I thought about this, but just testing "which node" could return 0 if node was in /usr/bin, or any other directory in $PATH.  What if I inadvertently ran two nodejs cookbooks?  We just made the switch from the "node" cookbook to this one.

Testing that the result of "which node" is "/usr/local/bin/node" guarantees that the system's path contains /usr/local/bin.

Serverspec might be a better choice but this is my first go-round with test-kitchen and everything else is written in BATS, so....