ApplicationServiceRegistry
.identityApplicationService()
.addUserToGroup(new AddUserToGroupCommand(
childGroup.tenantId().id(),
childGroup.name(),
user.username()));
assertEquals(1, parentGroup.groupMembers().size());
assertEquals(1, childGroup.groupMembers().size());
assertTrue(parentGroup.isMember(user, DomainRegistry.groupMemberService()));
assertTrue(childGroup.isMember(user, DomainRegistry.groupMemberService()));