chai as promised not working without `notify`

package.json

{
	"name": "application-name",
	"version": "0.0.1",
	"dependencies": {
		"q": "*"
	},
	"devDependencies": {
		"mocha": "1.19.0",
		"chai": "*",
		"chai-as-promised": "*"
	}
}

test_test.js

var chai = require('chai');
var assert = chai.assert;
chai.use(require('chai-as-promised'));
var Q = require('q');

test('this test should fail and ineed does so because it uses `notify`', function(done) {
	var promise = getPromise();

	assert.becomes(promise, 6).notify(done);
});

test('this test should fail but does not because it does not use `notify`', function() {
	var promise = getPromise();

	assert.becomes(promise, 6);
});

function getPromise() {
	var deferred = Q.defer();
	setTimeout(function() {
		deferred.resolve(5);
	}, 1000);
	return deferred.promise;
}