These are test manifests used by a member of the Puppet Labs documentation crew. Because they explore a lot of edge cases and oddities in the language, they're filled with some pretty terrible ideas. But they might be useful for other people doing the same thing, and maybe I'll get pull requests with interesting test code I haven't thought of yet.
See the comments in each file for info about what it's demonstrating. Unless I was being lazy and didn't put comments in.