It looks like you're just missing a return
new Promise(function(resolve, reject) {
console.log(1)
resolve()
})
.then(() => console.log(2))
.then(() => { // how to reject this one if internal fails?
return new Promise(function(resolve, reject) {
reject(new Error('Polling failure'));
})
.then(() => console.log(21))
})
.then(() => console.log(3))
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