Fix S3878 FP: Jagged arrays

[ThorstenReichert]

Description

When a C# method has an array of arrays as params parameter, S3878 is raised when the method is called. e.g. for

public class Repro8163
{
    public static void Method(params object[][] array) { }

    public static void CallParamsMethod()
    {
        Method(new[] { new object() }); // Noncompliant - FP
    }
}

Following the S3878 suggestion to "remove the array creation and simply pass the elements" will result in a compiler error (type mismatch "cannot convert from object to object[]").

Expected behavior

No issue is raised.

Actual behavior

S3878 is raised.

Known workarounds

Move the array creation to a separate variable, then pass that variable as method parameter.

Related information

• Visual Studio version: 17.6.1
• MSBuild / dotnet version: .NET 7
• SonarScanner for .NET version: Sonar Server Version 9.9.1 (build 69595) / SonarLint Version 7.3.0.77872
• Operating System: Windows 10

[zsolt-kolbay-sonarsource]

Thank you for reporting this issue. Confirmed as False Positive.

[martin-strecker-sonarsource]

Related #6894
Existing test case

sonar-dotnet/analyzers/tests/SonarAnalyzer.UnitTest/TestCases/ArrayPassedAsParams.cs

Line 98 in 7d09f45

MethodJuggedArray(new int[] { 1, 2 }); // Noncompliant, FP. Elements in args: [System.Object[]]