When using disk encryption, swap is not encrypted

I am using version 3.19.1. When installing the system with

setup-disk -e -m sys /dev/sda
 # -e for encrypted
 # -m for system disk

The script creates an encrypted system partition and an unencrypted swap partition, mounted at boot.

Wouldn't a plain-text swap partition leak the key material, and other confidential information, when the system is running? At the very least, I think we can suggest -s 0 for no swap for this scenario and use a swap file instead.