groovy/groovy-core — pull request #12 by jwagenleitner (2012-01-12 22:53:08+00:00)
Title: Fix for GROOVY-5247

Fixes issue introduced by GROOVY-5162 (commit c5456c808f0af5a) that causes a NPE when checking for null keys on certain Map implementations (i.e., TreeMap, Hashtable).