<?php
/*
* This file is part of the Symfony package.
*
* (c) Fabien Potencier <fabien@symfony.com>
*
* For the full copyright and license information, please view the LICENSE
* file that was distributed with this source code.
*/
namespace Symfony\Component\String;
/**
* A string whose value is computed lazily by a callback.
*
* @author Nicolas Grekas <p@tchwork.com>
*/
class LazyString implements \Stringable, \JsonSerializable
{
private $value;
/**
* @param callable|array $callback A callable or a [Closure, method] lazy-callable
*
* @return static
*/
public static function fromCallable($callback, ...$arguments): self
{
if (!\is_callable($callback) && !(\is_array($callback) && isset($callback[0]) && $callback[0] instanceof \Closure && 2 >= \count($callback))) {
throw new \TypeError(sprintf('Argument 1 passed to "%s()" must be a callable or a [Closure, method] lazy-callable, "%s" given.', __METHOD__, get_debug_type($callback)));
}
$lazyString = new static();
$lazyString->value = static function () use (&$callback, &$arguments, &$value): string {
if (null !== $arguments) {
if (!\is_callable($callback)) {
$callback[0] = $callback[0]();
$callback[1] = $callback[1] ?? '__invoke';
}
$value = $callback(...$arguments);
$callback = self::getPrettyName($callback);
$arguments = null;
}
return $value ?? '';
};
return $lazyString;
}
/**
* @param string|int|float|bool|\Stringable $value
*
* @return static
*/
public static function fromStringable($value): self
{
if (!self::isStringable($value)) {
throw new \TypeError(sprintf('Argument 1 passed to "%s()" must be a scalar or a stringable object, "%s" given.', __METHOD__, get_debug_type($value)));
}
if (\is_object($value)) {
return static::fromCallable([$value, '__toString']);
}
$lazyString = new static();
$lazyString->value = (string) $value;
return $lazyString;
}
/**
* Tells whether the provided value can be cast to string.
*/
final public static function isStringable($value): bool
{
return \is_string($value) || $value instanceof self || (\is_object($value) ? method_exists($value, '__toString') : is_scalar($value));
}
/**
* Casts scalars and stringable objects to strings.
*
* @param object|string|int|float|bool $value
*
* @throws \TypeError When the provided value is not stringable
*/
final public static function resolve($value): string
{
return $value;
}
/**
* @return string
*/
public function __toString()
{
if (\is_string($this->value)) {
return $this->value;
}
try {
return $this->value = ($this->value)();
} catch (\Throwable $e) {
if (\TypeError::class === \get_class($e) && __FILE__ === $e->getFile()) {
$type = explode(', ', $e->getMessage());
$type = substr(array_pop($type), 0, -\strlen(' returned'));
$r = new \ReflectionFunction($this->value);
$callback = $r->getStaticVariables()['callback'];
$e = new \TypeError(sprintf('Return value of %s() passed to %s::fromCallable() must be of the type string, %s returned.', $callback, static::class, $type));
}
if (\PHP_VERSION_ID < 70400) {
// leverage the ErrorHandler component with graceful fallback when it's not available
return trigger_error($e, \E_USER_ERROR);
}
throw $e;
}
}
public function __sleep(): array
{
$this->__toString();
return ['value'];
}
public function jsonSerialize(): string
{
return $this->__toString();
}
private function __construct()
{
}
private static function getPrettyName(callable $callback): string
{
if (\is_string($callback)) {
return $callback;
}
if (\is_array($callback)) {
$class = \is_object($callback[0]) ? get_debug_type($callback[0]) : $callback[0];
$method = $callback[1];
} elseif ($callback instanceof \Closure) {
$r = new \ReflectionFunction($callback);
if (false !== strpos($r->name, '{closure}') || !$class = $r->getClosureScopeClass()) {
return $r->name;
}
$class = $class->name;
$method = $r->name;
} else {
$class = get_debug_type($callback);
$method = '__invoke';
}
return $class.'::'.$method;
}
}