Set a hasMany collection on a domain object using BuildTestsData

gistfile1.txt

class Foo {
   Bar bar
}

class Bar {
   static belongsTo = Foo
   static hasMany = [bazzes: Baz]
}

class Baz {
   static belongsTo = [bar: Bar]
}

TestDataConfig.groovy
'Foo' {
   bar = {
      def b = Bar.buildWithoutSave()
      3.times {
         b.addToBazzes(new Baz())
      }
      b
   }
}