编辑代码

console.log('script start---1') //同步

async function async1() {
  await async2()
  console.log('async1 end---5')
}
async function async2() {
  console.log('async2 end---2')
}
async1()

setTimeout(function() {
  console.log('setTimeout---8')
}, 0)

new Promise(resolve => {
  console.log('Promise---3')
  resolve()
})
  .then(function() {
    console.log('promise1---6')
  })
  .then(function() {
    console.log('promise2---7')
  })

console.log('script end---4')