Deep Copy vs JSON Stringify / JSON Parse

JavaScript performance comparison

Revision 87 of this test case created by Jonathan Perry

Preparation code

Benchmark.prototype.setup = function() {
  function deepCopy(o) {
       *  Assume that `reduce` is slow, for now
      if (Array.isArray(o)) return o.reduce((a, c) => a.concat(deepCopy(c)), [])
      if ((o || false) instanceof Object) {
          const r = {}
          for (k in o) {
              const c = o[k];
              r[k] = deepCopy(c);
          return r;
      return o;
  var uc = {bir:{iki:{uc:3}}}


Test runner

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Testing in CCBot 2.0.0 / Other 0.0.0
Test Ops/sec
Deep Copy
var bes = deepCopy(uc)
JSON Stringify / JSON Parse
var bes = JSON.parse(JSON.stringify(uc))

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