ts.setNanos(123456);
ExprNodeConstantDesc constant = new ExprNodeConstantDesc(ts);
List<ExprNodeDesc> children = new ArrayList<ExprNodeDesc>(1);
children.add(constant);
ExprNodeGenericFuncDesc desc = new ExprNodeGenericFuncDesc(TypeInfoFactory.timestampTypeInfo,
new GenericUDFFromUtcTimestamp(), children);
assertEquals(desc.getExprString(), Utilities.deserializeExpression(
Utilities.serializeExpression(desc)).getExprString());
}