adding a delay inside a Promise

promise.js

// Sometimes I have a promise chain that returns out of a promise before 
// the the execution is actually completed. Maybe i'm not returning correctly?
// Anyway, might be a common problem for a newb, like me.
// here is a way to add a delay in the promise chain to wait for the previous
// promise to complete. This is NOT best practice, but maybe it can be used as
// a troubleshooting tool.
//
...
  .then(() => {...}) 
  .then(() => {
    return new Promise(function(resolve, reject) {
      setTimeout(function() {
        resolve();
      }, 3000);
    });
  })
  .then(() => {...})
...