mockDataService throws NoSuchMethodError

[zyro23]

trying to write a ServiceUnitTest and mock a data service that the service under test is using, i get a NoSuchMethodError:

java.lang.NoSuchMethodError: org.grails.datastore.mapping.core.AbstractDatastore.getService(Ljava/lang/Class;)Lorg/grails/datastore/mapping/services/Service;
	at grails.testing.gorm.DataTest$Trait$Helper.mockDataService(DataTest.groovy:96)
	at myapp.DummyServiceSpec.setupSpec(DummyServiceSpec.groovy:11)

but looking at the code (i.e. the AbstractDatastore.getService method signature), i cannot figure out whats wrong.

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