protected void GetDiagnosticsForNode(SyntaxNode node, SemanticModel model, Action<Diagnostic> addDiagnostic)
 {
     var type = model.GetTypeInfo(node).Type;
     if (type != null && TypeHasWeakIdentity(type, model))
     {
         addDiagnostic(node.CreateDiagnostic(Rule, type.ToDisplayString()));
     }
 }
 protected Diagnostic CreateDiagnostic(SyntaxNode node)
 {
     return node.CreateDiagnostic(Rule);
 }