Revert "Merge pull request #18972 from CyrusNajmabadi/docHighlights2"

This reverts commit 8262112e, reversing
changes made to 837ca214.

src/EditorFeatures/CSharp/CSharpEditorFeatures.csproj

@@ -136,12 +136,14 @@
     <Compile Include="Highlighting\KeywordHighlighters\UnsafeStatementHighlighter.cs" />
     <Compile Include="Highlighting\KeywordHighlighters\UsingStatementHighlighter.cs" />
     <Compile Include="Highlighting\KeywordHighlighters\YieldStatementHighlighter.cs" />
+    <Compile Include="HighlightReferences\CSharpDocumentHighlightsService.cs" />
     <Compile Include="InlineRename\CSharpEditorInlineRenameService.cs" />
     <Compile Include="LanguageServices\CSharpContentTypeLanguageService.cs" />
     <Compile Include="LineSeparators\CSharpLineSeparatorService.cs" />
     <Compile Include="NavigationBar\CSharpNavigationBarItemService.cs" />
     <Compile Include="QuickInfo\SemanticQuickInfoProvider.cs" />
     <Compile Include="QuickInfo\SyntacticQuickInfoProvider.cs" />
+    <Compile Include="ReferenceHighlighting\ReferenceHighlightingAdditionalReferenceProvider.cs" />
     <Compile Include="RenameTracking\CSharpRenameTrackingCodeFixProvider.cs" />
     <Compile Include="RenameTracking\CSharpRenameTrackingLanguageHeuristicsService.cs" />
     <Compile Include="SplitStringLiteral\SplitStringLiteralCommandHandler.cs" />

src/EditorFeatures/CSharp/HighlightReferences/CSharpDocumentHighlightsService.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.Composition;
+using Microsoft.CodeAnalysis.Editor.Implementation.ReferenceHighlighting;
+using Microsoft.CodeAnalysis.Host.Mef;
+
+namespace Microsoft.CodeAnalysis.Editor.CSharp.HighlightReferences
+{
+    [ExportLanguageService(typeof(IDocumentHighlightsService), LanguageNames.CSharp), Shared]
+    internal class CSharpDocumentHighlightsService : AbstractDocumentHighlightsService
+    {
+    }
+}

src/Features/CSharp/Portable/DocumentHighlighting/CSharpDocumentHighlightsService.cs → src/EditorFeatures/CSharp/ReferenceHighlighting/ReferenceHighlightingAdditionalReferenceProvider.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.Collections.Immutable;
+using System.Collections.Generic;
 using System.Composition;
 using System.Linq;
 using System.Threading;
 using System.Threading.Tasks;
 using Microsoft.CodeAnalysis.CSharp.Syntax;
-using Microsoft.CodeAnalysis.DocumentHighlighting;
+using Microsoft.CodeAnalysis.Editor.Implementation.ReferenceHighlighting;
 using Microsoft.CodeAnalysis.Host.Mef;
+using Roslyn.Utilities;
 
-namespace Microsoft.CodeAnalysis.CSharp.DocumentHighlighting
+namespace Microsoft.CodeAnalysis.Editor.CSharp.ReferenceHighlighting
 {
-    [ExportLanguageService(typeof(IDocumentHighlightsService), LanguageNames.CSharp), Shared]
-    internal class CSharpDocumentHighlightsService : AbstractDocumentHighlightsService
+    [ExportLanguageService(typeof(IReferenceHighlightingAdditionalReferenceProvider), LanguageNames.CSharp), Shared]
+    internal class ReferenceHighlightingAdditionalReferenceProvider : IReferenceHighlightingAdditionalReferenceProvider
     {
-        protected override async Task<ImmutableArray<Location>> GetAdditionalReferencesAsync(
+        public async Task<IEnumerable<Location>> GetAdditionalReferencesAsync(
             Document document, ISymbol symbol, CancellationToken cancellationToken)
         {
             // The FindRefs engine won't find references through 'var' for performance reasons.
             // Also, they are not needed for things like rename/sig change, and the normal find refs
-            // feature.  However, we would like the results to be highlighted to get a good experience
+            // feature.  However, we would lke the results to be highlighted to get a good experience
             // while editing (especially since highlighting may have been invoked off of 'var' in
             // the first place).
             //
             // So we look for the references through 'var' directly in this file and add them to the
             // results found by the engine.
-            var results = ArrayBuilder<Location>.GetInstance();
+            List<Location> results = null;
 
             if (symbol is INamedTypeSymbol && symbol.Name != "var")
             {
@@ -51,13 +52,18 @@ internal class CSharpDocumentHighlightsService : AbstractDocumentHighlightsServi
 
                         if (originalSymbol.Equals(boundSymbol))
                         {
+                            if (results == null)
+                            {
+                                results = new List<Location>();
+                            }
+
                             results.Add(type.GetLocation());
                         }
                     }
                 }
             }
 
-            return results.ToImmutableAndFree();
+            return results ?? SpecializedCollections.EmptyEnumerable<Location>();
         }
     }
-}
+}
\ No newline at end of file

src/EditorFeatures/Core/EditorFeatures.csproj

@@ -168,14 +168,6 @@
     <Compile Include="Implementation\Structure\BlockTagState.cs" />
     <Compile Include="Implementation\Suggestions\SuggestedActionSetComparer.cs" />
     <Compile Include="Implementation\Suggestions\SuggestedActionsSource.cs" />
-    <Compile Include="ReferenceHighlighting\NagivateToHighlightReferenceCommandHandler.cs" />
-    <Compile Include="ReferenceHighlighting\NagivateToHighlightReferenceCommandHandler.StartComparer.cs" />
-    <Compile Include="ReferenceHighlighting\ReferenceHighlightingViewTaggerProvider.cs" />
-    <Compile Include="ReferenceHighlighting\Tags\DefinitionHighlightTag.cs" />
-    <Compile Include="ReferenceHighlighting\Tags\DefinitionHighlightTagDefinition.cs" />
-    <Compile Include="ReferenceHighlighting\Tags\ReferenceHighlightTag.cs" />
-    <Compile Include="ReferenceHighlighting\Tags\WrittenReferenceHighlightTag.cs" />
-    <Compile Include="ReferenceHighlighting\Tags\WrittenReferenceHighlightTagDefinition.cs" />
     <Compile Include="SymbolSearch\IAddReferenceDatabaseWrapper.cs" />
     <Compile Include="SymbolSearch\IDatabaseFactoryService.cs" />
     <Compile Include="SymbolSearch\IDelayService.cs" />
@@ -638,6 +630,8 @@
     <Compile Include="Implementation\Peek\PeekableItemSource.cs" />
     <Compile Include="Implementation\Peek\PeekableItemSourceProvider.cs" />
     <Compile Include="Implementation\Peek\PeekHelpers.cs" />
+    <Compile Include="Implementation\ReferenceHighlighting\WrittenReferenceHighlightTag.cs" />
+    <Compile Include="Implementation\ReferenceHighlighting\WrittenReferenceHighlightTagDefinition.cs" />
     <Compile Include="Implementation\RenameTracking\IRenameTrackingLanguageHeuristicsService.cs" />
     <Compile Include="Implementation\RenameTracking\RenameTrackingCancellationCommandHandler.cs" />
     <Compile Include="Implementation\RenameTracking\RenameTrackingTagDefinition.cs" />
@@ -649,6 +643,15 @@
     <Compile Include="Implementation\Preview\PreviewConflictViewTaggerProvider.cs" />
     <Compile Include="Implementation\Preview\PreviewFactoryService.cs" />
     <Compile Include="Implementation\Preview\PreviewWarningViewTaggerProvider.cs" />
+    <Compile Include="Implementation\ReferenceHighlighting\AbstractDocumentHighlightsService.cs" />
+    <Compile Include="Implementation\ReferenceHighlighting\DefinitionHighlightTag.cs" />
+    <Compile Include="Implementation\ReferenceHighlighting\DefinitionHighlightTagDefinition.cs" />
+    <Compile Include="Implementation\ReferenceHighlighting\IDocumentHighlightsService.cs" />
+    <Compile Include="Implementation\ReferenceHighlighting\IReferenceHighlightingAdditionalReferenceProvider.cs" />
+    <Compile Include="Implementation\ReferenceHighlighting\NagivateToHighlightReferenceCommandHandler.cs" />
+    <Compile Include="Implementation\ReferenceHighlighting\NagivateToHighlightReferenceCommandHandler.StartComparer.cs" />
+    <Compile Include="Implementation\ReferenceHighlighting\ReferenceHighlightingViewTaggerProvider.cs" />
+    <Compile Include="Implementation\ReferenceHighlighting\ReferenceHighlightTag.cs" />
     <Compile Include="Implementation\RenameTracking\AbstractRenameTrackingCodeFixProvider.cs" />
     <Compile Include="Implementation\RenameTracking\RenameTrackingDiagnosticAnalyzer.cs" />
     <Compile Include="Implementation\RenameTracking\RenameTrackingTaggerProvider.cs" />

src/EditorFeatures/Core/Implementation/Preview/PreviewReferenceHighlightingTaggerProvider.cs

@@ -6,7 +6,7 @@
 using Microsoft.VisualStudio.Text.Editor;
 using Microsoft.VisualStudio.Text.Tagging;
 using Microsoft.VisualStudio.Utilities;
-using Microsoft.CodeAnalysis.Editor.ReferenceHighlighting;
+using Microsoft.CodeAnalysis.Editor.Implementation.ReferenceHighlighting;
 
 namespace Microsoft.CodeAnalysis.Editor.Implementation.Preview
 {

src/Features/Core/Portable/DocumentHighlighting/AbstractDocumentHighlightsService.cs → src/EditorFeatures/Core/Implementation/ReferenceHighlighting/AbstractDocumentHighlightsService.cs

@@ -14,47 +14,12 @@
 using Microsoft.CodeAnalysis.Text;
 using Roslyn.Utilities;
 
-namespace Microsoft.CodeAnalysis.DocumentHighlighting
+namespace Microsoft.CodeAnalysis.Editor.Implementation.ReferenceHighlighting
 {
-    internal abstract partial class AbstractDocumentHighlightsService : IDocumentHighlightsService
+    internal abstract class AbstractDocumentHighlightsService : IDocumentHighlightsService
     {
         public async Task<ImmutableArray<DocumentHighlights>> GetDocumentHighlightsAsync(
             Document document, int position, IImmutableSet<Document> documentsToSearch, CancellationToken cancellationToken)
-        {
-            var (succeeded, highlights) = await GetDocumentHighlightsInRemoteProcessAsync(
-                document, position, documentsToSearch, cancellationToken).ConfigureAwait(false);
-
-            if (succeeded)
-            {
-                return highlights;
-            }
-
-            return await GetDocumentHighlightsInCurrentProcessAsync(
-                document, position, documentsToSearch, cancellationToken).ConfigureAwait(false);
-        }
-
-        private async Task<(bool succeeded, ImmutableArray<DocumentHighlights> highlights)> GetDocumentHighlightsInRemoteProcessAsync(
-            Document document, int position, IImmutableSet<Document> documentsToSearch, CancellationToken cancellationToken)
-        {
-            using (var session = await TryGetRemoteSessionAsync(
-                document.Project.Solution, cancellationToken).ConfigureAwait(false))
-            {
-                if (session == null)
-                {
-                    return (succeeded: false, ImmutableArray<DocumentHighlights>.Empty);
-                }
-
-                var result = await session.InvokeAsync<SerializableDocumentHighlights[]>(
-                    nameof(IRemoteDocumentHighlights.GetDocumentHighlightsAsync),
-                    document.Id,
-                    position,
-                    documentsToSearch.Select(d => d.Id).ToArray()).ConfigureAwait(false);
-                return (true, SerializableDocumentHighlights.Rehydrate(result, document.Project.Solution));
-            }
-        }
-
-        private async Task<ImmutableArray<DocumentHighlights>> GetDocumentHighlightsInCurrentProcessAsync(
-            Document document, int position, IImmutableSet<Document> documentsToSearch, CancellationToken cancellationToken)
         {
             // use speculative semantic model to see whether we are on a symbol we can do HR
             var span = new TextSpan(position, 0);
@@ -76,11 +41,11 @@ internal abstract partial class AbstractDocumentHighlightsService : IDocumentHig
 
             // Get unique tags for referenced symbols
             return await GetTagsForReferencedSymbolAsync(
-                new SymbolAndProjectId(symbol, document.Project.Id), documentsToSearch,
+                new SymbolAndProjectId(symbol, document.Project.Id), documentsToSearch, 
                 solution, cancellationToken).ConfigureAwait(false);
         }
 
-        private static async Task<ISymbol> GetSymbolToSearchAsync(Document document, int position, SemanticModel semanticModel, ISymbol symbol, CancellationToken cancellationToken)
+        private async Task<ISymbol> GetSymbolToSearchAsync(Document document, int position, SemanticModel semanticModel, ISymbol symbol, CancellationToken cancellationToken)
         {
             // see whether we can use the symbol as it is
             var currentSemanticModel = await document.GetSemanticModelAsync(cancellationToken).ConfigureAwait(false);
@@ -117,7 +82,7 @@ private static async Task<ISymbol> GetSymbolToSearchAsync(Document document, int
             return ImmutableArray<DocumentHighlights>.Empty;
         }
 
-        private static bool ShouldConsiderSymbol(ISymbol symbol)
+        private bool ShouldConsiderSymbol(ISymbol symbol)
         {
             switch (symbol.Kind)
             {
@@ -167,13 +132,19 @@ private static bool ShouldConsiderSymbol(ISymbol symbol)
                 documentsToSearch, cancellationToken).ConfigureAwait(false);
         }
 
-        protected virtual Task<ImmutableArray<Location>> GetAdditionalReferencesAsync(
+        private Task<IEnumerable<Location>> GetAdditionalReferencesAsync(
             Document document, ISymbol symbol, CancellationToken cancellationToken)
         {
-            return SpecializedTasks.EmptyImmutableArray<Location>();
+            var additionalReferenceProvider = document.Project.LanguageServices.GetService<IReferenceHighlightingAdditionalReferenceProvider>();
+            if (additionalReferenceProvider != null)
+            {
+                return additionalReferenceProvider.GetAdditionalReferencesAsync(document, symbol, cancellationToken);
+            }
+
+            return Task.FromResult(SpecializedCollections.EmptyEnumerable<Location>());
         }
 
-        private static async Task<ImmutableArray<DocumentHighlights>> CreateSpansAsync(
+        private async Task<ImmutableArray<DocumentHighlights>> CreateSpansAsync(
             Solution solution,
             ISymbol symbol,
             IEnumerable<ReferencedSymbol> references,
@@ -281,7 +252,7 @@ private static bool ShouldIncludeDefinition(ISymbol symbol)
             return true;
         }
 
-        private static async Task AddLocationSpan(Location location, Solution solution, HashSet<DocumentSpan> spanSet, MultiDictionary<Document, HighlightSpan> tagList, HighlightSpanKind kind, CancellationToken cancellationToken)
+        private async Task AddLocationSpan(Location location, Solution solution, HashSet<DocumentSpan> spanSet, MultiDictionary<Document, HighlightSpan> tagList, HighlightSpanKind kind, CancellationToken cancellationToken)
         {
             var span = await GetLocationSpanAsync(solution, location, cancellationToken).ConfigureAwait(false);
             if (span != null && !spanSet.Contains(span.Value))
@@ -291,7 +262,7 @@ private static async Task AddLocationSpan(Location location, Solution solution,
             }
         }
 
-        private static async Task<DocumentSpan?> GetLocationSpanAsync(
+        private async Task<DocumentSpan?> GetLocationSpanAsync(
             Solution solution, Location location, CancellationToken cancellationToken)
         {
             try

src/EditorFeatures/Core/ReferenceHighlighting/Tags/DefinitionHighlightTag.cs → src/EditorFeatures/Core/Implementation/ReferenceHighlighting/DefinitionHighlightTag.cs

@@ -2,7 +2,7 @@
 
 using Microsoft.CodeAnalysis.Editor.Shared.Tagging;
 
-namespace Microsoft.CodeAnalysis.Editor.ReferenceHighlighting
+namespace Microsoft.CodeAnalysis.Editor.Implementation.ReferenceHighlighting
 {
     internal class DefinitionHighlightTag : NavigableHighlightTag
     {

src/EditorFeatures/Core/ReferenceHighlighting/Tags/DefinitionHighlightTagDefinition.cs → src/EditorFeatures/Core/Implementation/ReferenceHighlighting/DefinitionHighlightTagDefinition.cs

@@ -5,7 +5,7 @@
 using Microsoft.VisualStudio.Text.Classification;
 using Microsoft.VisualStudio.Utilities;
 
-namespace Microsoft.CodeAnalysis.Editor.ReferenceHighlighting
+namespace Microsoft.CodeAnalysis.Editor.Implementation.ReferenceHighlighting
 {
     [Export(typeof(EditorFormatDefinition))]
     [Name(DefinitionHighlightTag.TagId)]

src/Features/Core/Portable/DocumentHighlighting/IDocumentHighlightsService.cs → src/EditorFeatures/Core/Implementation/ReferenceHighlighting/IDocumentHighlightsService.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.Collections.Generic;
 using System.Collections.Immutable;
 using System.Threading;
 using System.Threading.Tasks;
 using Microsoft.CodeAnalysis.Host;
 using Microsoft.CodeAnalysis.Text;
 
-namespace Microsoft.CodeAnalysis.DocumentHighlighting
+namespace Microsoft.CodeAnalysis.Editor
 {
     internal enum HighlightSpanKind
     {

src/EditorFeatures/Core/Implementation/ReferenceHighlighting/IReferenceHighlightingAdditionalReferenceProvider.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.Collections.Generic;
+using System.Threading;
+using System.Threading.Tasks;
+using Microsoft.CodeAnalysis.Host;
+
+namespace Microsoft.CodeAnalysis.Editor.Implementation.ReferenceHighlighting
+{
+    internal interface IReferenceHighlightingAdditionalReferenceProvider : ILanguageService
+    {
+        Task<IEnumerable<Location>> GetAdditionalReferencesAsync(Document document, ISymbol symbol, CancellationToken cancellationToken);
+    }
+}

src/EditorFeatures/Core/ReferenceHighlighting/NagivateToHighlightReferenceCommandHandler.StartComparer.cs → src/EditorFeatures/Core/Implementation/ReferenceHighlighting/NagivateToHighlightReferenceCommandHandler.StartComparer.cs

@@ -3,7 +3,7 @@
 using System.Collections.Generic;
 using Microsoft.VisualStudio.Text;
 
-namespace Microsoft.CodeAnalysis.Editor.ReferenceHighlighting
+namespace Microsoft.CodeAnalysis.Editor.Implementation.ReferenceHighlighting
 {
     internal partial class NavigateToHighlightReferenceCommandHandler
     {

src/EditorFeatures/Core/ReferenceHighlighting/NagivateToHighlightReferenceCommandHandler.cs → src/EditorFeatures/Core/Implementation/ReferenceHighlighting/NagivateToHighlightReferenceCommandHandler.cs

@@ -14,7 +14,7 @@
 using Microsoft.VisualStudio.Text.Tagging;
 using Roslyn.Utilities;
 
-namespace Microsoft.CodeAnalysis.Editor.ReferenceHighlighting
+namespace Microsoft.CodeAnalysis.Editor.Implementation.ReferenceHighlighting
 {
     [ExportCommandHandler(PredefinedCommandHandlerNames.NavigateToHighlightedReference,
        ContentTypeNames.RoslynContentType)]

src/EditorFeatures/Core/ReferenceHighlighting/Tags/ReferenceHighlightTag.cs → src/EditorFeatures/Core/Implementation/ReferenceHighlighting/ReferenceHighlightTag.cs

@@ -2,7 +2,7 @@
 
 using Microsoft.CodeAnalysis.Editor.Shared.Tagging;
 
-namespace Microsoft.CodeAnalysis.Editor.ReferenceHighlighting
+namespace Microsoft.CodeAnalysis.Editor.Implementation.ReferenceHighlighting
 {
     internal class ReferenceHighlightTag : NavigableHighlightTag
     {

src/EditorFeatures/Core/ReferenceHighlighting/ReferenceHighlightingViewTaggerProvider.cs → src/EditorFeatures/Core/Implementation/ReferenceHighlighting/ReferenceHighlightingViewTaggerProvider.cs

@@ -6,7 +6,6 @@
 using System.ComponentModel.Composition;
 using System.Linq;
 using System.Threading.Tasks;
-using Microsoft.CodeAnalysis.DocumentHighlighting;
 using Microsoft.CodeAnalysis.Editor.Shared.Options;
 using Microsoft.CodeAnalysis.Editor.Shared.Tagging;
 using Microsoft.CodeAnalysis.Editor.Tagging;
@@ -22,7 +21,7 @@
 using Microsoft.VisualStudio.Utilities;
 using Roslyn.Utilities;
 
-namespace Microsoft.CodeAnalysis.Editor.ReferenceHighlighting
+namespace Microsoft.CodeAnalysis.Editor.Implementation.ReferenceHighlighting
 {
     [Export(typeof(IViewTaggerProvider))]
     [ContentType(ContentTypeNames.RoslynContentType)]

src/EditorFeatures/Core/ReferenceHighlighting/Tags/WrittenReferenceHighlightTag.cs → src/EditorFeatures/Core/Implementation/ReferenceHighlighting/WrittenReferenceHighlightTag.cs

@@ -2,7 +2,7 @@
 
 using Microsoft.CodeAnalysis.Editor.Shared.Tagging;
 
-namespace Microsoft.CodeAnalysis.Editor.ReferenceHighlighting
+namespace Microsoft.CodeAnalysis.Editor.Implementation.ReferenceHighlighting
 {
     internal class WrittenReferenceHighlightTag : NavigableHighlightTag
     {

src/EditorFeatures/Core/ReferenceHighlighting/Tags/WrittenReferenceHighlightTagDefinition.cs → src/EditorFeatures/Core/Implementation/ReferenceHighlighting/WrittenReferenceHighlightTagDefinition.cs

@@ -5,7 +5,7 @@
 using Microsoft.VisualStudio.Text.Classification;
 using Microsoft.VisualStudio.Utilities;
 
-namespace Microsoft.CodeAnalysis.Editor.ReferenceHighlighting
+namespace Microsoft.CodeAnalysis.Editor.Implementation.ReferenceHighlighting
 {
     [Export(typeof(EditorFormatDefinition))]
     [Name(WrittenReferenceHighlightTag.TagId)]

src/EditorFeatures/Test2/ReferenceHighlighting/AbstractReferenceHighlightingTests.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 System.Threading
-Imports Microsoft.CodeAnalysis.DocumentHighlighting
-Imports Microsoft.CodeAnalysis.Editor.ReferenceHighlighting
+Imports Microsoft.CodeAnalysis.Editor.Implementation.ReferenceHighlighting
 Imports Microsoft.CodeAnalysis.Editor.Shared.Extensions
 Imports Microsoft.CodeAnalysis.Editor.Shared.Options
 Imports Microsoft.CodeAnalysis.Editor.Shared.Tagging
@@ -17,17 +16,9 @@ Namespace Microsoft.CodeAnalysis.Editor.UnitTests.ReferenceHighlighting
 
     Public MustInherit Class AbstractReferenceHighlightingTests
         Protected Async Function VerifyHighlightsAsync(test As XElement, Optional optionIsEnabled As Boolean = True) As Tasks.Task
-            Await VerifyHighlightsAsync(test, optionIsEnabled, outOfProcess:=False)
-            Await VerifyHighlightsAsync(test, optionIsEnabled, outOfProcess:=True)
-        End Function
-
-        Private Async Function VerifyHighlightsAsync(test As XElement, optionIsEnabled As Boolean, outOfProcess As Boolean) As Tasks.Task
             Using workspace = TestWorkspace.Create(test)
                 WpfTestCase.RequireWpfFact($"{NameOf(AbstractReferenceHighlightingTests)}.VerifyHighlightsAsync creates asynchronous taggers")
 
-                workspace.Options = workspace.Options.WithChangedOption(
-                    DocumentHighlightingOptions.OutOfProcessAllowed, outOfProcess)
-
                 Dim tagProducer = New ReferenceHighlightingViewTaggerProvider(
                     workspace.GetService(Of IForegroundNotificationService),
                     workspace.GetService(Of ISemanticChangeNotificationService),

src/EditorFeatures/VisualBasic/BasicEditorFeatures.vbproj

@@ -129,6 +129,7 @@
     <Compile Include="Highlighting\KeywordHighlighters\XmlEmbeddedExpressionHighlighter.vb" />
     <Compile Include="Highlighting\KeywordHighlighters\XmlProcessingInstructionHighlighter.vb" />
     <Compile Include="Highlighting\KeywordHighlightingHelpers.vb" />
+    <Compile Include="HighlightReferences\VisualBasicDocumentHighlightsService.vb" />
     <Compile Include="ImplementAbstractClass\ImplementAbstractClassCommandHandler.vb" />
     <Compile Include="ImplementInterface\ImplementInterfaceCommandHandler.vb" />
     <Compile Include="InlineRename\VisualBasicEditorInlineRenameService.vb" />
@@ -154,6 +155,7 @@
     <Compile Include="NavigationBar\GenerateMethodItem.vb" />
     <Compile Include="NavigationBar\VisualBasicNavigationBarItemService.vb" />
     <Compile Include="QuickInfo\SemanticQuickInfoProvider.vb" />
+    <Compile Include="ReferenceHighlighting\ReferenceHighlightingAdditionalReferenceProvider.vb" />
     <Compile Include="RenameTracking\BasicRenameTrackingLanguageHeuristicsService.vb" />
     <Compile Include="RenameTracking\RenameTrackingCodeFixProvider.vb" />
     <Compile Include="TextStructureNavigation\TextStructureNavigatorProvider.vb" />

src/Features/VisualBasic/Portable/DocumentHighlighting/VisualBasicDocumentHighlightsService.vb → src/EditorFeatures/VisualBasic/HighlightReferences/VisualBasicDocumentHighlightsService.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 System.Composition
-Imports Microsoft.CodeAnalysis.DocumentHighlighting
+Imports Microsoft.CodeAnalysis.Editor.Implementation.ReferenceHighlighting
 Imports Microsoft.CodeAnalysis.Host.Mef
 
-Namespace Microsoft.CodeAnalysis.VisualBasic.DocumentHighlighting
+Namespace Microsoft.CodeAnalysis.Editor.VisualBasic.HighlightReferences
     <ExportLanguageService(GetType(IDocumentHighlightsService), LanguageNames.VisualBasic), [Shared]>
     Friend Class VisualBasicDocumentHighlightsService
         Inherits AbstractDocumentHighlightsService
 
     End Class
-End Namespace
+End Namespace
\ No newline at end of file

src/EditorFeatures/VisualBasic/ReferenceHighlighting/ReferenceHighlightingAdditionalReferenceProvider.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 System.Composition
+Imports System.Threading
+Imports System.Threading.Tasks
+Imports Microsoft.CodeAnalysis.Editor.Implementation.ReferenceHighlighting
+Imports Microsoft.CodeAnalysis.Host.Mef
+
+Namespace Microsoft.CodeAnalysis.Editor.VisualBasic.ReferenceHighlighting
+    <ExportLanguageService(GetType(IReferenceHighlightingAdditionalReferenceProvider), LanguageNames.VisualBasic), [Shared]>
+    Friend Class ReferenceHighlightingAdditionalReferenceProvider
+        Implements IReferenceHighlightingAdditionalReferenceProvider
+
+        Public Function GetAdditionalReferencesAsync(document As Document, symbol As ISymbol, cancellationToken As CancellationToken) As Task(Of IEnumerable(Of Location)) Implements IReferenceHighlightingAdditionalReferenceProvider.GetAdditionalReferencesAsync
+            Return SpecializedTasks.EmptyEnumerable(Of Location)()
+        End Function
+    End Class
+End Namespace

src/Features/CSharp/Portable/CSharpFeatures.csproj

@@ -81,7 +81,6 @@
     </Compile>
     <Compile Include="DesignerAttributes\CSharpDesignerAttributeService.cs" />
     <Compile Include="Completion\CompletionProviders\DeclarationNameCompletionProvider.cs" />
-    <Compile Include="DocumentHighlighting\CSharpDocumentHighlightsService.cs" />
     <Compile Include="ImplementAbstractClass\CSharpImplementAbstractClassCodeFixProvider.cs" />
     <Compile Include="ImplementInterface\CSharpImplementInterfaceCodeFixProvider.cs" />
     <Compile Include="InitializeParameter\CSharpAddParameterCheckCodeRefactoringProvider.cs" />

src/Features/Core/Portable/DocumentHighlighting/AbstractDocumentHighlightsService_Remote.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.Threading;
-using System.Threading.Tasks;
-using Microsoft.CodeAnalysis.Remote;
-
-namespace Microsoft.CodeAnalysis.DocumentHighlighting
-{
-    internal abstract partial class AbstractDocumentHighlightsService : IDocumentHighlightsService
-    {
-        private static async Task<RemoteHostClient.Session> TryGetRemoteSessionAsync(
-            Solution solution, CancellationToken cancellationToken)
-        {
-            var outOfProcessAllowed = solution.Workspace.Options.GetOption(DocumentHighlightingOptions.OutOfProcessAllowed);
-            if (!outOfProcessAllowed)
-            {
-                return null;
-            }
-
-            var client = await solution.Workspace.TryGetRemoteHostClientAsync(cancellationToken).ConfigureAwait(false);
-            if (client == null)
-            {
-                return null;
-            }
-
-            return await client.TryCreateCodeAnalysisServiceSessionAsync(
-                solution, cancellationToken).ConfigureAwait(false);
-        }
-    }
-}
\ No newline at end of file

src/Features/Core/Portable/DocumentHighlighting/DocumentHighlightingOptions.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 Microsoft.CodeAnalysis.Options;
-
-namespace Microsoft.CodeAnalysis.DocumentHighlighting
-{
-    internal static class DocumentHighlightingOptions
-    {
-        private const string LocalRegistryPath = @"Roslyn\Features\DocumentHighlighting\";
-
-        public static readonly Option<bool> OutOfProcessAllowed = new Option<bool>(
-            nameof(DocumentHighlightingOptions), nameof(OutOfProcessAllowed), defaultValue: false,
-            storageLocations: new LocalUserProfileStorageLocation(LocalRegistryPath + nameof(OutOfProcessAllowed)));
-    }
-}
\ No newline at end of file

src/Features/Core/Portable/DocumentHighlighting/IRemoteDocumentHighlights.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.Collections.Immutable;
-using System.Threading.Tasks;
-using Microsoft.CodeAnalysis.Text;
-
-namespace Microsoft.CodeAnalysis.DocumentHighlighting
-{
-    internal interface IRemoteDocumentHighlights
-    {
-        Task<SerializableDocumentHighlights[]> GetDocumentHighlightsAsync(
-            DocumentId documentId, int position, DocumentId[] documentIdsToSearch);
-    }
-
-    internal struct SerializableDocumentHighlights
-    {
-        public DocumentId DocumentId;
-        public SerializableHighlightSpan[] HighlightSpans;
-
-        public static ImmutableArray<DocumentHighlights> Rehydrate(SerializableDocumentHighlights[] array, Solution solution)
-        {
-            var result = ArrayBuilder<DocumentHighlights>.GetInstance(array.Length);
-            foreach (var dehydrated in array)
-            {
-                result.Push(dehydrated.Rehydrate(solution));
-            }
-
-            return result.ToImmutableAndFree();
-        }
-
-        private DocumentHighlights Rehydrate(Solution solution)
-            => new DocumentHighlights(solution.GetDocument(DocumentId), SerializableHighlightSpan.Rehydrate(HighlightSpans));
-
-        public static SerializableDocumentHighlights[] Dehydrate(ImmutableArray<DocumentHighlights> array)
-        {
-            var result = new SerializableDocumentHighlights[array.Length];
-            var index = 0;
-            foreach (var highlights in array)
-            {
-                result[index] = Dehydrate(highlights);
-                index++;
-            }
-
-            return result;
-        }
-
-        private static SerializableDocumentHighlights Dehydrate(DocumentHighlights highlights)
-            => new SerializableDocumentHighlights
-            {
-                DocumentId = highlights.Document.Id,
-                HighlightSpans = SerializableHighlightSpan.Dehydrate(highlights.HighlightSpans)
-            };
-    }
-
-    internal struct SerializableHighlightSpan
-    {
-        public TextSpan TextSpan;
-        public HighlightSpanKind Kind;
-
-        internal static SerializableHighlightSpan[] Dehydrate(ImmutableArray<HighlightSpan> array)
-        {
-            var result = new SerializableHighlightSpan[array.Length];
-            var index = 0;
-            foreach (var span in array)
-            {
-                result[index] = Dehydrate(span);
-                index++;
-            }
-
-            return result;
-        }
-
-        private static SerializableHighlightSpan Dehydrate(HighlightSpan span)
-            => new SerializableHighlightSpan
-            {
-                Kind = span.Kind,
-                TextSpan = span.TextSpan
-            };
-
-        internal static ImmutableArray<HighlightSpan> Rehydrate(SerializableHighlightSpan[] array)
-        {
-            var result = ArrayBuilder<HighlightSpan>.GetInstance(array.Length);
-            foreach (var dehydrated in array)
-            {
-                result.Push(dehydrated.Rehydrate());
-            }
-
-            return result.ToImmutableAndFree();
-        }
-
-        private HighlightSpan Rehydrate()
-            => new HighlightSpan(TextSpan, Kind);
-    }
-}
\ No newline at end of file

src/Features/Core/Portable/Features.csproj

@@ -132,7 +132,6 @@
     <Compile Include="Diagnostics\DiagnosticArguments.cs" />
     <Compile Include="Diagnostics\DiagnosticResultSerializer.cs" />
     <Compile Include="Diagnostics\SymbolAnalysisContextExtensions.cs" />
-    <Compile Include="DocumentHighlighting\DocumentHighlightingOptions.cs" />
     <Compile Include="EncapsulateField\EncapsulateFieldRefactoringProvider.cs" />
     <Compile Include="ExtractInterface\ExtractInterfaceCodeRefactoringProvider.cs" />
     <Compile Include="CodeFixes\FixAllOccurrences\FixSomeCodeAction.cs" />
@@ -158,10 +157,6 @@
     <Compile Include="GenerateFromMembers\SelectedMemberInfo.cs" />
     <Compile Include="ImplementType\ImplementTypeOptions.cs" />
     <Compile Include="ImplementType\ImplementTypeOptionsProvider.cs" />
-    <Compile Include="DocumentHighlighting\AbstractDocumentHighlightsService.cs" />
-    <Compile Include="DocumentHighlighting\AbstractDocumentHighlightsService_Remote.cs" />
-    <Compile Include="DocumentHighlighting\IDocumentHighlightsService.cs" />
-    <Compile Include="DocumentHighlighting\IRemoteDocumentHighlights.cs" />
     <Compile Include="RemoveUnnecessaryImports\AbstractRemoveUnnecessaryImportsCodeFixProvider.cs" />
     <Compile Include="RemoveUnnecessaryImports\IUnnecessaryImportsService.cs" />
     <Compile Include="NavigateTo\AbstractNavigateToSearchService.SearchResult.cs" />

src/Features/VisualBasic/Portable/BasicFeatures.vbproj

@@ -66,7 +66,6 @@
       <Link>InternalUtilities\LambdaUtilities.vb</Link>
     </Compile>
     <Compile Include="AddPackage\VisualBasicAddSpecificPackageCodeFixProvider.vb" />
-    <Compile Include="DocumentHighlighting\VisualBasicDocumentHighlightsService.vb" />
     <Compile Include="InitializeParameter\InitializeParameterHelpers.vb" />
     <Compile Include="InitializeParameter\VisualBasicAddParameterCheckCodeRefactoringProvider.vb" />
     <Compile Include="ChangeSignature\ChangeSignatureFormattingRule.vb" />

src/VisualStudio/Core/Next/FindReferences/Contexts/AbstractTableDataSourceFindUsagesContext.cs

@@ -7,7 +7,7 @@
 using System.Threading;
 using System.Threading.Tasks;
 using Microsoft.CodeAnalysis;
-using Microsoft.CodeAnalysis.DocumentHighlighting;
+using Microsoft.CodeAnalysis.Editor;
 using Microsoft.CodeAnalysis.Editor.FindUsages;
 using Microsoft.CodeAnalysis.FindUsages;
 using Microsoft.CodeAnalysis.Text;

src/VisualStudio/Core/Next/FindReferences/Contexts/WithReferencesFindUsagesContext.cs

@@ -8,7 +8,7 @@
 using System.Threading.Tasks;
 using Microsoft.CodeAnalysis;
 using Microsoft.CodeAnalysis.Completion;
-using Microsoft.CodeAnalysis.DocumentHighlighting;
+using Microsoft.CodeAnalysis.Editor;
 using Microsoft.CodeAnalysis.FindUsages;
 using Microsoft.VisualStudio.Shell.FindAllReferences;
 using Roslyn.Utilities;

src/VisualStudio/Core/Next/FindReferences/Contexts/WithoutReferencesFindUsagesContext.cs

@@ -3,7 +3,7 @@
 using System;
 using System.Threading.Tasks;
 using Microsoft.CodeAnalysis;
-using Microsoft.CodeAnalysis.DocumentHighlighting;
+using Microsoft.CodeAnalysis.Editor;
 using Microsoft.CodeAnalysis.FindUsages;
 using Microsoft.VisualStudio.Shell.FindAllReferences;
 using Roslyn.Utilities;

src/VisualStudio/Core/Next/FindReferences/Entries/DocumentSpanEntry.cs

@@ -7,11 +7,10 @@
 using System.Windows.Media;
 using Microsoft.CodeAnalysis;
 using Microsoft.CodeAnalysis.Classification;
-using Microsoft.CodeAnalysis.DocumentHighlighting;
 using Microsoft.CodeAnalysis.Editor;
 using Microsoft.CodeAnalysis.Editor.FindUsages;
 using Microsoft.CodeAnalysis.Editor.Implementation.IntelliSense.QuickInfo;
-using Microsoft.CodeAnalysis.Editor.ReferenceHighlighting;
+using Microsoft.CodeAnalysis.Editor.Implementation.ReferenceHighlighting;
 using Microsoft.CodeAnalysis.Editor.Shared.Extensions;
 using Microsoft.CodeAnalysis.Editor.Shared.Preview;
 using Microsoft.CodeAnalysis.FindUsages;
@@ -19,6 +18,7 @@
 using Microsoft.CodeAnalysis.Text.Shared.Extensions;
 using Microsoft.VisualStudio.LanguageServices.Implementation.Extensions;
 using Microsoft.VisualStudio.PlatformUI;
+using Microsoft.VisualStudio.Shell.TableControl;
 using Microsoft.VisualStudio.Text;
 using Microsoft.VisualStudio.Text.Editor;
 

src/VisualStudio/IntegrationTest/IntegrationTests/CSharp/CSharpReferenceHighlighting.cs

@@ -3,10 +3,11 @@
 using System.Collections.Generic;
 using System.Collections.Immutable;
 using Microsoft.CodeAnalysis;
-using Microsoft.CodeAnalysis.Editor.ReferenceHighlighting;
+using Microsoft.CodeAnalysis.Editor.Implementation.ReferenceHighlighting;
 using Microsoft.CodeAnalysis.Shared.TestHooks;
 using Microsoft.CodeAnalysis.Text;
 using Microsoft.VisualStudio.IntegrationTest.Utilities;
+using Microsoft.VisualStudio.IntegrationTest.Utilities.Input;
 using Roslyn.Test.Utilities;
 using Xunit;
 

src/VisualStudio/IntegrationTest/IntegrationTests/VisualBasic/BasicReferenceHighlighting.cs

@@ -3,10 +3,11 @@
 using System.Collections.Generic;
 using System.Collections.Immutable;
 using Microsoft.CodeAnalysis;
-using Microsoft.CodeAnalysis.Editor.ReferenceHighlighting;
+using Microsoft.CodeAnalysis.Editor.Implementation.ReferenceHighlighting;
 using Microsoft.CodeAnalysis.Shared.TestHooks;
 using Microsoft.CodeAnalysis.Text;
 using Microsoft.VisualStudio.IntegrationTest.Utilities;
+using Microsoft.VisualStudio.IntegrationTest.Utilities.Input;
 using Roslyn.Test.Utilities;
 using Xunit;
 

src/VisualStudio/IntegrationTest/TestUtilities/WellKnownTagNames.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 Microsoft.CodeAnalysis.Editor.ReferenceHighlighting;
+using Microsoft.CodeAnalysis.Editor.Implementation.ReferenceHighlighting;
 
 namespace Microsoft.VisualStudio.IntegrationTest.Utilities
 {

src/Workspaces/Remote/ServiceHub/ServiceHub.csproj

@@ -73,7 +73,6 @@
     </Compile>
     <Compile Include="Services\CodeAnalysisService_CodeLens.cs" />
     <Compile Include="Services\CodeAnalysisService_DesignerAttributes.cs" />
-    <Compile Include="Services\CodeAnalysisService_DocumentHighlights.cs" />
     <Compile Include="Services\CodeAnalysisService_TodoComments.cs" />
     <Compile Include="Services\CodeAnalysisService_SymbolFinder.cs" />
     <Compile Include="Services\RemoteSymbolSearchUpdateEngine.cs" />

src/Workspaces/Remote/ServiceHub/Services/CodeAnalysisService_DocumentHighlights.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.Collections.Immutable;
-using System.Linq;
-using System.Threading.Tasks;
-using Microsoft.CodeAnalysis.DocumentHighlighting;
-using Microsoft.CodeAnalysis.Shared.Extensions;
-
-namespace Microsoft.CodeAnalysis.Remote
-{
-    // root level service for all Roslyn services
-    internal partial class CodeAnalysisService : IRemoteDocumentHighlights
-    {
-        public async Task<SerializableDocumentHighlights[]> GetDocumentHighlightsAsync(
-            DocumentId documentId, int position, DocumentId[] documentIdsToSearch)
-        {
-            var solution = await GetSolutionAsync().ConfigureAwait(false);
-            var document = solution.GetDocument(documentId);
-            var documentsToSearch = ImmutableHashSet.CreateRange(documentIdsToSearch.Select(solution.GetDocument));
-
-            var service = document.GetLanguageService<IDocumentHighlightsService>();
-            var result = await service.GetDocumentHighlightsAsync(
-                document, position, documentsToSearch, CancellationToken).ConfigureAwait(false);
-
-            return SerializableDocumentHighlights.Dehydrate(result);
-        }
-    }
-}
\ No newline at end of file