How to do it...

1. In Solution Explorer, double-click on the Resources.resx file in CSharpAnalyzers project to open the resource file in the resource editor.
2. Replace the existing resource strings for AnalyzerDescription, AnalyzerMessageFormat and AnalyzerTitle with new strings.

1. Replace the Initialize method implementation with the following:

public override void Initialize(AnalysisContext context)
{
   context.RegisterSyntaxTreeAction(syntaxTreeContext =>
   {
     // Iterate through all statements in the tree.
     var root = syntaxTreeContext.Tree.GetRoot(syntaxTreeContext.CancellationToken);
     foreach (var statement in root.DescendantNodes().OfType<StatementSyntax>())
     {
       // Skip analyzing block statements.
       if (statement is BlockSyntax)
       {
         continue;
       }

       // Report issue for all statements that are nested within a statement,
       // but not a block statement.
       if (statement.Parent is StatementSyntax && !(statement.Parent is BlockSyntax))
       {
         var diagnostic = Diagnostic.Create(Rule, statement.GetFirstToken().GetLocation());
         syntaxTreeContext.ReportDiagnostic(diagnostic);
       }
     }
   });
}

1. Click on Ctrl + F5 to start a new Visual Studio instance with the analyzer enabled.
2. In the new Visual Studio instance, create a new C# class library with the following code:

namespace ClassLibrary
{
  public class Class1
  {
    void Method(bool flag, int value)
    {
      while (flag)
      if (value > 0)
      System.Console.WriteLine(value);
    }
  }
}

1. Verify the analyzer diagnostic is neither reported for the method block for Method nor the while statement, but is reported for the if statement and System.Console.WriteLine invocation statement:

1. Now, add curly braces around the System.Console.WriteLine invocation statement and verify the only single warning is now reported for the if statement: