ES6 Generator testing

index.js

function getData(callback) {
  setTimeout(function() {
    callback(null, Date.now());
  }, 1000);
}

function asyncCallback(generator) {
  return function() {
    var resolve = function(gen, data) {
      var next = gen.next(data);
      var fn = next.value;

      if (next.done) return;

      fn(function(err, data) {
        resolve(gen, data);
      });
    };
    resolve(generator());
  };
}

var fn = asyncCallback(function* () {
  var time = yield getData;
  console.log(time);
  var time2 = yield getData;
  console.log(time2);
});

fn();