Deploying environments fails with recent r10k versions

[mattock]

Latest r10k does not seem to work properly in our context:

root@puppet:~# r10k deploy environment production -vp -c /etc/puppetlabs/r10k/r10k.yaml

r10k: Runtime error: #<NoMethodError: undefined method `[]=' for nil:NilClass> 

This is with r10k version 3.2.0. I suspect that the new version cannot parse the old-format config file, r10k.yaml, and hence fails with this very unhelpful error message.

The workaround is to downgrade to r10k 2.6.5:

/opt/puppetlabs/puppet/bin/gem uninstall r10k
/opt/puppetlabs/puppet/bin/gem install r10k -v 2.6.5