예제 #1
0
        public static void Analyze(SyntaxNodeAnalysisContext context, AssignmentExpressionSyntax assignment)
        {
            ExpressionSyntax right = assignment.Right;

            if (right?.IsKind(SyntaxKind.ObjectCreationExpression) == true)
            {
                var objectCreation = (ObjectCreationExpressionSyntax)right;

                SemanticModel     semanticModel     = context.SemanticModel;
                CancellationToken cancellationToken = context.CancellationToken;

                ITypeSymbol typeSymbol = semanticModel.GetTypeSymbol(objectCreation, cancellationToken);

                if (typeSymbol != null &&
                    SymbolUtility.IsEventHandlerOrConstructedFromEventHandlerOfT(typeSymbol, semanticModel))
                {
                    ArgumentListSyntax argumentList = objectCreation.ArgumentList;

                    if (argumentList != null)
                    {
                        SeparatedSyntaxList <ArgumentSyntax> arguments = argumentList.Arguments;

                        if (arguments.Count == 1)
                        {
                            ArgumentSyntax argument = arguments.First();

                            ExpressionSyntax expression = argument.Expression;

                            if (expression != null &&
                                semanticModel.GetSymbol(expression, cancellationToken) is IMethodSymbol)
                            {
                                ExpressionSyntax left = assignment.Left;

                                if (left?.IsMissing == false &&
                                    semanticModel.GetSymbol(left, cancellationToken)?.IsEvent() == true &&
                                    !objectCreation.SpanContainsDirectives())
                                {
                                    context.ReportDiagnostic(DiagnosticDescriptors.RemoveRedundantDelegateCreation, right);

                                    context.ReportToken(DiagnosticDescriptors.RemoveRedundantDelegateCreationFadeOut, objectCreation.NewKeyword);
                                    context.ReportNode(DiagnosticDescriptors.RemoveRedundantDelegateCreationFadeOut, objectCreation.Type);
                                    context.ReportParentheses(DiagnosticDescriptors.RemoveRedundantDelegateCreationFadeOut, objectCreation.ArgumentList);
                                }
                            }
                        }
                    }
                }
            }
        }