QUnit.test('old dependent keys should not trigger property changes', function() {
  let obj1 = Object.create(null);
  defineProperty(obj1, 'foo', null);
  defineProperty(obj1, 'bar', alias('foo'));
  defineProperty(obj1, 'baz', alias('foo'));
  defineProperty(obj1, 'baz', alias('bar')); // redefine baz

  let ref = observe(obj1, 'baz');
  equal(ref.value(), null, "The value starts out null");

  set(obj1, 'foo', 'FOO');
  equal(ref.value(), 'FOO', "And it sees the new value");

  set(obj1, 'foo', 'OOF');
});

QUnit.test('can iterate over a list of computed properties for a class', function() {
  let MyClass = EmberObject.extend({
    foo: computed(function() {}),

    fooDidChange: observer('foo', function() {}),

    bar: computed(function() {}),

    qux: alias('foo')
  });

  let SubClass = MyClass.extend({
    baz: computed(function() {})
  });

  SubClass.reopen({
    bat: computed(function() {}).meta({ iAmBat: true })
  });

  let list = [];

  MyClass.eachComputedProperty(function(name) {
    list.push(name);
  });

  deepEqual(list.sort(), ['bar', 'foo', 'qux'], 'watched and unwatched computed properties are iterated');

  list = [];

  SubClass.eachComputedProperty(function(name, meta) {
    list.push(name);

    if (name === 'bat') {
      deepEqual(meta, { iAmBat: true });
    } else {
      deepEqual(meta, {});
    }
  });

  deepEqual(list.sort(), ['bar', 'bat', 'baz', 'foo', 'qux'], 'all inherited properties are included');
});

 assert.throws(function() {
   defineProperty(obj, 'bar', alias('bar'));
 }, /Setting alias \'bar\' on self/);