String concat vs pass string reference

JavaScript performance comparison

Test case created by Gleb Bahmutov

Preparation code

Benchmark.prototype.setup = function() {
  function assertionMock(condition, msg1, msg2) {
    return true;


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Testing in CCBot 2.0.0 / Other 0.0.0
Test Ops/sec
concatenate 2 strings
assertionMock(true, 'foo ' + 'bar');
pass 2 separate strings
assertionMock(true, 'foo ', 'bar');

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