w8

Give promises (and thunks/objects/arrays) a timeout that it must finish before or else it gets rejected
Example

var w8 = require('w8');
var fastPromise = new Promise(function(res) {
  setTimeout(function() {
    res('ok1');
  }, 10);
});
var slowPromise = new Promise(function(res) {
  setTimeout(function() {
    res('ok2');
  }, 1000);
});
w8(100, fastPromise).then(function(data) {
  console.log('fastPromise was fast enough');
  console.log(data); // 'ok1'
  return w8(100, slowPromise);
}).catch(function(err) {
  console.log("slowPromisie wasn't fast enough");
});

Usage

First argument is the timeout in ms and the second is the promise/thunk/object/array, it returns a promise

Here's a sample usage with co

var w8 = require('w8');
var co = require('co');
var Promise = require('bluebird');
var fs = Promise.promisifyAll(require('fs'));

co(function *() {
  var fileReadPromise = fs.readFileAsync('package.json');
  try {
    var pkgStr = yield w8(100, fileReadPromise).toString();
    console.log('package.json contents:', pkgStr);
  } catch (e) {
    console.error('getting file took more than 100 ms');
  }
});