Run results for: for in vs foreach

Run details:

User agent: Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/85.0.4183.121 Safari/537.36

Browser: Chrome 85

Operating system: Linux

Device Platform: Desktop

Date tested: 4 years ago

Test name	Executions per second
omit for 3 keys	3025290.8 Ops/sec
foreach for 3 keys	3206463.2 Ops/sec
omit for 2 keys	2924220.0 Ops/sec
forEach for 2 keys	3819694.2 Ops/sec

HTML Preparation code:

<script src='https://cdnjs.cloudflare.com/ajax/libs/lodash.js/4.17.15/lodash.min.js'></script>

Script Preparation code:

var allHeaders = {
  'Accept-Encoding': 'gzip,deflate',
  'Accept-Language': 'en-US',
  'Content-Type': 'application/json',
  'User-Agent': `(compatible; Mozilla/5.0; MSIE 9.0; Trident/5.0;})`,
  'Proxy-Connection': 'Keep-Alive',
  Connection: 'Keep-Alive',
  Accept: 'application/hal+json, application/json',
};

function omit(obj, keys) {
  var result = {};
  for (let i in obj) {
    if (keys.indexOf(i) >= 0) continue;
    result[i] = obj[i];
  }
  return result;
}

function forEach(obj, keys) {
  var result = {};
  keys.forEach(k => {
  	if (obj[k]) {
      result[k] = obj[k];
    }
  });
  return result;
}

Tests:

omit for 3 keys
omit(allHeaders, ['Accept-Encoding', 'User-Agent', 'Connection']);
foreach for 3 keys
forEach(allHeaders, ['Accept-Encoding', 'User-Agent', 'Connection']);
omit for 2 keys
omit(allHeaders, ['Accept-Encoding', 'Connection']);
forEach for 2 keys
forEach(allHeaders, ['Accept-Encoding', 'Connection']);

Run results for: for in vs foreach

omit for 3 keys

foreach for 3 keys

omit for 2 keys

forEach for 2 keys