puppetlabs/puppet — pull request #2534 by hlindberg (2014-04-14 13:51:55+00:00)
Title: (PUP-2190) Fix issue when there are no defaults (for meta params)

When looking up a metaparameter - Notify['foo'][tag], this failed
when no tags had been set. The same problem would occur for any
parameter that the resource api reported to be a vaid parameter but
for which asking for its default did not return a Parameter.