Support URL navigation for href in Quick Info

src/Compilers/Core/Portable/InternalUtilities/DocumentationCommentXmlNames.cs

@@ -37,6 +37,7 @@ internal static class DocumentationCommentXmlNames
         public const string ValueElementName = "value";
 
         public const string CrefAttributeName = "cref";
+        public const string HrefAttributeName = "href";
         public const string FileAttributeName = "file";
         public const string InstanceAttributeName = "instance";
         public const string LangwordAttributeName = "langword";

src/EditorFeatures/Core/Implementation/IntelliSense/AsyncCompletion/CompletionSource.cs

@@ -294,15 +294,16 @@ public async Task<object> GetDescriptionAsync(IAsyncCompletionSession session, V
             }
 
             var service = document.GetLanguageService<CompletionService>();
-
             if (service == null)
             {
                 return null;
             }
 
+            var navigateToLinkService = document.Project.Solution.Workspace.Services.GetRequiredService<INavigateToLinkService>();
+
             var description = await service.GetDescriptionAsync(document, roslynItem, cancellationToken).ConfigureAwait(false);
 
-            var elements = IntelliSense.Helpers.BuildClassifiedTextElements(description.TaggedParts).ToArray();
+            var elements = IntelliSense.Helpers.BuildClassifiedTextElements(description.TaggedParts, navigateToLinkService).ToArray();
             if (elements.Length == 0)
             {
                 return new ClassifiedTextElement();

src/EditorFeatures/Core/Implementation/IntelliSense/Helpers.cs

 // Copyright (c) Microsoft.  All Rights Reserved.  Licensed under the Apache License, Version 2.0.  See License.txt in the project root for license information.
 
+using System;
 using System.Collections.Generic;
 using System.Collections.Immutable;
 using System.Linq;
+using System.Threading;
 using Microsoft.CodeAnalysis.Classification;
 using Microsoft.VisualStudio.Text.Adornments;
 using Roslyn.Utilities;
@@ -11,13 +13,13 @@ namespace Microsoft.CodeAnalysis.Editor.Implementation.IntelliSense
 {
     internal static class Helpers
     {
-        internal static IEnumerable<object> BuildClassifiedTextElements(ImmutableArray<TaggedText> taggedTexts)
+        internal static IEnumerable<object> BuildClassifiedTextElements(ImmutableArray<TaggedText> taggedTexts, INavigateToLinkService navigateToLinkService)
         {
             var index = 0;
-            return BuildClassifiedTextElements(taggedTexts, ref index);
+            return BuildClassifiedTextElements(taggedTexts, ref index, navigateToLinkService);
         }
 
-        private static IReadOnlyCollection<object> BuildClassifiedTextElements(ImmutableArray<TaggedText> taggedTexts, ref int index)
+        private static IReadOnlyCollection<object> BuildClassifiedTextElements(ImmutableArray<TaggedText> taggedTexts, ref int index, INavigateToLinkService navigateToLinkService)
         {
             // This method produces a sequence of zero or more paragraphs
             var paragraphs = new List<object>();
@@ -41,7 +43,7 @@ private static IReadOnlyCollection<object> BuildClassifiedTextElements(Immutable
                     }
 
                     index++;
-                    var nestedElements = BuildClassifiedTextElements(taggedTexts, ref index);
+                    var nestedElements = BuildClassifiedTextElements(taggedTexts, ref index, navigateToLinkService);
                     if (nestedElements.Count <= 1)
                     {
                         currentParagraph.Add(new ContainerElement(
@@ -108,7 +110,15 @@ private static IReadOnlyCollection<object> BuildClassifiedTextElements(Immutable
                 {
                     // This is tagged text getting added to the current line we are building.
                     var style = GetClassifiedTextRunStyle(part.Style);
-                    currentRuns.Add(new ClassifiedTextRun(part.Tag.ToClassificationTypeName(), part.Text, style));
+                    if (part.NavigationTarget is object)
+                    {
+                        var tooltip = part.NavigationTarget;
+                        currentRuns.Add(new ClassifiedTextRun(part.Tag.ToClassificationTypeName(), part.Text, () => NavigateToQuickInfoTarget(tooltip, navigateToLinkService), tooltip, style));
+                    }
+                    else
+                    {
+                        currentRuns.Add(new ClassifiedTextRun(part.Tag.ToClassificationTypeName(), part.Text, style));
+                    }
                 }
             }
 
@@ -127,6 +137,15 @@ private static IReadOnlyCollection<object> BuildClassifiedTextElements(Immutable
             return paragraphs;
         }
 
+        private static void NavigateToQuickInfoTarget(string navigationTarget, INavigateToLinkService navigateToLinkService)
+        {
+            if (Uri.TryCreate(navigationTarget, UriKind.Absolute, out var absoluteUri))
+            {
+                navigateToLinkService.TryNavigateToLinkAsync(absoluteUri, CancellationToken.None);
+                return;
+            }
+        }
+
         private static ClassifiedTextRunStyle GetClassifiedTextRunStyle(TaggedTextStyle style)
         {
             var result = ClassifiedTextRunStyle.Plain;

src/EditorFeatures/Core/Implementation/IntelliSense/QuickInfo/IntellisenseQuickInfoBuilder.cs

@@ -43,10 +43,11 @@ internal static class IntellisenseQuickInfoBuilder
 
             var elements = new List<object>();
             var descSection = quickInfoItem.Sections.FirstOrDefault(s => s.Kind == QuickInfoSectionKinds.Description);
+            var navigateToLinkService = document.Project.Solution.Workspace.Services.GetRequiredService<INavigateToLinkService>();
             if (descSection != null)
             {
                 var isFirstElement = true;
-                foreach (var element in Helpers.BuildClassifiedTextElements(descSection.TaggedParts))
+                foreach (var element in Helpers.BuildClassifiedTextElements(descSection.TaggedParts, navigateToLinkService))
                 {
                     if (isFirstElement)
                     {
@@ -68,7 +69,7 @@ internal static class IntellisenseQuickInfoBuilder
             if (documentationCommentSection != null)
             {
                 var isFirstElement = true;
-                foreach (var element in Helpers.BuildClassifiedTextElements(documentationCommentSection.TaggedParts))
+                foreach (var element in Helpers.BuildClassifiedTextElements(documentationCommentSection.TaggedParts, navigateToLinkService))
                 {
                     if (isFirstElement)
                     {
@@ -92,7 +93,7 @@ internal static class IntellisenseQuickInfoBuilder
             // Add the remaining sections as Stacked style
             elements.AddRange(
                 quickInfoItem.Sections.Where(s => s.Kind != QuickInfoSectionKinds.Description && s.Kind != QuickInfoSectionKinds.DocumentationComments)
-                                      .SelectMany(s => Helpers.BuildClassifiedTextElements(s.TaggedParts)));
+                                      .SelectMany(s => Helpers.BuildClassifiedTextElements(s.TaggedParts, navigateToLinkService)));
 
             // build text for RelatedSpan
             if (quickInfoItem.RelatedSpans.Any())

src/EditorFeatures/Test2/IntelliSense/AbstractIntellisenseQuickInfoBuilderTests.vb

@@ -189,6 +189,11 @@ Namespace Microsoft.CodeAnalysis.Editor.UnitTests.IntelliSense
             If classifiedTextRun IsNot Nothing Then
                 Dim classification = GetKnownClassification(classifiedTextRun.ClassificationTypeName)
                 result.Append($"{classification}, ""{classifiedTextRun.Text.Replace("""", """""")}""")
+                If classifiedTextRun.NavigationAction IsNot Nothing OrElse Not String.IsNullOrEmpty(classifiedTextRun.Tooltip) Then
+                    Dim tooltip = If(classifiedTextRun.Tooltip IsNot Nothing, $"""{classifiedTextRun.Tooltip.Replace("""", """""")}""", "Nothing")
+                    result.Append($", navigationAction:=Sub() Return, {tooltip}")
+                End If
+
                 If classifiedTextRun.Style <> ClassifiedTextRunStyle.Plain Then
                     result.Append($", {TextRunStyleToString(classifiedTextRun.Style)}")
                 End If

src/EditorFeatures/Test2/IntelliSense/IntellisenseQuickInfoBuilderTests_Links.vb

+' Copyright (c) Microsoft.  All Rights Reserved.  Licensed under the Apache License, Version 2.0.  See License.txt in the project root for license information.
+
+Imports Microsoft.CodeAnalysis.Classification
+Imports Microsoft.VisualStudio.Core.Imaging
+Imports Microsoft.VisualStudio.Imaging
+Imports Microsoft.VisualStudio.Text.Adornments
+
+Namespace Microsoft.CodeAnalysis.Editor.UnitTests.IntelliSense
+    Public Class IntellisenseQuickInfoBuilderTests_Links
+        Inherits AbstractIntellisenseQuickInfoBuilderTests
+
+        <WpfTheory, Trait(Traits.Feature, Traits.Features.QuickInfo)>
+        <InlineData("see")>
+        <InlineData("a")>
+        Public Async Sub QuickInfoForPlainHyperlink(tag As String)
+            Dim workspace =
+                <Workspace>
+                    <Project Language="C#" CommonReferences="true">
+                        <Document>
+                            using System.Threading;
+                            class MyClass {
+                                /// &lt;summary&gt;
+                                /// This contains a link to &lt;<%= tag %> href="https://github.com/dotnet/roslyn"/&gt;.
+                                /// &lt;/summary&gt;
+                                void MyMethod() {
+                                    MyM$$ethod();
+                                }
+                            }
+                        </Document>
+                    </Project>
+                </Workspace>
+
+            Dim intellisenseQuickInfo = Await GetQuickInfoItemAsync(workspace, LanguageNames.CSharp)
+
+            Dim expected = New ContainerElement(
+                ContainerElementStyle.Stacked Or ContainerElementStyle.VerticalPadding,
+                New ContainerElement(
+                    ContainerElementStyle.Stacked,
+                    New ContainerElement(
+                        ContainerElementStyle.Wrapped,
+                        New ImageElement(New ImageId(KnownImageIds.ImageCatalogGuid, KnownImageIds.MethodPrivate)),
+                        New ClassifiedTextElement(
+                            New ClassifiedTextRun(ClassificationTypeNames.Keyword, "void"),
+                            New ClassifiedTextRun(ClassificationTypeNames.WhiteSpace, " "),
+                            New ClassifiedTextRun(ClassificationTypeNames.ClassName, "MyClass"),
+                            New ClassifiedTextRun(ClassificationTypeNames.Punctuation, "."),
+                            New ClassifiedTextRun(ClassificationTypeNames.MethodName, "MyMethod"),
+                            New ClassifiedTextRun(ClassificationTypeNames.Punctuation, "("),
+                            New ClassifiedTextRun(ClassificationTypeNames.Punctuation, ")"))),
+                    New ClassifiedTextElement(
+                        New ClassifiedTextRun(ClassificationTypeNames.Text, "This contains a link to"),
+                        New ClassifiedTextRun(ClassificationTypeNames.WhiteSpace, " "),
+                        New ClassifiedTextRun(ClassificationTypeNames.Text, "https://github.com/dotnet/roslyn", navigationAction:=Sub() Return, "https://github.com/dotnet/roslyn"),
+                        New ClassifiedTextRun(ClassificationTypeNames.Text, "."))))
+
+            AssertEqualAdornments(expected, intellisenseQuickInfo.Item)
+        End Sub
+
+        <WpfTheory, Trait(Traits.Feature, Traits.Features.QuickInfo)>
+        <InlineData("see")>
+        <InlineData("a")>
+        Public Async Sub QuickInfoForHyperlinkWithText(tag As String)
+            Dim workspace =
+                <Workspace>
+                    <Project Language="C#" CommonReferences="true">
+                        <Document>
+                            using System.Threading;
+                            class MyClass {
+                                /// &lt;summary&gt;
+                                /// This contains a link to &lt;<%= tag %> href="https://github.com/dotnet/roslyn"&gt;dotnet/roslyn&lt;/<%= tag %>&gt;.
+                                /// &lt;/summary&gt;
+                                void MyMethod() {
+                                    MyM$$ethod();
+                                }
+                            }
+                        </Document>
+                    </Project>
+                </Workspace>
+
+            Dim intellisenseQuickInfo = Await GetQuickInfoItemAsync(workspace, LanguageNames.CSharp)
+
+            Dim expected = New ContainerElement(
+                ContainerElementStyle.Stacked Or ContainerElementStyle.VerticalPadding,
+                New ContainerElement(
+                    ContainerElementStyle.Stacked,
+                    New ContainerElement(
+                        ContainerElementStyle.Wrapped,
+                        New ImageElement(New ImageId(KnownImageIds.ImageCatalogGuid, KnownImageIds.MethodPrivate)),
+                        New ClassifiedTextElement(
+                            New ClassifiedTextRun(ClassificationTypeNames.Keyword, "void"),
+                            New ClassifiedTextRun(ClassificationTypeNames.WhiteSpace, " "),
+                            New ClassifiedTextRun(ClassificationTypeNames.ClassName, "MyClass"),
+                            New ClassifiedTextRun(ClassificationTypeNames.Punctuation, "."),
+                            New ClassifiedTextRun(ClassificationTypeNames.MethodName, "MyMethod"),
+                            New ClassifiedTextRun(ClassificationTypeNames.Punctuation, "("),
+                            New ClassifiedTextRun(ClassificationTypeNames.Punctuation, ")"))),
+                    New ClassifiedTextElement(
+                        New ClassifiedTextRun(ClassificationTypeNames.Text, "This contains a link to"),
+                        New ClassifiedTextRun(ClassificationTypeNames.WhiteSpace, " "),
+                        New ClassifiedTextRun(ClassificationTypeNames.Text, "dotnet/roslyn", navigationAction:=Sub() Return, "https://github.com/dotnet/roslyn"),
+                        New ClassifiedTextRun(ClassificationTypeNames.Text, "."))))
+
+            AssertEqualAdornments(expected, intellisenseQuickInfo.Item)
+        End Sub
+    End Class
+End Namespace

src/Features/Core/Portable/Common/TaggedText.cs

@@ -31,13 +31,19 @@ namespace Microsoft.CodeAnalysis
         /// </summary>
         internal TaggedTextStyle Style { get; }
 
+        /// <summary>
+        /// Gets the navigation target for the text, or <see langword="null"/> if the text does not have a navigation
+        /// target.
+        /// </summary>
+        internal string NavigationTarget { get; }
+
         /// <summary>
         /// Creates a new instance of <see cref="TaggedText"/>
         /// </summary>
         /// <param name="tag">A descriptive tag from <see cref="TextTags"/>.</param>
         /// <param name="text">The actual text to be displayed.</param>
         public TaggedText(string tag, string text)
-            : this(tag, text, TaggedTextStyle.None)
+            : this(tag, text, TaggedTextStyle.None, navigationTarget: null)
         {
         }
 
@@ -47,11 +53,13 @@ public TaggedText(string tag, string text)
         /// <param name="tag">A descriptive tag from <see cref="TextTags"/>.</param>
         /// <param name="text">The actual text to be displayed.</param>
         /// <param name="style">The style(s) to apply to the text.</param>
-        internal TaggedText(string tag, string text, TaggedTextStyle style)
+        /// <param name="navigationTarget">The navigation target for the text, or <see langword="null"/> if the text does not have a navigation target.</param>
+        internal TaggedText(string tag, string text, TaggedTextStyle style, string navigationTarget)
         {
             Tag = tag ?? throw new ArgumentNullException(nameof(tag));
             Text = text ?? throw new ArgumentNullException(nameof(text));
             Style = style;
+            NavigationTarget = navigationTarget;
         }
 
         public override string ToString()
@@ -73,7 +81,7 @@ public static ImmutableArray<TaggedText> ToTaggedText(this IEnumerable<SymbolDis
             }
 
             return displayParts.SelectAsArray(d =>
-                new TaggedText(SymbolDisplayPartKindTags.GetTag(d.Kind), d.ToString(), style));
+                new TaggedText(SymbolDisplayPartKindTags.GetTag(d.Kind), d.ToString(), style, navigationTarget: null));
         }
 
         public static string JoinText(this ImmutableArray<TaggedText> values)

src/Features/Core/Portable/DocumentationComments/AbstractDocumentationCommentFormattingService.cs

@@ -31,10 +31,12 @@ private class FormatterState
 
             internal readonly List<TaggedText> Builder = new List<TaggedText>();
             private readonly List<(DocumentationCommentListType type, int index, bool renderedItem)> _listStack = new List<(DocumentationCommentListType type, int index, bool renderedItem)>();
+            private readonly Stack<string> _navigationTargetStack = new Stack<string>();
             private readonly Stack<TaggedTextStyle> _styleStack = new Stack<TaggedTextStyle>();
 
             public FormatterState()
             {
+                _navigationTargetStack.Push(null);
                 _styleStack.Push(TaggedTextStyle.None);
             }
 
@@ -51,6 +53,7 @@ public bool AtBeginning
 
             public SymbolDisplayFormat Format { get; internal set; }
 
+            internal string NavigationTarget => _navigationTargetStack.Peek();
             internal TaggedTextStyle Style => _styleStack.Peek();
 
             public void AppendSingleSpace()
@@ -62,7 +65,7 @@ public void AppendString(string s)
             {
                 EmitPendingChars();
 
-                Builder.Add(new TaggedText(TextTags.Text, s, Style));
+                Builder.Add(new TaggedText(TextTags.Text, s, Style, NavigationTarget));
 
                 _anyNonWhitespaceSinceLastPara = true;
             }
@@ -115,6 +118,16 @@ public void PopList()
                 MarkBeginOrEndPara();
             }
 
+            public void PushNavigationTarget(string navigationTarget)
+            {
+                _navigationTargetStack.Push(navigationTarget);
+            }
+
+            public void PopNavigationTarget()
+            {
+                _navigationTargetStack.Pop();
+            }
+
             public void PushStyle(TaggedTextStyle style)
             {
                 _styleStack.Push(_styleStack.Peek() | style);
@@ -272,9 +285,11 @@ private static void AppendTextFromNode(FormatterState state, XNode node, Compila
 
             var name = element.Name.LocalName;
             var needPopStyle = false;
+            string navigationTarget = null;
 
             if (name == DocumentationCommentXmlNames.SeeElementName ||
-                name == DocumentationCommentXmlNames.SeeAlsoElementName)
+                name == DocumentationCommentXmlNames.SeeAlsoElementName ||
+                name == "a")
             {
                 if (element.IsEmpty || element.FirstNode == null)
                 {
@@ -285,6 +300,14 @@ private static void AppendTextFromNode(FormatterState state, XNode node, Compila
 
                     return;
                 }
+                else
+                {
+                    navigationTarget = GetNavigationTarget(element);
+                    if (navigationTarget is object)
+                    {
+                        state.PushNavigationTarget(navigationTarget);
+                    }
+                }
             }
             else if (name == DocumentationCommentXmlNames.ParameterReferenceElementName ||
                      name == DocumentationCommentXmlNames.TypeParameterReferenceElementName)
@@ -381,6 +404,11 @@ private static void AppendTextFromNode(FormatterState state, XNode node, Compila
                 state.PopStyle();
             }
 
+            if (navigationTarget is object)
+            {
+                state.PopNavigationTarget();
+            }
+
             if (name == DocumentationCommentXmlNames.TermElementName)
             {
                 state.AppendSingleSpace();
@@ -388,6 +416,17 @@ private static void AppendTextFromNode(FormatterState state, XNode node, Compila
             }
         }
 
+        private static string GetNavigationTarget(XElement element)
+        {
+            var hrefAttribute = element.Attribute(DocumentationCommentXmlNames.HrefAttributeName);
+            if (hrefAttribute is object)
+            {
+                return hrefAttribute.Value;
+            }
+
+            return null;
+        }
+
         private static void AppendTextFromAttribute(FormatterState state, XElement element, XAttribute attribute, string attributeNameToParse, SymbolDisplayPartKind kind)
         {
             var attributeName = attribute.Name.LocalName;
@@ -401,7 +440,12 @@ private static void AppendTextFromAttribute(FormatterState state, XElement eleme
                 var displayKind = attributeName == DocumentationCommentXmlNames.LangwordAttributeName
                     ? TextTags.Keyword
                     : TextTags.Text;
-                state.AppendParts(SpecializedCollections.SingletonEnumerable(new TaggedText(displayKind, attribute.Value, state.Style)));
+                var text = attribute.Value;
+                var style = state.Style;
+                var navigationTarget = attributeName == DocumentationCommentXmlNames.HrefAttributeName
+                    ? attribute.Value
+                    : null;
+                state.AppendParts(SpecializedCollections.SingletonEnumerable(new TaggedText(displayKind, text, style, navigationTarget)));
             }
         }