README

A PHP library for checking if attributes are present on classes, properties, methods, parameters, functions, class constants, and enum cases.

Built on top of PHP 8+ Reflection API. Lightweight, zero dependencies.

Requirements

• PHP 8.1+

Installation

composer require damirco/attr

Quick Start

use Damirco\Attr\ClassAttribute;

// 1. Define an attribute
#[\Attribute]
class MyAttribute {}

// 2. Apply it to a class
#[MyAttribute]
class MyClass {}

// 3. Check if it's present
$attribute = new ClassAttribute(MyAttribute::class);
$attribute->isPresentOn(MyClass::class);       // true
$attribute->isPresentOn(new MyClass());        // true (also works with instances)

Usage

Check class attributes

use Damirco\Attr\ClassAttribute;

$attribute = new ClassAttribute(MyAttribute::class);

$attribute->isPresentOn(MyClass::class);       // by class name
$attribute->isPresentOn(new MyClass());        // by instance

Check property attributes

use Damirco\Attr\PropertyAttribute;

$attribute = new PropertyAttribute(MyAttribute::class);

$attribute->isPresentOn(MyClass::class, 'propertyName');

Check method attributes

use Damirco\Attr\MethodAttribute;

$attribute = new MethodAttribute(MyAttribute::class);

$attribute->isPresentOn(MyClass::class, 'methodName');

Check parameter attributes

use Damirco\Attr\ParameterAttribute;

$attribute = new ParameterAttribute(MyAttribute::class);

$attribute->isPresentOn('myFunction', 'paramName');

Check function attributes

use Damirco\Attr\FunctionAttribute;

$attribute = new FunctionAttribute(MyAttribute::class);

$attribute->isPresentOn('myFunction');

Check class constant attributes

use Damirco\Attr\ClassConstantAttribute;

$attribute = new ClassConstantAttribute(MyAttribute::class);

$attribute->isPresentOn(MyClass::class, 'CONSTANT_NAME');

Check enum case attributes

use Damirco\Attr\EnumCaseAttribute;

$attribute = new EnumCaseAttribute(MyAttribute::class);

$attribute->isPresentOn(MyEnum::class, 'CASE_NAME');

How it works

Each class wraps PHP's ReflectionAttribute::getAttributes() method. The library:

1. Creates a Reflection* object for the target (class, property, method, etc.)
2. Calls getAttributes($attributeClass, $flags) on it
3. Returns true if the result is not empty

The $flags parameter controls matching behavior:

• \ReflectionAttribute::IS_INSTANCEOF (default) — matches if the attribute extends the given class
• 0 — exact class match only

// Example: MyAttribute extends BaseAttribute
#[MyAttribute]
class MyClass {}

$attr = new ClassAttribute(BaseAttribute::class);
$attr->isPresentOn(MyClass::class);  // true (IS_INSTANCEOF by default)

$attr = new ClassAttribute(BaseAttribute::class, 0);
$attr->isPresentOn(MyClass::class);  // false (exact match only)

Available classes

Configuration

All classes extend AbstractAttribute and accept two constructor parameters:

new ClassAttribute(
    attribute_class: MyAttribute::class,  // attribute to check for
    flags: \ReflectionAttribute::IS_INSTANCEOF  // matching mode (default)
);

Fluent setters

$attribute = new ClassAttribute(MyAttribute::class)
    ->setAttributeClass(AnotherAttribute::class)
    ->setFlags(0);

Testing

composer test

License

MIT