[TwigBundle] Enable #[AsTwigFilter], #[AsTwigFunction] and #[AsTwigTest]

Author: RisingSunLight42

quick_tour/the_architecture.rst

@@ -159,29 +159,22 @@ Twig Extension & Autoconfiguration
 Thanks to Symfony's service handling, you can *extend* Symfony in many ways, like
 by creating an event subscriber or a security voter for complex authorization
 rules. Let's add a new filter to Twig called ``greet``. How? Create a class
-that extends ``AbstractExtension``::
+with your logic::
 
     // src/Twig/GreetExtension.php
     namespace App\Twig;
 
     use App\GreetingGenerator;
-    use Twig\Extension\AbstractExtension;
-    use Twig\TwigFilter;
+    use Twig\Attribute\AsTwigFilter;
 
-    class GreetExtension extends AbstractExtension
+    class GreetExtension
     {
         public function __construct(
             private GreetingGenerator $greetingGenerator,
         ) {
         }
 
-        public function getFilters(): array
-        {
-            return [
-                new TwigFilter('greet', [$this, 'greetUser']),
-            ];
-        }
-
+        #[AsTwigFilter('greet')]
         public function greetUser(string $name): string
         {
             $greeting =  $this->greetingGenerator->getRandomGreeting();
@@ -197,8 +190,8 @@ After creating just *one* file, you can use this immediately:
     {# templates/default/index.html.twig #}
     {# Will print something like "Hey Symfony!" #}
     <h1>{{ name|greet }}</h1>
-
-How does this work? Symfony notices that your class extends ``AbstractExtension``
+    
+How does this work? Symfony notices that your class uses a Twig attribute
 and so *automatically* registers it as a Twig extension. This is called autoconfiguration,
 and it works for *many* many things. Create a class and then extend a base class
 (or implement an interface). Symfony takes care of the rest.

reference/attributes.rst

@@ -123,6 +123,8 @@ Twig
 ~~~~
 
 * :ref:`Template <templates-template-attribute>`
+* :ref:`AsTwigFilter <templates-twig-filter-attribute>`
+* :ref:`AsTwigFunction <templates-twig-function-attribute>`
 
 Symfony UX
 ~~~~~~~~~~

templates.rst

@@ -1553,23 +1553,20 @@ as currency:
     {# pass in the 3 optional arguments #}
     {{ product.price|price(2, ',', '.') }}
 
-Create a class that extends ``AbstractExtension`` and fill in the logic::
+.. _templates-twig-filter-attribute:
+
+Create a class with a method that contains the filter logic, then add
+the ``#[AsTwigFilter]`` attribute to define the name and options of
+the Twig filter::
 
     // src/Twig/AppExtension.php
     namespace App\Twig;
 
-    use Twig\Extension\AbstractExtension;
-    use Twig\TwigFilter;
+    use Twig\Attribute\AsTwigFilter;
 
-    class AppExtension extends AbstractExtension
+    class AppExtension
     {
-        public function getFilters(): array
-        {
-            return [
-                new TwigFilter('price', [$this, 'formatPrice']),
-            ];
-        }
-
+        #[AsTwigFilter('price')]
         public function formatPrice(float $number, int $decimals = 0, string $decPoint = '.', string $thousandsSep = ','): string
         {
             $price = number_format($number, $decimals, $decPoint, $thousandsSep);
@@ -1579,24 +1576,19 @@ Create a class that extends ``AbstractExtension`` and fill in the logic::
         }
     }
 
-If you want to create a function instead of a filter, define the
-``getFunctions()`` method::
+.. _templates-twig-function-attribute:
+
+If you want to create a function instead of a filter, use the
+``#[AsTwigFunction]`` attribute::
 
     // src/Twig/AppExtension.php
     namespace App\Twig;
 
-    use Twig\Extension\AbstractExtension;
-    use Twig\TwigFunction;
+    use Twig\Attribute\AsTwigFunction;
 
-    class AppExtension extends AbstractExtension
+    class AppExtension
     {
-        public function getFunctions(): array
-        {
-            return [
-                new TwigFunction('area', [$this, 'calculateArea']),
-            ];
-        }
-
+        #[AsTwigFunction('area')]
         public function calculateArea(int $width, int $length): int
         {
             return $width * $length;
@@ -1608,6 +1600,16 @@ If you want to create a function instead of a filter, define the
     Along with custom filters and functions, you can also register
     `global variables`_.
 
+.. versionadded:: 7.3
+
+    Support for the ``#[AsTwigFilter]``, ``#[AsTwigFunction]`` and ``#[AsTwigTest]`` attributes was introduced in Symfony 7.3.
+    Previously, you had to extend the ``AbstractExtension`` class, and override the
+    ``getFilters()`` and ``getFunctions()`` methods.
+
+When using autoconfiguration, the tag ``twig.attribute_extension`` is added automatically
+when a Twig attribute is used on a method of a class. Otherwise, when autoconfiguration is not enabled,
+it needs to be added in the service definition.
+
 Register an Extension as a Service
 ..................................
 
@@ -1631,10 +1633,10 @@ this command to confirm that your new filter was successfully registered:
 Creating Lazy-Loaded Twig Extensions
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 
-Including the code of the custom filters/functions in the Twig extension class
-is the simplest way to create extensions. However, Twig must initialize all
-extensions before rendering any template, even if the template doesn't use an
-extension.
+When using attributes to extend Twig, the services are initialized only when
+the functions or filters are used to render the template. But in case you use the
+classic approach by extending the ``AbstractExtension`` class, Twig initializes all the extensions before
+rendering any template, even if the extension is not used in the template.
 
 If extensions don't define dependencies (i.e. if you don't inject services in
 them) performance is not affected. However, if extensions define lots of complex