@Test
public void testAtLiteralDuration() {

    String inputExpression = "@\"P2Y2M\"";
    BaseNode bool = parse(inputExpression);
    assertThat(bool, is(instanceOf(AtLiteralNode.class)));
    assertThat(bool.getResultType(), is(BuiltInType.DURATION));
    assertLocation(inputExpression, bool);
}