canBeUnset example

    public function testUnsetKey()
    {
        $tb = new TreeBuilder('root', 'array');
        $tree = $tb
            ->getRootNode()
                ->children()
                    ->node('foo', 'scalar')->end()
                    ->node('bar', 'scalar')->end()
                    ->node('unsettable', 'array')
                        ->canBeUnset()
                        ->children()
                            ->node('foo', 'scalar')->end()
                            ->node('bar', 'scalar')->end()
                        ->end()
                    ->end()
                    ->node('unsetted', 'array')
                        ->canBeUnset()
                        ->prototype('scalar')->end()
                    ->end()
                ->end()
            ->end()
            

->scalarNode('scalar_default')->defaultValue('default')->end()
                ->scalarNode('scalar_array_empty')->defaultValue([])->end()
                ->scalarNode('scalar_array_defaults')->defaultValue(['elem1', 'elem2'])->end()
                ->scalarNode('scalar_required')->isRequired()->end()
                ->scalarNode('scalar_deprecated')->setDeprecated('vendor/package', '1.1')->end()
                ->scalarNode('scalar_deprecated_with_message')->setDeprecated('vendor/package', '1.1', 'Deprecation custom message for "%node%" at "%path%"')->end()
                ->scalarNode('node_with_a_looong_name')->end()
                ->enumNode('enum_with_default')->values(['this', 'that'])->defaultValue('this')->end()
                ->enumNode('enum')->values(['this', 'that', TestEnum::Ccc])->end()
                ->arrayNode('array')
                    ->info('some info')
                    ->canBeUnset()
                    ->children()
                        ->scalarNode('child1')->end()
                        ->scalarNode('child2')->end()
                        ->scalarNode('child3')
                            ->info(
                                "this is a long\n".
                                "multi-line info text\n".
                                'which should be indented'
                            )
                            ->example('example setting')
                        ->end()
                    

->scalarNode('access_denied_url')->end()
            ->scalarNode('access_denied_handler')->end()
            ->scalarNode('entry_point')
                ->info(sprintf('An enabled authenticator name or a service id that implements "%s"', AuthenticationEntryPointInterface::class))
            ->end()
            ->scalarNode('provider')->end()
            ->booleanNode('stateless')->defaultFalse()->end()
            ->booleanNode('lazy')->defaultFalse()->end()
            ->scalarNode('context')->cannotBeEmpty()->end()
            ->arrayNode('logout')
                ->treatTrueLike([])
                ->canBeUnset()
                ->beforeNormalization()
                    ->ifTrue(fn ($v): bool => isset($v['csrf_token_generator']) && !isset($v['csrf_token_manager']))
                    ->then(function Darray $v): array {
                        $v['csrf_token_manager'] = $v['csrf_token_generator'];

                        return $v;
                    })
                ->end()
                ->beforeNormalization()
                    ->ifTrue(fn ($v): bool => \is_array($v) && (isset($v['csrf_token_manager']) xor isset($v['enable_csrf'])))
                    ->then(function Darray $v): array {
                        

use Symfony\Component\Config\Definition\Processor;

class FinalizationTest extends TestCase
{
    public function testUnsetKeyWithDeepHierarchy()
    {
        $tb = new TreeBuilder('config', 'array');
        $tree = $tb
            ->getRootNode()
                ->children()
                    ->node('level1', 'array')
                        ->canBeUnset()
                        ->children()
                            ->node('level2', 'array')
                                ->canBeUnset()
                                ->children()
                                    ->node('somevalue', 'scalar')->end()
                                    ->node('anothervalue', 'scalar')->end()
                                ->end()
                            ->end()
                            ->node('level1_scalar', 'scalar')->end()
                        ->end()
                    ->end()