed.number);
        assert.strictEqual(10, detailed.modifier);
        assert.strictEqual(19, detailed.result);
    });
    it('should output a valid object', function () {
        var detailed = dice.detailed('1d4', prng);
        assert.strictEqual("object", typeof detailed);
        assert.strictEqual('{"number":1,"type":4,"modifier":0,"rolls":[3],"result":3}', JSON.stringify(detailed));
    });
});

describe('Dice.parse()', function () {
    const parse = dice.parse('3d6');
    const parsePos = dice.parse('3d6+2');
    const parseNeg = dice.parse('3d6-2');
    const parseMultDigit = dice.parse('200d70+5000');
    const parseUpperCase = dice.parse('3D6');
    it('should parse valid dice notation', function () {
        assert.strictEqual(3, parse.number);
        assert.strictEqual(6, parse.type);
        assert.strictEqual(0, parse.modifier);
    });
    it('should parse valid dice notation with positive modifiers', function () {
        assert.strictEqual(3, parsePos.number);
        assert.strictEqual(6, parsePos.type);
        assert.strictEqual(2, parsePos.modifier);
    });
    it('should parse valid dice notation with negative modifiers', function () {
        assert.strictEqual(3, parseNeg.number);
        assert.strictEqual(6, parseNeg.type);
        assert.strictEqual(-2, parseNeg.modifier);
    });
    it('should parse multiple-digit numbers accurately', function () {
        assert.strictEqual(200, parseMultDigit.number);
        assert.strictEqual(70, parseMultDigit.type);
        assert.strictEqual(5000, parseMultDigit.modifier);
    });
    it('should parse with a capital "D" as well as with a lower case "d"', function () {
        assert.strictEqual(3, parseUpperCase.number);
        assert.strictEqual(6, parseUpperCase.type);
        assert.strictEqual(0, parseUpperCase.modifier);
    });

    // whoopsie
    it('should work with 2-digit numbers', function () {
        assert.strictEqual(76, dice('10d12', prng));
    });
});