A Null Object is a drop in replacement for one of the other objects in your
system that provides sensible defaults when the other object is unavailable.
For example, I recently wrote about
returning the path to a blank partial as a sensible default for
Null Objects remove
and make code cleaner and easier to understand. It almost seems like there's
no downside. Almost.
Read this post in full on the thoughtbot blog: https://robots.thoughtbot.com/testing-null-objects