JavaScript Await Async

Async Await in JavaScript

'use strict'

const delay = (time) => new Promise((resolve, reject) => setTimeout(resolve, time));

async function start1() {
  bar(); // Add a `await` before `bar()` to see what will happen.
  foo();
}

function foo() {
  console.log("==== start foo() ====");
  setTimeout(() => console.log("timeout in foo()"), 5000);
  console.log("==== end foo() ====");
}

async function bar() {
  console.log("==== start bar() ====");
  await delay(3000);
  console.log("==== end bar() ====");
}

start1();

For the above code, guess what it will print?

'use strict'

const delay = (time) => new Promise((resolve, reject) => setTimeout(resolve, time));

async function start1() {
  bar(); // Add a `await` before `bar()` to see what will happen.
  foo();
}

function foo() {
  console.log("==== start foo() ====");
  setTimeout(() => console.log("timeout in foo()"), 5000);
  console.log("==== end foo() ====");
}

async function bar() {
  console.log("==== start bar() ====");
  await delay(3000);
  console.log("==== end bar() ====");
}

start1();

Actually, await delay(3000); will block the next line console.log("==== end bar() ====");, but it will not block foo() unless it is await bar();.