file->move returns 1 not a file

ci 4.5.1. I'm using as per the docs,

PHP Code:

$file=$file->move('todir','newname',true);
   log_message('debug',$file->getSize());

   the file is moved correctly.
   according to the docs and line 153 of system/files/file.php, $file->move(...) returns a File [return new self($destination)]
   but $file->getSize() crashes  saying "Call to a member function getSize() on true" 


Many thanks, Bill

You are probably using UploadedFile, not File.
See https://github.com/codeigniter4/CodeIgni...#L130-L132

But UploadedFile extends File. So changing the return type is a violation of LSP.

ci-phpunit-test | CodeIgniter Testing Guide | CodeIgniter 3 to 4 Upgrade Helper

you're right (of course). I wasn't aware of Uploaded file. the source file is an upload and file->move(..) worked fine so i didn't search any further
thanks, Bill