WebTestCase.php

<?php

/*
 * This file is part of the Liip/FunctionalTestBundle
 *
 * (c) Lukas Kahwe Smith <smith@pooteeweet.org>
 *
 * This source file is subject to the MIT license that is bundled
 * with this source code in the file LICENSE.
 */

namespace Liip\FunctionalTestBundle\Test;

use Symfony\Bundle\FrameworkBundle\Test\WebTestCase as BaseWebTestCase;
use Symfony\Bundle\FrameworkBundle\Console\Application;
use Symfony\Bundle\FrameworkBundle\Client;
use Symfony\Component\Console\Input\ArrayInput;
use Symfony\Component\Console\Output\OutputInterface;
use Symfony\Component\Console\Output\StreamOutput;
use Symfony\Component\DomCrawler\Crawler;
use Symfony\Component\BrowserKit\Cookie;
use Symfony\Component\HttpKernel\Kernel;
use Symfony\Component\HttpFoundation\Response;
use Symfony\Component\Security\Core\Authentication\Token\TokenInterface;
use Symfony\Component\Security\Core\User\UserInterface;
use Symfony\Component\Security\Core\Authentication\Token\UsernamePasswordToken;
use Symfony\Component\DependencyInjection\ContainerInterface;
use Symfony\Component\HttpFoundation\Session\Session;
use Symfony\Component\Routing\Generator\UrlGeneratorInterface;
use Symfony\Bridge\Doctrine\ManagerRegistry;
use Symfony\Bundle\DoctrineFixturesBundle\Common\DataFixtures\Loader;
use Doctrine\Common\Persistence\ObjectManager;
use Doctrine\Common\DataFixtures\DependentFixtureInterface;
use Doctrine\Common\DataFixtures\Executor\AbstractExecutor;
use Doctrine\Common\DataFixtures\ProxyReferenceRepository;
use Doctrine\DBAL\Driver\PDOSqlite\Driver as SqliteDriver;
use Doctrine\DBAL\Platforms\MySqlPlatform;
use Doctrine\ORM\Tools\SchemaTool;
use Nelmio\Alice\Fixtures;

/**
 * @author Lea Haensenberger
 * @author Lukas Kahwe Smith <smith@pooteeweet.org>
 * @author Benjamin Eberlei <kontakt@beberlei.de>
 */
abstract class WebTestCase extends BaseWebTestCase
{
    protected $environment = 'test';
    protected $containers;
    protected $kernelDir;
    // 5 * 1024 * 1024 KB
    protected $maxMemory = 5242880;

    // RUN COMMAND
    protected $verbosityLevel;
    protected $decorated;

    /**
     * @var array
     */
    private $firewallLogins = array();

    /**
     * @var array
     */
    private static $cachedMetadatas = array();

    protected static function getKernelClass()
    {
        $dir = isset($_SERVER['KERNEL_DIR']) ? $_SERVER['KERNEL_DIR'] : self::getPhpUnitXmlDir();

        list($appname) = explode('\\', get_called_class());

        $class = $appname.'Kernel';
        $file = $dir.'/'.strtolower($appname).'/'.$class.'.php';
        if (!file_exists($file)) {
            return parent::getKernelClass();
        }
        require_once $file;

        return $class;
    }

    /**
     * Creates a mock object of a service identified by its id.
     *
     * @param string $id
     *
     * @return PHPUnit_Framework_MockObject_MockBuilder
     */
    protected function getServiceMockBuilder($id)
    {
        $service = $this->getContainer()->get($id);
        $class = get_class($service);

        return $this->getMockBuilder($class)->disableOriginalConstructor();
    }

    /**
     * Builds up the environment to run the given command.
     *
     * @param string $name
     * @param array  $params
     * @param bool   $reuseKernel
     *
     * @return string
     */
    protected function runCommand($name, array $params = array(), $reuseKernel = false)
    {
        array_unshift($params, $name);

        if (!$reuseKernel) {
            if (null !== static::$kernel) {
                static::$kernel->shutdown();
            }

            $kernel = static::$kernel = $this->createKernel(array('environment' => $this->environment));
            $kernel->boot();
        } else {
            $kernel = $this->getContainer()->get('kernel');
        }

        $application = new Application($kernel);
        $application->setAutoExit(false);

        // @codeCoverageIgnoreStart
        if ('20301' === Kernel::VERSION_ID) {
            $params = $this->configureVerbosityForSymfony20301($params);
        }
        // @codeCoverageIgnoreEnd

        $input = new ArrayInput($params);
        $input->setInteractive(false);

        $fp = fopen('php://temp/maxmemory:'.$this->maxMemory, 'r+');
        $output = new StreamOutput($fp, $this->getVerbosityLevel(), $this->getDecorated());

        $application->run($input, $output);

        rewind($fp);

        return stream_get_contents($fp);
    }

    /**
     * Retrieves the output verbosity level.
     *
     * @see Symfony\Component\Console\Output\OutputInterface for available levels
     *
     * @return int
     *
     * @throws \OutOfBoundsException If the set value isn't accepted
     */
    protected function getVerbosityLevel()
    {
        // If `null`, is not yet set
        if (null === $this->verbosityLevel) {
            // Set the global verbosity level that is set as NORMAL by the TreeBuilder in Configuration
            $level = strtoupper($this->getContainer()->getParameter('liip_functional_test.command_verbosity'));
            $verbosity = '\Symfony\Component\Console\Output\StreamOutput::VERBOSITY_'.$level;

            $this->verbosityLevel = constant($verbosity);
        }

        // If string, it is set by the developer, so check that the value is an accepted one
        if (is_string($this->verbosityLevel)) {
            $level = strtoupper($this->verbosityLevel);
            $verbosity = '\Symfony\Component\Console\Output\StreamOutput::VERBOSITY_'.$level;

            if (null === constant($verbosity)) {
                throw new \OutOfBoundsException(
                    'The set value "%s" for verbosityLevel is not valid. Accepted are: "quiet", "normal", "verbose", "very_verbose" and "debug".
                    ');
            }

            $this->verbosityLevel = constant($verbosity);
        }

        return $this->verbosityLevel;
    }

    /**
     * In Symfony 2.3.1 the verbosity level has to be set through {Symfony\Component\Console\Input\ArrayInput} and not
     * in {Symfony\Component\Console\Output\OutputInterface}.
     *
     * This method builds $params to be passed to {Symfony\Component\Console\Input\ArrayInput}.
     *
     * @codeCoverageIgnore
     *
     * @param array $params
     *
     * @return array
     */
    private function configureVerbosityForSymfony20301(array $params)
    {
        switch ($this->getVerbosityLevel()) {
            case OutputInterface::VERBOSITY_QUIET:
                $params['-q'] = '-q';
                break;

            case OutputInterface::VERBOSITY_VERBOSE:
                $params['-v'] = '';
                break;

            case OutputInterface::VERBOSITY_VERY_VERBOSE:
                $params['-vv'] = '';
                break;

            case OutputInterface::VERBOSITY_DEBUG:
                $params['-vvv'] = '';
                break;
        }

        return $params;
    }

    public function setVerbosityLevel($level)
    {
        $this->verbosityLevel = $level;
    }

    /**
     * Retrieves the flag indicating if the output should be decorated or not.
     *
     * @return bool
     */
    protected function getDecorated()
    {
        if (null === $this->decorated) {
            // Set the global decoration flag that is set to `true` by the TreeBuilder in Configuration
            $this->decorated = $this->getContainer()->getParameter('liip_functional_test.command_decoration');
        }

        // Check the local decorated flag
        if (false === is_bool($this->decorated)) {
            throw new \OutOfBoundsException(
                sprintf('`WebTestCase::decorated` has to be `bool`. "%s" given.', gettype($this->decorated))
            );
        }

        return $this->decorated;
    }

    public function isDecorated($decorated)
    {
        $this->decorated = $decorated;
    }

    /**
     * Get an instance of the dependency injection container.
     * (this creates a kernel *without* parameters).
     *
     * @return ContainerInterface
     */
    protected function getContainer()
    {
        if (!empty($this->kernelDir)) {
            $tmpKernelDir = isset($_SERVER['KERNEL_DIR']) ? $_SERVER['KERNEL_DIR'] : null;
            $_SERVER['KERNEL_DIR'] = getcwd().$this->kernelDir;
        }

        $cacheKey = $this->kernelDir.'|'.$this->environment;
        if (empty($this->containers[$cacheKey])) {
            $options = array(
                'environment' => $this->environment,
            );
            $kernel = $this->createKernel($options);
            $kernel->boot();

            $this->containers[$cacheKey] = $kernel->getContainer();
        }

        if (isset($tmpKernelDir)) {
            $_SERVER['KERNEL_DIR'] = $tmpKernelDir;
        }

        return $this->containers[$cacheKey];
    }

    /**
     * This function finds the time when the data blocks of a class definition
     * file were being written to, that is, the time when the content of the
     * file was changed.
     *
     * @param string $class The fully qualified class name of the fixture class to
     *                      check modification date on.
     *
     * @return \DateTime|null
     */
    protected function getFixtureLastModified($class)
    {
        $lastModifiedDateTime = null;

        $reflClass = new \ReflectionClass($class);
        $classFileName = $reflClass->getFileName();

        if (file_exists($classFileName)) {
            $lastModifiedDateTime = new \DateTime();
            $lastModifiedDateTime->setTimestamp(filemtime($classFileName));
        }

        return $lastModifiedDateTime;
    }

    /**
     * Determine if the Fixtures that define a database backup have been
     * modified since the backup was made.
     *
     * @param array  $classNames The fixture classnames to check
     * @param string $backup     The fixture backup SQLite database file path
     *
     * @return bool TRUE if the backup was made since the modifications to the
     *              fixtures; FALSE otherwise
     */
    protected function isBackupUpToDate(array $classNames, $backup)
    {
        $backupLastModifiedDateTime = new \DateTime();
        $backupLastModifiedDateTime->setTimestamp(filemtime($backup));

        foreach ($classNames as &$className) {
            $fixtureLastModifiedDateTime = $this->getFixtureLastModified($className);
            if ($backupLastModifiedDateTime < $fixtureLastModifiedDateTime) {
                return false;
            }
        }

        return true;
    }

    /**
     * Set the database to the provided fixtures.
     *
     * Drops the current database and then loads fixtures using the specified
     * classes. The parameter is a list of fully qualified class names of
     * classes that implement Doctrine\Common\DataFixtures\FixtureInterface
     * so that they can be loaded by the DataFixtures Loader::addFixture
     *
     * When using SQLite this method will automatically make a copy of the
     * loaded schema and fixtures which will be restored automatically in
     * case the same fixture classes are to be loaded again. Caveat: changes
     * to references and/or identities may go undetected.
     *
     * Depends on the doctrine data-fixtures library being available in the
     * class path.
     *
     * @param array  $classNames   List of fully qualified class names of fixtures to load
     * @param string $omName       The name of object manager to use
     * @param string $registryName The service id of manager registry to use
     * @param int    $purgeMode    Sets the ORM purge mode
     *
     * @return null|AbstractExecutor
     */
    protected function loadFixtures(array $classNames, $omName = null, $registryName = 'doctrine', $purgeMode = null)
    {
        $container = $this->getContainer();
        /** @var ManagerRegistry $registry */
        $registry = $container->get($registryName);
        $om = $registry->getManager($omName);
        $type = $registry->getName();

        $executorClass = 'PHPCR' === $type && class_exists('Doctrine\Bundle\PHPCRBundle\DataFixtures\PHPCRExecutor')
            ? 'Doctrine\Bundle\PHPCRBundle\DataFixtures\PHPCRExecutor'
            : 'Doctrine\\Common\\DataFixtures\\Executor\\'.$type.'Executor';
        $referenceRepository = new ProxyReferenceRepository($om);
        $cacheDriver = $om->getMetadataFactory()->getCacheDriver();

        if ($cacheDriver) {
            $cacheDriver->deleteAll();
        }

        if ('ORM' === $type) {
            $connection = $om->getConnection();
            if ($connection->getDriver() instanceof SqliteDriver) {
                $params = $connection->getParams();
                if (isset($params['master'])) {
                    $params = $params['master'];
                }

                $name = isset($params['path']) ? $params['path'] : (isset($params['dbname']) ? $params['dbname'] : false);
                if (!$name) {
                    throw new \InvalidArgumentException("Connection does not contain a 'path' or 'dbname' parameter and cannot be dropped.");
                }

                if (!isset(self::$cachedMetadatas[$omName])) {
                    self::$cachedMetadatas[$omName] = $om->getMetadataFactory()->getAllMetadata();
                    usort(self::$cachedMetadatas[$omName], function ($a, $b) { return strcmp($a->name, $b->name); });
                }
                $metadatas = self::$cachedMetadatas[$omName];

                if ($container->getParameter('liip_functional_test.cache_sqlite_db')) {
                    $backup = $container->getParameter('kernel.cache_dir').'/test_'.md5(serialize($metadatas).serialize($classNames)).'.db';
                    if (file_exists($backup) && file_exists($backup.'.ser') && $this->isBackupUpToDate($classNames, $backup)) {
                        $om->flush();
                        $om->clear();

                        $this->preFixtureRestore($om, $referenceRepository);

                        copy($backup, $name);

                        $executor = new $executorClass($om);
                        $executor->setReferenceRepository($referenceRepository);
                        $executor->getReferenceRepository()->load($backup);

                        $this->postFixtureRestore();

                        return $executor;
                    }
                }

                // TODO: handle case when using persistent connections. Fail loudly?
                $schemaTool = new SchemaTool($om);
                $schemaTool->dropDatabase($name);
                if (!empty($metadatas)) {
                    $schemaTool->createSchema($metadatas);
                }
                $this->postFixtureSetup();

                $executor = new $executorClass($om);
                $executor->setReferenceRepository($referenceRepository);
            }
        }

        if (empty($executor)) {
            $purgerClass = 'Doctrine\\Common\\DataFixtures\\Purger\\'.$type.'Purger';
            if ('PHPCR' === $type) {
                $purger = new $purgerClass($om);
                $initManager = $container->has('doctrine_phpcr.initializer_manager')
                    ? $container->get('doctrine_phpcr.initializer_manager')
                    : null;

                $executor = new $executorClass($om, $purger, $initManager);
            } else {
                $purger = new $purgerClass();
                if (null !== $purgeMode) {
                    $purger->setPurgeMode($purgeMode);
                }

                $executor = new $executorClass($om, $purger);
            }

            $executor->setReferenceRepository($referenceRepository);
            $executor->purge();
        }

        $loader = $this->getFixtureLoader($container, $classNames);

        $executor->execute($loader->getFixtures(), true);

        if (isset($name) && isset($backup)) {
            $this->preReferenceSave($om, $executor, $backup);

            $executor->getReferenceRepository()->save($backup);
            copy($name, $backup);

            $this->postReferenceSave($om, $executor, $backup);
        }

        return $executor;
    }

    /**
     * @param array  $paths        Either symfony resource locators (@ BundleName/etc) or actual file paths
     * @param bool   $append
     * @param null   $omName
     * @param string $registryName
     *
     * @return array
     *
     * @throws \BadMethodCallException
     */
    public function loadFixtureFiles(array $paths = array(), $append = false, $omName = null, $registryName = 'doctrine')
    {
        if (!class_exists('Nelmio\Alice\Fixtures')) {
            throw new \BadMethodCallException('nelmio/alice should be installed to use this method.');
        }

        /** @var ManagerRegistry $registry */
        $registry = $this->getContainer()->get($registryName);
        $om = $registry->getManager($omName);

        if ($append === false) {
            //Clean database
            $connection = $om->getConnection();
            if ($registry->getName() === 'ORM' && $connection->getDatabasePlatform() instanceof MySqlPlatform) {
                $connection->query('SET FOREIGN_KEY_CHECKS=0');
            }

            $this->loadFixtures(array());

            if ($registry->getName() === 'ORM' && $connection->getDatabasePlatform() instanceof MySqlPlatform) {
                $connection->query('SET FOREIGN_KEY_CHECKS=1');
            }
        }

        $files = array();
        $kernel = $this->getContainer()->get('kernel');
        foreach ($paths as $path) {
            if ($path[0] !== '@' && file_exists($path) === true) {
                $files[] = $path;
                continue;
            }

            $files[] = $kernel->locateResource($path);
        }

        return Fixtures::load($files, $om);
    }

    /**
     * Callback function to be executed after Schema creation.
     * Use this to execute acl:init or other things necessary.
     */
    protected function postFixtureSetup()
    {
    }

    /**
     * Callback function to be executed after Schema restore.
     *
     * @return WebTestCase
     */
    protected function postFixtureRestore()
    {
    }

    /**
     * Callback function to be executed before Schema restore.
     *
     * @param ObjectManager            $manager             The object manager
     * @param ProxyReferenceRepository $referenceRepository The reference repository
     *
     * @return WebTestCase
     */
    protected function preFixtureRestore(ObjectManager $manager, ProxyReferenceRepository $referenceRepository)
    {
    }

    /**
     * Callback function to be executed after save of references.
     *
     * @param ObjectManager    $manager        The object manager
     * @param AbstractExecutor $executor       Executor of the data fixtures
     * @param string           $backupFilePath Path of file used to backup the references of the data fixtures
     *
     * @return WebTestCase
     */
    protected function postReferenceSave(ObjectManager $manager, AbstractExecutor $executor, $backupFilePath)
    {
    }

    /**
     * Callback function to be executed before save of references.
     *
     * @param ObjectManager    $manager        The object manager
     * @param AbstractExecutor $executor       Executor of the data fixtures
     * @param string           $backupFilePath Path of file used to backup the references of the data fixtures
     *
     * @return WebTestCase
     */
    protected function preReferenceSave(ObjectManager $manager, AbstractExecutor $executor, $backupFilePath)
    {
    }

    /**
     * Retrieve Doctrine DataFixtures loader.
     *
     * @param ContainerInterface $container
     * @param array              $classNames
     *
     * @return Loader
     */
    protected function getFixtureLoader(ContainerInterface $container, array $classNames)
    {
        $loaderClass = class_exists('Symfony\Bridge\Doctrine\DataFixtures\ContainerAwareLoader')
            ? 'Symfony\Bridge\Doctrine\DataFixtures\ContainerAwareLoader'
            : (class_exists('Doctrine\Bundle\FixturesBundle\Common\DataFixtures\Loader')
                ? 'Doctrine\Bundle\FixturesBundle\Common\DataFixtures\Loader'
                : 'Symfony\Bundle\DoctrineFixturesBundle\Common\DataFixtures\Loader');

        $loader = new $loaderClass($container);

        foreach ($classNames as $className) {
            $this->loadFixtureClass($loader, $className);
        }

        return $loader;
    }

    /**
     * Load a data fixture class.
     *
     * @param Loader $loader
     * @param string $className
     */
    protected function loadFixtureClass($loader, $className)
    {
        $fixture = new $className();

        if ($loader->hasFixture($fixture)) {
            unset($fixture);

            return;
        }

        $loader->addFixture($fixture);

        if ($fixture instanceof DependentFixtureInterface) {
            foreach ($fixture->getDependencies() as $dependency) {
                $this->loadFixtureClass($loader, $dependency);
            }
        }
    }

    /**
     * Creates an instance of a lightweight Http client.
     *
     * If $authentication is set to 'true' it will use the content of
     * 'liip_functional_test.authentication' to log in.
     *
     * $params can be used to pass headers to the client, note that they have
     * to follow the naming format used in $_SERVER.
     * Example: 'HTTP_X_REQUESTED_WITH' instead of 'X-Requested-With'
     *
     * @param bool|array $authentication
     * @param array      $params
     *
     * @return Client
     */
    protected function makeClient($authentication = false, array $params = array())
    {
        if ($authentication) {
            if ($authentication === true) {
                $authentication = $this->getContainer()->getParameter('liip_functional_test.authentication');
            }

            $params = array_merge($params, array(
                'PHP_AUTH_USER' => $authentication['username'],
                'PHP_AUTH_PW' => $authentication['password'],
            ));
        }

        $client = static::createClient(array('environment' => $this->environment), $params);

        if ($this->firewallLogins) {
            // has to be set otherwise "hasPreviousSession" in Request returns false.
            $options = $client->getContainer()->getParameter('session.storage.options');

            if (!$options || !isset($options['name'])) {
                throw new \InvalidArgumentException('Missing session.storage.options#name');
            }

            $session = $client->getContainer()->get('session');
            // Since the namespace of the session changed in symfony 2.1, instanceof can be used to check the version.
            if ($session instanceof Session) {
                $session->setId(uniqid());
            }

            $client->getCookieJar()->set(new Cookie($options['name'], $session->getId()));

            /** @var $user UserInterface */
            foreach ($this->firewallLogins as $firewallName => $user) {
                $token = $this->createUserToken($user, $firewallName);

                // BC: security.token_storage is available on Symfony 2.6+
                // see http://symfony.com/blog/new-in-symfony-2-6-security-component-improvements
                if ($client->getContainer()->has('security.token_storage')) {
                    $tokenStorage = $client->getContainer()->get('security.token_storage');
                } else {
                    // This block will never be reached with Symfony 2.5+
                    // @codeCoverageIgnoreStart
                    $tokenStorage = $client->getContainer()->get('security.context');
                    // @codeCoverageIgnoreEnd
                }

                $tokenStorage->setToken($token);
                $session->set('_security_'.$firewallName, serialize($token));
            }

            $session->save();
        }

        return $client;
    }

    /**
     * Create User Token.
     *
     * Factory method for creating a User Token object for the firewall based on
     * the user object provided. By default it will be a Username/Password
     * Token based on the user's credentials, but may be overridden for custom
     * tokens in your applications.
     *
     * @param UserInterface $user         The user object to base the token off of
     * @param string        $firewallName name of the firewall provider to use
     *
     * @return TokenInterface The token to be used in the security context
     */
    protected function createUserToken(UserInterface $user, $firewallName)
    {
        return new UsernamePasswordToken(
            $user,
            null,
            $firewallName,
            $user->getRoles()
        );
    }

    /**
     * Extracts the location from the given route.
     *
     * @param string $route    The name of the route
     * @param array  $params   Set of parameters
     * @param bool   $absolute
     *
     * @return string
     */
    protected function getUrl($route, $params = array(), $absolute = UrlGeneratorInterface::ABSOLUTE_PATH)
    {
        return $this->getContainer()->get('router')->generate($route, $params, $absolute);
    }

    /**
     * Checks the success state of a response.
     *
     * @param Response $response Response object
     * @param bool     $success  to define whether the response is expected to be successful
     * @param string   $type
     */
    public function isSuccessful(Response $response, $success = true, $type = 'text/html')
    {
        try {
            $crawler = new Crawler();
            $crawler->addContent($response->getContent(), $type);
            if (!count($crawler->filter('title'))) {
                $title = '['.$response->getStatusCode().'] - '.$response->getContent();
            } else {
                $title = $crawler->filter('title')->text();
            }
        } catch (\Exception $e) {
            $title = $e->getMessage();
        }

        if ($success) {
            $this->assertTrue($response->isSuccessful(), 'The Response was not successful: '.$title);
        } else {
            $this->assertFalse($response->isSuccessful(), 'The Response was successful: '.$title);
        }
    }

    /**
     * Executes a request on the given url and returns the response contents.
     *
     * This method also asserts the request was successful.
     *
     * @param string $path           path of the requested page
     * @param string $method         The HTTP method to use, defaults to GET
     * @param bool   $authentication Whether to use authentication, defaults to false
     * @param bool   $success        to define whether the response is expected to be successful
     *
     * @return string
     */
    public function fetchContent($path, $method = 'GET', $authentication = false, $success = true)
    {
        $client = $this->makeClient($authentication);
        $client->request($method, $path);

        $content = $client->getResponse()->getContent();
        if (is_bool($success)) {
            $this->isSuccessful($client->getResponse(), $success);
        }

        return $content;
    }

    /**
     * Executes a request on the given url and returns a Crawler object.
     *
     * This method also asserts the request was successful.
     *
     * @param string $path           path of the requested page
     * @param string $method         The HTTP method to use, defaults to GET
     * @param bool   $authentication Whether to use authentication, defaults to false
     * @param bool   $success        Whether the response is expected to be successful
     *
     * @return Crawler
     */
    public function fetchCrawler($path, $method = 'GET', $authentication = false, $success = true)
    {
        $client = $this->makeClient($authentication);
        $crawler = $client->request($method, $path);

        $this->isSuccessful($client->getResponse(), $success);

        return $crawler;
    }

    /**
     * @param UserInterface $user
     *
     * @return WebTestCase
     */
    public function loginAs(UserInterface $user, $firewallName)
    {
        $this->firewallLogins[$firewallName] = $user;

        return $this;
    }

    /**
     * Asserts that the HTTP response code of the last request performed by
     * $client matches the expected code. If not, raises an error with more
     * information.
     *
     * @param $expectedStatusCode
     * @param Client $client
     */
    public function assertStatusCode($expectedStatusCode, Client $client)
    {
        $helpfulErrorMessage = null;

        if ($expectedStatusCode !== $client->getResponse()->getStatusCode()) {
            // Get a more useful error message, if available
            if ($exception = $client->getContainer()->get('liip_functional_test.exception_listener')->getLastException()) {
                $helpfulErrorMessage = $exception->getMessage();
            } elseif (count($validationErrors = $client->getContainer()->get('liip_functional_test.validator')->getLastErrors())) {
                $helpfulErrorMessage = "Unexpected validation errors:\n";

                foreach ($validationErrors as $error) {
                    $helpfulErrorMessage .= sprintf("+ %s: %s\n", $error->getPropertyPath(), $error->getMessage());
                }
            } else {
                $helpfulErrorMessage = substr($client->getResponse(), 0, 200);
            }
        }

        self::assertEquals($expectedStatusCode, $client->getResponse()->getStatusCode(), $helpfulErrorMessage);
    }

    /**
     * Assert that the last validation errors within $container match the
     * expected keys.
     *
     * @param array              $expected  A flat array of field names
     * @param ContainerInterface $container
     */
    public function assertValidationErrors(array $expected, ContainerInterface $container)
    {
        self::assertThat(
            $container->get('liip_functional_test.validator')->getLastErrors(),
            new ValidationErrorsConstraint($expected),
            'Validation errors should match.'
        );
    }
}