Fix S2325 FP: "Make 'MethodName' a static method." should not apply to overriding instance methods

[richardissimo]

Description

S2325 Make 'MethodName' a static method. If I have an abstract class with a virtual method, and the derived class has an implementation which could be made static, this should not trigger this rule, because it is overriding the virtual.

Repro steps

    public abstract class DemoProblem
    {
        protected virtual bool IsAllowed()
        {
            return true;
        }
    }

    public class DerivedClass : DemoProblem
    {
        public bool IsAllowed() // Triggers S2325
        {
            return false;
        }
    }

Expected behavior

Should not trigger S2325

Actual behavior

triggers S2325

Known workarounds

Suppress rule

Related information

• SonarAnalyzer.CSharp 9.32.0.97167
• Visual Studio version 17.11.0
• MSBuild / dotnet version netstandard2.0;net452;net48;net6.0;net8.0
• Operating System Windows 10

[richardissimo]

Hmm. My made up example isn't exactly what I had for real, and I can see in that example, the DerivedClass implementation should override. I'll see if I can find a better example, closer to my problem.

[richardissimo]

No, I'm withdrawing this. This is more like what the actual code looks like, so fair enough, that can be made static.

    public abstract class Rule
    {
        protected string SimplifyWhitespaceExpression(string expression)
        {
            // Implementation isn't relevant, but it can be made static
        }