public function allowsUnsettingSingletons()
{
$this->factory->defineEntity('SpaceShip');
$ss = new TestEntity\SpaceShip("The mothership");
$this->factory->setSingleton('SpaceShip', $ss);
$this->factory->unsetSingleton('SpaceShip');
$this->assertNotSame($ss, $this->factory->get('SpaceShip'));
}