Possible false positive for ValidateArgumentsOfPublicMethods

Hot Topic

Detecting unused code across multiple assemblies
Logging files modifications
Correct steps to add users to team project
Import Fails if varchar/nvarchar set to MAX length
Problem with MSSCCI Provider
Version Control: How to Compare Directory vs Project?
gosh! why the heck???
Report server problem.
Support for WinForms Testing
Easy Question (Hopefully) - where is the process home page?!

VS Team System

Problems found when install TFS on a AD domain controller
"Object reference not set to an instance of an object"
Where is Beta 3 of the Team Foundation Server
Method fails in unit testing with System.Resources.MissingManifestResourceException
Team Foundation Report Errors after rebuild
Tailoring Code Analysis
Retrieving the Team Project name in MSProject
Build always checks out most of 'Bin' directory? (VS2005 Team Suite RC1)
Programmatic access to WebTest scripts
Problems running reports

Possible false positive for ValidateArgumentsOfPublicMethods

I added an == operator to a class.  Its method signature is

public static bool operator ==(Table table1, Table table2).

FxCop throws the ValidateArgumentsOfPublicMethods error and asks that I check the parameters for null.  OK, so I did.

if( table1 == null ||
    table2 == null )
{
  return false;
}

FxCop is now happy.  When I run my unit tests though, I get failures where the tests are throwing a StackOverflowException.  Upon further analysis, it appears that testing for null within the == operator introduces an infinite recursion situation.

What is the best way to handle this



Answer this question

Possible false positive for ValidateArgumentsOfPublicMethods

  • WalidDib

    This is definitely a good approach, just thought I'd point out that the BCL already provides such a useful static helper:

    if (Object.Equals(table1, null)) return false;

    etc

    Michael



  • RennySchweiger

    Since your == operator overloading on a reference type should have actually raised another violation; DoNotOverloadOperatorEqualsOnReferenceTypes, I don't think that FxCop should have given any other advice.



  • rpjimenez

    That is a great solution!

    Although it appears to solve my problem, should this situation be considered a false positive for ValidateArgumentsOfPublicMethods as it is currently implemented   

    If it flags this situation as a violation of the rule, should it not give advice similar to what you suggested above (only within the == operator method though)


  • mfroman

    I had the same problem and created a static method that checks for the null value. Because it takes an object, the == operator of the class is not used:



    private static bool IsNull(object table1)
    {
        return (null == table1);
    }

    public static bool operator ==(Table table1, Table table2)
    {
        if (IsNull(table1)) return false;
        if (IsNull(table2)) return false;
        ...
    }

     



  • Yin He

    So my situation is actually a false negative for the DoNotOverloadOperatorEqualsOnReferenceTypes rule Big Smile

    I sure like FxCop.  I learn alot about coding each time I use it.

    Thanks.
  • Possible false positive for ValidateArgumentsOfPublicMethods
Answer this question