==================== Rule ``final_class`` ==================== All classes must be final, except abstract ones and Doctrine entities. Description ----------- No exception and no configuration are intentional. Beside Doctrine entities and of course abstract classes, there is no single reason not to declare all classes final. If you want to subclass a class, mark the parent class as abstract and create two child classes, one empty if necessary: you'll gain much more fine grained type-hinting. If you need to mock a standalone class, create an interface, or maybe it's a value-object that shouldn't be mocked at all. If you need to extend a standalone class, create an interface and use the Composite pattern. If these rules are too strict for you, you can use ``FinalInternalClassFixer`` instead. Warning ------- Using this rule is risky ~~~~~~~~~~~~~~~~~~~~~~~~ Risky when subclassing non-abstract classes. Examples -------- Example #1 ~~~~~~~~~~ .. code-block:: diff --- Original +++ New `_ - Test class: `PhpCsFixer\\Tests\\Fixer\\ClassNotation\\FinalClassFixerTest <./../../../tests/Fixer/ClassNotation/FinalClassFixerTest.php>`_ The test class defines officially supported behaviour. Each test case is a part of our backward compatibility promise.