Recursive Glob implementation

recursive-glob.php

function glob_recursive(string $dir, string $pattern, int $flags = GLOB_BRACE): Iterator
{
    $path = realpath($dir);
    if ($path === false) {
        throw new RuntimeException("Invalid dir: {$dir}");
    }

    $glob = function (string $path) use ($pattern, $flags, &$glob) {
        yield from glob("{$path}/{$pattern}", $flags);
        foreach (new DirectoryIterator($path) as $file) {
            if ($file->isDir() && !$file->isDot()) {
                yield from $glob($file->getPathname());
            }
        }
    };

    $cwd = getcwd();
    chdir($path);
    yield from $glob($path);
    chdir($cwd);
}