Exemple #1
0
        static CodeAction HandleNegatedCase(BaseRefactoringContext ctx, IfElseStatement ifElseStatement, Match match, out IsExpression isExpression, out int foundCastCount)
        {
            foundCastCount = 0;
            var outerIs = match.Get <Expression>("isExpression").Single();

            isExpression = AlUtil.GetInnerMostExpression(outerIs) as IsExpression;
            var obj        = AlUtil.GetInnerMostExpression(isExpression.Expression);
            var castToType = isExpression.Type;

            var cast = new Choice {
                PatternHelper.OptionalParentheses(PatternHelper.OptionalParentheses(obj.Clone()).CastTo(castToType.Clone())),
                PatternHelper.OptionalParentheses(PatternHelper.OptionalParentheses(obj.Clone()).CastAs(castToType.Clone()))
            };

            var rr = ctx.Resolve(castToType);

            if (rr == null || rr.IsError || rr.Type.IsReferenceType == false)
            {
                return(null);
            }
            var foundCasts = ifElseStatement.GetParent <BlockStatement>().DescendantNodes(n => n.StartLocation >= ifElseStatement.StartLocation && !cast.IsMatch(n)).Where(n => cast.IsMatch(n)).ToList();

            foundCastCount = foundCasts.Count;

            return(new CodeAction(ctx.TranslateString("Use 'as' and check for null"), script => {
                var varName = ctx.GetNameProposal(CreateMethodDeclarationAction.GuessNameFromType(rr.Type), ifElseStatement.StartLocation);
                var varDec = new VariableDeclarationStatement(new PrimitiveType("var"), varName, new AsExpression(obj.Clone(), castToType.Clone()));
                var binaryOperatorIdentifier = new IdentifierExpression(varName);
                var binaryOperatorExpression = new BinaryOperatorExpression(binaryOperatorIdentifier, BinaryOperatorType.Equality, new NullReferenceExpression());
                var linkedNodes = new List <AstNode>();
                linkedNodes.Add(varDec.Variables.First().NameToken);
                linkedNodes.Add(binaryOperatorIdentifier);
                if (IsEmbeddedStatement(ifElseStatement))
                {
                    var block = new BlockStatement();
                    block.Add(varDec);
                    var newIf = (IfElseStatement)ifElseStatement.Clone();
                    newIf.Condition = binaryOperatorExpression;
                    foreach (var node in newIf.DescendantNodesAndSelf(n => !cast.IsMatch(n)).Where(n => cast.IsMatch(n)))
                    {
                        var id = new IdentifierExpression(varName);
                        linkedNodes.Add(id);
                        node.ReplaceWith(id);
                    }
                    block.Add(newIf);
                    script.Replace(ifElseStatement, block);
                }
                else
                {
                    script.InsertBefore(ifElseStatement, varDec);
                    script.Replace(ifElseStatement.Condition, binaryOperatorExpression);
                    foreach (var c in foundCasts)
                    {
                        var id = new IdentifierExpression(varName);
                        linkedNodes.Add(id);
                        script.Replace(c, id);
                    }
                }
                script.Link(linkedNodes);
            }, isExpression.IsToken));
        }