test_env.js

var process_copy = Object.assign({}, process);
var process_ref = process;
process_copy.env = Object.assign({}, process.env);
var lab1 = 'normal process.env';
var lab2 = 'process copy env';
console.time(lab1);
var no_discard = false;

for(var i = 0; i < 1e7; i++) {
   no_discard = no_discard || (process_ref.env.NODE_ENV == Math.random());
}

console.timeEnd(lab1);

console.time(lab2)
for(var i = 0; i < 1e7; i++) {
   no_discard = no_discard || (process_copy.env.NODE_ENV == Math.random());
}

console.timeEnd(lab2);