Test case for #676 (GRAILS-11855). The fix is in grails-data-mapping.

grails-test-suite-persistence/src/test/groovy/grails/test/mixin/domain/SaveDomainSpec.groovy

@@ -0,0 +1,36 @@
+package grails.test.mixin.domain
+
+import grails.persistence.Entity
+import grails.test.mixin.TestFor
+import spock.lang.Specification
+
+@TestFor(Person)
+class SaveDomainSpec extends Specification {
+
+    void 'test dateCreated and lastUpdated populated'() {
+        given:
+        Person person = new Person(name: 'Bobby')
+
+        when:
+        person.save(flush: true)
+
+        then:
+        person.dateCreated != null
+        person.lastUpdated != null
+        person.dateCreated == person.lastUpdated
+
+        when:
+        person.name = 'Bobby Updated'
+        person.save(flush: true)
+
+        then:
+        person.lastUpdated > person.dateCreated
+    }
+}
+
+@Entity
+class Person {
+    String name
+    Date dateCreated
+    Date lastUpdated
+}