コード例 #1
0
        private SyntaxResult <SyntaxNode> TranslateStatement_Return(ReturnStatement returnStatement, TranslatorState state)
        {
            ReturnStatementSyntax returnStatementSyntax = SyntaxFactory.ReturnStatement();

            if (returnStatement.Expression != null)
            {
                var expression = TranslateExpression(returnStatement.Expression, state);

                if (expression.IsError)
                {
                    returnStatementSyntax = returnStatementSyntax.WithTrailingTrivia(expression.Errors);
                }
                else
                {
                    returnStatementSyntax = returnStatementSyntax.WithExpression(expression.Syntax);
                }
            }

            return(returnStatementSyntax);
        }
        private static async Task <StatementListInfo> RefactorAsync <TStatement>(
            Document document,
            TStatement statement,
            StatementListInfo statementsInfo,
            Func <TStatement, TStatement> createNewStatement,
            int count,
            bool removeReturnStatement,
            CancellationToken cancellationToken) where TStatement : StatementSyntax
        {
            int statementIndex = statementsInfo.IndexOf(statement);

            var returnStatement = (ReturnStatementSyntax)statementsInfo[statementIndex + 1];

            ExpressionSyntax returnExpression    = returnStatement.Expression;
            ExpressionSyntax newReturnExpression = null;
            SyntaxTriviaList newTrailingTrivia   = default;

            SemanticModel semanticModel = await document.GetSemanticModelAsync(cancellationToken).ConfigureAwait(false);

            ISymbol symbol = semanticModel.GetSymbol(returnExpression, cancellationToken);

            if (symbol.Kind == SymbolKind.Local &&
                statementIndex > 0 &&
                statementsInfo[statementIndex - 1] is LocalDeclarationStatementSyntax localDeclarationStatement &&
                !localDeclarationStatement.ContainsDiagnostics &&
                !localDeclarationStatement.SpanOrTrailingTriviaContainsDirectives() &&
                !statement.GetLeadingTrivia().Any(f => f.IsDirective))
            {
                SeparatedSyntaxList <VariableDeclaratorSyntax> declarators = localDeclarationStatement.Declaration.Variables;

                VariableDeclaratorSyntax declarator = declarators.FirstOrDefault(f => semanticModel.GetDeclaredSymbol(f, cancellationToken)?.Equals(symbol) == true);

                if (declarator != null)
                {
                    ExpressionSyntax value = declarator.Initializer?.Value;

                    if (removeReturnStatement || value != null)
                    {
                        IEnumerable <ReferencedSymbol> referencedSymbols = await SymbolFinder.FindReferencesAsync(symbol, document.Solution(), cancellationToken).ConfigureAwait(false);

                        if (referencedSymbols.First().Locations.Count() == count + 1)
                        {
                            newReturnExpression = value;

                            if (declarators.Count == 1)
                            {
                                if (!removeReturnStatement &&
                                    returnStatement.GetTrailingTrivia().IsEmptyOrWhitespace())
                                {
                                    SyntaxTriviaList trailingTrivia = localDeclarationStatement.GetTrailingTrivia();

                                    if (trailingTrivia
                                        .SkipWhile(f => f.IsWhitespaceTrivia())
                                        .FirstOrDefault()
                                        .IsKind(SyntaxKind.SingleLineCommentTrivia))
                                    {
                                        newTrailingTrivia = trailingTrivia;
                                    }
                                }

                                SyntaxRemoveOptions removeOptions = SyntaxRefactorings.GetRemoveOptions(localDeclarationStatement);

                                if (newTrailingTrivia.Any())
                                {
                                    removeOptions &= ~SyntaxRemoveOptions.KeepTrailingTrivia;
                                }

                                statementsInfo = statementsInfo.RemoveNode(localDeclarationStatement, removeOptions);
                                statementIndex--;
                            }
                            else
                            {
                                statementsInfo = statementsInfo.ReplaceNode(localDeclarationStatement, localDeclarationStatement.RemoveNode(declarator, SyntaxRefactorings.GetRemoveOptions(declarator)));
                            }

                            returnStatement = (ReturnStatementSyntax)statementsInfo[statementIndex + 1];
                        }
                    }
                }
            }

            if (removeReturnStatement)
            {
                statementsInfo = statementsInfo.RemoveNode(returnStatement, SyntaxRefactorings.GetRemoveOptions(returnStatement));
            }
            else if (newReturnExpression != null)
            {
                ReturnStatementSyntax newReturnStatement = returnStatement.WithExpression(newReturnExpression.WithTriviaFrom(returnExpression));

                if (newTrailingTrivia.Any())
                {
                    newReturnStatement = newReturnStatement.WithTrailingTrivia(newTrailingTrivia);
                }

                statementsInfo = statementsInfo.ReplaceNode(returnStatement, newReturnStatement);
            }

            StatementSyntax oldNode = statementsInfo[statementIndex];

            TStatement newNode = createNewStatement((TStatement)oldNode).WithFormatterAnnotation();

            return(statementsInfo.ReplaceNode(oldNode, newNode));
        }