How does Symfony load the test environment for end-to-end tests?

user_1196369 0
Viewed 1259

I'm working on another PHP project that uses end-to-end tests and .env files. However before running the tests I need to modify the .env file to point to the test database (instead of the development one). When I work on Symfony projects I don't believe I need to do that, it just loads the test environment automatically.

I know from some previous experience with older versions that there used to be a different front controller for each environment, like app.php, app_dev.php etc. but afaik that isn't the case now.

How does Symfony know to load the test environment for end-to-end tests?

symfony phpunit php
2 Answers

The flex recipe for the phpunit-bridge includes a phpunit.xml file that sets the APP_ENV variable to test. That triggers symfony to load the appropiate .env.test file.

During tests the front controller isn't normally used, as the bridge instantiates a Request object and passes it to the application kernel directly. But in end-to-end tests using PantherTestCase, the framework boots the project in the built-in PHP webserver, which is still controlled by environment variables.

This is better explained in the book than the testing chapter of the documentation itself:

The $client variable simulates a browser. Instead of making HTTP calls to the server though, it calls the Symfony application directly. This strategy has several benefits: it is much faster than having round-trips between the client and the server, but it also allows the tests to introspect the state of the services after each HTTP request.

And in the Panther announcement:

However, WebTestCase doesn’t use a real web browser. It simulates one with pure PHP components. It doesn’t even use the HTTP protocol: it creates instances of HttpFoundation’s Request objects, pass them to the Symfony kernel, and allows to assert on the HttpFoundation Response instance returned by the app.
[...]
Under the hood Panther has:

  • started your project with the built-in PHP webserver on localhost:9000
  • started the version of Chromedriver shipped with the library to automate your local Chrome
  • executed the browsing scenario defined in the test with Chrome in headless mode
user_47821690

Which environment to use is generally set in phpunit.xml.dist.

This is more a PhpUnit thing than a Symfony one.

You should have an entry like:

<php>
    <server name="APP_ENV" value="test" force="true" />
<!-- ... -->
</php>

By using force=true, it will override the value of any existing APP_ENV environment variable.

WebTestCase will "simulate" the requests, as explained here. If you use something like Panther, the tests will fire up an internal web server and make "real" HTTP requests, as explained here.

In either case, the APP_ENV used by the application is the one defined on PhpUnit configuration.

user_14265390
Related