WIP add a test demonstrating issue

See grails#195

Note: test is not currently functional: failing to instantiate data
service for test.

grails-datastore-gorm-mongodb/src/test/groovy/org/grails/datastore/gorm/mongo/EmbeddedWhereClauseSpec.groovy

@@ -0,0 +1,57 @@
+package org.grails.datastore.gorm.mongo
+
+import grails.gorm.services.Service
+import grails.gorm.services.Where
+import grails.gorm.tests.GormDatastoreSpec
+import grails.persistence.Entity
+import org.springframework.beans.factory.annotation.Autowired
+
+import javax.persistence.Embeddable
+
+class EmbeddedWhereClauseSpec extends GormDatastoreSpec {
+
+    @Autowired
+    PersonAttributeDataService personAttributeDataService
+
+    void "Can construct data service where clause on embedded object"() {
+        given:"An object with an embedded field on it"
+        def attribute = new PersonAttribute(contexts: [new AttributeContext(neighborhoodId: '1234')])
+        attribute.save()
+
+        when:"We query using the autogenerated where clause"
+        def response = personAttributeDataService.findByNeighborhoodId('1234')
+
+        then:"The association is valid"
+        response.size() == 1
+        response.first().contexts.first().neighborhoodId == '1234'
+
+    }
+
+    @Override
+    List getDomainClasses() {
+        [PersonAttribute]
+    }
+}
+
+@Entity
+class PersonAttribute {
+    String id
+    List<AttributeContext> contexts = []
+    static embedded = ['contexts']
+}
+
+@Embeddable
+class AttributeContext {
+
+    String id
+    String neighborhoodId
+
+    static belongsTo = [attribute: PersonAttribute]
+
+}
+
+@Service(PersonAttribute)
+interface PersonAttributeDataService {
+    @Where({ contexts { neighborhoodId == neighborhoodId } })
+    List<PersonAttribute> findByNeighborhoodId(String neighborhoodId)
+}