underscore-memoize-perf.js

'use strict'

const _ = require('./underscore')
const Benchmark = require('benchmark')
const debug = require('logdown')()

// Current

function fibonacci(n) {
    return n < 2 ? n : fibonacci(n - 1) + fibonacci(n - 2)
}

fibonacci = _.memoizeOriginal(fibonacci)

// Improved

function fibonacci2(n) {
    return n < 2 ? n : fibonacci2(n - 1) + fibonacci2(n - 2)
}

fibonacci2 = _.memoize(fibonacci2)

// Benchmark suite

let suiteFibonnaci = new Benchmark.Suite()
let fibNumber = 15

suiteFibonnaci
  .add('current', () => {
    fibonacci(fibNumber)
  })
  .add('improved', () => {
    fibonacci2(fibNumber)
  })
  .on('cycle', (event) => {
    const currentRunning = String(event.target)
      .replace(/(.*)\ x/, (match, p1) => `\`${p1}\` x`)
    debug.log(currentRunning)
  })
  .on('complete', function () {
    debug.log()
    debug.log(`Fastest is \`${this.filter('fastest').map('name')}\``)
  })
  .run({'async': true})