CustomNodeBuilder example

use Symfony\Component\Config\Definition\Builder\BooleanNodeDefinition;
use Symfony\Component\Config\Definition\Builder\TreeBuilder;
use Symfony\Component\Config\Tests\Fixtures\BarNode;
use Symfony\Component\Config\Tests\Fixtures\Builder\BarNodeDefinition;
use Symfony\Component\Config\Tests\Fixtures\Builder\NodeBuilder as CustomNodeBuilder;
use Symfony\Component\Config\Tests\Fixtures\Builder\VariableNodeDefinition;

class TreeBuilderTest extends TestCase
{
    public function testUsingACustomNodeBuilder()
    {
        $builder = new TreeBuilder('custom', 'array', new CustomNodeBuilder());

        $nodeBuilder = $builder->getRootNode()->children();

        $this->assertInstanceOf(CustomNodeBuilder::class, $nodeBuilder);

        $nodeBuilder = $nodeBuilder->arrayNode('deeper')->children();

        $this->assertInstanceOf(CustomNodeBuilder::class, $nodeBuilder);
    }

    public function testOverrideABuiltInNodeType()
    {