vm-iife-performance.js

'use strict';
// https://60devs.com/executing-js-code-with-nodes-vm-module.html

var code = `
// global script scope
function nop() {
};
var i = 1000000; // global script scope
while (i--) {
  nop(); // access global scope
}
console.log('done');
`;

console.time('eval');
eval(code);
console.timeEnd('eval');

var vm = require('vm');
var context = vm.createContext({ console });
var script = new vm.Script(code);

console.time('vm');
script.runInContext(context);
console.timeEnd('vm');

var context = vm.createContext({ console });
var script = new vm.Script(`(function() { ${code} })()`);

console.time('iife vm');
script.runInContext(context);
console.timeEnd('iife vm');