Improve random number array generation
[benchmarks-js.git] / benchmark-utils.js
1 const crypto = require('crypto')
2
3 /**
4 * Generate a cryptographically secure random number in the [0,1[ range
5 *
6 * @returns
7 */
8 function secureRandom () {
9 return crypto.randomBytes(4).readUInt32LE() / 0x100000000
10 }
11
12 /**
13 * @param max
14 * @param min
15 * @returns
16 */
17 function generateRandomInteger (max = Number.MAX_SAFE_INTEGER, min = 0) {
18 if (max < 0) {
19 throw new RangeError('Invalid interval')
20 }
21 max = Math.floor(max)
22 if (min != null && min !== 0) {
23 if (max < min || min < 0) {
24 throw new RangeError('Invalid interval')
25 }
26 min = Math.ceil(min)
27 return Math.floor(secureRandom() * (max - min + 1)) + min
28 }
29 return Math.floor(secureRandom() * (max + 1))
30 }
31
32 /**
33 *
34 * @param size
35 * @param max
36 * @param numberGenerator
37 */
38 function generateRandomNumberArray (
39 size,
40 max = Number.MAX_VALUE,
41 numberGenerator = generateRandomFloat
42 ) {
43 const array = []
44 for (let i = 0; i < size; i++) {
45 array.push(numberGenerator(max))
46 }
47 return array
48 }
49
50 /**
51 *
52 * @param max
53 * @param min
54 * @param negative
55 */
56 function generateRandomFloat (max = Number.MAX_VALUE, min = 0, negative = true) {
57 if (max < min || min < 0 || max < 0) {
58 throw new RangeError('Invalid interval')
59 }
60 const randomPositiveFloat = crypto.randomBytes(4).readUInt32LE() / 0xffffffff
61 const sign = negative && randomPositiveFloat < 0.5 ? -1 : 1
62 return sign * (randomPositiveFloat * (max - min) + min)
63 }
64
65 /**
66 * @param ms
67 * @returns
68 */
69 async function sleep (ms) {
70 return new Promise(resolve => setTimeout(resolve, ms))
71 }
72
73 const LIST_FORMATTER = new Intl.ListFormat('en-US', {
74 style: 'long',
75 type: 'conjunction'
76 })
77
78 module.exports = {
79 generateRandomInteger,
80 generateRandomFloat,
81 generateRandomNumberArray,
82 sleep,
83 secureRandom,
84 LIST_FORMATTER
85 }