Twig extension test case

TwigExtensionTestCase.php

<?php
namespace ChubProduction\Bundle\XXXBundle\Tests;

/**
 * TwigExtensionTestCase
 *
 * @author Vladimir Chub <v@chub.com.ua>
 */
trait TwigExtensionTestCase
{
    /**
	 * @var \Twig_Environment $twig
	 */
	private $twig;

	/**
	 * @return \Twig_ExtensionInterface[] Extensions to register
	 */
	abstract protected function getExtensions();

	public function setUpTwigExtension()
	{
		$this->twig = new \Twig_Environment(new \Twig_Loader_String());
		$this->twig->setExtensions($this->getExtensions());
	}

	/**
	 * @param string $string
	 * @param mixed  $context
	 *
	 * @return string
	 */
	public function render($string, $context)
	{
		return $this->twig->render($string, $context);
	}

	/**
	 * @return \Twig_Environment
	 */
	public function getTwig()
	{
		return $this->twig;
	}

	/**
	 * @param string $expected
	 * @param string $string
	 * @param array  $context
	 * @param string $message
	 */
	protected function assertTwigEquals($expected, $string, $context, $message = '')
	{
		$actual = $this->render($string, $context);
		$this->assertEquals($expected, $actual, $message);
	}

	/**
	 * @param string $expected
	 * @param string $string
	 * @param array  $context
	 * @param string $message
	 */
	protected function assertTwigContains($expected, $string, $context, $message = '')
	{
		$actual = $this->render($string, $context);
		$this->assertContains($expected, $actual, $message);
	}
}