splice-impl-benchmarks.js

'use strict';


function spliceOne(array, index) {
  var newLength = array.length - 1;
  for (var i = index; i < newLength; ++i) {
    array[i] = array[i + 1];
  }
  array.length = newLength;
}


function spliceOneOld(array, index) {
  for (var k = index + 1, n = array.length; k < n; index += 1, k += 1) {
    array[index] = array[k];
  }
  array.pop();
}


function runSplice(arr, index) {
  for (var i = 0; i < 1e7; i++) {
    arr.splice(index, 1);
    arr.push(100);
  }
}


function runSpliceOne(arr, index) {
  for (var i = 0; i < 1e7; i++) {
    spliceOne(arr, index);
    arr.push(100);
  }
}


function runSpliceOneOld(arr, index) {
  for (var i = 0; i < 1e7; i++) {
    spliceOneOld(arr, index);
    arr.push(100);
  }
}


(function runner(fns) {
  if (fns.length === 0)
    return;

  var fn = fns.pop();
  var arr = new Array(150);

  for (var i = 0; i < arr.length; ++i) {
    arr[i] = i;
  }

  var t = process.hrtime();

  fn(arr, 5);

  t = process.hrtime(t);
  console.log(fn.name + ': ', ((t[0] * 1e9 + t[1]) / 1e7).toFixed(1));

  setImmediate(runner, fns);

}([runSplice, runSpliceOne, runSpliceOneOld]));