Ember async test helper to wait for ember-data models to be committed

wait-for-models.js

// Registers a temporary test waiter that will be released once there are
// no longer any pending records of the given types in the store. "pending" records
// are ones where isEmpty, isLoading, isReloading, or isSaving are true.

import Ember from 'ember';

export default Ember.Test.registerAsyncHelper('waitForModels', function (app, typeNames) {
  // The context object is necessary because unregisterWaiter will unregister
  // _all_ bare function waiters if any bare function waiter is unregistered.
  // This appears to be due to a defect in Ember.compare (or maybe
  // unregisterWaiter shouldn't use Ember.compare).
  var context = Math.random();

  console.log('waitForModels', typeNames.join(' | '));
  var anyPending = true;

  var maxIterations = 250;
  var iterations = 0;

  function pendingChecker() {
    var i, records, pending = false;
    var store = app.__container__.lookup('store:main');
    iterations++;

    for (i = 0 ; iterations < maxIterations && i < typeNames.length ; i++) {
      records = store.all(typeNames[i]);
      console.log(typeNames[i], records.getEach('currentState.stateName').join(" | "));
      pending = records.isAny('isSaving') ||
        records.isAny('isEmpty') ||
        records.isAny('isLoading') ||
        records.isAny('isReloading');
      if (pending) { break; }
    }
    anyPending = pending;
  }

  var waiter = function () {
    if (anyPending) {
      Ember.run.next(null, pendingChecker);
      return false;
    } else {
      console.log('done waiting for models');
      Ember.Test.unregisterWaiter(context, waiter);
      return true;
    }
  };

  Ember.Test.registerWaiter(context, waiter);

  return wait();
});

Intended for use in integration tests for projects that use ember-data with a local database, like PouchDB via ember-pouch.

Sketch:

performOperationThatAffectsSomeModels();
waitForModels(['person', 'sandwich']);
andThen(function () {
  // verify stored data
});