async-iterations.js

(async () => {
  const waitFor = (ms) => new Promise(r => setTimeout(r, ms));
  const array = [1, 2, 3];
  const obj = {a: 1, b: 2, c: 3};

  for (let index = 0; index < array.length; index++) { // passes
    await waitFor(50);
    console.log('for-let:', array[index]);
  }
  console.log('for-let done ---PASSES---');

  array.forEach(async n => { // fails
    await waitFor(50);
    console.log('forEach', n);
  });
  console.log('forEach done ---FAILS---');

  for (const n of array) { // passes
    await waitFor(50);
    console.log('for of', n)
  }
  console.log('for of done ---PASSES---');

  await Promise.all(array.map(n => { // passes
    waitFor(50);
    console.log('Promise.all', n);
  }));
  console.log('Promise.all done ---PASSES---')

  for (const prop in obj) { // passes
    await waitFor(50);
    console.log('for in', obj[prop]);
  }
  console.log('for in done ---PASSES---');
})();