Symfony\Component\DependencyInjection\ContainerBuilder::getServiceIds PHP Method

    public function getServiceIds()
    {
        return array_unique(array_merge(array_keys($this->getDefinitions()), array_keys($this->aliasDefinitions), parent::getServiceIds()));
    }

 public function testConfig()
 {
     $this->createFullConfiguration();
     $this->assertParameter('foo_key', 'freshdesk_api_key');
     $this->assertParameter('bar_domain', 'freshdesk_domain');
     $this->assertContains('freshdesk', $this->containerBuilder->getServiceIds());
 }