Regarding expected result of average(req, next)

[veshboo]

I wrote a test for function average(req, next).
What is the expected req.value for the 2nd duration average?

{sensorjs-root-dir}/test/test-2nd-average.js

'use strict';
const assert = require('assert');
const average = require('../lib/middleware/average')(1.5); // duration 1.5 sec

const v = [1.0, // t: 100
           0.0, // t: 200
           2.0, // t: 2000, average (ac, ex) = (0.5, 0.5)
           4.0, // t: 2100
           3.0  // t: 4000, average (ac, ex) = (4.0, 3.0)
          ];
const req = {};

const next = function () {};
const check1 = function () {
  console.log(`1st average=${req.value}`);
  assert.strictEqual(req.value, 0.5, 'fail on average 1nd duration');
}
const check2 = function () {
  console.log(`2nd average=${req.value}`);
  assert.strictEqual(req.value, 3.0, 'fail on average 2nd duration'); // XXX
}

setTimeout(() => {req.value = v[0]; average(req, next);}, 100);
setTimeout(() => {req.value = v[1]; average(req, next);}, 200);
setTimeout(() => {req.value = v[2]; average(req, check1);}, 2000); // 1st
setTimeout(() => {req.value = v[3]; average(req, next);}, 2000 + 100);
setTimeout(() => {req.value = v[4]; average(req, check2);}, 2000 + 2000); // 2nd

# cd {sensor-js-root-dir}
node test/test-2nd-average.js