Example of a non-trivial TDD grails project with an educational/informative commit history
I have made some pretty cool things with grails, but I am still unable to wrap my head around testing.  Is there a public project with a commit history that I can follow which shows good TDD practice?  Ideally some failing tests get committed and then some passing code gets committed, rinse and repeat.

Fantasy preferences:  using git, testing done with spock or easyb or cucumber, has some interesting/hard-to-test plugins like the mail plugin or rabbitMQ.
Example of a non-trivial TDD grails project with an educational/informative commit history
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I have made some pretty cool things with grails, but I am still unable to wrap my head around testing.  Is there a public project with a commit history that I can follow which shows good TDD practice?  Ideally some failing tests get committed and then some passing code gets committed, rinse and repeat.

Fantasy preferences:  using git, testing done with spock or easyb or cucumber, has some interesting/hard-to-test plugins like the mail plugin or rabbitMQ.