PHP 8.3: ReflectionMethod::__construct() replacement

Related to #1589

Analysis

Recap of existing PHP 8.2 behavior based on the RFC:

class ReflectionMethod
{
    // Signature 1: called with exactly 2 arguments.
    public function __construct(object|string $objectOrClass, string $method) {}
    
    // Signature 2: called with exactly 1 argument.
    public function __construct(string $classMethod) {}
}

Updated behavior for each version:

class ReflectionMethod
{
    // Signature 1: unchanged behavior
    public function __construct(object|string $objectOrClass, string $method) {}

    // Signature 2: deprecated in 8.4, removed in a future (TBD) major version.
    public function __construct(string $classMethod) {}
 
    // Named constructor: replaces signature 2, added in PHP 8.3
    public static function createFromMethodName(string $method): static {}
}

Top 2000

Found several uses of the deprecated constructor. Examples:

dedoc/scramble:

$reflection = new ReflectionMethod(...explode('@', $route->getAction('uses')));

roave/better-reflection:

return new ReflectionMethod($this->betterReflectionObject->getConstructor());

Detection in PHP 8.2

• ReflectionMethod::createFromMethodName is invalid.
• Any form of new ReflectionMethod(...) is unchanged and out of scope for this version, see "Syntax Variations" below.

Detection in PHP 8.3

• ReflectionMethod::createFromMethodName is valid.
• Any form of new ReflectionMethod(...) is unchanged and out of scope for this version, see "Syntax Variations" below.

Detection in PHP 8.4

• new ReflectionMethod(...) with 1 argument is deprecated, add warning. See "Syntax Variations" below.

Syntax Variations

• ReflectionMethod::createFromMethodName ✅ Can be handled by PHPCompatibility.
• new ReflectionMethod(...) ✅ Can be handled by PHPCompatibility.
• $className = 'ReflectionMethod'; new $className(); ❌ Unreliable, as $className could be defined anywhere.
• new SomeClassWhichExtendsReflectionMethod(...) ❌ Can't be handled.
• class Foo extends ReflectionMethod { ... parent::__construct(...) ... } ✅ Should be doable.

3v4l.org

• ReflectionMethod::createFromMethodName - named constructor forbidden in PHP <=8.2
• ReflectionMethod::__construct - signature 2 deprecated in PHP >=8.4
• Child of ReflectionMethod - parent::__construct - check 1st level of inheritance, 2nd level is out of scope

References

• RFC: Deprecate functions with overloaded signatures
• PR: Implement overloaded function deprecations for PHP 8.4 - part 1
  • Commit: Deprecate calling ReflectionMethod::__construct() with 1 argument
• PR: Implement "Deprecate functions with overloaded signatures" RFC for PHP 8.3
  • Commit: Implement ReflectionMethod::createFromMethodName()
• PHP 8.3 Release
• Not mentioned in the PHP 8.4 Release
• PHP Manual:
  • Migrating from PHP 8.2.x to PHP 8.3.x - New Functions
  • Migrating from PHP 8.3.x to PHP 8.4.x - Deprecated Features
  • ReflectionMethod::__construct
  • ReflectionMethod::createFromMethodName