Nicolas Grekas
Contributed by Nicolas Grekas in #13398

In computer science, the bridge pattern is meant to "decouple an abstraction from its implementation so that the two can vary independently". The bridge uses encapsulation, aggregation and can use inheritance to separate responsibilities into different classes.

Symfony defines several bridges to abstract third-party libraries such as Doctrine, Monolog, Swiftmailer and Twig. In Symfony 2.7 we added a new bridge for PHPUnit. This first version of the bridge provides the following features:

  • It disables PHP's garbage collector for tests to avoid segmentation faults;
  • It auto registers the needed classes to load Doctrine annotations;
  • It reports a summary of deprecation notices at the end of the test suite.

The last feature is very useful for Symfony developers that are preparing the transition to Symfony 3. First, install the new PHPUnit bridge in your application executing the following command:

1
$ composer require --dev "symfony/phpunit-bridge":2.7.x@beta

Then, execute the test suite and you'll see a report of the deprecated Symfony features that your application is still using:

Symfony PHPUnit Bridge deprecations summary

By default, deprecation notices will make tests fail. This behavior can be controlled with the SYMFONY_DEPRECATIONS_HELPER environment variable (default value = strict). Change the value of that variable to weak to make the bridge ignore deprecation notices. This is useful for projects that must use deprecated interfaces for backward compatibility reasons.

In addition, you can safely mark a test as legacy using any of the following methods:

  • Make its class start with the Legacy prefix;
  • Make its method start with testLegacy;
  • Make its data provider start with provideLegacy or getLegacy;
  • Add the @group legacy annotation to its class or method.
Published in #Living on the edge