EventLoop 解析 ​

console.log(1) 

async function fn1() {
  console.log(2)
  await fn2()
  console.log(3) 
  return 4
}

fn1().then(fn4)
  .then((res) => {
      console.log(res) 
  })
  
fn3().then((res) => {
  console.log(res)
})

async function fn2() {
  console.log(5)
  setTimeout(() => {
    console.log(6)
  })
}

function fn3() {
  console.log(7)
  return new Promise((resolve, reject) => {
    console.log(8)
   
    setTimeout(() => {
      resolve(9) 
    })
  })
}

function fn4(num) {
  console.log(num)
  return new Promise((resolve, reject) => {
    console.log(10)
    resolve(11)
  })
}