1.txt

outer tick0
inner tick0
outer tick1
After promise.resolve
outer tick2
outer tick3
inner tick1
outer tick4

2.js

new Promise((resolve, reject) => {
  resolve();
})
  .then(() => {
    console.log('outer tick0');
    new Promise((resolve, reject) => {
      resolve();
    })
      .then(() => {
        console.log('inner tick0');
        const r = Promise.resolve();
        r.then(() => {
         console.log('After promise.resolve')
        });
        return r;
      })
      .then(() => {
        console.log('inner tick1');
      })
  })
  .then(() => {
    console.log('outer tick1');
  })
  .then(() => {
    console.log('outer tick2');
  })
  .then(() => {
    console.log('outer tick3');
  })
  .then(() => {
    console.log('outer tick4');
  })