Run results for: uniqBy vs filter+set

Run details:

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_4) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/93.0.4577.82 Safari/537.36

Browser: Chrome 93

Operating system: Mac OS X 10.15.4

Device Platform: Desktop

Date tested: 3 years ago

Test name	Executions per second
lodash/uniqBy	143538.4 Ops/sec
filter+set	258639.2 Ops/sec

HTML Preparation code:


<script src='https://cdnjs.cloudflare.com/ajax/libs/lodash.js/4.17.5/lodash.min.js'></script>

Script Preparation code:

var smalldata = [1,2,3,4,5,'ok','abc','def',null,undefined,1,2,3,'ok'];
var bigdata = [1,2,3,4,5,'ok','abc','def',null,undefined,1,2,3,'ok',1,2,3,4,5,'ok','abc','def',null,undefined,1,2,3,'ok',1,2,3,4,5,'ok','abc','def',null,undefined,1,2,3,'ok',1,2,3,4,5,'ok','abc','def',null,undefined,1,2,3,'ok',1,2,3,4,5,'ok','abc','def',null,undefined,1,2,3,'ok',1,2,3,4,5,'ok','abc','def',null,undefined,1,2,3,'ok',1,2,3,4,5,'ok','abc','def',null,undefined,1,2,3,'ok',1,2,3,4,5,'ok','abc','def',null,undefined,1,2,3,'ok',1,2,3,4,5,'ok','abc','def',null,undefined,1,2,3,'ok'];

var uniqBy = (arr, fn) => {
  var dups = new Set();
  return arr.filter((v) => {
    const k = fn(v);
    if (dups.has(k)) {
      return false;
    }
    dups.add(k);
    return true;
  });
};

Tests:

lodash/uniqBy
_.uniqBy(smalldata, (v) => v); _.uniqBy(bigdata, (v) => v);
filter+set
uniqBy(smalldata, (v) => v); uniqBy(bigdata, (v) => v);

Run results for: uniqBy vs filter+set

lodash/uniqBy

filter+set