Describing your Symfony2 console commands with BehatBundle

command.feature

Feature: Demo greetings command
  In order to show how to describe commands in Behat
  As a Behat developer
  I need to show simple scenario based on http://symfony.com/doc/2.0/components/console.html#testing-commands

  Scenario: Running demo:greet command
    When I run "demo:greet" command
    Then I should see "/.../"

FeatureContext.php

<?php

namespace Acme\DemoBundle\Features\Context;

use Behat\BehatBundle\Context\BehatContext,
    Behat\Behat\Context\TranslatedContextInterface,
    Behat\Behat\Exception\PendingException;
use Behat\Gherkin\Node\PyStringNode,
    Behat\Gherkin\Node\TableNode;

use Symfony\Component\Console\Tester\CommandTester;
use Symfony\Bundle\FrameworkBundle\Console\Application;
use Acme\DemoBundle\Command\GreetCommand;

require_once 'PHPUnit/Autoload.php';
require_once 'PHPUnit/Framework/Assert/Functions.php';

/**
 * Feature context.
 */
class FeatureContext extends BehatContext
{
    private $application;
    private $tester;

    public function __construct($kernel)
    {
        $this->application = new Application($kernel);
        $this->application->add(new GreetCommand());
        // add other commands if needed
    }

    /**
     * @When /^I run "([^"]*)" command$/
     */
    public function iRunCommand($name)
    {
        $command = $this->application->find($name);
        $this->tester = new CommandTester($command);
        $this->tester->execute(array('command' => $command->getName()));
    }

    /**
     * @Then /^I should see "([^"]*)"$/
     */
    public function iShouldSee($regexp)
    {
        assertRegExp($regexp, $this->tester->getDisplay());
    }
}

Even if not proposed, this would work for static functions too - I guess ;-)

Some more sophisiticated approach here: https://gist.github.com/tPl0ch/6706427