Application.php

<?php
// from https://gist.github.com/thunderer/4837269
// to be located in app/ folder of your Symfony application

use Symfony\Component\Console\Application as BaseApplication;
use Symfony\Component\Console\Input\InputInterface;
use Symfony\Component\Console\Input\InputOption;
use Symfony\Component\Console\Output\OutputInterface;
use Symfony\Component\HttpKernel\KernelInterface;
use Symfony\Component\HttpKernel\Kernel;
use Symfony\Component\HttpKernel\Bundle\Bundle;
use Symfony\Bundle\FrameworkBundle\Console\Shell;

class Application extends BaseApplication
{
    private $kernel;

    public function __construct(KernelInterface $kernel)
    {
        $this->kernel = $kernel;
        parent::__construct('Symfony', Kernel::VERSION.' - '.$kernel->getName().'/'.$kernel->getEnvironment().($kernel->isDebug() ? '/debug' : ''));
        $this->getDefinition()->addOption(new InputOption('--shell', '-s', InputOption::VALUE_NONE, 'Launch the shell.'));
        $this->getDefinition()->addOption(new InputOption('--process-isolation', null, InputOption::VALUE_NONE, 'Launch commands from shell as a separate processes.'));
        $this->getDefinition()->addOption(new InputOption('--env', '-e', InputOption::VALUE_REQUIRED, 'The Environment name.', $kernel->getEnvironment()));
        $this->getDefinition()->addOption(new InputOption('--no-debug', null, InputOption::VALUE_NONE, 'Switches off debug mode.'));
        $this->getDefinition()->addOption(new InputOption('--scope', null, InputOption::VALUE_REQUIRED, 'Command registering scope.'));
    }

    public function getKernel()
    {
        return $this->kernel;
    }

    public function doRun(InputInterface $input, OutputInterface $output)
    {
        $this->registerCommands($input->getParameterOption('--scope', 'project'));
        if(true === $input->hasParameterOption(array('--shell', '-s')))
        {
            $shell = new Shell($this);
            $shell->setProcessIsolation($input->hasParameterOption(array('--process-isolation')));
            $shell->run();
            return 0;
        }
        return parent::doRun($input, $output);
    }

    protected function registerCommands($scope)
    {
        $this->kernel->boot();
        if('none' === $scope)
        {
            return;
        }

        foreach($this->kernel->getBundles() as $bundle)
        {
            if('project' === $scope && false === strpos($bundle->getPath(), dirname(__DIR__).'/src/'))
            {
                continue;
            }
            if($bundle instanceof Bundle)
            {
                $bundle->registerCommands($this);
            }
        }
    }
}

console

#!/usr/bin/env php
<?php

// if you don't want to setup permissions the proper way, just uncomment the following PHP line
// read http://symfony.com/doc/current/book/installation.html#configuration-and-setup for more information
//umask(0000);

set_time_limit(0);

require_once __DIR__.'/bootstrap.php.cache';
require_once __DIR__.'/AppKernel.php';
// require your own Console Application class
require_once __DIR__.'/Application.php';

use Symfony\Component\Console\Input\ArgvInput;
use Symfony\Component\Debug\Debug;

$input = new ArgvInput();
$env = $input->getParameterOption(array('--env', '-e'), getenv('SYMFONY_ENV') ?: 'dev');
$debug = getenv('SYMFONY_DEBUG') !== '0' && !$input->hasParameterOption(array('--no-debug', '')) && $env !== 'prod';

if ($debug) {
    Debug::enable();
}

$kernel = new AppKernel($env, $debug);
$application = new Application($kernel);
$application->run($input);