Aerys\Root::lookup PHP Method

    private function lookup(string $path) : \Generator
    {
        $fileInfo = new class
        {
            use amp\Struct;
            public $exists;
            public $path;
            public $size;
            public $mtime;
            public $inode;
            public $buffer;
            public $etag;
            public $handle;
        };
        $fileInfo->exists = false;
        $fileInfo->path = $path;
        if (!($stat = (yield $this->filesystem->stat($path)))) {
            return $fileInfo;
        }
        if ((yield $this->filesystem->isdir($path))) {
            if ($indexPathArr = (yield from $this->coalesceIndexPath($path))) {
                list($fileInfo->path, $stat) = $indexPathArr;
            } else {
                return $fileInfo;
            }
        }
        $fileInfo->exists = true;
        $fileInfo->size = (int) $stat["size"];
        $fileInfo->mtime = $stat["mtime"] ?? 0;
        $fileInfo->inode = $stat["ino"] ?? 0;
        $inode = $this->useEtagInode ? $fileInfo->inode : "";
        $fileInfo->etag = \md5("{$fileInfo->path}{$fileInfo->mtime}{$fileInfo->size}{$inode}");
        if ($this->shouldBufferContent($fileInfo)) {
            $fileInfo->buffer = (yield $this->filesystem->get($fileInfo->path));
            $this->bufferedFileCount++;
        }
        return $fileInfo;
    }