Foreman-installer not working with future parser

Hi,

I've been trying out Foreman using foreman-installer, and have found that
it fails to run if any of these features are present in
/etc/puppet/puppet.conf :

parser=future
strict_variables=true
trusted_node_data=true

It doesn't need them all; any one of them is enough to cause this error
with no further detail in the log:

[root@f ~]# foreman-installer --help
Could not get default values, check log file at
/var/log/foreman-installer/foreman-installer.log for more information

Anybody else seen this, or know if it's a known problem? I've reproduced it
on a blank CentOS 7 VM, following the quickstart to install
foreman-installer from repositories, then adding one of the lines to
puppet.conf.

I know they're experimental Puppet features and I think I could work around
it by disabling them for running the installer then changing them back, but
Puppet 4 is dropping imminently and these features will start to become
defaults so hopefully they'll be supported soon. Or at least kafo could use
an internal conf file and ignore external puppet settings.