Promise chain breaking

Question

I have a promise chain (bluebird) that breaks up, and I can't figure out why.

 Promise.resolve()
   .then(function() {
     [..]
   })
   .then(function() {
     [..]
   })
   .then(function() {
     [..]
   })
   .spread(function(instance) {
     [..]
   })

This fails with TypeError: undefined is not a function on .spread. A console.log on the last .then() show it returns {}. Exchanging spread for then makes the code run. What am I doing wrong? What would make spread be undefined?

---

Update: Changing the last spread to the code below makes it work.

   .then(function(arr) {
     var instance = arr[0];
     [..]
   })

Answer 1

I'm an idiot :) missed including bluebird in that file, so it was using the native implementation of promises which doesn't have spread.