Make Behat/Mink create a screenshot when a test fails

gistfile1.php

<?php

class FeatureContext extends MinkContext {
	
	/**
	 * Take screenshot when step fails.
	 * Works only with Selenium2Driver.
	 *
	 * @AfterStep
	 */
	public function takeScreenshotAfterFailedStep(Behat\Behat\Event\StepEvent $event) {
	    if (Behat\Behat\Event\StepEvent::FAILED === $event->getResult()) {
			$driver = $this->getSession()->getDriver();
			if ($driver instanceof Behat\Mink\Driver\Selenium2Driver) {
				$step = $event->getStep();
				$id = $step->getParent()->getTitle() . '.' . $step->getType() . ' ' . $step->getText();
				$fileName = 'Fail.'.preg_replace('/[^a-zA-Z0-9-_\.]/','_', $id) . '.jpg';
				file_put_contents($fileName, $driver->getScreenshot());
			}
		}
	}
	
}