Add form types from service definitions.

gistfile1.php

public function process(ContainerBuilder $container)
    {   
        if (!$container->hasDefinition('form.extension')) {
            return;
        }
        
        $types = $container->getDefinition('form.extension')->getArgument(1);
        
        foreach ($container->findTaggedServiceIds('jspeck_choices.form') as $id => $attributes) {
            $def = $container->findDefinition($id);
            
            $definition = new Definition('Jspeck\Bundle\ChoicesBundle\Form\Extension\Type\ChoicesFormType');
            $definition->addMethodCall('setName', array($attributes[0]['alias']));
            $definition->addMethodCall('setClass', array($def->getClass()));
            $definition->addTag('form.type', array('alias' => $attributes[0]['alias']));
            $defName = 'jspeck_choices.form.type.' . $attributes[0]['alias'];

            $container->setDefinition($defName, $definition);
            
            $types[($attributes[0]['alias'])] = $defName;

        }
        
        $container->getDefinition('form.extension')->replaceArgument(1, $types);
    }