diff --git a/doc/advanced.rst b/doc/advanced.rst
index bc7e5d376f4..c102fd553a2 100644
--- a/doc/advanced.rst
+++ b/doc/advanced.rst
@@ -813,6 +813,110 @@ The ``getTests()`` method lets you add new test functions::
         // ...
     }
 
+Using PHP Attributes to define Extensions
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+.. versionadded:: 3.19
+
+    The attribute classes were added in Twig 3.19.
+
+You can use the attributes ``#[AsTwigFilter]``, ``#[AsTwigFunction]``, and
+``#[AsTwigTest]`` on any method of any class to define filters, functions, and tests.
+
+Create a class using this attributes::
+
+    use Twig\Attribute\AsTwigFilter;
+    use Twig\Attribute\AsTwigFunction;
+    use Twig\Attribute\AsTwigTest;
+
+    class ProjectExtension
+    {
+        #[AsTwigFilter('rot13')]
+        public static function rot13(string $string): string
+        {
+            // ...
+        }
+
+        #[AsTwigFunction('lipsum')]
+        public static function lipsum(int $count): string
+        {
+            // ...
+        }
+
+        #[AsTwigTest('even')]
+        public static function isEven(int $number): bool
+        {
+            // ...
+        }
+    }
+
+Then register the ``Twig\Extension\AttributeExtension`` with the class name::
+
+    $twig = new \Twig\Environment($loader);
+    $twig->addExtension(new \Twig\Extension\AttributeExtension([
+        // List of all the classes using AsTwig attributes
+        ProjectExtension::class,
+    ]);
+
+If all the methods are static, you are done. The ``ProjectExtension`` class will
+never be instantiated and the class attributes will be scanned only when a template
+is compiled.
+
+Otherwise, if some methods are not static, you need to register the class as
+a runtime extension using one of the runtime loaders::
+
+    use Twig\Attribute\AsTwigFunction;
+
+    class ProjectExtension
+    {
+        // Inject hypothetical dependencies
+        public function __construct(private LipsumProvider $lipsumProvider) {}
+
+        #[AsTwigFunction('lipsum')]
+        public function lipsum(int $count): string
+        {
+            return $this->lipsumProvider->lipsum($count);
+        }
+    }
+
+    $twig = new \Twig\Environment($loader);
+    $twig->addExtension(new \Twig\Extension\AttributeExtension([ProjectExtension::class]);
+    $twig->addRuntimeLoader(new \Twig\RuntimeLoader\FactoryLoader([
+        ProjectExtension::class => function () use ($lipsumProvider) {
+            return new ProjectExtension($lipsumProvider);
+        },
+    ]));
+
+If you want to access the current environment instance in your filter or function,
+add the ``Twig\Environment`` type to the first argument of the method::
+
+    class ProjectExtension
+    {
+        #[AsTwigFunction('lipsum')]
+        public function lipsum(\Twig\Environment $env, int $count): string
+        {
+            // ...
+        }
+    }
+
+``#[AsTwigFilter]`` and ``#[AsTwigFunction]`` support variadic arguments
+automatically when applied to variadic methods::
+
+    class ProjectExtension
+    {
+        #[AsTwigFilter('thumbnail')]
+        public function thumbnail(string $file, mixed ...$options): string
+        {
+            // ...
+        }
+    }
+
+The attributes support other options used to configure the Twig Callables:
+
+ * ``AsTwigFilter``: ``needsCharset``, ``needsEnvironment``, ``needsContext``, ``isSafe``, ``isSafeCallback``, ``preEscape``, ``preservesSafety``, ``deprecationInfo``
+ * ``AsTwigFunction``: ``needsCharset``, ``needsEnvironment``, ``needsContext``, ``isSafe``, ``isSafeCallback``, ``deprecationInfo``
+ * ``AsTwigTest``: ``needsCharset``, ``needsEnvironment``, ``needsContext``, ``deprecationInfo``
+
 Definition vs Runtime
 ~~~~~~~~~~~~~~~~~~~~~
 
diff --git a/src/Attribute/AsTwigFilter.php b/src/Attribute/AsTwigFilter.php
new file mode 100644
index 00000000000..9313bf6cc00
--- /dev/null
+++ b/src/Attribute/AsTwigFilter.php
@@ -0,0 +1,57 @@
+<?php
+
+/*
+ * This file is part of Twig.
+ *
+ * (c) Fabien Potencier
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Twig\Attribute;
+
+use Twig\DeprecatedCallableInfo;
+use Twig\TwigFilter;
+
+/**
+ * Registers a method as template filter.
+ *
+ * If the first argument of the method has Twig\Environment type-hint, the filter will receive the current environment.
+ * If the next argument of the method is named $context and has array type-hint, the filter will receive the current context.
+ * Additional arguments of the method come from the filter call.
+ *
+ *     #[AsTwigFilter('foo')]
+ *     function fooFilter(Environment $env, array $context, $string, $arg1 = null, ...) { ... }
+ *
+ *    {{ 'string'|foo(arg1) }}
+ *
+ * @see TwigFilter
+ */
+#[\Attribute(\Attribute::TARGET_METHOD | \Attribute::IS_REPEATABLE)]
+final class AsTwigFilter
+{
+    /**
+     * @param non-empty-string $name The name of the filter in Twig.
+     * @param bool|null $needsCharset Whether the filter needs the charset passed as the first argument.
+     * @param bool|null $needsEnvironment Whether the filter needs the environment passed as the first argument, or after the charset.
+     * @param bool|null $needsContext Whether the filter needs the context array passed as the first argument, or after the charset and the environment.
+     * @param string[]|null $isSafe List of formats in which you want the raw output to be printed unescaped.
+     * @param string|array|null $isSafeCallback Function called at compilation time to determine if the filter is safe.
+     * @param string|null $preEscape Some filters may need to work on input that is already escaped or safe
+     * @param string[]|null $preservesSafety Preserves the safety of the value that the filter is applied to.
+     * @param DeprecatedCallableInfo|null $deprecationInfo Information about the deprecation
+     */
+    public function __construct(
+        public string $name,
+        public ?bool $needsCharset = null,
+        public ?bool $needsEnvironment = null,
+        public ?bool $needsContext = null,
+        public ?array $isSafe = null,
+        public string|array|null $isSafeCallback = null,
+        public ?string $preEscape = null,
+        public ?array $preservesSafety = null,
+        public ?DeprecatedCallableInfo $deprecationInfo = null,
+    ) {
+    }
+}
diff --git a/src/Attribute/AsTwigFunction.php b/src/Attribute/AsTwigFunction.php
new file mode 100644
index 00000000000..551c4c874cc
--- /dev/null
+++ b/src/Attribute/AsTwigFunction.php
@@ -0,0 +1,53 @@
+<?php
+
+/*
+ * This file is part of Twig.
+ *
+ * (c) Fabien Potencier
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Twig\Attribute;
+
+use Twig\DeprecatedCallableInfo;
+use Twig\TwigFunction;
+
+/**
+ * Registers a method as template function.
+ *
+ * If the first argument of the method has Twig\Environment type-hint, the function will receive the current environment.
+ * If the next argument of the method is named $context and has array type-hint, the function will receive the current context.
+ * Additional arguments of the method come from the function call.
+ *
+ *     #[AsTwigFunction('foo')]
+ *     function fooFunction(Environment $env, array $context, string $string, $arg1 = null, ...) { ... }
+ *
+ *     {{ foo('string', arg1) }}
+ *
+ * @see TwigFunction
+ */
+#[\Attribute(\Attribute::TARGET_METHOD | \Attribute::IS_REPEATABLE)]
+final class AsTwigFunction
+{
+    /**
+     * @param non-empty-string $name The name of the function in Twig.
+     * @param bool|null $needsCharset Whether the function needs the charset passed as the first argument.
+     * @param bool|null $needsEnvironment Whether the function needs the environment passed as the first argument, or after the charset.
+     * @param bool|null $needsContext Whether the function needs the context array passed as the first argument, or after the charset and the environment.
+     * @param string[]|null $isSafe List of formats in which you want the raw output to be printed unescaped.
+     * @param string|array|null $isSafeCallback Function called at compilation time to determine if the function is safe.
+     * @param DeprecatedCallableInfo|null $deprecationInfo Information about the deprecation
+     */
+    public function __construct(
+        public string $name,
+        public ?bool $needsCharset = null,
+        public ?bool $needsEnvironment = null,
+        public ?bool $needsContext = null,
+        public ?array $isSafe = null,
+        public string|array|null $isSafeCallback = null,
+        public ?DeprecatedCallableInfo $deprecationInfo = null,
+    ) {
+    }
+}
diff --git a/src/Attribute/AsTwigTest.php b/src/Attribute/AsTwigTest.php
new file mode 100644
index 00000000000..57dd267790e
--- /dev/null
+++ b/src/Attribute/AsTwigTest.php
@@ -0,0 +1,48 @@
+<?php
+
+/*
+ * This file is part of Twig.
+ *
+ * (c) Fabien Potencier
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Twig\Attribute;
+
+use Twig\DeprecatedCallableInfo;
+use Twig\TwigTest;
+
+/**
+ * Registers a method as template test.
+ *
+ * The first argument is the value to test and the other arguments are the
+ * arguments passed to the test in the template.
+ *
+ *     #[AsTwigTest('foo')]
+ *     public function fooTest($value, $arg1 = null) { ... }
+ *
+ *     {% if value is foo(arg1) %}
+ *
+ * @see TwigTest
+ */
+#[\Attribute(\Attribute::TARGET_METHOD | \Attribute::IS_REPEATABLE)]
+final class AsTwigTest
+{
+    /**
+     * @param non-empty-string $name The name of the test in Twig.
+     * @param bool|null $needsCharset Whether the test needs the charset passed as the first argument.
+     * @param bool|null $needsEnvironment Whether the test needs the environment passed as the first argument, or after the charset.
+     * @param bool|null $needsContext Whether the test needs the context array passed as the first argument, or after the charset and the environment.
+     * @param DeprecatedCallableInfo|null $deprecationInfo Information about the deprecation
+     */
+    public function __construct(
+        public string $name,
+        public ?bool $needsCharset = null,
+        public ?bool $needsEnvironment = null,
+        public ?bool $needsContext = null,
+        public ?DeprecatedCallableInfo $deprecationInfo = null,
+    ) {
+    }
+}
diff --git a/src/Extension/AttributeExtension.php b/src/Extension/AttributeExtension.php
new file mode 100644
index 00000000000..c243ebffb25
--- /dev/null
+++ b/src/Extension/AttributeExtension.php
@@ -0,0 +1,174 @@
+<?php
+
+/*
+ * This file is part of Twig.
+ *
+ * (c) Fabien Potencier
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Twig\Extension;
+
+use Twig\Attribute\AsTwigFilter;
+use Twig\Attribute\AsTwigFunction;
+use Twig\Attribute\AsTwigTest;
+use Twig\Environment;
+use Twig\TwigFilter;
+use Twig\TwigFunction;
+use Twig\TwigTest;
+
+/**
+ * Define Twig filters, functions, and tests with PHP attributes.
+ *
+ * @author Jérôme Tamarelle <jerome@tamarelle.net>
+ */
+final class AttributeExtension extends AbstractExtension
+{
+    private array $filters;
+    private array $functions;
+    private array $tests;
+
+    /**
+     * Use a runtime class using PHP attributes to define filters, functions, and tests.
+     *
+     * @param class-string $class
+     */
+    public function __construct(private string $class)
+    {
+    }
+
+    /**
+     * @return class-string
+     */
+    public function getClass(): string
+    {
+        return $this->class;
+    }
+
+    public function getFilters(): array
+    {
+        if (!isset($this->filters)) {
+            $this->initFromAttributes();
+        }
+
+        return $this->filters;
+    }
+
+    public function getFunctions(): array
+    {
+        if (!isset($this->functions)) {
+            $this->initFromAttributes();
+        }
+
+        return $this->functions;
+    }
+
+    public function getTests(): array
+    {
+        if (!isset($this->tests)) {
+            $this->initFromAttributes();
+        }
+
+        return $this->tests;
+    }
+
+    public function getLastModified(): int
+    {
+        return max(
+            filemtime(__FILE__),
+            is_file($filename = (new \ReflectionClass($this->class))->getFileName()) ? filemtime($filename) : 0,
+        );
+    }
+
+    private function initFromAttributes(): void
+    {
+        $filters = $functions = $tests = [];
+        $reflectionClass = new \ReflectionClass($this->class);
+        foreach ($reflectionClass->getMethods() as $method) {
+            foreach ($method->getAttributes(AsTwigFilter::class) as $reflectionAttribute) {
+                /** @var AsTwigFilter $attribute */
+                $attribute = $reflectionAttribute->newInstance();
+
+                $callable = new TwigFilter($attribute->name, [$this->class, $method->getName()], [
+                    'needs_context' => $attribute->needsContext ?? false,
+                    'needs_environment' => $attribute->needsEnvironment ?? $this->needsEnvironment($method),
+                    'needs_charset' => $attribute->needsCharset ?? false,
+                    'is_variadic' => $method->isVariadic(),
+                    'is_safe' => $attribute->isSafe,
+                    'is_safe_callback' => $attribute->isSafeCallback,
+                    'pre_escape' => $attribute->preEscape,
+                    'preserves_safety' => $attribute->preservesSafety,
+                    'deprecation_info' => $attribute->deprecationInfo,
+                ]);
+
+                if ($callable->getMinimalNumberOfRequiredArguments() > $method->getNumberOfParameters()) {
+                    throw new \LogicException(sprintf('"%s::%s()" needs at least %d arguments to be used AsTwigFilter, but only %d defined.', $reflectionClass->getName(), $method->getName(), $callable->getMinimalNumberOfRequiredArguments(), $method->getNumberOfParameters()));
+                }
+
+                $filters[$attribute->name] = $callable;
+            }
+
+            foreach ($method->getAttributes(AsTwigFunction::class) as $reflectionAttribute) {
+                /** @var AsTwigFunction $attribute */
+                $attribute = $reflectionAttribute->newInstance();
+
+                $callable = new TwigFunction($attribute->name, [$this->class, $method->getName()], [
+                    'needs_context' => $attribute->needsContext ?? false,
+                    'needs_environment' => $attribute->needsEnvironment ?? $this->needsEnvironment($method),
+                    'needs_charset' => $attribute->needsCharset ?? false,
+                    'is_variadic' => $method->isVariadic(),
+                    'is_safe' => $attribute->isSafe,
+                    'is_safe_callback' => $attribute->isSafeCallback,
+                    'deprecation_info' => $attribute->deprecationInfo,
+                ]);
+
+                if ($callable->getMinimalNumberOfRequiredArguments() > $method->getNumberOfParameters()) {
+                    throw new \LogicException(sprintf('"%s::%s()" needs at least %d arguments to be used AsTwigFunction, but only %d defined.', $reflectionClass->getName(), $method->getName(), $callable->getMinimalNumberOfRequiredArguments(), $method->getNumberOfParameters()));
+                }
+
+                $functions[$attribute->name] = $callable;
+            }
+
+            foreach ($method->getAttributes(AsTwigTest::class) as $reflectionAttribute) {
+
+                /** @var AsTwigTest $attribute */
+                $attribute = $reflectionAttribute->newInstance();
+
+                $callable = new TwigTest($attribute->name, [$this->class, $method->getName()], [
+                    'needs_context' => $attribute->needsContext ?? false,
+                    'needs_environment' => $attribute->needsEnvironment ?? $this->needsEnvironment($method),
+                    'needs_charset' => $attribute->needsCharset ?? false,
+                    'is_variadic' => $method->isVariadic(),
+                    'deprecation_info' => $attribute->deprecationInfo,
+                ]);
+
+                if ($callable->getMinimalNumberOfRequiredArguments() > $method->getNumberOfParameters()) {
+                    throw new \LogicException(sprintf('"%s::%s()" needs at least %d arguments to be used AsTwigTest, but only %d defined.', $reflectionClass->getName(), $method->getName(), $callable->getMinimalNumberOfRequiredArguments(), $method->getNumberOfParameters()));
+                }
+
+                $tests[$attribute->name] = $callable;
+            }
+        }
+
+        // Assign all at the end to avoid inconsistent state in case of exception
+        $this->filters = array_values($filters);
+        $this->functions = array_values($functions);
+        $this->tests = array_values($tests);
+    }
+
+    /**
+     * Detect if the first argument of the method is the environment.
+     */
+    private function needsEnvironment(\ReflectionFunctionAbstract $function): bool
+    {
+        if (!$parameters = $function->getParameters()) {
+            return false;
+        }
+
+        return $parameters[0]->getType() instanceof \ReflectionNamedType
+            && Environment::class === $parameters[0]->getType()->getName()
+            && !$parameters[0]->isVariadic();
+    }
+}
diff --git a/src/ExtensionSet.php b/src/ExtensionSet.php
index 18979228a7d..e567ed52325 100644
--- a/src/ExtensionSet.php
+++ b/src/ExtensionSet.php
@@ -12,6 +12,7 @@
 namespace Twig;
 
 use Twig\Error\RuntimeError;
+use Twig\Extension\AttributeExtension;
 use Twig\Extension\ExtensionInterface;
 use Twig\Extension\GlobalsInterface;
 use Twig\Extension\LastModifiedExtensionInterface;
@@ -134,7 +135,11 @@ public function getLastModified(): int
 
     public function addExtension(ExtensionInterface $extension): void
     {
-        $class = \get_class($extension);
+        if ($extension instanceof AttributeExtension) {
+            $class = $extension->getClass();
+        } else {
+            $class = \get_class($extension);
+        }
 
         if ($this->initialized) {
             throw new \LogicException(\sprintf('Unable to register extension "%s" as extensions have already been initialized.', $class));
diff --git a/tests/Extension/AttributeExtensionTest.php b/tests/Extension/AttributeExtensionTest.php
new file mode 100644
index 00000000000..26c5f10bbe5
--- /dev/null
+++ b/tests/Extension/AttributeExtensionTest.php
@@ -0,0 +1,164 @@
+<?php
+
+namespace Twig\Tests\Extension;
+
+use PHPUnit\Framework\TestCase;
+use Twig\DeprecatedCallableInfo;
+use Twig\Error\RuntimeError;
+use Twig\Extension\AttributeExtension;
+use Twig\ExtensionSet;
+use Twig\Tests\Extension\Fixtures\FilterWithoutValue;
+use Twig\Tests\Extension\Fixtures\TestWithoutValue;
+use Twig\Tests\Extension\Fixtures\ExtensionWithAttributes;
+use Twig\TwigFilter;
+use Twig\TwigFunction;
+use Twig\TwigTest;
+
+/**
+ * Nested attributes are not supported in PHP 8.0.
+ * @requires PHP >= 8.1
+ */
+class AttributeExtensionTest extends TestCase
+{
+    /**
+     * @dataProvider provideFilters
+     */
+    public function testFilter(string $name, string $method, array $options)
+    {
+        $extension = new AttributeExtension(ExtensionWithAttributes::class);
+        foreach ($extension->getFilters() as $filter) {
+            if ($filter->getName() === $name) {
+                $this->assertEquals(new TwigFilter($name, [ExtensionWithAttributes::class, $method], $options), $filter);
+
+                return;
+            }
+        }
+
+        $this->fail(sprintf('Filter "%s" is not registered.', $name));
+    }
+
+    public static function provideFilters()
+    {
+        yield 'with name' => ['foo', 'fooFilter', ['is_safe' => ['html']]];
+        yield 'with env' => ['with_env_filter', 'withEnvFilter', ['needs_environment' => true]];
+        yield 'with context' => ['with_context_filter', 'withContextFilter', ['needs_context' => true]];
+        yield 'with env and context' => ['with_env_and_context_filter', 'withEnvAndContextFilter', ['needs_environment' => true, 'needs_context' => true]];
+        yield 'variadic' => ['variadic_filter', 'variadicFilter', ['is_variadic' => true]];
+        yield 'deprecated' => ['deprecated_filter', 'deprecatedFilter', ['deprecation_info' => new DeprecatedCallableInfo('foo/bar', '1.2')]];
+        yield 'pattern' => ['pattern_*_filter', 'patternFilter', []];
+    }
+
+    /**
+     * @dataProvider provideFunctions
+     */
+    public function testFunction(string $name, string $method, array $options)
+    {
+        $extension = new AttributeExtension(ExtensionWithAttributes::class);
+        foreach ($extension->getFunctions() as $function) {
+            if ($function->getName() === $name) {
+                $this->assertEquals(new TwigFunction($name, [ExtensionWithAttributes::class, $method], $options), $function);
+
+                return;
+            }
+        }
+
+        $this->fail(sprintf('Function "%s" is not registered.', $name));
+    }
+
+    public static function provideFunctions()
+    {
+        yield 'with name' => ['foo', 'fooFunction', ['is_safe' => ['html']]];
+        yield 'with env' => ['with_env_function', 'withEnvFunction', ['needs_environment' => true]];
+        yield 'with context' => ['with_context_function', 'withContextFunction', ['needs_context' => true]];
+        yield 'with env and context' => ['with_env_and_context_function', 'withEnvAndContextFunction', ['needs_environment' => true, 'needs_context' => true]];
+        yield 'no argument' => ['no_arg_function', 'noArgFunction', []];
+        yield 'variadic' => ['variadic_function', 'variadicFunction', ['is_variadic' => true]];
+        yield 'deprecated' => ['deprecated_function', 'deprecatedFunction', ['deprecation_info' => new DeprecatedCallableInfo('foo/bar', '1.2')]];
+    }
+
+    /**
+     * @dataProvider provideTests
+     */
+    public function testTest(string $name, string $method, array $options)
+    {
+        $extension = new AttributeExtension(ExtensionWithAttributes::class);
+        foreach ($extension->getTests() as $test) {
+            if ($test->getName() === $name) {
+                $this->assertEquals(new TwigTest($name, [ExtensionWithAttributes::class, $method], $options), $test);
+
+                return;
+            }
+        }
+
+        $this->fail(sprintf('Test "%s" is not registered.', $name));
+    }
+
+    public static function provideTests()
+    {
+        yield 'with name' => ['foo', 'fooTest', []];
+        yield 'with env' => ['with_env_test', 'withEnvTest', ['needs_environment' => true]];
+        yield 'with context' => ['with_context_test', 'withContextTest', ['needs_context' => true]];
+        yield 'with env and context' => ['with_env_and_context_test', 'withEnvAndContextTest', ['needs_environment' => true, 'needs_context' => true]];
+        yield 'variadic' => ['variadic_test', 'variadicTest', ['is_variadic' => true]];
+        yield 'deprecated' => ['deprecated_test', 'deprecatedTest', ['deprecation_info' => new DeprecatedCallableInfo('foo/bar', '1.2')]];
+    }
+
+    public function testFilterRequireOneArgument()
+    {
+        $extension = new AttributeExtension(FilterWithoutValue::class);
+
+        $this->expectException(\LogicException::class);
+        $this->expectExceptionMessage('"'.FilterWithoutValue::class.'::myFilter()" needs at least 1 arguments to be used AsTwigFilter, but only 0 defined.');
+
+        $extension->getTests();
+    }
+
+    public function testTestRequireOneArgument()
+    {
+        $extension = new AttributeExtension(TestWithoutValue::class);
+
+        $this->expectException(\LogicException::class);
+        $this->expectExceptionMessage('"'.TestWithoutValue::class.'::myTest()" needs at least 1 arguments to be used AsTwigTest, but only 0 defined.');
+
+        $extension->getTests();
+    }
+
+    public function testLastModifiedWithObject()
+    {
+        $extension = new AttributeExtension(\stdClass::class);
+
+        $this->assertSame(filemtime((new \ReflectionClass(AttributeExtension::class))->getFileName()), $extension->getLastModified());
+    }
+
+    public function testLastModifiedWithClass()
+    {
+        $extension = new AttributeExtension('__CLASS_FOR_TEST_LAST_MODIFIED__');
+
+        $filename = tempnam(sys_get_temp_dir(), 'twig');
+        try {
+            file_put_contents($filename, '<?php class __CLASS_FOR_TEST_LAST_MODIFIED__ {}');
+            require $filename;
+
+            $this->assertSame(filemtime($filename), $extension->getLastModified());
+        } finally {
+            unlink($filename);
+        }
+    }
+
+    public function testMultipleRegistrations()
+    {
+        $extensionSet = new ExtensionSet();
+        $extensionSet->addExtension($extension1 = new AttributeExtension(ExtensionWithAttributes::class));
+        $extensionSet->addExtension($extension2 = new AttributeExtension(\stdClass::class));
+
+        $this->assertCount(2, $extensionSet->getExtensions());
+        $this->assertNotNull($extensionSet->getFilter('foo'));
+
+        $this->assertSame($extension1, $extensionSet->getExtension(ExtensionWithAttributes::class));
+        $this->assertSame($extension2, $extensionSet->getExtension(\stdClass::class));
+
+        $this->expectException(RuntimeError::class);
+        $this->expectExceptionMessage('The "Twig\Extension\AttributeExtension" extension is not enabled.');
+        $extensionSet->getExtension(AttributeExtension::class);
+    }
+}
diff --git a/tests/Extension/Fixtures/ExtensionWithAttributes.php b/tests/Extension/Fixtures/ExtensionWithAttributes.php
new file mode 100644
index 00000000000..2e6b0ee1011
--- /dev/null
+++ b/tests/Extension/Fixtures/ExtensionWithAttributes.php
@@ -0,0 +1,112 @@
+<?php
+
+namespace Twig\Tests\Extension\Fixtures;
+
+use Twig\Attribute\AsTwigFilter;
+use Twig\Attribute\AsTwigFunction;
+use Twig\Attribute\AsTwigTest;
+use Twig\DeprecatedCallableInfo;
+use Twig\Environment;
+
+class ExtensionWithAttributes
+{
+    #[AsTwigFilter(name: 'foo', isSafe: ['html'])]
+    public function fooFilter(string|int $string)
+    {
+    }
+
+    #[AsTwigFilter('with_context_filter', needsContext: true)]
+    public function withContextFilter(array $context, string $string)
+    {
+    }
+
+    #[AsTwigFilter('with_env_filter')]
+    public function withEnvFilter(Environment $env, string $string)
+    {
+    }
+
+    #[AsTwigFilter('with_env_and_context_filter', needsContext: true)]
+    public function withEnvAndContextFilter(Environment $env, array $context, array $data)
+    {
+    }
+
+    #[AsTwigFilter('variadic_filter')]
+    public function variadicFilter(string ...$strings)
+    {
+    }
+
+    #[AsTwigFilter('deprecated_filter', deprecationInfo: new DeprecatedCallableInfo('foo/bar', '1.2'))]
+    public function deprecatedFilter(string $string)
+    {
+    }
+
+    #[AsTwigFilter('pattern_*_filter')]
+    public function patternFilter(string $string)
+    {
+    }
+
+    #[AsTwigFunction(name: 'foo', isSafe: ['html'])]
+    public function fooFunction(string|int $string)
+    {
+    }
+
+    #[AsTwigFunction('with_context_function', needsContext: true)]
+    public function withContextFunction(array $context, string $string)
+    {
+    }
+
+    #[AsTwigFunction('with_env_function')]
+    public function withEnvFunction(Environment $env, string $string)
+    {
+    }
+
+    #[AsTwigFunction('with_env_and_context_function', needsContext: true)]
+    public function withEnvAndContextFunction(Environment $env, array $context, string $string)
+    {
+    }
+
+    #[AsTwigFunction('no_arg_function')]
+    public function noArgFunction()
+    {
+    }
+
+    #[AsTwigFunction('variadic_function')]
+    public function variadicFunction(string ...$strings)
+    {
+    }
+
+    #[AsTwigFunction('deprecated_function', deprecationInfo: new DeprecatedCallableInfo('foo/bar', '1.2'))]
+    public function deprecatedFunction(string $string)
+    {
+    }
+
+    #[AsTwigTest(name: 'foo')]
+    public function fooTest(string|int $value)
+    {
+    }
+
+    #[AsTwigTest('variadic_test')]
+    public function variadicTest(string ...$value)
+    {
+    }
+
+    #[AsTwigTest('with_context_test', needsContext: true)]
+    public function withContextTest(array $context, $argument)
+    {
+    }
+
+    #[AsTwigTest('with_env_test')]
+    public function withEnvTest(Environment $env, $argument)
+    {
+    }
+
+    #[AsTwigTest('with_env_and_context_test', needsContext: true)]
+    public function withEnvAndContextTest(Environment $env, array $context, $argument)
+    {
+    }
+
+    #[AsTwigTest('deprecated_test', deprecationInfo: new DeprecatedCallableInfo('foo/bar', '1.2'))]
+    public function deprecatedTest($value, $argument)
+    {
+    }
+}
diff --git a/tests/Extension/Fixtures/FilterWithoutValue.php b/tests/Extension/Fixtures/FilterWithoutValue.php
new file mode 100644
index 00000000000..a59efb55c1b
--- /dev/null
+++ b/tests/Extension/Fixtures/FilterWithoutValue.php
@@ -0,0 +1,13 @@
+<?php
+
+namespace Twig\Tests\Extension\Fixtures;
+
+use Twig\Attribute\AsTwigFilter;
+
+class FilterWithoutValue
+{
+    #[AsTwigFilter('my_filter')]
+    public function myFilter()
+    {
+    }
+}
diff --git a/tests/Extension/Fixtures/TestWithoutValue.php b/tests/Extension/Fixtures/TestWithoutValue.php
new file mode 100644
index 00000000000..139f7852a06
--- /dev/null
+++ b/tests/Extension/Fixtures/TestWithoutValue.php
@@ -0,0 +1,13 @@
+<?php
+
+namespace Twig\Tests\Extension\Fixtures;
+
+use Twig\Attribute\AsTwigTest;
+
+class TestWithoutValue
+{
+    #[AsTwigTest('my_test')]
+    public function myTest()
+    {
+    }
+}