/**
  * @covers ::getActiveBalancers
  */
 public function testgetActiveBalancers()
 {
     $serverList = new BalancerServerList();
     $serverList->append(Server::create(['name' => 'bal-123', 'services' => ['varnish' => ['status' => 'active']]]));
     $serverList->append(Server::create(['name' => 'bal-234', 'services' => ['varnish' => ['status' => 'hot_spare']]]));
     $serverList->append(Server::create(['name' => 'bal-345', 'services' => []]));
     $this->assertEquals(3, count($serverList));
     /** @var BalancerServerListInterface $activeBals */
     $activeBals = $serverList->getActiveBalancers();
     $this->assertEquals(1, count($activeBals));
     /** @var ServerInterface $activeBal */
     $activeBal = $activeBals[0];
     $this->assertEquals('bal-123', $activeBal->getName());
 }
 /**
  * {@inheritdoc}
  */
 public function getBalancerServers()
 {
     $balancerServers = new BalancerServerList();
     /** @var ServerInterface $server */
     foreach ($this as $server) {
         if ($server->isBalancerServer()) {
             $balancerServers->append($server);
         }
     }
     return $balancerServers;
 }