Contao\CoreBundle\ContaoManager\Plugin::getRouteCollection PHP Method

    public function getRouteCollection(LoaderResolverInterface $resolver, KernelInterface $kernel)
    {
        return $resolver->resolve(__DIR__ . '/../Resources/config/routing.yml')->load(__DIR__ . '/../Resources/config/routing.yml');
    }

 /**
  * Tests the getRouteCollection() method.
  */
 public function testGetRouteCollection()
 {
     $loader = $this->getMockBuilder('Symfony\\Component\\Config\\Loader\\LoaderInterface')->setMethods(['load', 'supports', 'getResolver', 'setResolver'])->getMock();
     $loader->expects($this->once())->method('load');
     $resolver = $this->getMockBuilder('Symfony\\Component\\Config\\Loader\\LoaderResolverInterface')->setMethods(['resolve'])->getMock();
     $resolver->expects($this->any())->method('resolve')->willReturn($loader);
     $plugin = new Plugin();
     $plugin->getRouteCollection($resolver, $this->getMock('Symfony\\Component\\HttpKernel\\KernelInterface'));
 }