Benchmark of "uniq" for Array in JavaScript

array-uniq-benchmark.js

// License: MIT
// Original Author: YUKI "Piro" Hiroshi <[email protected]>

// confirmed at Firefox 64

async function test(times, length) {
  function uniqByIndexOf(array) {
    const uniquedArray = [];
    for (const elem of array) {
      if (uniquedArray.indexOf(elem) < 0)
        uniquedArray.push(elem);
    }
    return uniquedArray;
  }

  function uniqByIncludes(array) {
    const uniquedArray = [];
    for (const elem of array) {
      if (!uniquedArray.includes(elem))
        uniquedArray.push(elem);
    }
    return uniquedArray;
  }

  function uniqByFilter(array) {
    return array.filter(function(elem, index, self) {
      return self.indexOf(elem) === index;
    });
  }

  function uniqByFilterArrow(array) {
    return array.filter((elem, index, self) => self.indexOf(elem) === index);
  }

  function uniqByMap(array) {
    const knownElements = new Map();
    const uniquedArray = [];
    for (const elem of array) {
      if (knownElements.has(elem))
        continue;
      uniquedArray.push(elem);
      knownElements.set(elem, true);
    }
    return uniquedArray;
  }

  function uniqByMapKeys(array) {
    const knownElements = new Map();
    for (const elem of array) {
      knownElements.set(elem, true);
    }
    return Array.from(knownElements.keys());
  }

  function uniqBySet(array) {
    return Array.from(new Set(array));
  }

  function uniqBySetAndSpread(array) {
    return [...new Set(array)];
  }

  function prepareArray(length) {
    const array = [];
    for (let i = 0; i < length; i++) {
      array.push(parseInt(Math.random() * (length / 10)));
    }
    return array;
  }

  const methods = [uniqByIndexOf, uniqByIncludes, uniqByFilter, uniqByFilterArrow, uniqByMap, uniqByMapKeys, uniqBySet, uniqBySetAndSpread];
  const results = [];
  for (const uniq of methods) {
    const start = Date.now();
    const array = prepareArray(length);
    for (let i = 0; i < times; i++) {
      uniq(Array.from(array));
    }
    const delta = Date.now() - start;
    console.log(`${times}times, length=${length}, ${uniq.name}`, delta);
    results.push(delta);
    await new Promise(resolve => setTimeout(resolve, 10));
  }
  return results;
}

(async () => {
  const methods = ',uniqByIndexOf,uniqByIncludes,uniqByFilter,uniqByFilterArrow,uniqByMap,uniqByMapKeys,uniqBySet,uniqBySetAndSpread';

  async function runForTimes(length, start, step) {
    const results = [methods];
    for (let i = 0, maxi = 5; i < maxi; i++) {
      const times = start + (step * i);
      results.push(times + ',' + (await test(times, length)).join(','));
    }
    console.log(results.join('\n'));
  }

  console.log('tests with small array');
  await runForTimes(10, 100000, 100000);
  console.log('tests with middle array');
  await runForTimes(300, 2500, 2500);
  console.log('tests with large array');
  await runForTimes(5000, 100, 100);

  async function runForLength(times, start, step) {
    const results = [methods];
    for (let i = 0, maxi = 10; i < maxi; i++) {
      const length = start + (step * i);
      results.push(length + ',' + (await test(times, length)).join(','));
    }
    console.log(results.join('\n'));
  }
  console.log('tests with increasing length');
  await runForLength(5000, 100, 100);

  console.log('done');
})();

increasing-length-on-nightly.csv

increasing-length.csv

large-array.csv

middle-array.csv

small-array.csv

graph: