AssetsInstallCommand.php

<?php

namespace Symfony\Bundle\FrameworkBundle\Command;

use Symfony\Component\Console\Input\InputArgument;
use Symfony\Component\Console\Input\InputOption;
use Symfony\Component\Console\Input\InputInterface;
use Symfony\Component\Console\Output\OutputInterface;
use Symfony\Component\Console\Output\Output;
use Symfony\Bundle\FrameworkBundle\Util\Filesystem;
use Symfony\Component\HttpKernel\Kernel;
use Symfony\Component\Console\Command\Command;

/*
 * This file is part of the Symfony framework.
 *
 * (c) Fabien Potencier <fabien.potencier@symfony-project.com>
 *
 * This source file is subject to the MIT license that is bundled
 * with this source code in the file LICENSE.
 */

/**
 * AssetsInstallCommand.
 *
 * @author     Fabien Potencier <fabien.potencier@symfony-project.com>
 */
class AssetsInstallCommand extends Command
{
    /**
     * @var Filesystem $filesystem
     */
    protected $filesystem;

    /**
     * @var Kernel $kernel
     */
    protected $kernel;

    /**
     * Constructor
     *
     * @param string $name
     * @param Kernel $kernel
     * @param Filesystem $filesystem
     */
    public function __construct(Kernel $kernel, Filesystem $filesystem)
    {
        parent::__construct(null);

        $this->filesystem = $filesystem;
        $this->kernel = $kernel;
    }

    /**
     * @see Command
     */
    protected function configure()
    {
        $this
            ->setDefinition(array(
                new InputArgument('target', InputArgument::REQUIRED, 'The target directory'),
            ))
            ->addOption('symlink', null, InputOption::PARAMETER_NONE, 'Symlinks the assets instead of copying it')
            ->setName('assets:install')
        ;
    }

    /**
     * @see Command
     *
     * @throws \InvalidArgumentException When the target directory does not exist
     */
    protected function execute(InputInterface $input, OutputInterface $output)
    {
        if (!is_dir($input->getArgument('target'))) {
            throw new \InvalidArgumentException(sprintf('The target directory "%s" does not exist.', $input->getArgument('target')));
        }

        foreach ($this->kernel->getBundles() as $bundle) {
            if (is_dir($originDir = $bundle->getPath().'/Resources/public')) {
                $output->writeln(sprintf('Installing assets for <comment>%s\\%s</comment>', $bundle->getNamespacePrefix(), $bundle->getName()));

                $targetDir = $input->getArgument('target').'/bundles/'.preg_replace('/bundle$/', '', strtolower($bundle->getName()));

                $this->filesystem->remove($targetDir);

                if ($input->getOption('symlink')) {
                    $this->filesystem->symlink($originDir, $targetDir);
                } else {
                    mkdir($targetDir, 0777, true);
                    $this->filesystem->mirror($originDir, $targetDir);
                }
            }
        }
    }
}

AssetsInstallCommandTest.php

<?php

namespace Symfony\Bundle\FrameworkBundle\Command;

use Symfony\Bundle\FrameworkBundle\Command\AssetsInstallCommand;
use Symfony\Component\Console\Input\ArrayInput;
use Symfony\Component\Console\Output\NullOutput;

/*
 * This file is part of the Symfony framework.
 *
 * (c) Fabien Potencier <fabien.potencier@symfony-project.com>
 *
 * This source file is subject to the MIT license that is bundled
 * with this source code in the file LICENSE.
 */

class AssetsInstallCommandTest extends \PHPUnit_Framework_TestCase
{

    /**
     * @covers Symfony\Bundle\FrameworkBundle\AssetsInstallCommand::execute()
     */
    public function testRun()
    {
        $originDir = __DIR__ . '/Resources/public';
        $targetDir = __DIR__ . '/bundles/test';

        $filesystem = $this->getMockFilesystem();
        $filesystem->expects($this->once())
            ->method('remove')
            ->with($targetDir)
        ;
        $filesystem->expects($this->once())
            ->method('mkdirs')
            ->with($targetDir, 0777)
        ;
        $filesystem->expects($this->once())
            ->method('mirror')
            ->with($originDir, $targetDir)
        ;

        $bundle = $this->getMockBundle();
        $bundle->expects($this->any())
            ->method('getName')
            ->will($this->returnValue('TestBundle'))
        ;
        $bundle->expects($this->once())
            ->method('getPath')
            ->will($this->returnValue(__DIR__))
        ;

        $kernel = $this->getMockKernel();
        $kernel->expects($this->once())
            ->method('getBundles')
            ->will($this->returnValue(array($bundle)))
        ;

        $command = new AssetsInstallCommand();
        $command->setKernel($kernel);
        $command->setFilesystem($filesystem);
        $command->run(new ArrayInput(array('target' => __DIR__)), new NullOutput());
    }

    /**
     * Gets Filesystem mock instance
     *
     * @return Symfony\Bundle\FrameworkBundle\Util\Filesystem
     */
    private function getMockFilesystem()
    {
        return $this->getMock('Symfony\Bundle\FrameworkBundle\Util\Filesystem', array(), array(), '', false, false);
    }

    /**
     * Gets Bundle mock instance
     *
     * @return Symfony\Component\HttpKernel\Bundle\Bundle
     */
    private function getMockBundle()
    {
        return $this->getMock('Symfony\Component\HttpKernel\Bundle\Bundle', array(), array(), '', false, false);
    }

    /**
     * Gets Kernel mock instance
     *
     * @return Symfony\Component\HttpKernel\Kernel
     */
    private function getMockKernel()
    {
        return $this->getMock('Symfony\Component\HttpKernel\Kernel', array(), array(), '', false, false);
    }

}

console.xml

<?xml version="1.0" ?>

<container xmlns="http://www.symfony-project.org/schema/dic/services"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="http://www.symfony-project.org/schema/dic/services http://www.symfony-project.org/schema/dic/services/services-1.0.xsd">

    <parameters>
        <parameter key="console.command.assets_install.class">Symfony\Bundle\FrameworkBundle\Command\AssetsInstallCommand</parameter>
        <parameter key="console.command.init_bundle.class">Symfony\Bundle\FrameworkBundle\Command\InitBundleCommand</parameter>
        <parameter key="console.command.router_debug.class">Symfony\Bundle\FrameworkBundle\Command\RouterDebugCommand</parameter>
        <parameter key="console.command.router_apache_dumper.class">Symfony\Bundle\FrameworkBundle\Command\RouterApacheDumperCommand</parameter>
    </parameters>

    <services>
        <service id="console.command.assets_install" class="%console.command.assets_install.class%">
            <tag name="console.command" />
            <argument type="service" id="kernel" />
            <argument type="service">
                <service class="Symfony\Bundle\FrameworkBundle\Util\Filesystem" shared="false" />
            </argument>
        </service>

        <service id="console.command.init_bundle" class="%console.command.init_bundle.class%">
            <tag name="console.command" />
        </service>

        <service id="console.command.router_debug" class="%console.command.router_debug.class%">
            <tag name="console.command" />
        </service>

        <service id="console.command.router_apache_dumper" class="%console.command.router_apache_dumper.class%">
            <tag name="console.command" />
        </service>
    </services>
</container>

That works too