ScriptDom.TSql160Parser fails to parse simple T-SQL expression

[Clement Gutel]

• Microsoft.SqlServer.DacFx Version 161.6374.0
• Reproduced on both .NET 6.0 and .NET 7.0
• Windows 11

The Microsoft.SqlServer.TransactSql.ScriptDom.TSql160Parser fails to parse the following expression.

We noticed the issue on a much more complicated and realistic expression but we simplified the repro to the following minimal expression.

Repro:

using Microsoft.SqlServer.TransactSql.ScriptDom;

var parser = new TSql160Parser(true); //sql server 2022 parser
IList<ParseError> errors;

var expr = @"
(
    SELECT 1
    WHERE (IIF(1 > 0 AND 2 > 1, 1, 0)) = 1
)";

var res = parser.ParseExpression(new StringReader(expr), out errors);

if (errors?.Count > 0)
    Console.WriteLine(errors.First().Message); //ERROR!!!!    Incorrect syntax near ).

To prove that the given expression is definitely a valid one, you can simply execute the following statement in SSMS and see that SQL SERVER executes the query succesfully.

SELECT
(
    SELECT 1
    WHERE (IIF(1 > 0 AND 2 > 1, 1, 0)) = 1
)

[Clement Gutel]

@llali Could this be addressed with the release of the sql server 2022 parser?

[SeenaAugusty]

Hi @clement911, this expression worked
var expr = @"
(
SELECT 1
WHERE IIF(1 > 0 AND 2 > 1, 1, 0) = 1
)";

[Clement Gutel]

That's right. The parser gets confused by extra wrapping parentheses so hopefully the code fix is not too hard?

Of course we wouldn't write such a simple expression manually but our actual expression is much more complicated. Also, sql is sometimes autogenerated or provided by a user, in which case we have no control over it.

[Clement Gutel]

Could we please get an update on this bug?

[SeenaAugusty]

@clement911 Apologies for the delay, would update you whether it would be included in the next release. Thank you

[Clement Gutel]

@SeenaAugusty we really look forward to it.

By the way, if you would open source the parser, we'd be happy to spend some time working on such issues

[SeenaAugusty]

@clement911 we are planning to make it open source in near future :)

[Clement Gutel]

@SeenaAugusty this is great news that you will open source this project 😄

However, I was also told the same thing.... 2.5 years ago.

Could you share the (rough) time line of when you will be open sourcing this project?

[Clement Gutel]

Hi, any updates on this issue?

[Clement Gutel]

@SeenaAugusty any news on the open sourcing?
Bugs remain open for months or years so the only hope I see of them getting fixed is if you open source the code.

[Drew Skwiers-Koballa]

While the time it takes to bring ScriptDOM to open source may be frustrating, we'll keep those conversations primarily over at microsoft/DacFx#101

[Clement Gutel]

@dzsquared could you give a quick update there?
Are you still working towards open sourcing the ScriptDom?

[Clement Gutel]

Thank you to the team for open sourcing this wonderful library 😍

[Clement Gutel]

Any chance this bug could get looked at ?

[Chris LaFreniere]

@SeenaAugusty are you looking into this currently? If not, I can take a crack at this 😄

[SeenaAugusty]

@chlafreniere sure, not yet though,