bug#22167: Invalid token errors with resizepart

Hi,

I'm trying to create a single command to increase a single root 
partition to the maximum size. Doing it step by step, I managed to do it 
interactively with:
> (parted) resizepart 1
> Warning: Partition /dev/vda1 is being used. Are you sure you want to continue?
> Yes/No? yes
> End?  [4000MB]? -1s

When I do it all on a single line, I get an error that -1s is an invalid 
token however:
> (parted) resizepart 1 -1s
> Warning: Partition /dev/vda1 is being used. Are you sure you want to continue?
> parted: invalid token: -1s

I tried other values as well, but it seems the end argument can't be 
parsed properly when it's specified with the initial call or I'm doing 
something wrong. Is there any way to get this to work?

I'm using GNU Parted 3.2 as shipped with Fedora 22.

Thanks in advance!

Best regards,
Julius