PHP Reflection

Nette\Utils\Reflection is a static class with useful functions for PHP reflection. Its purpose is to fix flaws in native classes and to unify behavior across different versions of PHP.

Installation:

composer require nette/utils

All examples assume the following class alias is defined:

use Nette\Utils\Reflection;

areCommentsAvailable(): bool

Finds out if reflection has access to PHPdoc comments. Comments may not be available due to the opcode cache, see for example the directive opcache.save-comments.

expandClassName (string $name, ReflectionClass $context): string

Expands the $name of the class to full name in the context of the $context, ie in the context of its namespace and defined aliases. Thus, it returns how the PHP parser would understand $name if it were written in the body of the $context.

namespace Foo;
use Bar;

class DemoClass
{
	// new Bar, new Baz
}

$context = new ReflectionClass(Foo\DemoClass::class);
Reflection::expandClassName('Bar', $context); // 'Bar'
Reflection::expandClassName('Baz', $context); // 'Foo\Baz'

getMethodDeclaringMethod (ReflectionMethod $method): ReflectionMethod

Returns a reflection of a method that contains a declaration of $method. Usually, each method is its own declaration, but the body of the method can also be in the trait and under a different name.

Because PHP does not provide enough information to determine the actual declaration, Nette uses its own heuristics, which should be reliable.

trait DemoTrait
{
	function foo()
	{
	}
}


class DemoClass
{
	use DemoTrait {
		DemoTrait::foo as foo2;
	}
}


$method = new ReflectionMethod('DemoClass::foo2');
Reflection::getMethodDeclaringMethod($method); // ReflectionMethod('DemoTrait::foo')

getParameterDefaultValue (ReflectionParameter $param)

Returns the default value of $param in a function or method. If it is a constant, it returns its value. If the parameter does not have a default value or the constant cannot be resolved, it throws ReflectionException.

class DemoClass
{
	function foo($param = PDO::FETCH_BOTH)
	{
	}
}

$method = new ReflectionMethod('DemoClass::foo');
Reflection::getParameterDefaultValue($method->getParameters()[0]);

getParameterType (ReflectionParameter $param): ?string

Returns the type of the function or method $param parameter and resolves self and parent to the actual class name. If the parameter has no type, it returns null, if it has a union or intersection type it throws Nette\InvalidStateException.

class DemoClass
{
	function foo(self $param)
	{
	}
}

$method = new ReflectionMethod('DemoClass::foo');
Reflection::getParameterType($method->getParameters()[0]); // 'DemoClass'

This method was created when PHP did not have union and intersection types. It is replaced by the method Nette\Utils\Type::fromReflection().

getPropertyDeclaringClass (ReflectionProperty $prop): ReflectionClass

Returns a reflection of a class or trait that contains a declaration of property $prop. Property can also be declared in the trait.

Because PHP does not provide enough information to determine the actual declaration, Nette uses its own heuristics, which are not reliable.

trait DemoTrait
{
	public $foo;
}


class DemoClass
{
	use DemoTrait;
}

$prop = new ReflectionProperty(DemoClass::class, 'foo');
Reflection::getPropertyDeclaringClass($prop); // ReflectionClass('DemoTrait')

getPropertyType (ReflectionProperty $prop): ?string

Returns the type of property $prop and resolves self and parent to the actual class name. If property has no type, it returns null, if it has a union or intersection type it throws Nette\InvalidStateException.

class DemoClass
{
	public self $foo;
}

$prop = new ReflectionProperty(DemoClass::class, 'foo');
Reflection::getPropertyType($prop); // 'DemoClass'

This method was created when PHP did not have union and intersection types. It is replaced by the method Nette\Utils\Type::fromReflection().

getReturnType (ReflectionFunctionAbstract $func): ?string

Returns the return type of the function or method $func and resolves self, static and parent to the actual class name. If the function does not have a return type, it returns null, if it has a union or intersection type it throws Nette\InvalidStateException.

class DemoClass
{
	function foo(): self
	{
	}
}

$method = new ReflectionMethod('DemoClass::foo');
Reflection::getReturnType($method); // 'DemoClass'

This method was created when PHP did not have union and intersection types. It is replaced by the method Nette\Utils\Type::fromReflection().

isBuiltinType (string $type): bool

Determines if $type is PHP built-in type. Otherwise, it is the class name.

Reflection::isBuiltinType('string'); // true
Reflection::isBuiltinType('Foo');    // false

toString ($reflection): string

Converts a reflection to a human readable string.

$func = new ReflectionFunction('func');
echo Reflection::toString($func); // 'func' ('func()' since v3.2.0)

$class = new ReflectionClass('DemoClass');
echo Reflection::toString($class); // 'DemoClass'

$method = new ReflectionMethod('DemoClass', 'foo');
echo Reflection::toString($method); // 'DemoClass::foo' ('DemoClass::foo()' since v3.2.0)

$param = new ReflectionParameter(['DemoClass', 'foo'], 'param');
echo Reflection::toString($param); // '$param in DemoClass::foo()'

$prop = new ReflectionProperty('DemoClass', 'foo');
echo Reflection::toString($prop); // 'DemoClass::$foo'