SonarCloud incorrectly flag an array as null in at least one case

p97 · January 6, 2022, 4:00pm

SonarCloud incorrectly flagged an array as null in at least one case.

Is this a known bug? Is there a work-around for this?

ALM used - Azure DevOps
CI - Azure DevOps
Languages of the repository - C#

costin.zaharia · January 11, 2022, 10:26am

Hi @p97,

I can confirm that this is a false positive, a known one. We have it documented here:

github.com

SonarSource/sonar-dotnet/blob/master/analyzers/tests/SonarAnalyzer.UnitTest/TestCases/SymbolicExecution/Sonar/NullPointerDereference.cs#L1031

    
      
                      };
          
          
            foreach (var providerCourse in providerCourses)
                      {
                          if (!providerCourse?.Items?.Any() ?? true)
                          {
                              Console.WriteLine("FAIL");
                              continue;
                          }
          
          
                var _ = providerCourse.Items.Where(items => items == "item1"); // Noncompliant FP
                      }
                  }
          
          
        class ProviderCourse
                  {
                      public IEnumerable<string> Items { get; set; }
                  }
              }
          }

As a workaround, you can replace the usage of the null-coalescence operator with a null equality check.

This is not great, I know, but we are working currently to improve our symbolic execution engine and reduce the number of false positives like this one.

Best,
Costin

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SonarCloud incorrectly flag an array as null in at least one case

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