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.. index::
   single: Tests

Testing

Whenever you write a new line of code, you also potentially add new bugs. To build better and more reliable applications, you should test your code using both functional and unit tests.

The PHPUnit Testing Framework

Symfony integrates with an independent library called PHPUnit to give you a rich testing framework. This article won't cover PHPUnit itself, which has its own excellent documentation.

Before creating your first test, install the PHPUnit Bridge component, which wraps the original PHPUnit binary to provide additional features:

$ composer require --dev symfony/phpunit-bridge

After the library downloads, try executing PHPUnit by running (the first time you run this, it will download PHPUnit itself and make its classes available in your app):

$ ./bin/phpunit

Note

The ./bin/phpunit command is created by :ref:`Symfony Flex <symfony-flex>` when installing the phpunit-bridge package. If the command is missing, you can remove the package (composer remove symfony/phpunit-bridge) and install it again. Another solution is to remove the project's symfony.lock file and run composer install to force the execution of all Symfony Flex recipes.

Each test - whether it's a unit test or a functional test - is a PHP class that should live in the tests/ directory of your application. If you follow this rule, then you can run all of your application's tests with the same command as before.

PHPUnit is configured by the phpunit.xml.dist file in the root of your Symfony application.

Tip

Code coverage can be generated with the --coverage-* options, see the help information that is shown when using --help for more information.

.. index::
   single: Tests; Unit tests

Unit Tests

A unit test is a test against a single PHP class, also called a unit. If you want to test the overall behavior of your application, see the section about :ref:`Functional Tests <functional-tests>`.

Writing Symfony unit tests is no different from writing standard PHPUnit unit tests. Suppose, for example, that you have an incredibly simple class called Calculator in the src/Util/ directory of the app:

// src/Util/Calculator.php
namespace App\Util;

class Calculator
{
    public function add($a, $b)
    {
        return $a + $b;
    }
}

To test this, create a CalculatorTest file in the tests/Util directory of your application:

// tests/Util/CalculatorTest.php
namespace App\Tests\Util;

use App\Util\Calculator;
use PHPUnit\Framework\TestCase;

class CalculatorTest extends TestCase
{
    public function testAdd()
    {
        $calculator = new Calculator();
        $result = $calculator->add(30, 12);

        // assert that your calculator added the numbers correctly!
        $this->assertEquals(42, $result);
    }
}

Note

By convention, the tests/ directory should replicate the directory of your application for unit tests. So, if you're testing a class in the src/Util/ directory, put the test in the tests/Util/ directory.

Just like in your real application - autoloading is automatically enabled via the vendor/autoload.php file (as configured by default in the phpunit.xml.dist file).

You can also limit a test run to a directory or a specific test file:

# run all tests of the application
$ php bin/phpunit

# run all tests in the Util/ directory
$ php bin/phpunit tests/Util

# run tests for the Calculator class
$ php bin/phpunit tests/Util/CalculatorTest.php
.. index::
   single: Tests; Functional tests

Functional Tests

Functional tests check the integration of the different layers of an application (from the routing to the views). They are no different from unit tests as far as PHPUnit is concerned, but they have a very specific workflow:

  • Make a request;
  • Click on a link or submit a form;
  • Test the response;
  • Rinse and repeat.

Before creating your first test, install these packages that provide some of the utilities used in the functional tests:

$ composer require --dev symfony/browser-kit symfony/css-selector

Your First Functional Test

Functional tests are PHP files that typically live in the tests/Controller directory of your application. If you want to test the pages handled by your PostController class, start by creating a new PostControllerTest.php file that extends a special WebTestCase class.

As an example, a test could look like this:

// tests/Controller/PostControllerTest.php
namespace App\Tests\Controller;

use Symfony\Bundle\FrameworkBundle\Test\WebTestCase;

class PostControllerTest extends WebTestCase
{
    public function testShowPost()
    {
        $client = static::createClient();

        $client->request('GET', '/post/hello-world');

        $this->assertEquals(200, $client->getResponse()->getStatusCode());
    }
}

Tip

To run your functional tests, the WebTestCase class needs to know which is the application kernel to bootstrap it. The kernel class is usually defined in the KERNEL_CLASS environment variable (included in the default .env.test file provided by Symfony):

If your use case is more complex, you can also override the createKernel() or getKernelClass() methods of your functional test, which take precedence over the KERNEL_CLASS env var.

In the above example, you validated that the HTTP response was successful. The next step is to validate that the page actually contains the expected content. The createClient() method returns a client, which is like a browser that you'll use to crawl your site:

$crawler = $client->request('GET', '/post/hello-world');

The request() method (read :ref:`more about the request method <testing-request-method-sidebar>`) returns a :class:`Symfony\\Component\\DomCrawler\\Crawler` object which can be used to select elements in the response, click on links and submit forms.

Tip

The Crawler only works when the response is an XML or an HTML document. To get the raw content response, call $client->getResponse()->getContent().

The crawler integrates with the symfony/css-selector component to give you the power of CSS selectors to find content in a page. To install the CSS selector component, run:

$ composer require --dev symfony/css-selector

Now you can use CSS selectors with the crawler. To assert that the phrase "Hello World" is present in the page's main title, you can use this assertion:

$this->assertSelectorTextContains('html h1.title', 'Hello World');

This assertion checks if the first element matching the CSS selector contains the given text. This assert calls $crawler->filter('html h1.title') internally, which allows you to use CSS selectors to filter any HTML element in the page and check for its existence, attributes, text, etc.

The assertSelectorTextContains method is not a native PHPUnit assertion and is available thanks to the WebTestCase class.

The crawler can also be used to interact with the page. Click on a link by first selecting it with the crawler using either an XPath expression or a CSS selector, then use the client to click on it:

$link = $crawler
    ->filter('a:contains("Greet")') // find all links with the text "Greet"
    ->eq(1) // select the second link in the list
    ->link()
;

// and click it
$crawler = $client->click($link);

Submitting a form is very similar: select a form button, optionally override some form values and submit the corresponding form:

$form = $crawler->selectButton('submit')->form();

// set some values
$form['name'] = 'Lucas';
$form['form_name[subject]'] = 'Hey there!';

// submit the form
$crawler = $client->submit($form);

Tip

The form can also handle uploads and contains methods to fill in different types of form fields (e.g. select() and tick()). For details, see the Forms section below.

Now that you can navigate through an application, use assertions to test that it actually does what you expect it to. Use the Crawler to make assertions on the DOM:

// asserts that the response matches a given CSS selector.
$this->assertGreaterThan(0, $crawler->filter('h1')->count());

Or test against the response content directly if you just want to assert that the content contains some text or in case that the response is not an XML/HTML document:

$this->assertStringContainsString(
    'Hello World',
    $client->getResponse()->getContent()
);

Tip

Instead of installing each testing dependency individually, you can use the test :ref:`Symfony pack <symfony-packs>` to install all those dependencies at once:

$ composer require --dev symfony/test-pack
.. index::
   single: Tests; Assertions

Useful Assertions

To get you started faster, here is a list of the most common and useful test assertions:

use Symfony\Component\HttpFoundation\Response;

// ...

// asserts that there is at least one h2 tag with the class "subtitle"
// the third argument is an optional message shown on failed tests
$this->assertGreaterThan(0, $crawler->filter('h2.subtitle')->count(),
    'There is at least one subtitle'
);

// asserts that there are exactly 4 h2 tags on the page
$this->assertCount(4, $crawler->filter('h2'));

// asserts that the "Content-Type" header is "application/json"
$this->assertResponseHeaderSame('Content-Type', 'application/json');
// equivalent to:
$this->assertTrue($client->getResponse()->headers->contains(
    'Content-Type', 'application/json'
));

// asserts that the response content contains a string
$this->assertStringContainsString('foo', $client->getResponse()->getContent());
// ...or matches a regex
$this->assertRegExp('/foo(bar)?/', $client->getResponse()->getContent());

// asserts that the response status code is 2xx
$this->assertResponseIsSuccessful();
// equivalent to:
$this->assertTrue($client->getResponse()->isSuccessful());

// asserts that the response status code is 404 Not Found
$this->assertTrue($client->getResponse()->isNotFound());

// asserts a specific status code
$this->assertResponseStatusCodeSame(201);
// HTTP status numbers are available as constants too:
// e.g. 201 === Symfony\Component\HttpFoundation\Response::HTTP_CREATED
// equivalent to:
$this->assertEquals(201, $client->getResponse()->getStatusCode());

// asserts that the response is a redirect to /demo/contact
$this->assertResponseRedirects('/demo/contact');
// equivalent to:
$this->assertTrue($client->getResponse()->isRedirect('/demo/contact'));
// ...or check that the response is a redirect to any URL
$this->assertResponseRedirects();

Testing against Different Sets of Data

It's common to have to execute the same test against different sets of data to check the multiple conditions code must handle. This is solved with PHPUnit's data providers, which work both for unit and functional tests.

First, add one or more arguments to your test method and use them inside the test code. Then, define another method which returns a nested array with the arguments to use on each test run. Lastly, add the @dataProvider annotation to associate both methods:

/**
 * @dataProvider provideUrls
 */
public function testPageIsSuccessful($url)
{
    $client = self::createClient();
    $client->request('GET', $url);

    $this->assertTrue($client->getResponse()->isSuccessful());
}

public function provideUrls()
{
    return [
        ['/'],
        ['/blog'],
        ['/contact'],
        // ...
    ];
}
.. index::
   single: Tests; Client

Working with the Test Client

The test client simulates an HTTP client like a browser and makes requests into your Symfony application:

$crawler = $client->request('GET', '/post/hello-world');

The request() method takes the HTTP method and a URL as arguments and returns a Crawler instance.

Tip

Hardcoding the request URLs is a best practice for functional tests. If the test generates URLs using the Symfony router, it won't detect any change made to the application URLs which may impact the end users.

More about the request() Method:

The full signature of the request() method is:

request(
    string $method,
    string $uri,
    array $parameters = [],
    array $files = [],
    array $server = [],
    string $content = null,
    bool $changeHistory = true
)

The server array is the raw values that you'd expect to normally find in the PHP $_SERVER superglobal. For example, to set the Content-Type and Referer HTTP headers, you'd pass the following (mind the HTTP_ prefix for non standard headers):

$client->request(
    'GET',
    '/post/hello-world',
    [],
    [],
    [
        'CONTENT_TYPE' => 'application/json',
        'HTTP_REFERER' => '/foo/bar',
    ]
);

Use the crawler to find DOM elements in the response. These elements can then be used to click on links and submit forms:

$crawler = $client->clickLink('Go elsewhere...');

$crawler = $client->submitForm('validate', ['name' => 'Fabien']);

The clickLink() and submitForm() methods both return a Crawler object. These methods are the best way to browse your application as it takes care of a lot of things for you, like detecting the HTTP method from a form and giving you a nice API for uploading files.

The request() method can also be used to simulate form submissions directly or perform more complex requests. Some useful examples:

// submits a form directly (but using the Crawler is easier!)
$client->request('POST', '/submit', ['name' => 'Fabien']);

// submits a raw JSON string in the request body
$client->request(
    'POST',
    '/submit',
    [],
    [],
    ['CONTENT_TYPE' => 'application/json'],
    '{"name":"Fabien"}'
);

// Form submission with a file upload
use Symfony\Component\HttpFoundation\File\UploadedFile;

$photo = new UploadedFile(
    '/path/to/photo.jpg',
    'photo.jpg',
    'image/jpeg',
    null
);
$client->request(
    'POST',
    '/submit',
    ['name' => 'Fabien'],
    ['photo' => $photo]
);

// Perform a DELETE request and pass HTTP headers
$client->request(
    'DELETE',
    '/post/12',
    [],
    [],
    ['PHP_AUTH_USER' => 'username', 'PHP_AUTH_PW' => 'pa$$word']
);

Last but not least, you can force each request to be executed in its own PHP process to avoid any side effects when working with several clients in the same script:

$client->insulate();

AJAX Requests

The Client provides a :method:`Symfony\\Component\\BrowserKit\\AbstractBrowser::xmlHttpRequest` method, which has the same arguments as the request() method, and it's a shortcut to make AJAX requests:

// the required HTTP_X_REQUESTED_WITH header is added automatically
$client->xmlHttpRequest('POST', '/submit', ['name' => 'Fabien']);

Browsing

The Client supports many operations that can be done in a real browser:

$client->back();
$client->forward();
$client->reload();

// clears all cookies and the history
$client->restart();

Note

The back() and forward() methods skip the redirects that may have occurred when requesting a URL, as normal browsers do.

Accessing Internal Objects

If you use the client to test your application, you might want to access the client's internal objects:

$history = $client->getHistory();
$cookieJar = $client->getCookieJar();

You can also get the objects related to the latest request:

// the HttpKernel request instance
$request = $client->getRequest();

// the BrowserKit request instance
$request = $client->getInternalRequest();

// the HttpKernel response instance
$response = $client->getResponse();

// the BrowserKit response instance
$response = $client->getInternalResponse();

// the Crawler instance
$crawler = $client->getCrawler();

Accessing the Container

It's highly recommended that a functional test only tests the response. But under certain very rare circumstances, you might want to access some services to write assertions. Given that services are private by default, test classes define a property that stores a special container created by Symfony which allows fetching both public and all non-removed private services:

// gives access to the same services used in your test, unless you're using
// $client->insulate() or using real HTTP requests to test your application
// don't forget to call self::bootKernel() before, otherwise, the container
// will be empty
$container = self::$container;

For a list of services available in your application, use the debug:container command.

If a private service is never used in your application (outside of your test), it is removed from the container and cannot be accessed as described above. In that case, you can create a public alias in the test environment and access it via that alias:

.. configuration-block::

    .. code-block:: yaml

        # config/services_test.yaml
        services:
            # access the service in your test via
            # self::$container->get('test.App\Test\SomeTestHelper')
            test.App\Test\SomeTestHelper:
                # the id of the private service
                alias: 'App\Test\SomeTestHelper'
                public: true

    .. code-block:: xml

        <!-- config/services_test.xml -->
        <?xml version="1.0" encoding="UTF-8" ?>
        <container xmlns="http://symfony.com/schema/dic/services"
            xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
            xsi:schemaLocation="http://symfony.com/schema/dic/services
                https://symfony.com/schema/dic/services/services-1.0.xsd">

            <services>
                <!-- ... -->

                <service id="test.App\Test\SomeTestHelper" alias="App\Test\SomeTestHelper" public="true"/>
            </services>
        </container>

    .. code-block:: php

        // config/services_test.php
        namespace Symfony\Component\DependencyInjection\Loader\Configurator;

        use App\Service\MessageGenerator;
        use App\Updates\SiteUpdateManager;

        return function(ContainerConfigurator $configurator) {
            // ...

            $services->alias('test.App\Test\SomeTestHelper', 'App\Test\SomeTestHelper')->public();
        };

Tip

The special container that gives access to private services exists only in the test environment and is itself a service that you can get from the real container using the test.service_container id.

Tip

If the information you need to check is available from the profiler, use it instead.

Logging in Users (Authentication)

.. versionadded:: 5.1

    The ``loginUser()`` method was introduced in Symfony 5.1.

When you want to add functional tests for protected pages, you have to first "login" as a user. Reproducing the actual steps - such as submitting a login form - make a test very slow. For this reason, Symfony provides a loginUser() method to simulate logging in in your functional tests.

Instead of login in with real users, it's recommended to create a user only for tests. You can do that with Doctrine :ref:`data fixtures <user-data-fixture>`, to load the testing users only in the test database.

After loading users in your database, use your user repository to fetch this user and use :method:`$client->loginUser() <Symfony\\Bundle\\FrameworkBundle\\KernelBrowser::loginUser>` to simulate a login request:

// tests/Controller/ProfileControllerTest.php
namespace App\Tests\Controller;

use App\Repository\UserRepository;
use Symfony\Bundle\FrameworkBundle\Test\WebTestCase;

class ProfileControllerTest extends WebTestCase
{
    // ...

    public function testVisitingWhileLoggedIn()
    {
        $client = static::createClient();
        $userRepository = static::$container->get(UserRepository::class);

        // retrieve the test user
        $testUser = $userRepository->findOneByEmail('john.doe@example.com');

        // simulate $testUser being logged in
        $client->loginUser($testUser);

        // test e.g. the profile page
        $client->request('GET', '/profile');
        $this->assertResponseIsSuccessful();
        $this->assertSelectorTextContains('h1', 'Hello John!');
    }
}

You can pass any :class:`Symfony\\Component\\Security\\Core\\User\\UserInterface` instance to loginUser(). This method creates a special :class:`Symfony\\Bundle\\FrameworkBundle\\Test\\TestBrowserToken` object and stores in the session of the test client.

Accessing the Profiler Data

On each request, you can enable the Symfony profiler to collect data about the internal handling of that request. For example, the profiler could be used to verify that a given page executes less than a certain number of database queries when loading.

To get the Profiler for the last request, do the following:

// enables the profiler for the very next request
$client->enableProfiler();

$crawler = $client->request('GET', '/profiler');

// gets the profile
$profile = $client->getProfile();

For specific details on using the profiler inside a test, see the :doc:`/testing/profiling` article.

Redirecting

When a request returns a redirect response, the client does not follow it automatically. You can examine the response and force a redirection afterwards with the followRedirect() method:

$crawler = $client->followRedirect();

If you want the client to automatically follow all redirects, you can force them by calling the followRedirects() method before performing the request:

$client->followRedirects();

If you pass false to the followRedirects() method, the redirects will no longer be followed:

$client->followRedirects(false);

Reporting Exceptions

Debugging exceptions in functional tests may be difficult because by default they are caught and you need to look at the logs to see which exception was thrown. Disabling catching of exceptions in the test client allows the exception to be reported by PHPUnit:

$client->catchExceptions(false);
.. index::
   single: Tests; Crawler

The Crawler

A Crawler instance is returned each time you make a request with the Client. It allows you to traverse HTML documents, select nodes, find links and forms.

Traversing

Like jQuery, the Crawler has methods to traverse the DOM of an HTML/XML document. For example, the following finds all input[type=submit] elements, selects the last one on the page, and then selects its immediate parent element:

$newCrawler = $crawler->filter('input[type=submit]')
    ->last()
    ->parents()
    ->first()
;

Many other methods are also available:

filter('h1.title')
Nodes that match the CSS selector.
filterXpath('h1')
Nodes that match the XPath expression.
eq(1)
Node for the specified index.
first()
First node.
last()
Last node.
siblings()
Siblings.
nextAll()
All following siblings.
previousAll()
All preceding siblings.
parents()
Returns the parent nodes.
children()
Returns children nodes.
reduce($lambda)
Nodes for which the callable does not return false.

Since each of these methods returns a new Crawler instance, you can narrow down your node selection by chaining the method calls:

$crawler
    ->filter('h1')
    ->reduce(function ($node, $i) {
        if (!$node->attr('class')) {
            return false;
        }
    })
    ->first()
;

Tip

Use the count() function to get the number of nodes stored in a Crawler: count($crawler)

Extracting Information

The Crawler can extract information from the nodes:

use Symfony\Component\DomCrawler\Crawler;

// returns the attribute value for the first node
$crawler->attr('class');

// returns the node value for the first node
$crawler->text();

// returns the default text if the node does not exist
$crawler->text('Default text content');

// pass TRUE as the second argument of text() to remove all extra white spaces, including
// the internal ones (e.g. "  foo\n  bar    baz \n " is returned as "foo bar baz")
$crawler->text(null, true);

// extracts an array of attributes for all nodes
// (_text returns the node value)
// returns an array for each element in crawler,
// each with the value and href
$info = $crawler->extract(['_text', 'href']);

// executes a lambda for each node and return an array of results
$data = $crawler->each(function (Crawler $node, $i) {
    return $node->attr('href');
});

Links

Use the clickLink() method to click on the first link that contains the given text (or the first clickable image with that alt attribute):

$client = static::createClient();
$client->request('GET', '/post/hello-world');

$client->clickLink('Click here');

If you need access to the :class:`Symfony\\Component\\DomCrawler\\Link` object that provides helpful methods specific to links (such as getMethod() and getUri()), use the selectLink() method instead:

$client = static::createClient();
$crawler = $client->request('GET', '/post/hello-world');

$link = $crawler->selectLink('Click here')->link();
$client->click($link);

Forms

Use the submitForm() method to submit the form that contains the given button:

$client = static::createClient();
$client->request('GET', '/post/hello-world');

$crawler = $client->submitForm('Add comment', [
    'comment_form[content]' => '...',
]);

The first argument of submitForm() is the text content, id, value or name of any <button> or <input type="submit"> included in the form. The second optional argument is used to override the default form field values.

Note

Notice that you select form buttons and not forms as a form can have several buttons; if you use the traversing API, keep in mind that you must look for a button.

If you need access to the :class:`Symfony\\Component\\DomCrawler\\Form` object that provides helpful methods specific to forms (such as getUri(), getValues() and getFields()) use the selectButton() method instead:

$client = static::createClient();
$crawler = $client->request('GET', '/post/hello-world');

$buttonCrawlerNode = $crawler->selectButton('submit');

// select the form that contains this button
$form = $buttonCrawlerNode->form();

// you can also pass an array of field values that overrides the default ones
$form = $buttonCrawlerNode->form([
    'my_form[name]'    => 'Fabien',
    'my_form[subject]' => 'Symfony rocks!',
]);

// you can pass a second argument to override the form HTTP method
$form = $buttonCrawlerNode->form([], 'DELETE');

// submit the Form object
$client->submit($form);

The field values can also be passed as a second argument of the submit() method:

$client->submit($form, [
    'my_form[name]'    => 'Fabien',
    'my_form[subject]' => 'Symfony rocks!',
]);

For more complex situations, use the Form instance as an array to set the value of each field individually:

// changes the value of a field
$form['my_form[name]'] = 'Fabien';
$form['my_form[subject]'] = 'Symfony rocks!';

There is also a nice API to manipulate the values of the fields according to their type:

// selects an option or a radio
$form['country']->select('France');

// ticks a checkbox
$form['like_symfony']->tick();

// uploads a file
$form['photo']->upload('/path/to/lucas.jpg');

// In the case of a multiple file upload
$form['my_form[field][O]']->upload('/path/to/lucas.jpg');
$form['my_form[field][1]']->upload('/path/to/lisa.jpg');

Tip

Instead of hardcoding the form name as part of the field names (e.g. my_form[...] in previous examples), you can use the :method:`Symfony\\Component\\DomCrawler\\Form::getName` method to get the form name.

Tip

If you purposefully want to select "invalid" select/radio values, see :ref:`components-dom-crawler-invalid`.

Tip

You can get the values that will be submitted by calling the getValues() method on the Form object. The uploaded files are available in a separate array returned by getFiles(). The getPhpValues() and getPhpFiles() methods also return the submitted values, but in the PHP format (it converts the keys with square brackets notation - e.g. my_form[subject] - to PHP arrays).

Tip

The submit() and submitForm() methods define optional arguments to add custom server parameters and HTTP headers when submitting the form:

$client->submit($form, [], ['HTTP_ACCEPT_LANGUAGE' => 'es']);
$client->submitForm($button, [], 'POST', ['HTTP_ACCEPT_LANGUAGE' => 'es']);
Adding and Removing Forms to a Collection

If you use a :doc:`Collection of Forms </form/form_collections>`, you can't add fields to an existing form with $form['task[tags][0][name]'] = 'foo';. This results in an error Unreachable field "…" because $form can only be used in order to set values of existing fields. In order to add new fields, you have to add the values to the raw data array:

// gets the form
$form = $crawler->filter('button')->form();

// gets the raw values
$values = $form->getPhpValues();

// adds fields to the raw values
$values['task']['tags'][0]['name'] = 'foo';
$values['task']['tags'][1]['name'] = 'bar';

// submits the form with the existing and new values
$crawler = $client->request($form->getMethod(), $form->getUri(), $values,
    $form->getPhpFiles());

// the 2 tags have been added to the collection
$this->assertEquals(2, $crawler->filter('ul.tags > li')->count());

Where task[tags][0][name] is the name of a field created with JavaScript.

You can remove an existing field, e.g. a tag:

// gets the values of the form
$values = $form->getPhpValues();

// removes the first tag
unset($values['task']['tags'][0]);

// submits the data
$crawler = $client->request($form->getMethod(), $form->getUri(),
    $values, $form->getPhpFiles());

// the tag has been removed
$this->assertEquals(0, $crawler->filter('ul.tags > li')->count());
.. index::
   pair: Tests; Configuration

Testing Configuration

The Client used by functional tests creates a Kernel that runs in a special test environment. Since Symfony loads the config/packages/test/*.yaml in the test environment, you can tweak any of your application's settings specifically for testing.

For example, by default, the Swift Mailer is configured to not actually deliver emails in the test environment. You can see this under the swiftmailer configuration option:

.. configuration-block::

    .. code-block:: yaml

        # config/packages/test/swiftmailer.yaml

        # ...
        swiftmailer:
            disable_delivery: true

    .. code-block:: xml

        <!-- config/packages/test/swiftmailer.xml -->
        <?xml version="1.0" encoding="UTF-8" ?>
        <container xmlns="http://symfony.com/schema/dic/services"
            xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
            xmlns:swiftmailer="http://symfony.com/schema/dic/swiftmailer"
            xsi:schemaLocation="http://symfony.com/schema/dic/services
                https://symfony.com/schema/dic/services/services-1.0.xsd
                http://symfony.com/schema/dic/swiftmailer
                https://symfony.com/schema/dic/swiftmailer/swiftmailer-1.0.xsd">

            <!-- ... -->
            <swiftmailer:config disable-delivery="true"/>
        </container>

    .. code-block:: php

        // config/packages/test/swiftmailer.php

        // ...
        $container->loadFromExtension('swiftmailer', [
            'disable_delivery' => true,
        ]);

You can also use a different environment entirely, or override the default debug mode (true) by passing each as options to the createClient() method:

$client = static::createClient([
    'environment' => 'my_test_env',
    'debug'       => false,
]);

Customizing Database URL / Environment Variables

If you need to customize some environment variables for your tests (e.g. the DATABASE_URL used by Doctrine), you can do that by overriding anything you need in your .env.test file:

# .env.test
DATABASE_URL="mysql://db_user:db_password@127.0.0.1:3306/db_name_test"

# use SQLITE
# DATABASE_URL="sqlite:///%kernel.project_dir%/var/app.db"

This file is automatically read in the test environment: any keys here override the defaults in .env.

Caution!

Applications created before November 2018 had a slightly different system, involving a .env.dist file. For information about upgrading, see: :doc:`configuration/dot-env-changes`.

Sending Custom Headers

If your application behaves according to some HTTP headers, pass them as the second argument of createClient():

$client = static::createClient([], [
    'HTTP_HOST'       => 'en.example.com',
    'HTTP_USER_AGENT' => 'MySuperBrowser/1.0',
]);

You can also override HTTP headers on a per request basis:

$client->request('GET', '/', [], [], [
    'HTTP_HOST'       => 'en.example.com',
    'HTTP_USER_AGENT' => 'MySuperBrowser/1.0',
]);

Tip

The test client is available as a service in the container in the test environment (or wherever the :ref:`framework.test <reference-framework-test>` option is enabled). This means you can override the service entirely if you need to.

.. index::
   pair: PHPUnit; Configuration

PHPUnit Configuration

Each application has its own PHPUnit configuration, stored in the phpunit.xml.dist file. You can edit this file to change the defaults or create a phpunit.xml file to set up a configuration for your local machine only.

Tip

Store the phpunit.xml.dist file in your code repository and ignore the phpunit.xml file.

By default, only the tests stored in tests/ are run via the phpunit command, as configured in the phpunit.xml.dist file:

<!-- phpunit.xml.dist -->
<phpunit>
    <!-- ... -->
    <testsuites>
        <testsuite name="Project Test Suite">
            <directory>tests</directory>
        </testsuite>
    </testsuites>
    <!-- ... -->
</phpunit>

But you can add more directories. For instance, the following configuration adds tests from a custom lib/tests directory:

<!-- phpunit.xml.dist -->
<phpunit>
    <!-- ... -->
    <testsuites>
        <testsuite name="Project Test Suite">
            <!-- ... --->
            <directory>lib/tests</directory>
        </testsuite>
    </testsuites>
    <!-- ... -->
</phpunit>

To include other directories in the code coverage, also edit the <filter> section:

<!-- phpunit.xml.dist -->
<phpunit>
    <!-- ... -->
    <filter>
        <whitelist>
            <!-- ... -->
            <directory>lib</directory>
            <exclude>
                <!-- ... -->
                <directory>lib/tests</directory>
            </exclude>
        </whitelist>
    </filter>
    <!-- ... -->
</phpunit>

Learn more

.. toctree::
    :maxdepth: 1
    :glob:

    testing/*
    /components/dom_crawler
    /components/css_selector