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docs/source/development/code-quality.md

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+# Code style, code quality and other tools
+
+## PHP-cs-fixer
+
+For development, you will also have to install:
+
+- [php-cs-fixer ](https://cs.symfony.com/)
+
+We also encourage you to use tools like [phpstan ](https://phpstan.org) and [rector ](https://getrector.com).
+
+For running php-cs-fixer:
+
+   symfony composer php-cs-fixer
+
+## Execute tests
+
+   symfony composer exec phpunit -- /path/to_your_test.php
+
+Note that IDE like PhpStorm should be able to run tests, even KernelTestcase or WebTestCase, [from within their interfaces ](https://www.jetbrains.com/help/phpstorm/using-phpunit-framework.html#run_phpunit_tests).
+
+## Execute rector
+
+   symfony composer exec rector -- process