Place ITextBufferCloneService in ITextBuffer.Properties instead of separate...

Place ITextBufferCloneService in ITextBuffer.Properties instead of separate tracking in SnapshotSourceText

src/EditorFeatures/Core/Implementation/Workspaces/EditorTextFactoryService.cs

@@ -13,18 +13,20 @@
 
 namespace Microsoft.CodeAnalysis.Editor.Implementation.Workspaces
 {
+    [ExportWorkspaceService(typeof(ITextFactoryService), ServiceLayer.Editor), Shared]
     internal class EditorTextFactoryService : ITextFactoryService
     {
-        private readonly Workspace _workspace;
+        private readonly ITextBufferCloneService _textBufferCloneService;
         private readonly ITextBufferFactoryService _textBufferFactory;
         private readonly IContentType _unknownContentType;
 
+        [ImportingConstructor]
         public EditorTextFactoryService(
-            Workspace workspace,
+            ITextBufferCloneService textBufferCloneService,
             ITextBufferFactoryService textBufferFactoryService,
             IContentTypeRegistryService contentTypeRegistryService)
         {
-            _workspace = workspace;
+            _textBufferCloneService = textBufferCloneService;
             _textBufferFactory = textBufferFactoryService;
             _unknownContentType = contentTypeRegistryService.UnknownContentType;
         }
@@ -69,7 +71,7 @@ public SourceText CreateText(TextReader reader, Encoding encoding, CancellationT
             var buffer = CreateTextBuffer(reader, cancellationToken);
 
             // use the given encoding as it is.
-            return buffer.CurrentSnapshot.AsRoslynText(_workspace, encoding);
+            return buffer.CurrentSnapshot.AsRoslynText(_textBufferCloneService, encoding);
         }
 
         private ITextBuffer CreateTextBuffer(TextReader reader, CancellationToken cancellationToken = default)
@@ -85,31 +87,7 @@ private SourceText CreateTextInternal(Stream stream, Encoding encoding, Cancella
             using (var reader = new StreamReader(stream, encoding, detectEncodingFromByteOrderMarks: true, bufferSize: 1024, leaveOpen: true))
             {
                 var buffer = CreateTextBuffer(reader, cancellationToken);
-                return buffer.CurrentSnapshot.AsRoslynText(_workspace, reader.CurrentEncoding ?? Encoding.UTF8);
-            }
-        }
-
-        [ExportWorkspaceServiceFactory(typeof(ITextFactoryService), ServiceLayer.Editor), Shared]
-        private sealed class Factory : IWorkspaceServiceFactory
-        {
-            private readonly ITextBufferFactoryService _textBufferFactoryService;
-            private readonly IContentTypeRegistryService _contentTypeRegistryService;
-
-            [ImportingConstructor]
-            public Factory(
-                ITextBufferFactoryService textBufferFactoryService,
-                IContentTypeRegistryService contentTypeRegistryService)
-            {
-                _textBufferFactoryService = textBufferFactoryService;
-                _contentTypeRegistryService = contentTypeRegistryService;
-            }
-
-            public IWorkspaceService CreateService(HostWorkspaceServices workspaceServices)
-            {
-                return new EditorTextFactoryService(
-                    workspaceServices.Workspace,
-                    _textBufferFactoryService,
-                    _contentTypeRegistryService);
+                return buffer.CurrentSnapshot.AsRoslynText(_textBufferCloneService, reader.CurrentEncoding ?? Encoding.UTF8);
             }
         }
     }

src/EditorFeatures/Test/Extensions/SourceTextContainerExtensionsTests.cs

@@ -33,7 +33,7 @@ public void GetBufferTextFromTextContainerDoesNotThrow()
             bufferMock.SetupGet(x => x.CurrentSnapshot).Returns(textSnapshotMock.Object);
             bufferMock.SetupGet(x => x.Properties).Returns(new VisualStudio.Utilities.PropertyCollection());
 
-            var textContainer = Text.Extensions.TextBufferContainer.From(workspace: null, bufferMock.Object);
+            var textContainer = Text.Extensions.TextBufferContainer.From(bufferMock.Object);
 
             Text.Extensions.GetTextBuffer(textContainer);
         }

src/EditorFeatures/Test/Workspaces/TextFactoryTests.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.IO;
 using System.Linq;
 using System.Text;
 using System.Threading.Tasks;
 using Microsoft.CodeAnalysis.Editor.Implementation.Workspaces;
 using Microsoft.CodeAnalysis.Host;
+using Microsoft.CodeAnalysis.Text;
 using Microsoft.VisualStudio.Text;
 using Microsoft.VisualStudio.Utilities;
 using Moq;
@@ -21,108 +23,86 @@ public class TextFactoryTests
         [Fact, WorkItem(1038018, "http://vstfdevdiv:8080/DevDiv2/DevDiv/_workitems/edit/1038018"), WorkItem(1041792, "http://vstfdevdiv:8080/DevDiv2/DevDiv/_workitems/edit/1041792")]
         public void TestCreateTextFallsBackToSystemDefaultEncoding()
         {
-            using (var workspace = new TestWorkspace())
-            {
-                TestCreateTextInferredEncoding(
-                    workspace,
-                    _nonUTF8StringBytes,
-                    defaultEncoding: null,
-                    expectedEncoding: Encoding.Default);
-            }
+            TestCreateTextInferredEncoding(
+                _nonUTF8StringBytes,
+                defaultEncoding: null,
+                expectedEncoding: Encoding.Default);
         }
 
         [Fact, WorkItem(1038018, "http://vstfdevdiv:8080/DevDiv2/DevDiv/_workitems/edit/1038018")]
         public void TestCreateTextFallsBackToUTF8Encoding()
         {
-            using (var workspace = new TestWorkspace())
-            {
-                TestCreateTextInferredEncoding(
-                    workspace,
-                    new ASCIIEncoding().GetBytes("Test"),
-                    defaultEncoding: null,
-                    expectedEncoding: new UTF8Encoding(encoderShouldEmitUTF8Identifier: false, throwOnInvalidBytes: true));
-            }
+            TestCreateTextInferredEncoding(
+                new ASCIIEncoding().GetBytes("Test"),
+                defaultEncoding: null,
+                expectedEncoding: new UTF8Encoding(encoderShouldEmitUTF8Identifier: false, throwOnInvalidBytes: true));
         }
 
         [Fact, WorkItem(1038018, "http://vstfdevdiv:8080/DevDiv2/DevDiv/_workitems/edit/1038018")]
         public void TestCreateTextFallsBackToProvidedDefaultEncoding()
         {
-            using (var workspace = new TestWorkspace())
-            {
-                TestCreateTextInferredEncoding(
-                    workspace,
-                    new UTF8Encoding(encoderShouldEmitUTF8Identifier: false, throwOnInvalidBytes: true).GetBytes("Test"),
-                    defaultEncoding: Encoding.GetEncoding(1254),
-                    expectedEncoding: Encoding.GetEncoding(1254));
-            }
+            TestCreateTextInferredEncoding(
+                new UTF8Encoding(encoderShouldEmitUTF8Identifier: false, throwOnInvalidBytes: true).GetBytes("Test"),
+                defaultEncoding: Encoding.GetEncoding(1254),
+                expectedEncoding: Encoding.GetEncoding(1254));
         }
 
         [Fact, WorkItem(1038018, "http://vstfdevdiv:8080/DevDiv2/DevDiv/_workitems/edit/1038018")]
         public void TestCreateTextUsesByteOrderMarkIfPresent()
         {
-            using (var workspace = new TestWorkspace())
-            {
-                TestCreateTextInferredEncoding(
-                    workspace,
-                    Encoding.UTF8.GetPreamble().Concat(new UTF8Encoding(encoderShouldEmitUTF8Identifier: false, throwOnInvalidBytes: true).GetBytes("Test")).ToArray(),
-                    defaultEncoding: Encoding.GetEncoding(1254),
-                    expectedEncoding: Encoding.UTF8);
-            }
+            TestCreateTextInferredEncoding(
+                Encoding.UTF8.GetPreamble().Concat(new UTF8Encoding(encoderShouldEmitUTF8Identifier: false, throwOnInvalidBytes: true).GetBytes("Test")).ToArray(),
+                defaultEncoding: Encoding.GetEncoding(1254),
+                expectedEncoding: Encoding.UTF8);
         }
 
         [Fact]
         public async Task TestCreateFromTemporaryStorage()
         {
-            using (var workspace = new TestWorkspace())
-            {
-                var textFactory = CreateMockTextFactoryService(workspace);
-                var temporaryStorageService = new TemporaryStorageServiceFactory.TemporaryStorageService(textFactory);
+            var textFactory = CreateMockTextFactoryService();
+            var temporaryStorageService = new TemporaryStorageServiceFactory.TemporaryStorageService(textFactory);
 
-                var text = Text.SourceText.From("Hello, World!");
+            var text = Text.SourceText.From("Hello, World!");
 
-                // Create a temporary storage location
-                using (var temporaryStorage = temporaryStorageService.CreateTemporaryTextStorage(System.Threading.CancellationToken.None))
-                {
-                    // Write text into it
-                    await temporaryStorage.WriteTextAsync(text);
+            // Create a temporary storage location
+            using (var temporaryStorage = temporaryStorageService.CreateTemporaryTextStorage(System.Threading.CancellationToken.None))
+            {
+                // Write text into it
+                await temporaryStorage.WriteTextAsync(text);
 
-                    // Read text back from it
-                    var text2 = await temporaryStorage.ReadTextAsync();
+                // Read text back from it
+                var text2 = await temporaryStorage.ReadTextAsync();
 
-                    Assert.NotSame(text, text2);
-                    Assert.Equal(text.ToString(), text2.ToString());
-                    Assert.Equal(text2.Encoding, null);
-                }
+                Assert.NotSame(text, text2);
+                Assert.Equal(text.ToString(), text2.ToString());
+                Assert.Equal(text2.Encoding, null);
             }
         }
 
         [Fact]
         public async Task TestCreateFromTemporaryStorageWithEncoding()
         {
-            using (var workspace = new TestWorkspace())
-            {
-                var textFactory = CreateMockTextFactoryService(workspace);
-                var temporaryStorageService = new TemporaryStorageServiceFactory.TemporaryStorageService(textFactory);
+            var textFactory = CreateMockTextFactoryService();
+            var temporaryStorageService = new TemporaryStorageServiceFactory.TemporaryStorageService(textFactory);
 
-                var text = Text.SourceText.From("Hello, World!", Encoding.ASCII);
+            var text = Text.SourceText.From("Hello, World!", Encoding.ASCII);
 
-                // Create a temporary storage location
-                using (var temporaryStorage = temporaryStorageService.CreateTemporaryTextStorage(System.Threading.CancellationToken.None))
-                {
-                    // Write text into it
-                    await temporaryStorage.WriteTextAsync(text);
+            // Create a temporary storage location
+            using (var temporaryStorage = temporaryStorageService.CreateTemporaryTextStorage(System.Threading.CancellationToken.None))
+            {
+                // Write text into it
+                await temporaryStorage.WriteTextAsync(text);
 
-                    // Read text back from it
-                    var text2 = await temporaryStorage.ReadTextAsync();
+                // Read text back from it
+                var text2 = await temporaryStorage.ReadTextAsync();
 
-                    Assert.NotSame(text, text2);
-                    Assert.Equal(text.ToString(), text2.ToString());
-                    Assert.Equal(text2.Encoding, Encoding.ASCII);
-                }
+                Assert.NotSame(text, text2);
+                Assert.Equal(text.ToString(), text2.ToString());
+                Assert.Equal(text2.Encoding, Encoding.ASCII);
             }
         }
 
-        private EditorTextFactoryService CreateMockTextFactoryService(Workspace workspace)
+        private EditorTextFactoryService CreateMockTextFactoryService()
         {
             var mockTextBufferFactoryService = new Mock<ITextBufferFactoryService>();
             mockTextBufferFactoryService
@@ -143,17 +123,24 @@ private EditorTextFactoryService CreateMockTextFactoryService(Workspace workspac
                     return mockTextBuffer.Object;
                 });
 
-            return new EditorTextFactoryService(workspace, mockTextBufferFactoryService.Object, new Mock<IContentTypeRegistryService>().Object);
+            return new EditorTextFactoryService(new FakeTextBufferCloneService(), mockTextBufferFactoryService.Object, new Mock<IContentTypeRegistryService>().Object);
         }
 
-        private void TestCreateTextInferredEncoding(Workspace workspace, byte[] bytes, Encoding defaultEncoding, Encoding expectedEncoding)
+        private void TestCreateTextInferredEncoding(byte[] bytes, Encoding defaultEncoding, Encoding expectedEncoding)
         {
-            var factory = CreateMockTextFactoryService(workspace);
+            var factory = CreateMockTextFactoryService();
             using (var stream = new MemoryStream(bytes))
             {
                 var text = factory.CreateText(stream, defaultEncoding);
                 Assert.Equal(expectedEncoding, text.Encoding);
             }
         }
+
+        private class FakeTextBufferCloneService : ITextBufferCloneService
+        {
+            public ITextBuffer Clone(SnapshotSpan span) => throw new NotImplementedException();
+
+            public ITextBuffer Clone(ITextImage textImage) => throw new NotImplementedException();
+        }
     }
 }

src/EditorFeatures/Text/Extensions.SnapshotSourceText.cs

@@ -24,36 +24,36 @@ private class SnapshotSourceText : SourceText
         {
             private static readonly Func<int, int, string> s_textLog = (v1, v2) => string.Format("FullRange : from {0} to {1}", v1, v2);
 
-            private readonly Workspace _workspace;
-
             /// <summary>
             /// The <see cref="ITextImage"/> backing the SourceText instance
             /// </summary>
             public readonly ITextImage TextImage;
 
+            private readonly ITextBufferCloneService _textBufferCloneServiceOpt;
+
             private readonly Encoding _encodingOpt;
             private readonly TextBufferContainer _containerOpt;
 
-            private SnapshotSourceText(Workspace workspace, ITextSnapshot editorSnapshot) :
-                this(workspace, editorSnapshot, TextBufferContainer.From(workspace, editorSnapshot.TextBuffer))
+            private SnapshotSourceText(ITextBufferCloneService textBufferCloneServiceOpt, ITextSnapshot editorSnapshot) :
+                this(textBufferCloneServiceOpt, editorSnapshot, TextBufferContainer.From(editorSnapshot.TextBuffer))
             {
             }
 
-            private SnapshotSourceText(Workspace workspace, ITextSnapshot editorSnapshot, TextBufferContainer container)
+            private SnapshotSourceText(ITextBufferCloneService textBufferCloneServiceOpt, ITextSnapshot editorSnapshot, TextBufferContainer container)
             {
                 Contract.ThrowIfNull(editorSnapshot);
 
-                _workspace = workspace;
+                _textBufferCloneServiceOpt = textBufferCloneServiceOpt;
                 this.TextImage = RecordReverseMapAndGetImage(editorSnapshot);
                 _encodingOpt = editorSnapshot.TextBuffer.GetEncodingOrUTF8();
                 _containerOpt = container;
             }
 
-            public SnapshotSourceText(Workspace workspace, ITextImage textImage, Encoding encodingOpt, TextBufferContainer containerOpt)
+            public SnapshotSourceText(ITextBufferCloneService textBufferCloneServiceOpt, ITextImage textImage, Encoding encodingOpt, TextBufferContainer containerOpt)
             {
                 Contract.ThrowIfNull(textImage);
 
-                _workspace = workspace;
+                _textBufferCloneServiceOpt = textBufferCloneServiceOpt;
                 this.TextImage = textImage;
                 _encodingOpt = encodingOpt;
                 _containerOpt = containerOpt;
@@ -70,9 +70,7 @@ public SnapshotSourceText(Workspace workspace, ITextImage textImage, Encoding en
             /// </summary>
             private static readonly ConditionalWeakTable<ITextImage, WeakReference<ITextSnapshot>> s_textImageToEditorSnapshotMap = new ConditionalWeakTable<ITextImage, WeakReference<ITextSnapshot>>();
 
-            internal Workspace Workspace => _workspace;
-
-            public static SourceText From(Workspace workspace, ITextSnapshot editorSnapshot)
+            public static SourceText From(ITextBufferCloneService textBufferCloneServiceOpt, ITextSnapshot editorSnapshot)
             {
                 if (editorSnapshot == null)
                 {
@@ -82,8 +80,8 @@ public static SourceText From(Workspace workspace, ITextSnapshot editorSnapshot)
                 if (!s_textSnapshotMap.TryGetValue(editorSnapshot, out var snapshot))
                 {
                     // Avoid capturing `workspace` on the fast path
-                    var tempWorkspace = workspace;
-                    snapshot = s_textSnapshotMap.GetValue(editorSnapshot, s => new SnapshotSourceText(tempWorkspace, s));
+                    var tempTextBufferCloneServiceOpt = textBufferCloneServiceOpt;
+                    snapshot = s_textSnapshotMap.GetValue(editorSnapshot, s => new SnapshotSourceText(tempTextBufferCloneServiceOpt, s));
                 }
 
                 return snapshot;
@@ -92,7 +90,7 @@ public static SourceText From(Workspace workspace, ITextSnapshot editorSnapshot)
             /// <summary>
             /// This only exist to break circular dependency on creating buffer. nobody except extension itself should use it
             /// </summary>
-            internal static SourceText From(Workspace workspace, ITextSnapshot editorSnapshot, TextBufferContainer container)
+            internal static SourceText From(ITextBufferCloneService textBufferCloneServiceOpt, ITextSnapshot editorSnapshot, TextBufferContainer container)
             {
                 if (editorSnapshot == null)
                 {
@@ -100,7 +98,7 @@ internal static SourceText From(Workspace workspace, ITextSnapshot editorSnapsho
                 }
 
                 Contract.ThrowIfFalse(editorSnapshot.TextBuffer == container.GetTextBuffer());
-                return s_textSnapshotMap.GetValue(editorSnapshot, s => new SnapshotSourceText(workspace, s, container));
+                return s_textSnapshotMap.GetValue(editorSnapshot, s => new SnapshotSourceText(textBufferCloneServiceOpt, s, container));
             }
 
             public override Encoding Encoding
@@ -111,14 +109,6 @@ public override Encoding Encoding
             public ITextSnapshot TryFindEditorSnapshot()
                 => TryFindEditorSnapshot(this.TextImage);
 
-            protected ITextBufferCloneService TextBufferFactory
-            {
-                get
-                {
-                    return _workspace?.Services.GetService<ITextBufferCloneService>();
-                }
-            }
-
             public override SourceTextContainer Container
             {
                 get
@@ -213,7 +203,7 @@ public override SourceText WithChanges(IEnumerable<TextChange> changes)
                 }
 
                 // check whether we can use text buffer factory
-                var factory = TextBufferFactory;
+                var factory = _textBufferCloneServiceOpt;
                 if (factory == null)
                 {
                     // if we can't get the factory, use the default implementation
@@ -236,7 +226,7 @@ public override SourceText WithChanges(IEnumerable<TextChange> changes)
                 }
 
                 return new ChangedSourceText(
-                    workspace: _workspace,
+                    textBufferCloneServiceOpt: _textBufferCloneServiceOpt,
                     baseText: this,
                     baseSnapshot: ((ITextSnapshot2)baseSnapshot).TextImage,
                     currentSnapshot: ((ITextSnapshot2)buffer.CurrentSnapshot).TextImage);
@@ -282,8 +272,8 @@ private static ITextSnapshot TryFindEditorSnapshot(ITextImage textImage)
             /// </summary>
             internal sealed class ClosedSnapshotSourceText : SnapshotSourceText
             {
-                public ClosedSnapshotSourceText(Workspace workspace, ITextImage textImage, Encoding encodingOpt)
-                    : base(workspace, textImage, encodingOpt, containerOpt: null)
+                public ClosedSnapshotSourceText(ITextBufferCloneService textBufferCloneServiceOpt, ITextImage textImage, Encoding encodingOpt)
+                    : base(textBufferCloneServiceOpt, textImage, encodingOpt, containerOpt: null)
                 {
                 }
             }
@@ -296,8 +286,8 @@ private class ChangedSourceText : SnapshotSourceText
                 private readonly SnapshotSourceText _baseText;
                 private readonly ITextImage _baseSnapshot;
 
-                public ChangedSourceText(Workspace workspace, SnapshotSourceText baseText, ITextImage baseSnapshot, ITextImage currentSnapshot)
-                    : base(workspace, currentSnapshot, baseText.Encoding, containerOpt: null)
+                public ChangedSourceText(ITextBufferCloneService textBufferCloneServiceOpt, SnapshotSourceText baseText, ITextImage baseSnapshot, ITextImage currentSnapshot)
+                    : base(textBufferCloneServiceOpt, currentSnapshot, baseText.Encoding, containerOpt: null)
                 {
                     _baseText = baseText;
                     _baseSnapshot = baseSnapshot;

src/EditorFeatures/Text/Extensions.TextBufferContainer.cs

@@ -4,7 +4,6 @@
 using System.Collections.Immutable;
 using System.Linq;
 using System.Runtime.CompilerServices;
-using System.Text;
 using Microsoft.VisualStudio.Text;
 using Roslyn.Utilities;
 
@@ -19,49 +18,39 @@ internal class TextBufferContainer : SourceTextContainer
         {
             private readonly WeakReference<ITextBuffer> _weakEditorBuffer;
             private readonly object _gate = new object();
+            private readonly ITextBufferCloneService _textBufferCloneServiceOpt;
 
             private event EventHandler<TextChangeEventArgs> EtextChanged;
             private SourceText _currentText;
 
-            private TextBufferContainer(Workspace workspace, ITextBuffer editorBuffer)
+            private TextBufferContainer(ITextBuffer editorBuffer)
             {
                 Contract.ThrowIfNull(editorBuffer);
 
                 _weakEditorBuffer = new WeakReference<ITextBuffer>(editorBuffer);
-                _currentText = SnapshotSourceText.From(workspace, editorBuffer.CurrentSnapshot, this);
+                editorBuffer.Properties.TryGetProperty(typeof(ITextBufferCloneService), out _textBufferCloneServiceOpt);
+                _currentText = SnapshotSourceText.From(_textBufferCloneServiceOpt, editorBuffer.CurrentSnapshot, this);
             }
 
             /// <summary>
             /// A weak map of all Editor ITextBuffers and their associated SourceTextContainer
             /// </summary>
             private static readonly ConditionalWeakTable<ITextBuffer, TextBufferContainer> s_textContainerMap = new ConditionalWeakTable<ITextBuffer, TextBufferContainer>();
-            private static readonly ConditionalWeakTable<ITextBuffer, TextBufferContainer>.CreateValueCallback s_createContainerWithoutWorkspaceCallback = CreateContainer;
+            private static readonly ConditionalWeakTable<ITextBuffer, TextBufferContainer>.CreateValueCallback s_createContainerCallback = CreateContainer;
 
-            public static TextBufferContainer From(Workspace workspace, ITextBuffer buffer)
+            public static TextBufferContainer From(ITextBuffer buffer)
             {
                 if (buffer == null)
                 {
                     throw new ArgumentNullException(nameof(buffer));
                 }
 
-                if (workspace is null)
-                {
-                    return s_textContainerMap.GetValue(buffer, s_createContainerWithoutWorkspaceCallback);
-                }
-
-                if (!s_textContainerMap.TryGetValue(buffer, out var container))
-                {
-                    // Avoid capturing 'workspace' on the fast path
-                    var workspaceCopy = workspace;
-                    container = s_textContainerMap.GetValue(buffer, key => new TextBufferContainer(workspace, key));
-                }
-
-                return container;
+                return s_textContainerMap.GetValue(buffer, s_createContainerCallback);
             }
 
             private static TextBufferContainer CreateContainer(ITextBuffer editorBuffer)
             {
-                return new TextBufferContainer(workspace: null, editorBuffer);
+                return new TextBufferContainer(editorBuffer);
             }
 
             public ITextBuffer TryFindEditorTextBuffer()
@@ -122,7 +111,7 @@ private void OnTextContentChanged(object sender, TextContentChangedEventArgs arg
 
                 // this should convert given editor snapshots to roslyn forked snapshots
                 var oldText = (SnapshotSourceText)args.Before.AsText();
-                var newText = SnapshotSourceText.From(oldText.Workspace, args.After);
+                var newText = SnapshotSourceText.From(_textBufferCloneServiceOpt, args.After);
                 _currentText = newText;
 
                 var changes = ImmutableArray.CreateRange(args.Changes.Select(c => new TextChangeRange(new TextSpan(c.OldSpan.Start, c.OldSpan.Length), c.NewLength)));

src/EditorFeatures/Text/Extensions.cs

@@ -12,7 +12,7 @@ namespace Microsoft.CodeAnalysis.Text
     public static partial class Extensions
     {
         public static SourceTextContainer AsTextContainer(this ITextBuffer buffer)
-            => TextBufferContainer.From(workspace: null, buffer);
+            => TextBufferContainer.From(buffer);
 
         public static ITextBuffer GetTextBuffer(this SourceTextContainer textContainer)
             => TryGetTextBuffer(textContainer) ?? throw new ArgumentException(TextEditorResources.textContainer_is_not_a_SourceTextContainer_that_was_created_from_an_ITextBuffer, nameof(textContainer));
@@ -37,10 +37,10 @@ internal static TextLine AsTextLine(this ITextSnapshotLine line)
             => line.Snapshot.AsText().Lines[line.LineNumber];
 
         public static SourceText AsText(this ITextSnapshot textSnapshot)
-            => SnapshotSourceText.From(workspace: null, textSnapshot);
+            => SnapshotSourceText.From(textBufferCloneServiceOpt: null, textSnapshot);
 
-        internal static SourceText AsRoslynText(this ITextSnapshot textSnapshot, Workspace workspace, Encoding encoding)
-            => new SnapshotSourceText.ClosedSnapshotSourceText(workspace, ((ITextSnapshot2)textSnapshot).TextImage, encoding);
+        internal static SourceText AsRoslynText(this ITextSnapshot textSnapshot, ITextBufferCloneService textBufferCloneServiceOpt, Encoding encoding)
+            => new SnapshotSourceText.ClosedSnapshotSourceText(textBufferCloneServiceOpt, ((ITextSnapshot2)textSnapshot).TextImage, encoding);
 
         /// <summary>
         /// Gets the workspace corresponding to the text buffer.

src/EditorFeatures/Text/Implementation/TextBufferFactoryService/TextBufferCloneServiceFactory.cs

@@ -16,9 +16,9 @@ internal class TextBufferCloneServiceFactory : IWorkspaceServiceFactory
         [ImportingConstructor]
         public TextBufferCloneServiceFactory(
             ITextBufferFactoryService textBufferFactoryService,
-            IContentTypeRegistryService contentTypeRegistry)
+            IContentTypeRegistryService contentTypeRegistryService)
         {
-            _singleton = new TextBufferCloneService((ITextBufferFactoryService3)textBufferFactoryService, contentTypeRegistry.UnknownContentType);
+            _singleton = new TextBufferCloneService((ITextBufferFactoryService3)textBufferFactoryService, contentTypeRegistryService);
         }
 
         public IWorkspaceService CreateService(HostWorkspaceServices workspaceServices)
@@ -26,15 +26,17 @@ public IWorkspaceService CreateService(HostWorkspaceServices workspaceServices)
             return _singleton;
         }
 
+        [Export(typeof(ITextBufferCloneService)), Shared]
         private class TextBufferCloneService : ITextBufferCloneService
         {
             private readonly ITextBufferFactoryService3 _textBufferFactoryService;
             private readonly IContentType _unknownContentType;
 
-            public TextBufferCloneService(ITextBufferFactoryService3 textBufferFactoryService, IContentType unknownContentType)
+            [ImportingConstructor]
+            public TextBufferCloneService(ITextBufferFactoryService3 textBufferFactoryService, IContentTypeRegistryService contentTypeRegistryService)
             {
                 _textBufferFactoryService = textBufferFactoryService;
-                _unknownContentType = unknownContentType;
+                _unknownContentType = contentTypeRegistryService.UnknownContentType;
             }
 
             public ITextBuffer Clone(SnapshotSpan span)

src/VisualStudio/Core/Def/Implementation/ProjectSystem/VisualStudioWorkspaceImpl.cs

@@ -22,6 +22,7 @@
 using Microsoft.VisualStudio.LanguageServices.Utilities;
 using Microsoft.VisualStudio.Shell;
 using Microsoft.VisualStudio.Shell.Interop;
+using Microsoft.VisualStudio.Text;
 using Roslyn.Utilities;
 using VSLangProj;
 using VSLangProj140;
@@ -37,6 +38,9 @@ internal abstract partial class VisualStudioWorkspaceImpl : VisualStudioWorkspac
         private static readonly IntPtr s_docDataExisting_Unknown = new IntPtr(-1);
         private const string AppCodeFolderName = "App_Code";
 
+        private readonly ITextBufferFactoryService _textBufferFactoryService;
+        private readonly ITextBufferCloneService _textBufferCloneService;
+
         // document worker coordinator
         private ISolutionCrawlerRegistrationService _registrationService;
 
@@ -58,6 +62,9 @@ public VisualStudioWorkspaceImpl(ExportProvider exportProvider)
                 MefV1HostServices.Create(exportProvider),
                 backgroundWork: WorkspaceBackgroundWork.ParseAndCompile)
         {
+            _textBufferCloneService = exportProvider.GetExportedValue<ITextBufferCloneService>();
+            _textBufferFactoryService = exportProvider.GetExportedValue<ITextBufferFactoryService>();
+            _textBufferFactoryService.TextBufferCreated += AddTextBufferCloneServiceToBuffer;
             exportProvider.GetExportedValue<PrimaryWorkspace>().Register(this);
         }
 
@@ -213,6 +220,11 @@ protected override bool CanApplyParseOptionChange(ParseOptions oldOptions, Parse
             return newOptions == updated;
         }
 
+        private void AddTextBufferCloneServiceToBuffer(object sender, TextBufferCreatedEventArgs e)
+        {
+            e.TextBuffer.Properties.AddProperty(typeof(ITextBufferCloneService), _textBufferCloneService);
+        }
+
         public override bool CanApplyChange(ApplyChangesKind feature)
         {
             switch (feature)
@@ -1081,6 +1093,11 @@ internal void StopSolutionCrawler()
 
         protected override void Dispose(bool finalize)
         {
+            if (!finalize)
+            {
+                _textBufferFactoryService.TextBufferCreated -= AddTextBufferCloneServiceToBuffer;
+            }
+
             // workspace is going away. unregister this workspace from work coordinator
             StopSolutionCrawler();