public static List<? extends Token> tokenize(String format)
    {
        DateFormat lexer = new com.facebook.presto.teradata.functions.DateFormat(new ANTLRInputStream(format));
        return lexer.getAllTokens();
    }
@Test
    public void testGreedinessLongFirst()
    {
        assertEquals(1, DateFormatParser.tokenize("yy").size());
        assertEquals(1, DateFormatParser.tokenize("yyyy").size());
        assertEquals(2, DateFormatParser.tokenize("yyyyyy").size());
    }