protected virtual DbGroupAggregate VisitGroupAggregate(DbGroupAggregate aggregate) { var result = aggregate; if (aggregate != null) { var newArguments = VisitExpressionList(aggregate.Arguments); Debug.Assert(newArguments.Count == 1, "Group aggregate had more than one argument?"); if (!ReferenceEquals(aggregate.Arguments, newArguments)) { result = CqtBuilder.GroupAggregate(newArguments[0]); } } return(result); }