Grails Command Object Integration test failure

Exception

No signature of method: com.example.FooCommandBean.validate() is applicable for argument types: () values: [] Possible solutions: wait()

groovy.lang.MissingMethodException: No signature of method: com.example.FooCommandBean.validate() is applicable for argument types: () values: []
Possible solutions: wait()
	at com.example.FooCommandBeanTests.testBar(FooCommandBeanTests.groovy:16)




https://github.com/ColinHarrington/Grails-Examples/blob/master/CommandIntegrationTest/test/integration/com/example/FooCommandBeanTests.groovy

https://github.com/ColinHarrington/Grails-Examples/blob/master/CommandIntegrationTest/grails-app/controllers/com/example/FooController.groovy