findChildFiles: Distinguish between failure and empty folder

If File::findChildFiles() runs into an error accessing the folder, it returns an empty Array instead of indicating an error. In my case, isDirectory() returns true, but findChildFiles() returns an empty Array though there are files in the folder. This can happen on iOS, if there’s a problem with security-scoped URL access.

Is there a way to distinguish between “error accessing the folder” and “success, but the folder is empty”? I need this to show the correct message to the user. For example if the access failed, I don’t want to show “the folder is empty”.

This also affects File::copyDirectoryTo(): If findChildFiles() fails, copyDirectoryTo returns true though nothing was copied.