private static async Task <Document> GetTransformedDocumentAsync(Document document, Diagnostic diagnostic, CancellationToken cancellationToken)
        {
            var documentRoot = await document.GetSyntaxRootAsync(cancellationToken).ConfigureAwait(false);

            SyntaxNode syntax = documentRoot.FindNode(diagnostic.Location.SourceSpan);

            if (syntax == null)
            {
                return(document);
            }

            MethodDeclarationSyntax   methodDeclarationSyntax   = syntax.FirstAncestorOrSelf <MethodDeclarationSyntax>();
            DelegateDeclarationSyntax delegateDeclarationSyntax = syntax.FirstAncestorOrSelf <DelegateDeclarationSyntax>();

            if (methodDeclarationSyntax == null && delegateDeclarationSyntax == null)
            {
                return(document);
            }

            DocumentationCommentTriviaSyntax documentationComment =
                methodDeclarationSyntax?.GetDocumentationCommentTriviaSyntax()
                ?? delegateDeclarationSyntax?.GetDocumentationCommentTriviaSyntax();

            if (documentationComment == null)
            {
                return(document);
            }

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

            bool isTask;
            bool isAsynchronousTestMethod;

            if (methodDeclarationSyntax != null)
            {
                isTask = IsTaskReturningMethod(semanticModel, methodDeclarationSyntax, cancellationToken);
                isAsynchronousTestMethod = isTask && IsAsynchronousTestMethod(semanticModel, methodDeclarationSyntax, cancellationToken);
            }
            else
            {
                isTask = IsTaskReturningMethod(semanticModel, delegateDeclarationSyntax, cancellationToken);
                isAsynchronousTestMethod = false;
            }

            XmlNodeSyntax returnsElement = documentationComment.Content.GetFirstXmlElement(XmlCommentHelper.ReturnsXmlTag) as XmlNodeSyntax;

            if (returnsElement != null && !isTask)
            {
                // This code fix doesn't know how to do anything more than document Task-returning methods.
                return(document);
            }

            SyntaxList <XmlNodeSyntax> content = XmlSyntaxFactory.List();

            if (isTask)
            {
                content = content.Add(XmlSyntaxFactory.Text("A "));
                content = content.Add(XmlSyntaxFactory.SeeElement(SyntaxFactory.TypeCref(SyntaxFactory.ParseTypeName("global::System.Threading.Tasks.Task"))).WithAdditionalAnnotations(Simplifier.Annotation));
                string operationKind = isAsynchronousTestMethod ? "unit test" : "operation";
                content = content.Add(XmlSyntaxFactory.Text($" representing the asynchronous {operationKind}."));

                // wrap the generated content in a <placeholder> element for review.
                content = XmlSyntaxFactory.List(XmlSyntaxFactory.PlaceholderElement(content));
            }

            // Try to replace an existing <returns> element if the comment contains one. Otherwise, add it as a new element.
            SyntaxNode root = await document.GetSyntaxRootAsync(cancellationToken).ConfigureAwait(false);

            SyntaxNode newRoot;

            if (returnsElement != null)
            {
                XmlEmptyElementSyntax emptyElement = returnsElement as XmlEmptyElementSyntax;
                if (emptyElement != null)
                {
                    XmlElementSyntax updatedReturns = XmlSyntaxFactory.Element(XmlCommentHelper.ReturnsXmlTag, content)
                                                      .WithLeadingTrivia(returnsElement.GetLeadingTrivia())
                                                      .WithTrailingTrivia(returnsElement.GetTrailingTrivia());
                    newRoot = root.ReplaceNode(returnsElement, updatedReturns);
                }
                else
                {
                    XmlElementSyntax updatedReturns = ((XmlElementSyntax)returnsElement).WithContent(content);
                    newRoot = root.ReplaceNode(returnsElement, updatedReturns);
                }
            }
            else
            {
                string newLineText = document.Project.Solution.Workspace.Options.GetOption(FormattingOptions.NewLine, LanguageNames.CSharp);

                returnsElement = XmlSyntaxFactory.Element(XmlCommentHelper.ReturnsXmlTag, content);

                XmlNodeSyntax leadingNewLine = XmlSyntaxFactory.NewLine(newLineText);

                // HACK: The formatter isn't working when contents are added to an existing documentation comment, so we
                // manually apply the indentation from the last line of the existing comment to each new line of the
                // generated content.
                SyntaxTrivia exteriorTrivia = GetLastDocumentationCommentExteriorTrivia(documentationComment);
                if (!exteriorTrivia.Token.IsMissing)
                {
                    leadingNewLine = leadingNewLine.ReplaceExteriorTrivia(exteriorTrivia);
                    returnsElement = returnsElement.ReplaceExteriorTrivia(exteriorTrivia);
                }

                DocumentationCommentTriviaSyntax newDocumentationComment = documentationComment.WithContent(
                    documentationComment.Content.InsertRange(
                        documentationComment.Content.Count - 1,
                        XmlSyntaxFactory.List(leadingNewLine, returnsElement)));

                newRoot = root.ReplaceNode(documentationComment, newDocumentationComment);
            }

            return(document.WithSyntaxRoot(newRoot));
        }
Example #2
0
        private async Task <Document> GetTransformedDocumentAsync(Document document, Diagnostic diagnostic, CancellationToken cancellationToken)
        {
            var documentRoot = await document.GetSyntaxRootAsync(cancellationToken).ConfigureAwait(false);

            SyntaxNode syntax = documentRoot.FindNode(diagnostic.Location.SourceSpan);

            if (syntax == null)
            {
                return(document);
            }

            PropertyDeclarationSyntax propertyDeclarationSyntax = syntax.FirstAncestorOrSelf <PropertyDeclarationSyntax>();

            if (propertyDeclarationSyntax == null)
            {
                return(document);
            }

            DocumentationCommentTriviaSyntax documentationComment = propertyDeclarationSyntax.GetDocumentationCommentTriviaSyntax();

            if (documentationComment == null)
            {
                return(document);
            }

            if (!(documentationComment.Content.GetFirstXmlElement(XmlCommentHelper.SummaryXmlTag) is XmlElementSyntax summaryElement))
            {
                return(document);
            }

            SyntaxList <XmlNodeSyntax> summaryContent = summaryElement.Content;

            if (!this.TryRemoveSummaryPrefix(ref summaryContent, "Gets or sets "))
            {
                if (!this.TryRemoveSummaryPrefix(ref summaryContent, "Gets "))
                {
                    this.TryRemoveSummaryPrefix(ref summaryContent, "Sets ");
                }
            }

            SyntaxList <XmlNodeSyntax> content = summaryContent.WithoutFirstAndLastNewlines();

            if (!string.IsNullOrWhiteSpace(content.ToFullString()))
            {
                // wrap the content in a <placeholder> element for review
                content = XmlSyntaxFactory.List(XmlSyntaxFactory.PlaceholderElement(content));
            }

            string newLineText = document.Project.Solution.Workspace.Options.GetOption(FormattingOptions.NewLine, LanguageNames.CSharp);

            XmlElementSyntax valueElement = XmlSyntaxFactory.MultiLineElement(XmlCommentHelper.ValueXmlTag, newLineText, content);

            XmlNodeSyntax leadingNewLine = XmlSyntaxFactory.NewLine(newLineText);

            // HACK: The formatter isn't working when contents are added to an existing documentation comment, so we
            // manually apply the indentation from the last line of the existing comment to each new line of the
            // generated content.
            SyntaxTrivia exteriorTrivia = GetLastDocumentationCommentExteriorTrivia(documentationComment);

            if (!exteriorTrivia.Token.IsMissing)
            {
                leadingNewLine = leadingNewLine.ReplaceExteriorTrivia(exteriorTrivia);
                valueElement   = valueElement.ReplaceExteriorTrivia(exteriorTrivia);
            }

            // Try to replace an existing <value> element if the comment contains one. Otherwise, add it as a new element.
            SyntaxNode root = await document.GetSyntaxRootAsync(cancellationToken).ConfigureAwait(false);

            SyntaxNode    newRoot;
            XmlNodeSyntax existingValue = documentationComment.Content.GetFirstXmlElement(XmlCommentHelper.ValueXmlTag);

            if (existingValue != null)
            {
                newRoot = root.ReplaceNode(existingValue, valueElement);
            }
            else
            {
                DocumentationCommentTriviaSyntax newDocumentationComment = documentationComment.WithContent(
                    documentationComment.Content.InsertRange(
                        documentationComment.Content.Count - 1,
                        XmlSyntaxFactory.List(leadingNewLine, valueElement)));

                newRoot = root.ReplaceNode(documentationComment, newDocumentationComment);
            }

            return(document.WithSyntaxRoot(newRoot));
        }
        public void TestPlaceholderElement()
        {
            string expected = "<placeholder>Content.</placeholder>";

            Assert.Equal(expected, XmlSyntaxFactory.PlaceholderElement(XmlSyntaxFactory.Text("Content.")).ToFullString());
        }