groovy/groovy-core — pull request #18 by jwagenleitner (2012-01-19 19:52:23+00:00)
Title: GROOVY-5224: groovy.util.Node plus operator assuming all children are not strings

This fixes the issue reported. Even though the List returned from children() may contain mixed content of types Node and String, typing the local `List/ArrayList` wasn't causing any issues so I left as is. But can understand if a different approach is taken. Hopefully at least the tests may be of use.