Deep object comparison benchmark

README.md

Requires hyperfine to run: https://github.com/sharkdp/hyperfine

Run it like so: hyperfine 'node dequal.mjs' 'node md5.mjs' 'node sha1.mjs'

Results:

Summary
  'node dequal.mjs' ran
    1.16 ± 0.20 times faster than 'node md5.mjs'
    1.17 ± 0.21 times faster than 'node sha1.mjs'

dequal.mjs

export function deepEquals(foo, bar) {
  let ctor, len;
  if (foo === bar) {
    return true;
  }

  if (foo && bar && (ctor = foo.constructor) === bar.constructor) {
    if (ctor === Array) {
      if ((len = foo.length) === bar.length) {
        while (len-- && deepEquals(foo[len], bar[len])) { }
      }
      return len === -1;
    }

    if (!ctor || typeof foo === 'object') {
      len = 0;
      for (ctor in foo) {
        if (
          Object.prototype.hasOwnProperty.call(foo, ctor) &&
          ++len &&
          !Object.prototype.hasOwnProperty.call(bar, ctor)
        ) {
          return false;
        }
        if (!(ctor in bar) || !deepEquals(foo[ctor], bar[ctor])) {
          return false;
        }
      }
      return Object.keys(bar).length === len;
    }
  }

  return foo !== foo && bar !== bar;
}

const a = {
  prop1: 'value1',
  prop2: 'value2',
  prop3: 'value3',
  prop4: {
    subProp1: 'sub value1',
    subProp2: {
      subSubProp1: 'sub sub value1',
      subSubProp2: [1, 2, { prop2: 1, prop: 2 }, 4, 5],
    },
  },
  prop5: 1000,
  prop6: new Date(2016, 2, 10).getTime(),
};
const b = {
  prop5: 1000,
  prop3: 'value3',
  prop1: 'value1',
  prop2: 'value2',
  prop6: new Date('2016/03/10').getTime(),
  prop4: {
    subProp2: {
      subSubProp1: 'sub sub value1',
      subSubProp2: [1, 2, { prop2: 1, prop: 2 }, 4, 5],
    },
    subProp1: 'sub value1',
  },
};

if (!deepEquals(a, b)) {
  throw new Error();
}

md5.mjs

import crypto from 'crypto'

const a = {
  prop1: 'value1',
  prop2: 'value2',
  prop3: 'value3',
  prop4: {
    subProp1: 'sub value1',
    subProp2: {
      subSubProp1: 'sub sub value1',
      subSubProp2: [1, 2, { prop2: 1, prop: 2 }, 4, 5],
    },
  },
  prop5: 1000,
  prop6: new Date(2016, 2, 10).getTime(),
};

const hashA = crypto.createHash('md5').update(JSON.stringify(a)).digest('base64');
const hashB = crypto.createHash('md5').update(JSON.stringify(a)).digest('base64');
if (hashA !== hashB) {
  throw new Error();
}

sha1.mjs

import crypto from 'crypto'

const a = {
  prop1: 'value1',
  prop2: 'value2',
  prop3: 'value3',
  prop4: {
    subProp1: 'sub value1',
    subProp2: {
      subSubProp1: 'sub sub value1',
      subSubProp2: [1, 2, { prop2: 1, prop: 2 }, 4, 5],
    },
  },
  prop5: 1000,
  prop6: new Date(2016, 2, 10).getTime(),
};

const hashA = crypto.createHash('sha1').update(JSON.stringify(a)).digest('base64');
const hashB = crypto.createHash('sha1').update(JSON.stringify(a)).digest('base64');
if (hashA !== hashB) {
  throw new Error();
}