Fix S2589 FN: Tuple binary operations (comparison)

[zsolt-kolbay-sonarsource]

Description

S2589 doesn't work with binary tuple operations, resulting in FNs.

Repro steps

public class Repro_8486
{
    public void Method()
    {
        string text1 = SomeString();
        string text2 = SomeString();
        if ((text1, text2) == (null, null) && text1 != null)          // FN
        {
            Console.WriteLine();
        }
        if ((text1, text2) != (null, null) && text1 == null)          // FN
        {
            Console.WriteLine();
        }
        if ((text1, text2) != (SomeString(), null) && text1 == null)  // Compliant
        {
            Console.WriteLine();
        }

        string text3 = null;
        string text4 = "";
        string text5 = SomeString();
        if ((text3, text4) == (null, null))                      // FN
        {
            Console.WriteLine();
        }
        if ((text3, text4) != (null, null))                      // FN
        {
            Console.WriteLine();
        }
        if ((text3, text5) == (null, null))                      // Compliant
        {
            Console.WriteLine();
        }
    }

    private string SomeString() => "";
}

Expected behavior

S2589 should be raised.

Actual behavior

No issue is raised.

Implementation details

The rule itself doesn't need fixing. A Processor must be created for BinaryTupleOperation.

Related information

• C#/VB.NET Plugins version: 9.15
• Visual Studio version: 17.8.3
• Operating System: Windows 10