src/Uri.php
private static function filterPath(?string $path): ?string
    {
        if ($path === null) {
            return null;
        }

        /** @link https://tools.ietf.org/html/rfc3986#section-3.3 */
        return preg_replace_callback(
            '/(?:[^a-zA-Z0-9_\-\.~:@&=\+\$,\/;%]+|%(?![A-Fa-f0-9]{2}))/',
            function ($match) {
                return rawurlencode($match[0]);
            },
            $path
        );
    }
private static function filterPath(?string $path): ?string
    {
        if ($path === null) {
            return null;
        }

        /** @link https://tools.ietf.org/html/rfc3986#section-3.3 */
        return preg_replace_callback(
            '/(?:[^a-zA-Z0-9_\-\.~:@&=\+\$,\/;%]+|%(?![A-Fa-f0-9]{2}))/',
            function ($match) {
                return rawurlencode($match[0]);
            },
            $path
        );
    }
Filters the URI path and percent-encodes reserved characters

@param string|null $path The path to filter if one is set, otherwise null
@return string|null The filtered path, or null if the path was already null