A test-drive of the Ember Inspector promises tab

ember-inspector-promises-tab-test.js

// # How to use this:
//
// 1. Open the Ember Inspector on an Ember app (so Ember is loaded)
// 2. Hit the 'clear' button on the Promises tab to remove any promises from the app itself
// 3. Paste this code into the console and watch how the promises inspector displays it
// 4. Twiddle, Rinse & repeat
// 5. More info at 
//   * https://github.com/kriskowal/q/blob/v1/design/README.js (great for understanding promises)
//   * http://emberjs.com/api/classes/Ember.RSVP.Promise.html (Ember promise implementation specifics)

// ==========================

// Ember.RSVP.Promise(resolverFunction, label)
var p1 = new Ember.RSVP.Promise(function(resolve, reject) {
  
  var val = "I am some vital data";

  // simulate a slow server  
  setTimeout(function () {
      resolve(val);
  }, 5000);

  // THIS WILL NEVER FAIL!
  // but if it did ...
  // var reason = new Error('The thing that should not be');
  //reject(reason);
  
}, "Pulling vital data from the Internets");

// .then(resolveCallback, rejectCallback, label)
var p2 = p1.then(
  function (p1val) {
    return p1val + " (has been validated)";
  },
  function (p1err) {
    // handle error from the operation that created p1
  },
  "Running spooky validations on it from a distance"
);

var p3 = p2.then(function (p2val) {
  return p2val + " (has been converted)";
}, null, "Converting it for use in our app")