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    <h3>Editing: Reflection.php</h3>
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/**
 * This file is part of the Nette Framework (https://nette.org)
 * Copyright (c) 2004 David Grudl (https://davidgrudl.com)
 */

declare(strict_types=1);

namespace Nette\Utils;

use Nette;


/**
 * PHP reflection helpers.
 */
final class Reflection
{
	use Nette\StaticClass;

	/**
	 * Determines if type is PHP built-in type. Otherwise, it is the class name.
	 */
	public static function isBuiltinType(string $type): bool
	{
		return Validators::isBuiltinType($type);
	}


	/**
	 * Determines if type is special class name self/parent/static.
	 */
	public static function isClassKeyword(string $name): bool
	{
		return Validators::isClassKeyword($name);
	}


	/**
	 * Returns the type of return value of given function or method and normalizes `self`, `static`, and `parent` to actual class names.
	 * If the function does not have a return type, it returns null.
	 * If the function has union or intersection type, it throws Nette\InvalidStateException.
	 * @deprecated use Nette\Utils\Type::fromReflection()
	 */
	public static function getReturnType(\ReflectionFunctionAbstract $func): ?string
	{
		$type = $func-&gt;getReturnType() ?? (PHP_VERSION_ID &gt;= 80100 &amp;&amp; $func instanceof \ReflectionMethod ? $func-&gt;getTentativeReturnType() : null);
		return self::getType($func, $type);
	}


	/**
	 * @deprecated
	 */
	public static function getReturnTypes(\ReflectionFunctionAbstract $func): array
	{
		$type = Type::fromReflection($func);
		return $type ? $type-&gt;getNames() : [];
	}


	/**
	 * Returns the type of given parameter and normalizes `self` and `parent` to the actual class names.
	 * If the parameter does not have a type, it returns null.
	 * If the parameter has union or intersection type, it throws Nette\InvalidStateException.
	 * @deprecated use Nette\Utils\Type::fromReflection()
	 */
	public static function getParameterType(\ReflectionParameter $param): ?string
	{
		return self::getType($param, $param-&gt;getType());
	}


	/**
	 * @deprecated
	 */
	public static function getParameterTypes(\ReflectionParameter $param): array
	{
		$type = Type::fromReflection($param);
		return $type ? $type-&gt;getNames() : [];
	}


	/**
	 * Returns the type of given property and normalizes `self` and `parent` to the actual class names.
	 * If the property does not have a type, it returns null.
	 * If the property has union or intersection type, it throws Nette\InvalidStateException.
	 * @deprecated use Nette\Utils\Type::fromReflection()
	 */
	public static function getPropertyType(\ReflectionProperty $prop): ?string
	{
		return self::getType($prop, PHP_VERSION_ID &gt;= 70400 ? $prop-&gt;getType() : null);
	}


	/**
	 * @deprecated
	 */
	public static function getPropertyTypes(\ReflectionProperty $prop): array
	{
		$type = Type::fromReflection($prop);
		return $type ? $type-&gt;getNames() : [];
	}


	/**
	 * @param  \ReflectionFunction|\ReflectionMethod|\ReflectionParameter|\ReflectionProperty  $reflection
	 */
	private static function getType($reflection, ?\ReflectionType $type): ?string
	{
		if ($type === null) {
			return null;

		} elseif ($type instanceof \ReflectionNamedType) {
			return Type::resolve($type-&gt;getName(), $reflection);

		} elseif ($type instanceof \ReflectionUnionType || $type instanceof \ReflectionIntersectionType) {
			throw new Nette\InvalidStateException('The ' . self::toString($reflection) . ' is not expected to have a union or intersection type.');

		} else {
			throw new Nette\InvalidStateException('Unexpected type of ' . self::toString($reflection));
		}
	}


	/**
	 * Returns the default value of parameter. If it is a constant, it returns its value.
	 * @return mixed
	 * @throws \ReflectionException  If the parameter does not have a default value or the constant cannot be resolved
	 */
	public static function getParameterDefaultValue(\ReflectionParameter $param)
	{
		if ($param-&gt;isDefaultValueConstant()) {
			$const = $orig = $param-&gt;getDefaultValueConstantName();
			$pair = explode('::', $const);
			if (isset($pair[1])) {
				$pair[0] = Type::resolve($pair[0], $param);
				try {
					$rcc = new \ReflectionClassConstant($pair[0], $pair[1]);
				} catch (\ReflectionException $e) {
					$name = self::toString($param);
					throw new \ReflectionException(&quot;Unable to resolve constant $orig used as default value of $name.&quot;, 0, $e);
				}

				return $rcc-&gt;getValue();

			} elseif (!defined($const)) {
				$const = substr((string) strrchr($const, '\\'), 1);
				if (!defined($const)) {
					$name = self::toString($param);
					throw new \ReflectionException(&quot;Unable to resolve constant $orig used as default value of $name.&quot;);
				}
			}

			return constant($const);
		}

		return $param-&gt;getDefaultValue();
	}


	/**
	 * Returns a reflection of a class or trait that contains a declaration of given property. Property can also be declared in the trait.
	 */
	public static function getPropertyDeclaringClass(\ReflectionProperty $prop): \ReflectionClass
	{
		foreach ($prop-&gt;getDeclaringClass()-&gt;getTraits() as $trait) {
			if ($trait-&gt;hasProperty($prop-&gt;name)
				// doc-comment guessing as workaround for insufficient PHP reflection
				&amp;&amp; $trait-&gt;getProperty($prop-&gt;name)-&gt;getDocComment() === $prop-&gt;getDocComment()
			) {
				return self::getPropertyDeclaringClass($trait-&gt;getProperty($prop-&gt;name));
			}
		}

		return $prop-&gt;getDeclaringClass();
	}


	/**
	 * 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.
	 */
	public static function getMethodDeclaringMethod(\ReflectionMethod $method): \ReflectionMethod
	{
		// file &amp; line guessing as workaround for insufficient PHP reflection
		$decl = $method-&gt;getDeclaringClass();
		if ($decl-&gt;getFileName() === $method-&gt;getFileName()
			&amp;&amp; $decl-&gt;getStartLine() &lt;= $method-&gt;getStartLine()
			&amp;&amp; $decl-&gt;getEndLine() &gt;= $method-&gt;getEndLine()
		) {
			return $method;
		}

		$hash = [$method-&gt;getFileName(), $method-&gt;getStartLine(), $method-&gt;getEndLine()];
		if (($alias = $decl-&gt;getTraitAliases()[$method-&gt;name] ?? null)
			&amp;&amp; ($m = new \ReflectionMethod($alias))
			&amp;&amp; $hash === [$m-&gt;getFileName(), $m-&gt;getStartLine(), $m-&gt;getEndLine()]
		) {
			return self::getMethodDeclaringMethod($m);
		}

		foreach ($decl-&gt;getTraits() as $trait) {
			if ($trait-&gt;hasMethod($method-&gt;name)
				&amp;&amp; ($m = $trait-&gt;getMethod($method-&gt;name))
				&amp;&amp; $hash === [$m-&gt;getFileName(), $m-&gt;getStartLine(), $m-&gt;getEndLine()]
			) {
				return self::getMethodDeclaringMethod($m);
			}
		}

		return $method;
	}


	/**
	 * Finds out if reflection has access to PHPdoc comments. Comments may not be available due to the opcode cache.
	 */
	public static function areCommentsAvailable(): bool
	{
		static $res;
		return $res ?? $res = (bool) (new \ReflectionMethod(__METHOD__))-&gt;getDocComment();
	}


	public static function toString(\Reflector $ref): string
	{
		if ($ref instanceof \ReflectionClass) {
			return $ref-&gt;name;
		} elseif ($ref instanceof \ReflectionMethod) {
			return $ref-&gt;getDeclaringClass()-&gt;name . '::' . $ref-&gt;name . '()';
		} elseif ($ref instanceof \ReflectionFunction) {
			return $ref-&gt;name . '()';
		} elseif ($ref instanceof \ReflectionProperty) {
			return self::getPropertyDeclaringClass($ref)-&gt;name . '::$' . $ref-&gt;name;
		} elseif ($ref instanceof \ReflectionParameter) {
			return '$' . $ref-&gt;name . ' in ' . self::toString($ref-&gt;getDeclaringFunction());
		} else {
			throw new Nette\InvalidArgumentException;
		}
	}


	/**
	 * Expands the name of the class to full name in the given context of given class.
	 * Thus, it returns how the PHP parser would understand $name if it were written in the body of the class $context.
	 * @throws Nette\InvalidArgumentException
	 */
	public static function expandClassName(string $name, \ReflectionClass $context): string
	{
		$lower = strtolower($name);
		if (empty($name)) {
			throw new Nette\InvalidArgumentException('Class name must not be empty.');

		} elseif (Validators::isBuiltinType($lower)) {
			return $lower;

		} elseif ($lower === 'self' || $lower === 'static') {
			return $context-&gt;name;

		} elseif ($lower === 'parent') {
			return $context-&gt;getParentClass()
				? $context-&gt;getParentClass()-&gt;name
				: 'parent';

		} elseif ($name[0] === '\\') { // fully qualified name
			return ltrim($name, '\\');
		}

		$uses = self::getUseStatements($context);
		$parts = explode('\\', $name, 2);
		if (isset($uses[$parts[0]])) {
			$parts[0] = $uses[$parts[0]];
			return implode('\\', $parts);

		} elseif ($context-&gt;inNamespace()) {
			return $context-&gt;getNamespaceName() . '\\' . $name;

		} else {
			return $name;
		}
	}


	/** @return array&lt;string, class-string&gt; of [alias =&gt; class] */
	public static function getUseStatements(\ReflectionClass $class): array
	{
		if ($class-&gt;isAnonymous()) {
			throw new Nette\NotImplementedException('Anonymous classes are not supported.');
		}

		static $cache = [];
		if (!isset($cache[$name = $class-&gt;name])) {
			if ($class-&gt;isInternal()) {
				$cache[$name] = [];
			} else {
				$code = file_get_contents($class-&gt;getFileName());
				$cache = self::parseUseStatements($code, $name) + $cache;
			}
		}

		return $cache[$name];
	}


	/**
	 * Parses PHP code to [class =&gt; [alias =&gt; class, ...]]
	 */
	private static function parseUseStatements(string $code, ?string $forClass = null): array
	{
		try {
			$tokens = token_get_all($code, TOKEN_PARSE);
		} catch (\ParseError $e) {
			trigger_error($e-&gt;getMessage(), E_USER_NOTICE);
			$tokens = [];
		}

		$namespace = $class = null;
		$classLevel = $level = 0;
		$res = $uses = [];

		$nameTokens = PHP_VERSION_ID &lt; 80000
			? [T_STRING, T_NS_SEPARATOR]
			: [T_STRING, T_NS_SEPARATOR, T_NAME_QUALIFIED, T_NAME_FULLY_QUALIFIED];

		while ($token = current($tokens)) {
			next($tokens);
			switch (is_array($token) ? $token[0] : $token) {
				case T_NAMESPACE:
					$namespace = ltrim(self::fetch($tokens, $nameTokens) . '\\', '\\');
					$uses = [];
					break;

				case T_CLASS:
				case T_INTERFACE:
				case T_TRAIT:
				case PHP_VERSION_ID &lt; 80100
					? T_CLASS
					: T_ENUM:
					if ($name = self::fetch($tokens, T_STRING)) {
						$class = $namespace . $name;
						$classLevel = $level + 1;
						$res[$class] = $uses;
						if ($class === $forClass) {
							return $res;
						}
					}

					break;

				case T_USE:
					while (!$class &amp;&amp; ($name = self::fetch($tokens, $nameTokens))) {
						$name = ltrim($name, '\\');
						if (self::fetch($tokens, '{')) {
							while ($suffix = self::fetch($tokens, $nameTokens)) {
								if (self::fetch($tokens, T_AS)) {
									$uses[self::fetch($tokens, T_STRING)] = $name . $suffix;
								} else {
									$tmp = explode('\\', $suffix);
									$uses[end($tmp)] = $name . $suffix;
								}

								if (!self::fetch($tokens, ',')) {
									break;
								}
							}
						} elseif (self::fetch($tokens, T_AS)) {
							$uses[self::fetch($tokens, T_STRING)] = $name;

						} else {
							$tmp = explode('\\', $name);
							$uses[end($tmp)] = $name;
						}

						if (!self::fetch($tokens, ',')) {
							break;
						}
					}

					break;

				case T_CURLY_OPEN:
				case T_DOLLAR_OPEN_CURLY_BRACES:
				case '{':
					$level++;
					break;

				case '}':
					if ($level === $classLevel) {
						$class = $classLevel = 0;
					}

					$level--;
			}
		}

		return $res;
	}


	private static function fetch(array &amp;$tokens, $take): ?string
	{
		$res = null;
		while ($token = current($tokens)) {
			[$token, $s] = is_array($token) ? $token : [$token, $token];
			if (in_array($token, (array) $take, true)) {
				$res .= $s;
			} elseif (!in_array($token, [T_DOC_COMMENT, T_WHITESPACE, T_COMMENT], true)) {
				break;
			}

			next($tokens);
		}

		return $res;
	}
}
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