collectiveidea/awesome_nested_set — pull request #140 by tispratik (2012-05-15 19:12:20+00:00)
Title: Gracefully handle lft or rgt being nil when determining if the node is a leaf node

https://github.com/collectiveidea/awesome_nested_set/commit/01e70e07417059385e552b26189295b69117c390