Merge remote-tracking branch 'dotnet/master' into Fix5130SecondTry

src/Compilers/Core/Portable/CvtRes.cs

@@ -12,6 +12,7 @@
 using WCHAR = System.Char;
 using WORD = System.UInt16;
 using System.Reflection.PortableExecutable;
+using Roslyn.Utilities;
 
 namespace Microsoft.CodeAnalysis
 {
@@ -204,9 +205,9 @@ static internal Microsoft.Cci.ResourceSection ReadWin32ResourcesFromCOFF(Stream
             var imageResourceSectionBytes = new byte[checked(rsrc1.SizeOfRawData + rsrc2.SizeOfRawData)];
 
             stream.Seek(rsrc1.PointerToRawData, SeekOrigin.Begin);
-            stream.Read(imageResourceSectionBytes, 0, rsrc1.SizeOfRawData);
+            stream.TryReadAll(imageResourceSectionBytes, 0, rsrc1.SizeOfRawData); // ConfirmSectionValues ensured that data are available
             stream.Seek(rsrc2.PointerToRawData, SeekOrigin.Begin);
-            stream.Read(imageResourceSectionBytes, rsrc1.SizeOfRawData, rsrc2.SizeOfRawData);
+            stream.TryReadAll(imageResourceSectionBytes, rsrc1.SizeOfRawData, rsrc2.SizeOfRawData); // ConfirmSectionValues ensured that data are available
 
             const int SizeOfRelocationEntry = 10;
 

src/Compilers/Core/Portable/EncodedStringText.cs

@@ -219,7 +219,7 @@ private static bool TryGetByteArrayFromFileStream(Stream stream, out byte[] buff
             // than the buffer size. The default buffer size is 4KB, so this will incur a 4KB
             // allocation for any files less than 4KB. That's why, for example, the command
             // line compiler actually specifies a very small buffer size.
-            return stream.Read(buffer, 0, length) == length;
+            return stream.TryReadAll(buffer, 0, length) == length;
         }
     }
 }

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

@@ -24,9 +24,13 @@ public void Commit(int grfCommitFlags)
             _stream.Flush();
         }
 
+        /// <summary>
+        /// The actual number of bytes read can be fewer than the number of bytes requested 
+        /// if an error occurs or if the end of the stream is reached during the read operation.
+        /// </summary>
         public unsafe void Read(byte[] pv, int cb, IntPtr pcbRead)
         {
-            int bytesRead = _stream.Read(pv, 0, cb);
+            int bytesRead = _stream.TryReadAll(pv, 0, cb);
 
             if (pcbRead != IntPtr.Zero)
             {

src/Compilers/Core/Portable/PEWriter/BlobWriter.cs

@@ -186,7 +186,7 @@ public int WriteBytes(Stream source, int byteCount)
             }
 
             int start = Advance(byteCount);
-            int bytesRead = source.Read(_buffer, start, byteCount);
+            int bytesRead = source.TryReadAll(_buffer, start, byteCount);
             _position = start + bytesRead;
             return bytesRead;
         }

src/Debugging/Microsoft.DiaSymReader.PortablePdb.Tests/Microsoft.DiaSymReader.PortablePdb.UnitTests.csproj

@@ -92,6 +92,9 @@
     <Compile Include="..\..\Compilers\Core\Portable\InternalUtilities\ComStreamWrapper.cs">
       <Link>TestHelpers\ComStreamWrapper.cs</Link>
     </Compile>
+    <Compile Include="..\..\Compilers\Core\Portable\InternalUtilities\StreamExtensions.cs">
+      <Link>TestHelpers\StreamExtensions.cs</Link>
+    </Compile>
   </ItemGroup>
   <ItemGroup>
     <Compile Include="TestHelpers\AssertEx.cs" />

src/EditorFeatures/Test/project.lock.json

@@ -60,6 +60,14 @@
           "lib/net40/Moq.dll": {}
         }
       },
+      "Newtonsoft.Json/6.0.4": {
+        "compile": {
+          "lib/net45/Newtonsoft.Json.dll": {}
+        },
+        "runtime": {
+          "lib/net45/Newtonsoft.Json.dll": {}
+        }
+      },
       "System.AppContext/4.0.0": {
         "dependencies": {
           "System.Runtime": "[4.0.0, )"
@@ -370,6 +378,14 @@
           "lib/net40/Moq.dll": {}
         }
       },
+      "Newtonsoft.Json/6.0.4": {
+        "compile": {
+          "lib/net45/Newtonsoft.Json.dll": {}
+        },
+        "runtime": {
+          "lib/net45/Newtonsoft.Json.dll": {}
+        }
+      },
       "System.AppContext/4.0.0": {
         "dependencies": {
           "System.Runtime": "[4.0.0, )"
@@ -790,6 +806,31 @@
         "package/services/metadata/core-properties/98e2d674c8ec4e5fbda07a9e01280647.psmdcp"
       ]
     },
+    "Newtonsoft.Json/6.0.4": {
+      "sha512": "FyQLmEpjsCrEP+znauLDGAi+h6i9YnaMkITlfIoiM4RYyX3nki306bTHsr/0okiIvIc7BJhQTbOAIZVocccFUw==",
+      "type": "Package",
+      "files": [
+        "[Content_Types].xml",
+        "_rels/.rels",
+        "lib/net20/Newtonsoft.Json.dll",
+        "lib/net20/Newtonsoft.Json.xml",
+        "lib/net35/Newtonsoft.Json.dll",
+        "lib/net35/Newtonsoft.Json.xml",
+        "lib/net40/Newtonsoft.Json.dll",
+        "lib/net40/Newtonsoft.Json.xml",
+        "lib/net45/Newtonsoft.Json.dll",
+        "lib/net45/Newtonsoft.Json.xml",
+        "lib/netcore45/Newtonsoft.Json.dll",
+        "lib/netcore45/Newtonsoft.Json.xml",
+        "lib/portable-net40+sl5+wp80+win8+wpa81/Newtonsoft.Json.dll",
+        "lib/portable-net40+sl5+wp80+win8+wpa81/Newtonsoft.Json.xml",
+        "lib/portable-net45+wp80+win8+wpa81/Newtonsoft.Json.dll",
+        "lib/portable-net45+wp80+win8+wpa81/Newtonsoft.Json.xml",
+        "Newtonsoft.Json.nuspec",
+        "package/services/metadata/core-properties/87a0a4e28d50417ea282e20f81bc6477.psmdcp",
+        "tools/install.ps1"
+      ]
+    },
     "System.AppContext/4.0.0": {
       "sha512": "gUoYgAWDC3+xhKeU5KSLbYDhTdBYk9GssrMSCcWUADzOglW+s0AmwVhOUGt2tL5xUl7ZXoYTPdA88zCgKrlG0A==",
       "type": "Package",

src/EditorFeatures/VisualBasicTest/Diagnostics/Spellcheck/SpellcheckTests.vb

@@ -372,7 +372,9 @@ End Module</File>
             Test(text, expected)
         End Sub
 
-        <Fact, Trait(Traits.Feature, Traits.Features.CodeActionsSpellcheck)>
+        <ConditionalFact(GetType(x86))>
+        <Trait(Traits.Feature, Traits.Features.CodeActionsSpellcheck)>
+        <WorkItem(5391, "https://github.com/dotnet/roslyn/issues/5391")>
         Public Sub SuggestEscapedPredefinedTypes()
             Dim text = <File>
 Imports System

src/Features/Core/Portable/Diagnostics/Log/DiagnosticAnalyzerLogger.cs

@@ -21,12 +21,16 @@ internal class DiagnosticAnalyzerLogger
         private const string AnalyzerException = "Analyzer.Exception";
         private const string AnalyzerExceptionHashCode = "Analyzer.ExceptionHashCode";
 
-        private static readonly SHA256CryptoServiceProvider s_sha256CryptoServiceProvider = new SHA256CryptoServiceProvider();
-
+        private static readonly SHA256CryptoServiceProvider s_sha256CryptoServiceProvider = GetSha256CryptoServiceProvider();
         private static readonly ConditionalWeakTable<DiagnosticAnalyzer, StrongBox<bool>> s_telemetryCache = new ConditionalWeakTable<DiagnosticAnalyzer, StrongBox<bool>>();
 
         private static string ComputeSha256Hash(string name)
         {
+            if (s_sha256CryptoServiceProvider == null)
+            {
+                return "Hash Provider Not Available";
+            }
+
             byte[] hash = s_sha256CryptoServiceProvider.ComputeHash(Encoding.UTF8.GetBytes(name));
             return Convert.ToBase64String(hash);
         }
@@ -170,5 +174,18 @@ private static bool CheckTelemetry(DiagnosticAnalyzerService service, Diagnostic
             DiagnosticDescriptor diagnostic = diagDescriptors.Length > 0 ? diagDescriptors[0] : null;
             return diagnostic == null ? false : diagnostic.CustomTags.Any(t => t == WellKnownDiagnosticTags.Telemetry);
         }
+
+        private static SHA256CryptoServiceProvider GetSha256CryptoServiceProvider()
+        {
+            try
+            {
+                // not all environment allows SHA256 encryption
+                return new SHA256CryptoServiceProvider();
+            }
+            catch
+            {
+                return null;
+            }
+        }
     }
 }

src/Interactive/EditorFeatures/Core/InteractiveEditorFeatures.csproj

@@ -131,7 +131,6 @@
     <Compile Include="Extensibility\Interactive\InteractiveEvaluator.cs" />
     <Compile Include="Extensibility\Interactive\InteractiveMetadataReferenceResolver.cs" />
     <Compile Include="Extensibility\Interactive\CSharpVBInteractiveCommandContentTypes.cs" />
-    <Compile Include="Extensibility\Interactive\NuGetPackageResolverImpl.cs" />
     <Compile Include="Implementation\Completion\InteractiveCommandCompletionService.cs" />
     <Compile Include="Implementation\Completion\Presentation\CompletionPresenter.cs" />
     <Compile Include="Implementation\Interactive\InertClassifierProvider.cs" />

src/Interactive/Features/Interactive/Core/InteractiveHost.Service.cs

@@ -25,7 +25,6 @@
 using Roslyn.Utilities;
 
 using RuntimeMetadataReferenceResolver = WORKSPACES::Microsoft.CodeAnalysis.Scripting.Hosting.RuntimeMetadataReferenceResolver;
-using NuGetPackageResolver = WORKSPACES::Microsoft.CodeAnalysis.Scripting.Hosting.NuGetPackageResolver;
 using GacFileResolver = WORKSPACES::Microsoft.CodeAnalysis.Scripting.Hosting.GacFileResolver;
 
 namespace Microsoft.CodeAnalysis.Interactive
@@ -166,9 +165,13 @@ public void Initialize(Type replServiceProviderType)
 
             private MetadataReferenceResolver CreateMetadataReferenceResolver(ImmutableArray<string> searchPaths, string baseDirectory)
             {
+                var userProfilePath = Environment.GetFolderPath(Environment.SpecialFolder.UserProfile);
+                var packagesDirectory = string.IsNullOrEmpty(userProfilePath) ?
+                    null :
+                    Path.Combine(userProfilePath, Path.Combine(".nuget", "packages"));
                 return new RuntimeMetadataReferenceResolver(
                    new RelativePathResolver(searchPaths, baseDirectory),
-                   null, // TODO
+                    string.IsNullOrEmpty(packagesDirectory) ? null : new NuGetPackageResolverImpl(packagesDirectory),
                    new GacFileResolver(
                        architectures: GacFileResolver.Default.Architectures,  // TODO (tomat)
                        preferredCulture: CultureInfo.CurrentCulture), // TODO (tomat)

src/Interactive/EditorFeatures/Core/Extensibility/Interactive/NuGetPackageResolverImpl.cs → src/Interactive/Features/Interactive/Core/NuGetPackageResolverImpl.cs

@@ -10,13 +10,23 @@
 using System.Diagnostics;
 using System.IO;
 using System.Reflection;
+using NuGetPackageResolver = WORKSPACES::Microsoft.CodeAnalysis.Scripting.Hosting.NuGetPackageResolver;
 
-namespace Microsoft.CodeAnalysis.Editor.Interactive
+namespace Microsoft.CodeAnalysis.Interactive
 {
-    internal sealed class NuGetPackageResolverImpl : WORKSPACES::Microsoft.CodeAnalysis.Scripting.Hosting.NuGetPackageResolver
+    internal sealed class NuGetPackageResolverImpl : NuGetPackageResolver
     {
         private const string ProjectJsonFramework = "net46";
         private const string ProjectLockJsonFramework = ".NETFramework,Version=v4.6";
+        private const string EmptyNuGetConfig =
+@"<?xml version=""1.0"" encoding=""utf-8""?>
+<configuration>
+  <packageRestore>
+    <add key=""enabled"" value=""True"" />
+    <add key=""automatic"" value=""False"" />
+  </packageRestore>
+  <packageSources/>
+</configuration>";
 
         private readonly string _packagesDirectory;
         private readonly Action<ProcessStartInfo> _restore;
@@ -28,35 +38,39 @@ internal NuGetPackageResolverImpl(string packagesDirectory, Action<ProcessStartI
             _restore = restore ?? NuGetRestore;
         }
 
-        internal override ImmutableArray<string> ResolveNuGetPackage(string reference)
+        internal new static bool TryParsePackageReference(string reference, out string name, out string version)
         {
-            string packageName;
-            string packageVersion;
-            if (!ParsePackageReference(reference, out packageName, out packageVersion))
-            {
-                return default(ImmutableArray<string>);
-            }
+            return NuGetPackageResolver.TryParsePackageReference(reference, out name, out version);
+        }
 
+        internal override ImmutableArray<string> ResolveNuGetPackage(string packageName, string packageVersion)
+        {
             try
             {
-                var tempPath = PathUtilities.CombineAbsoluteAndRelativePaths(Path.GetTempPath(), Guid.NewGuid().ToString("D"));
+                var tempPath = Path.Combine(Path.GetTempPath(), Guid.NewGuid().ToString("D"));
                 var tempDir = Directory.CreateDirectory(tempPath);
                 try
                 {
                     // Create project.json.
-                    var projectJson = PathUtilities.CombineAbsoluteAndRelativePaths(tempPath, "project.json");
-                    using (var stream = File.OpenWrite(projectJson))
+                    var projectJsonPath = Path.Combine(tempPath, "project.json");
+                    using (var stream = File.OpenWrite(projectJsonPath))
                     using (var writer = new StreamWriter(stream))
                     {
                         WriteProjectJson(writer, packageName, packageVersion);
                     }
 
-                    // Run "nuget.exe restore project.json" to generate project.lock.json.
-                    NuGetRestore(projectJson);
+                    // Create nuget.config with no package sources so restore
+                    // uses the local cache only, no downloading.
+                    var configPath = Path.Combine(tempPath, "nuget.config");
+                    File.WriteAllText(configPath, EmptyNuGetConfig);
+
+                    // Run "nuget.exe restore project.json -configfile nuget.config"
+                    // to generate project.lock.json.
+                    NuGetRestore(projectJsonPath, configPath);
 
                     // Read the references from project.lock.json.
-                    var projectLockJson = PathUtilities.CombineAbsoluteAndRelativePaths(tempPath, "project.lock.json");
-                    using (var stream = File.OpenRead(projectLockJson))
+                    var projectLockJsonPath = Path.Combine(tempPath, "project.lock.json");
+                    using (var stream = File.OpenRead(projectLockJsonPath))
                     using (var reader = new StreamReader(stream))
                     {
                         return ReadProjectLockJson(_packagesDirectory, reader);
@@ -76,25 +90,6 @@ internal override ImmutableArray<string> ResolveNuGetPackage(string reference)
             return default(ImmutableArray<string>);
         }
 
-        /// <summary>
-        /// Syntax is "id/version", matching references in project.lock.json.
-        /// </summary>
-        internal static bool ParsePackageReference(string reference, out string name, out string version)
-        {
-            var parts = reference.Split('/');
-            if ((parts.Length == 2) &&
-                (parts[0].Length > 0) &&
-                (parts[1].Length > 0))
-            {
-                name = parts[0];
-                version = parts[1];
-                return true;
-            }
-            name = null;
-            version = null;
-            return false;
-        }
-
         /// <summary>
         /// Generate a project.json file with the packages as "dependencies".
         /// </summary>
@@ -139,7 +134,7 @@ internal static ImmutableArray<string> ReadProjectLockJson(string packagesDirect
                 {
                     foreach (var package in (JObject)target.Value)
                     {
-                        var packageRoot = PathUtilities.CombineAbsoluteAndRelativePaths(packagesDirectory, package.Key);
+                        var packageRoot = Path.Combine(packagesDirectory, package.Key);
                         var runtime = (JObject)GetPropertyValue((JObject)package.Value, "runtime");
                         if (runtime == null)
                         {
@@ -147,8 +142,14 @@ internal static ImmutableArray<string> ReadProjectLockJson(string packagesDirect
                         }
                         foreach (var item in runtime)
                         {
-                            var path = PathUtilities.CombinePossiblyRelativeAndRelativePaths(packageRoot, item.Key);
-                            builder.Add(path);
+                            var relativePath = item.Key;
+                            // Ignore placeholder "_._" files.
+                            var name = Path.GetFileName(relativePath);
+                            if (string.Equals(name, "_._", StringComparison.InvariantCulture))
+                            {
+                                continue;
+                            }
+                            builder.Add(Path.Combine(packageRoot, relativePath));
                         }
                     }
                     break;
@@ -164,17 +165,17 @@ private static JToken GetPropertyValue(JObject obj, string propertyName)
             return value;
         }
 
-        private void NuGetRestore(string projectJsonPath)
+        private void NuGetRestore(string projectJsonPath, string configPath)
         {
             // Load nuget.exe from same directory as current assembly.
-            var nugetExePath = PathUtilities.CombineAbsoluteAndRelativePaths(
-                PathUtilities.GetDirectoryName(
+            var nugetExePath = Path.Combine(
+                Path.GetDirectoryName(
                     CorLightup.Desktop.GetAssemblyLocation(typeof(NuGetPackageResolverImpl).GetTypeInfo().Assembly)),
                 "nuget.exe");
             var startInfo = new ProcessStartInfo()
             {
                 FileName = nugetExePath,
-                Arguments = $"restore \"{projectJsonPath}\" -PackagesDirectory \"{_packagesDirectory}\"",
+                Arguments = $"restore \"{projectJsonPath}\" -ConfigFile \"{configPath}\" -PackagesDirectory \"{_packagesDirectory}\"",
                 CreateNoWindow = true,
                 UseShellExecute = false,
                 RedirectStandardOutput = true,

src/Interactive/Features/InteractiveFeatures.csproj

@@ -94,6 +94,7 @@
     <Compile Include="Interactive\Core\HostObject\SearchPaths.cs" />
     <Compile Include="Interactive\Core\SerializableAssemblyLoadResult.cs" />
     <Compile Include="Interactive\Core\HostObject\SynchronizedVersionedList.cs" />
+    <Compile Include="Interactive\Core\NuGetPackageResolverImpl.cs" />
   </ItemGroup>
   <ItemGroup>
     <Compile Include="Interactive\Core\InteractiveHost.LazyRemoteService.cs" />

src/Interactive/Features/project.json

 {
   "dependencies": {
     "Microsoft.Composition": "1.0.27",
+    "Newtonsoft.Json": "6.0.4",
     "System.Collections": "4.0.10",
     "System.Diagnostics.Debug": "4.0.10",
     "System.Globalization": "4.0.10",

src/Interactive/Features/project.lock.json

@@ -28,6 +28,14 @@
           "lib/net45/_._": {}
         }
       },
+      "Newtonsoft.Json/6.0.4": {
+        "compile": {
+          "lib/net45/Newtonsoft.Json.dll": {}
+        },
+        "runtime": {
+          "lib/net45/Newtonsoft.Json.dll": {}
+        }
+      },
       "System.AppContext/4.0.0": {
         "dependencies": {
           "System.Runtime": "[4.0.0, )"
@@ -377,6 +385,31 @@
         "runtimes/aot/lib/netcore50/System.Xml.Serialization.dll"
       ]
     },
+    "Newtonsoft.Json/6.0.4": {
+      "sha512": "FyQLmEpjsCrEP+znauLDGAi+h6i9YnaMkITlfIoiM4RYyX3nki306bTHsr/0okiIvIc7BJhQTbOAIZVocccFUw==",
+      "type": "Package",
+      "files": [
+        "[Content_Types].xml",
+        "_rels/.rels",
+        "lib/net20/Newtonsoft.Json.dll",
+        "lib/net20/Newtonsoft.Json.xml",
+        "lib/net35/Newtonsoft.Json.dll",
+        "lib/net35/Newtonsoft.Json.xml",
+        "lib/net40/Newtonsoft.Json.dll",
+        "lib/net40/Newtonsoft.Json.xml",
+        "lib/net45/Newtonsoft.Json.dll",
+        "lib/net45/Newtonsoft.Json.xml",
+        "lib/netcore45/Newtonsoft.Json.dll",
+        "lib/netcore45/Newtonsoft.Json.xml",
+        "lib/portable-net40+sl5+wp80+win8+wpa81/Newtonsoft.Json.dll",
+        "lib/portable-net40+sl5+wp80+win8+wpa81/Newtonsoft.Json.xml",
+        "lib/portable-net45+wp80+win8+wpa81/Newtonsoft.Json.dll",
+        "lib/portable-net45+wp80+win8+wpa81/Newtonsoft.Json.xml",
+        "Newtonsoft.Json.nuspec",
+        "package/services/metadata/core-properties/87a0a4e28d50417ea282e20f81bc6477.psmdcp",
+        "tools/install.ps1"
+      ]
+    },
     "System.AppContext/4.0.0": {
       "sha512": "gUoYgAWDC3+xhKeU5KSLbYDhTdBYk9GssrMSCcWUADzOglW+s0AmwVhOUGt2tL5xUl7ZXoYTPdA88zCgKrlG0A==",
       "type": "Package",
@@ -1164,6 +1197,7 @@
   "projectFileDependencyGroups": {
     "": [
       "Microsoft.Composition >= 1.0.27",
+      "Newtonsoft.Json >= 6.0.4",
       "System.Collections >= 4.0.10",
       "System.Diagnostics.Debug >= 4.0.10",
       "System.Globalization >= 4.0.10",

src/Interactive/Host/project.lock.json

@@ -28,6 +28,14 @@
           "lib/net45/_._": {}
         }
       },
+      "Newtonsoft.Json/6.0.4": {
+        "compile": {
+          "lib/net45/Newtonsoft.Json.dll": {}
+        },
+        "runtime": {
+          "lib/net45/Newtonsoft.Json.dll": {}
+        }
+      },
       "System.AppContext/4.0.0": {
         "dependencies": {
           "System.Runtime": "[4.0.0, )"
@@ -287,6 +295,14 @@
           "lib/net45/_._": {}
         }
       },
+      "Newtonsoft.Json/6.0.4": {
+        "compile": {
+          "lib/net45/Newtonsoft.Json.dll": {}
+        },
+        "runtime": {
+          "lib/net45/Newtonsoft.Json.dll": {}
+        }
+      },
       "System.AppContext/4.0.0": {
         "dependencies": {
           "System.Runtime": "[4.0.0, )"
@@ -636,6 +652,31 @@
         "runtimes/aot/lib/netcore50/System.Xml.Serialization.dll"
       ]
     },
+    "Newtonsoft.Json/6.0.4": {
+      "sha512": "FyQLmEpjsCrEP+znauLDGAi+h6i9YnaMkITlfIoiM4RYyX3nki306bTHsr/0okiIvIc7BJhQTbOAIZVocccFUw==",
+      "type": "Package",
+      "files": [
+        "[Content_Types].xml",
+        "_rels/.rels",
+        "lib/net20/Newtonsoft.Json.dll",
+        "lib/net20/Newtonsoft.Json.xml",
+        "lib/net35/Newtonsoft.Json.dll",
+        "lib/net35/Newtonsoft.Json.xml",
+        "lib/net40/Newtonsoft.Json.dll",
+        "lib/net40/Newtonsoft.Json.xml",
+        "lib/net45/Newtonsoft.Json.dll",
+        "lib/net45/Newtonsoft.Json.xml",
+        "lib/netcore45/Newtonsoft.Json.dll",
+        "lib/netcore45/Newtonsoft.Json.xml",
+        "lib/portable-net40+sl5+wp80+win8+wpa81/Newtonsoft.Json.dll",
+        "lib/portable-net40+sl5+wp80+win8+wpa81/Newtonsoft.Json.xml",
+        "lib/portable-net45+wp80+win8+wpa81/Newtonsoft.Json.dll",
+        "lib/portable-net45+wp80+win8+wpa81/Newtonsoft.Json.xml",
+        "Newtonsoft.Json.nuspec",
+        "package/services/metadata/core-properties/87a0a4e28d50417ea282e20f81bc6477.psmdcp",
+        "tools/install.ps1"
+      ]
+    },
     "System.AppContext/4.0.0": {
       "sha512": "gUoYgAWDC3+xhKeU5KSLbYDhTdBYk9GssrMSCcWUADzOglW+s0AmwVhOUGt2tL5xUl7ZXoYTPdA88zCgKrlG0A==",
       "type": "Package",

src/Interactive/HostTest/NuGetPackageResolverTests.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.Editor.Interactive;
+using Microsoft.CodeAnalysis.Interactive;
 using Microsoft.CodeAnalysis.Test.Utilities;
 using Roslyn.Test.Utilities;
 using Roslyn.Utilities;
@@ -13,6 +13,9 @@ namespace Microsoft.CodeAnalysis.UnitTests.Interactive
 {
     public class NuGetPackageResolverTests : TestBase
     {
+        /// <summary>
+        /// Valid reference.
+        /// </summary>
         [ConditionalFact(typeof(WindowsOnly))]
         public void ResolveReference()
         {
@@ -25,6 +28,15 @@ public void ResolveReference()
     ""net46"": {}
   }
 }";
+            var expectedConfig =
+@"<?xml version=""1.0"" encoding=""utf-8""?>
+<configuration>
+  <packageRestore>
+    <add key=""enabled"" value=""True"" />
+    <add key=""automatic"" value=""False"" />
+  </packageRestore>
+  <packageSources/>
+</configuration>";
             var actualProjectLockJson =
 @"{
   ""locked"": false,
@@ -48,6 +60,11 @@ public void ResolveReference()
           ""System.Runtime"": """"
         },
       },
+      ""System.Runtime/4.0.0"": {
+        ""runtime"": {
+          ""ref/dotnet/_._"": {}
+        }
+      },
       ""System.IO/4.0.10"": {
         ""dependencies"": {},
         ""runtime"": {
@@ -65,23 +82,32 @@ public void ResolveReference()
                     packagesDirectory,
                     startInfo =>
                     {
+                        // Verify arguments.
                         var arguments = startInfo.Arguments.Split('"');
-                        Assert.Equal(5, arguments.Length);
+                        Assert.Equal(7, arguments.Length);
                         Assert.Equal("restore ", arguments[0]);
                         Assert.Equal("project.json", PathUtilities.GetFileName(arguments[1]));
-                        Assert.Equal(" -PackagesDirectory ", arguments[2]);
-                        Assert.Equal(packagesDirectory, arguments[3]);
-                        Assert.Equal("", arguments[4]);
+                        Assert.Equal(" -ConfigFile ", arguments[2]);
+                        Assert.Equal("nuget.config", PathUtilities.GetFileName(arguments[3]));
+                        Assert.Equal(" -PackagesDirectory ", arguments[4]);
+                        Assert.Equal(packagesDirectory, arguments[5]);
+                        Assert.Equal("", arguments[6]);
+                        // Verify project.json contents.
                         var projectJsonPath = arguments[1];
                         var actualProjectJson = File.ReadAllText(projectJsonPath);
                         Assert.Equal(expectedProjectJson, actualProjectJson);
+                        // Verify config file contents.
+                        var configPath = arguments[3];
+                        var actualConfig = File.ReadAllText(configPath);
+                        Assert.Equal(expectedConfig, actualConfig);
+                        // Generate project.lock.json.
                         var projectLockJsonPath = PathUtilities.CombineAbsoluteAndRelativePaths(PathUtilities.GetDirectoryName(projectJsonPath), "project.lock.json");
                         using (var writer = new StreamWriter(projectLockJsonPath))
                         {
                             writer.Write(actualProjectLockJson);
                         }
                     });
-                var actualPaths = resolver.ResolveNuGetPackage("A.B.C/1.2");
+                var actualPaths = resolver.ResolveNuGetPackage("A.B.C", "1.2");
                 AssertEx.SetEqual(actualPaths,
                     PathUtilities.CombineAbsoluteAndRelativePaths(packagesDirectory, PathUtilities.CombinePossiblyRelativeAndRelativePaths("System.Collections/4.0.10", "ref/dotnet/System.Collections.dll")),
                     PathUtilities.CombineAbsoluteAndRelativePaths(packagesDirectory, PathUtilities.CombinePossiblyRelativeAndRelativePaths("System.IO/4.0.10", "ref/dotnet/System.Runtime.dll")),
@@ -89,24 +115,34 @@ public void ResolveReference()
             }
         }
 
+        /// <summary>
+        /// Expected exception thrown during restore.
+        /// </summary>
         [ConditionalFact(typeof(WindowsOnly))]
         public void HandledException()
         {
             using (var directory = new DisposableDirectory(Temp))
             {
-                var resolver = new NuGetPackageResolverImpl(directory.Path, startInfo => { throw new IOException(); });
-                var actualPaths = resolver.ResolveNuGetPackage("A.B.C/1.2");
+                bool restored = false;
+                var resolver = new NuGetPackageResolverImpl(directory.Path, startInfo => { restored = true; throw new IOException(); });
+                var actualPaths = resolver.ResolveNuGetPackage("A.B.C", "1.2");
                 Assert.True(actualPaths.IsDefault);
+                Assert.True(restored);
             }
         }
 
+        /// <summary>
+        /// Unexpected exception thrown during restore.
+        /// </summary>
         [ConditionalFact(typeof(WindowsOnly))]
         public void UnhandledException()
         {
             using (var directory = new DisposableDirectory(Temp))
             {
-                var resolver = new NuGetPackageResolverImpl(directory.Path, startInfo => { throw new InvalidOperationException(); });
-                Assert.Throws<InvalidOperationException>(() => resolver.ResolveNuGetPackage("A.B.C/1.2"));
+                bool restored = false;
+                var resolver = new NuGetPackageResolverImpl(directory.Path, startInfo => { restored = true; throw new InvalidOperationException(); });
+                Assert.Throws<InvalidOperationException>(() => resolver.ResolveNuGetPackage("A.B.C", "1.2"));
+                Assert.True(restored);
             }
         }
 
@@ -114,24 +150,31 @@ public void UnhandledException()
         public void ParsePackageNameAndVersion()
         {
             ParseInvalidPackageReference("A");
-            ParseInvalidPackageReference("A.B");
-            ParseInvalidPackageReference("A/");
-            ParseInvalidPackageReference("A//1.0");
-            ParseInvalidPackageReference("/1.0.0");
-            ParseInvalidPackageReference("A/B/2.0.0");
+            ParseInvalidPackageReference("A/1");
+            ParseInvalidPackageReference("nuget");
+            ParseInvalidPackageReference("nuget:");
+            ParseInvalidPackageReference("NUGET:");
+            ParseInvalidPackageReference("nugetA/1");
+            ParseInvalidPackageReference("nuget:A");
+            ParseInvalidPackageReference("nuget:A.B");
+            ParseInvalidPackageReference("nuget:A/");
+            ParseInvalidPackageReference("nuget:A//1.0");
+            ParseInvalidPackageReference("nuget:/1.0.0");
+            ParseInvalidPackageReference("nuget:A/B/2.0.0");
 
-            ParseValidPackageReference("A/1", "A", "1");
-            ParseValidPackageReference("A.B/1.0.0", "A.B", "1.0.0");
-            ParseValidPackageReference("A/B.C", "A", "B.C");
-            ParseValidPackageReference("  /1", "  ", "1");
-            ParseValidPackageReference("A\t/\n1.0\r ", "A\t", "\n1.0\r ");
+            ParseValidPackageReference("nuget::nuget/1", ":nuget", "1");
+            ParseValidPackageReference("nuget:A/1", "A", "1");
+            ParseValidPackageReference("nuget:A.B/1.0.0", "A.B", "1.0.0");
+            ParseValidPackageReference("nuget:A/B.C", "A", "B.C");
+            ParseValidPackageReference("nuget:  /1", "  ", "1");
+            ParseValidPackageReference("nuget:A\t/\n1.0\r ", "A\t", "\n1.0\r ");
         }
 
         private static void ParseValidPackageReference(string reference, string expectedName, string expectedVersion)
         {
             string name;
             string version;
-            Assert.True(NuGetPackageResolverImpl.ParsePackageReference(reference, out name, out version));
+            Assert.True(NuGetPackageResolverImpl.TryParsePackageReference(reference, out name, out version));
             Assert.Equal(expectedName, name);
             Assert.Equal(expectedVersion, version);
         }
@@ -140,7 +183,7 @@ private static void ParseInvalidPackageReference(string reference)
         {
             string name;
             string version;
-            Assert.False(NuGetPackageResolverImpl.ParsePackageReference(reference, out name, out version));
+            Assert.False(NuGetPackageResolverImpl.TryParsePackageReference(reference, out name, out version));
             Assert.Null(name);
             Assert.Null(version);
         }

src/InteractiveWindow/Editor/BufferBlock.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.IO;
+using System.Runtime.Serialization;
+using System.Runtime.Serialization.Json;
+using System.Text;
+
+namespace Microsoft.VisualStudio.InteractiveWindow
+{
+    /// <summary>
+    /// REPL session buffer: input, output, or prompt.
+    /// </summary>
+    [DataContract]
+    internal struct BufferBlock
+    {
+        [DataMember(Name = "kind")]
+        internal readonly ReplSpanKind Kind;
+
+        [DataMember(Name = "content")]
+        internal readonly string Content;
+
+        internal BufferBlock(ReplSpanKind kind, string content)
+        {
+            Kind = kind;
+            Content = content;
+        }
+
+        internal static string Serialize(BufferBlock[] blocks)
+        {
+            var serializer = new DataContractJsonSerializer(typeof(BufferBlock[]));
+            using (var stream = new MemoryStream())
+            {
+                serializer.WriteObject(stream, blocks);
+                return Encoding.UTF8.GetString(stream.GetBuffer(), 0, (int)stream.Length);
+            }
+        }
+
+        internal static BufferBlock[] Deserialize(string str)
+        {
+            var serializer = new DataContractJsonSerializer(typeof(BufferBlock[]));
+            var bytes = Encoding.UTF8.GetBytes(str);
+            using (var stream = new MemoryStream(bytes))
+            {
+                var obj = serializer.ReadObject(stream);
+                return (BufferBlock[])obj;
+            }
+        }
+    }
+}

src/InteractiveWindow/Editor/InteractiveWindow.ReplSpanKind.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.Runtime.Serialization;
+
 namespace Microsoft.VisualStudio.InteractiveWindow
 {
-    internal partial class InteractiveWindow
+    [DataContract]
+    internal enum ReplSpanKind
     {
-        private enum ReplSpanKind
-        {
-            /// <summary>
-            /// Primary, secondary, or standard input prompt.
-            /// </summary>
-            Prompt,
+        /// <summary>
+        /// Primary, secondary, or standard input prompt.
+        /// </summary>
+        [EnumMember]
+        Prompt = 0,
 
-            /// <summary>
-            /// Line break inserted at end of output.
-            /// </summary>
-            LineBreak,
+        /// <summary>
+        /// The span represents output from the program (standard output).
+        /// </summary>
+        [EnumMember]
+        Output = 1,
 
-            /// <summary>
-            /// The span represents output from the program (standard output).
-            /// </summary>
-            Output,
+        /// <summary>
+        /// The span represents code inputted after a prompt or secondary prompt.
+        /// </summary>
+        [EnumMember]
+        Input = 2,
 
-            /// <summary>
-            /// The span represents code inputted after a prompt or secondary prompt.
-            /// </summary>
-            Language,
+        /// <summary>
+        /// The span represents the input for a standard input (non code input).
+        /// </summary>
+        [EnumMember]
+        StandardInput = 3,
 
-            /// <summary>
-            /// The span represents the input for a standard input (non code input).
-            /// </summary>
-            StandardInput,
-        }
+        /// <summary>
+        /// Line break inserted at end of output.
+        /// </summary>
+        [EnumMember]
+        LineBreak = 4,
     }
 }
\ No newline at end of file

src/InteractiveWindow/Editor/InteractiveWindow.UIThreadOnly.cs

@@ -213,7 +213,7 @@ public async Task<ExecutionResult> ResetAsync(bool initialize)
                     {
                         var snapshot = _projectionBuffer.CurrentSnapshot;
                         var spanCount = snapshot.SpanCount;
-                        Debug.Assert(GetSpanKind(snapshot.GetSourceSpan(spanCount - 1)) == ReplSpanKind.Language);
+                        Debug.Assert(GetSpanKind(snapshot.GetSourceSpan(spanCount - 1)) == ReplSpanKind.Input);
                         StoreUncommittedInput();
                         RemoveProjectionSpans(spanCount - 2, 2);
                         CurrentLanguageBuffer = null;
@@ -356,7 +356,7 @@ public async Task<TextReader> ReadStandardInputAsync()
                     {
                         var snapshot = _projectionBuffer.CurrentSnapshot;
                         var spanCount = snapshot.SpanCount;
-                        if (spanCount > 0 && GetSpanKind(snapshot.GetSourceSpan(spanCount - 1)) == ReplSpanKind.Language)
+                        if (spanCount > 0 && GetSpanKind(snapshot.GetSourceSpan(spanCount - 1)) == ReplSpanKind.Input)
                         {
                             // we need to remove our input prompt.
                             RemoveLastInputPrompt();
@@ -602,6 +602,22 @@ public bool Paste()
                 {
                     InsertCode(format);
                 }
+                else if (Clipboard.ContainsData(ClipboardFormat))
+                {
+                    var blocks = BufferBlock.Deserialize((string)Clipboard.GetData(ClipboardFormat));
+                    // Paste each block separately.
+                    foreach (var block in blocks)
+                    {
+                        switch (block.Kind)
+                        {
+                            case ReplSpanKind.Input:
+                            case ReplSpanKind.Output:
+                            case ReplSpanKind.StandardInput:
+                                InsertCode(block.Content);
+                                break;
+                        }
+                    }
+                }
                 else if (Clipboard.ContainsText())
                 {
                     InsertCode(Clipboard.GetText());
@@ -675,7 +691,7 @@ private void AppendInput(string text)
                 var snapshot = _projectionBuffer.CurrentSnapshot;
                 var spanCount = snapshot.SpanCount;
                 var inputSpan = snapshot.GetSourceSpan(spanCount - 1);
-                Debug.Assert(GetSpanKind(inputSpan) == ReplSpanKind.Language ||
+                Debug.Assert(GetSpanKind(inputSpan) == ReplSpanKind.Input ||
                     GetSpanKind(inputSpan) == ReplSpanKind.StandardInput);
 
                 var buffer = inputSpan.Snapshot.TextBuffer;
@@ -1112,7 +1128,7 @@ private ITextBuffer GetLanguageBuffer(SnapshotPoint point)
                 // Grab the span following the prompt (either language or standard input).
                 var projectionSpan = sourceSpans[promptIndex + 1];
                 var kind = GetSpanKind(projectionSpan);
-                if (kind != ReplSpanKind.Language)
+                if (kind != ReplSpanKind.Input)
                 {
                     Debug.Assert(kind == ReplSpanKind.StandardInput);
                     return null;
@@ -1579,7 +1595,7 @@ private int GetProjectionSpanIndexFromEditableBufferPosition(IProjectionSnapshot
                 // and ending at the end of the projection buffer, each language buffer projection is on a separate line:
                 //   [prompt)[language)...[prompt)[language)<end of projection buffer>
                 int result = projectionSpansCount - (surfaceSnapshot.LineCount - surfaceLineNumber) * SpansPerLineOfInput + 1;
-                Debug.Assert(GetSpanKind(surfaceSnapshot.GetSourceSpan(result)) == ReplSpanKind.Language);
+                Debug.Assert(GetSpanKind(surfaceSnapshot.GetSourceSpan(result)) == ReplSpanKind.Input);
                 return result;
             }
 
@@ -2071,11 +2087,11 @@ public void SelectAll()
                 var inputSnapshot = projectionSpan.Snapshot;
                 var kind = GetSpanKind(projectionSpan);
 
-                Debug.Assert(kind == ReplSpanKind.Language || kind == ReplSpanKind.StandardInput);
+                Debug.Assert(kind == ReplSpanKind.Input || kind == ReplSpanKind.StandardInput);
 
                 // Language input block is a projection of the entire snapshot;
                 // std input block is a projection of a single span:
-                SnapshotPoint inputBufferEnd = (kind == ReplSpanKind.Language) ?
+                SnapshotPoint inputBufferEnd = (kind == ReplSpanKind.Input) ?
                     new SnapshotPoint(inputSnapshot, inputSnapshot.Length) :
                     projectionSpan.End;
 
@@ -2441,17 +2457,45 @@ private static NormalizedSnapshotSpanCollection GetSelectionSpans(ITextView text
 
             private DataObject Copy(NormalizedSnapshotSpanCollection spans)
             {
-                var text = spans.Aggregate(new StringBuilder(), GetTextWithoutPrompts, b => b.ToString());
+                var text = GetText(spans);
+                var blocks = GetTextBlocks(spans);
                 var rtf = _rtfBuilderService.GenerateRtf(spans, TextView);
                 var data = new DataObject();
                 data.SetData(DataFormats.StringFormat, text);
                 data.SetData(DataFormats.Text, text);
                 data.SetData(DataFormats.UnicodeText, text);
                 data.SetData(DataFormats.Rtf, rtf);
+                data.SetData(ClipboardFormat, blocks);
                 return data;
             }
 
-            private StringBuilder GetTextWithoutPrompts(StringBuilder builder, SnapshotSpan span)
+            /// <summary>
+            /// Get the text of the given spans as a simple concatenated string.
+            /// </summary>
+            private static string GetText(NormalizedSnapshotSpanCollection spans)
+            {
+                var builder = new StringBuilder();
+                foreach (var span in spans)
+                {
+                    builder.Append(span.GetText());
+                }
+                return builder.ToString();
+            }
+
+            /// <summary>
+            /// Get the text of the given spans as a serialized BufferBlock[].
+            /// </summary>
+            private string GetTextBlocks(NormalizedSnapshotSpanCollection spans)
+            {
+                var blocks = new List<BufferBlock>();
+                foreach (var span in spans)
+                {
+                    GetTextBlocks(blocks, span);
+                }
+                return BufferBlock.Serialize(blocks.ToArray());
+            }
+
+            private void GetTextBlocks(List<BufferBlock> blocks, SnapshotSpan span)
             {
                 // Find the range of source spans that cover the span.
                 var sourceSpans = GetSourceSpans(span.Snapshot);
@@ -2462,7 +2506,6 @@ private StringBuilder GetTextWithoutPrompts(StringBuilder builder, SnapshotSpan
                     index--;
                 }
 
-                // Add the text for all non-prompt spans within the range.
                 for (; index < n; index++)
                 {
                     var sourceSpan = sourceSpans[index];
@@ -2470,28 +2513,29 @@ private StringBuilder GetTextWithoutPrompts(StringBuilder builder, SnapshotSpan
                     {
                         continue;
                     }
-                    if (!IsPrompt(sourceSpan))
+                    var sourceSnapshot = sourceSpan.Snapshot;
+                    var mappedSpans = TextView.BufferGraph.MapDownToBuffer(span, SpanTrackingMode.EdgeExclusive, sourceSnapshot.TextBuffer);
+                    bool added = false;
+                    foreach (var mappedSpan in mappedSpans)
                     {
-                        var sourceSnapshot = sourceSpan.Snapshot;
-                        var mappedSpans = TextView.BufferGraph.MapDownToBuffer(span, SpanTrackingMode.EdgeExclusive, sourceSnapshot.TextBuffer);
-                        bool added = false;
-                        foreach (var mappedSpan in mappedSpans)
+                        var intersection = sourceSpan.Span.Intersection(mappedSpan);
+                        if (intersection.HasValue && !intersection.Value.IsEmpty)
                         {
-                            var intersection = sourceSpan.Span.Intersection(mappedSpan);
-                            if (intersection.HasValue)
+                            var kind = GetSpanKind(span);
+                            if (kind == ReplSpanKind.LineBreak)
                             {
-                                builder.Append(sourceSnapshot.GetText(intersection.Value));
-                                added = true;
+                                kind = ReplSpanKind.Output;
                             }
+                            var content = sourceSnapshot.GetText(intersection.Value);
+                            blocks.Add(new BufferBlock(kind, content));
+                            added = true;
                         }
-                        if (!added)
-                        {
-                            break;
-                        }
+                    }
+                    if (!added)
+                    {
+                        break;
                     }
                 }
-
-                return builder;
             }
 
             /// <summary>Implements <see cref="IInteractiveWindowOperations.Backspace"/>.</summary>
@@ -2795,7 +2839,7 @@ private ReplSpanKind GetSpanKind(SnapshotSpan span)
                         ReplSpanKind.LineBreak :
                         ReplSpanKind.Prompt;
                 }
-                return ReplSpanKind.Language;
+                return ReplSpanKind.Input;
             }
 
             #region Output

src/InteractiveWindow/Editor/InteractiveWindow.cs

@@ -33,6 +33,8 @@ namespace Microsoft.VisualStudio.InteractiveWindow
     /// </summary>
     internal partial class InteractiveWindow : IInteractiveWindow, IInteractiveWindowOperations2
     {
+        internal const string ClipboardFormat = "89344A36-9821-495A-8255-99A63969F87D";
+
         public event EventHandler<SubmissionBufferAddedEventArgs> SubmissionBufferAdded;
 
         PropertyCollection IPropertyOwner.Properties { get; } = new PropertyCollection();

src/InteractiveWindow/Editor/InteractiveWindow.csproj

@@ -56,8 +56,7 @@
     <Reference Include="System" />
     <Reference Include="System.ComponentModel.Composition" />
     <Reference Include="System.Core" />
-    <Reference Include="System.Drawing" />
-    <Reference Include="System.Windows.Forms" />
+    <Reference Include="System.Runtime.Serialization" />
     <Reference Include="System.Xaml" />
     <Reference Include="System.XML" />
     <Reference Include="WindowsBase" />
@@ -66,6 +65,7 @@
     <Content Include="Resources\ReplToolBarImages.bmp" />
   </ItemGroup>
   <ItemGroup>
+    <Compile Include="BufferBlock.cs" />
     <Compile Include="Commands\CancelExecutionCommand.cs" />
     <Compile Include="Commands\ClearScreenCommand.cs" />
     <Compile Include="Commands\CommandClassifier.cs" />

src/InteractiveWindow/EditorTest/InteractiveWindowTests.cs

@@ -3,6 +3,7 @@
 using System;
 using System.Collections.Generic;
 using System.Linq;
+using System.Text;
 using System.Threading.Tasks;
 using System.Windows;
 using Microsoft.VisualStudio.InteractiveWindow.Commands;
@@ -586,7 +587,7 @@ public void CopyWithinInput()
             Window.InsertCode("1 + 2");
             Window.Operations.SelectAll();
             Window.Operations.Copy();
-            VerifyClipboardData("1 + 2");
+            VerifyClipboardData("1 + 2", "1 + 2", @"[{""content"":""1 + 2"",""kind"":2}]");
 
             // Shrink the selection.
             var selection = Window.TextView.Selection;
@@ -594,7 +595,7 @@ public void CopyWithinInput()
             selection.Select(new SnapshotSpan(span.Snapshot, span.Start + 1, span.Length - 2), isReversed: false);
 
             Window.Operations.Copy();
-            VerifyClipboardData(" + ");
+            VerifyClipboardData(" + ", " + ", @"[{""content"":"" + "",""kind"":2}]");
         }
 
         [Fact]
@@ -616,13 +617,14 @@ public void CopyInputAndOutput()
             Window.Operations.SelectAll();
             Window.Operations.SelectAll();
             Window.Operations.Copy();
-            VerifyClipboardData(@"foreach (var o in new[] { 1, 2, 3 })
-System.Console.WriteLine();
+            VerifyClipboardData(@"> foreach (var o in new[] { 1, 2, 3 })
+> System.Console.WriteLine();
 1
 2
 3
-",
-@"> foreach (var o in new[] \{ 1, 2, 3 \})\par > System.Console.WriteLine();\par 1\par 2\par 3\par > ");
+> ",
+@"> foreach (var o in new[] \{ 1, 2, 3 \})\par > System.Console.WriteLine();\par 1\par 2\par 3\par > ",
+@"[{""content"":""> "",""kind"":2},{""content"":""foreach (var o in new[] { 1, 2, 3 })\u000d\u000a"",""kind"":2},{""content"":""> "",""kind"":2},{""content"":""System.Console.WriteLine();\u000d\u000a"",""kind"":2},{""content"":""1\u000d\u000a2\u000d\u000a3\u000d\u000a"",""kind"":2},{""content"":""> "",""kind"":2}]");
 
             // Shrink the selection.
             var selection = Window.TextView.Selection;
@@ -631,11 +633,12 @@ public void CopyInputAndOutput()
 
             Window.Operations.Copy();
             VerifyClipboardData(@"oreach (var o in new[] { 1, 2, 3 })
-System.Console.WriteLine();
+> System.Console.WriteLine();
 1
 2
 3",
-@"oreach (var o in new[] \{ 1, 2, 3 \})\par > System.Console.WriteLine();\par 1\par 2\par 3");
+@"oreach (var o in new[] \{ 1, 2, 3 \})\par > System.Console.WriteLine();\par 1\par 2\par 3",
+@"[{""content"":""oreach (var o in new[] { 1, 2, 3 })\u000d\u000a"",""kind"":2},{""content"":""> "",""kind"":2},{""content"":""System.Console.WriteLine();\u000d\u000a"",""kind"":2},{""content"":""1\u000d\u000a2\u000d\u000a3"",""kind"":2}]");
         }
 
         [Fact]
@@ -662,7 +665,8 @@ public void CutWithinInput()
             VerifyClipboardData(
 @"each (var o in new[] { 1, 2, 3 })
 System.Console.WriteLine()",
-                expectedRtf: null);
+                expectedRtf: null,
+                expectedRepl: null);
         }
 
         [Fact]
@@ -684,7 +688,7 @@ public void CutInputAndOutput()
             Window.Operations.SelectAll();
             Window.Operations.SelectAll();
             Window.Operations.Cut();
-            VerifyClipboardData(null);
+            VerifyClipboardData(null, null, null);
         }
 
         /// <summary>
@@ -701,15 +705,15 @@ public void CopyNoSelection()
 @" 1
 
 2 ");
-            CopyNoSelectionAndVerify(0, 7, "s +\r\n", @"> s +\par ");
-            CopyNoSelectionAndVerify(7, 11, "\r\n", @"> \par ");
-            CopyNoSelectionAndVerify(11, 17, " t\r\n", @">  t\par ");
-            CopyNoSelectionAndVerify(17, 21, " 1\r\n", @" 1\par ");
-            CopyNoSelectionAndVerify(21, 23, "\r\n", @"\par ");
-            CopyNoSelectionAndVerify(23, 28, "2 ", "2 > ");
+            CopyNoSelectionAndVerify(0, 7, "> s +\r\n", @"> s +\par ", @"[{""content"":""> "",""kind"":2},{""content"":""s +\u000d\u000a"",""kind"":2}]");
+            CopyNoSelectionAndVerify(7, 11, "> \r\n", @"> \par ", @"[{""content"":""> "",""kind"":2},{""content"":""\u000d\u000a"",""kind"":2}]");
+            CopyNoSelectionAndVerify(11, 17, ">  t\r\n", @">  t\par ", @"[{""content"":""> "",""kind"":2},{""content"":"" t\u000d\u000a"",""kind"":2}]");
+            CopyNoSelectionAndVerify(17, 21, " 1\r\n", @" 1\par ", @"[{""content"":"" 1\u000d\u000a"",""kind"":2}]");
+            CopyNoSelectionAndVerify(21, 23, "\r\n", @"\par ", @"[{""content"":""\u000d\u000a"",""kind"":2}]");
+            CopyNoSelectionAndVerify(23, 28, "2 > ", "2 > ", @"[{""content"":""2 "",""kind"":2},{""content"":""> "",""kind"":2}]");
         }
 
-        private void CopyNoSelectionAndVerify(int start, int end, string expectedText, string expectedRtf)
+        private void CopyNoSelectionAndVerify(int start, int end, string expectedText, string expectedRtf, string expectedRepl)
         {
             var caret = Window.TextView.Caret;
             var snapshot = Window.TextView.TextBuffer.CurrentSnapshot;
@@ -718,7 +722,81 @@ private void CopyNoSelectionAndVerify(int start, int end, string expectedText, s
                 Clipboard.Clear();
                 caret.MoveTo(new SnapshotPoint(snapshot, i));
                 Window.Operations.Copy();
-                VerifyClipboardData(expectedText, expectedRtf);
+                VerifyClipboardData(expectedText, expectedRtf, expectedRepl);
+            }
+        }
+
+        [Fact]
+        public void Paste()
+        {
+            var blocks = new[]
+            {
+                new BufferBlock(ReplSpanKind.Output, "a\r\nbc"),
+                new BufferBlock(ReplSpanKind.Prompt, "> "),
+                new BufferBlock(ReplSpanKind.Prompt, "< "),
+                new BufferBlock(ReplSpanKind.Input, "12"),
+                new BufferBlock(ReplSpanKind.StandardInput, "3"),
+                new BufferBlock((ReplSpanKind)10, "xyz")
+            };
+
+            // Paste from text clipboard format.
+            CopyToClipboard(blocks, includeRepl: false);
+            Window.Operations.Paste();
+            var text = Window.TextView.TextBuffer.CurrentSnapshot.GetText();
+            Assert.Equal("> a\r\n> bc> < 123xyz", text);
+
+            Window.Operations.ClearView();
+            text = Window.TextView.TextBuffer.CurrentSnapshot.GetText();
+            Assert.Equal("> ", text);
+
+            // Paste from custom clipboard format.
+            CopyToClipboard(blocks, includeRepl: true);
+            Window.Operations.Paste();
+            text = Window.TextView.TextBuffer.CurrentSnapshot.GetText();
+            Assert.Equal("> a\r\n> bc123", text);
+        }
+
+        private static void CopyToClipboard(BufferBlock[] blocks, bool includeRepl)
+        {
+            Clipboard.Clear();
+            var data = new DataObject();
+            var builder = new StringBuilder();
+            foreach (var block in blocks)
+            {
+                builder.Append(block.Content);
+            }
+            var text = builder.ToString();
+            data.SetData(DataFormats.UnicodeText, text);
+            data.SetData(DataFormats.StringFormat, text);
+            if (includeRepl)
+            {
+                data.SetData(InteractiveWindow.ClipboardFormat, BufferBlock.Serialize(blocks));
+            }
+            Clipboard.SetDataObject(data, false);
+        }
+
+        [Fact]
+        public void JsonSerialization()
+        {
+            var expectedContent = new []
+            {
+                new BufferBlock(ReplSpanKind.Prompt, "> "),
+                new BufferBlock(ReplSpanKind.Input, "Hello"),
+                new BufferBlock(ReplSpanKind.Prompt, ". "),
+                new BufferBlock(ReplSpanKind.StandardInput, "world"),
+                new BufferBlock(ReplSpanKind.Output, "Hello world"),
+            };
+            var actualJson = BufferBlock.Serialize(expectedContent);
+            var expectedJson = @"[{""content"":""> "",""kind"":0},{""content"":""Hello"",""kind"":2},{""content"":"". "",""kind"":0},{""content"":""world"",""kind"":3},{""content"":""Hello world"",""kind"":1}]";
+            Assert.Equal(expectedJson, actualJson);
+            var actualContent = BufferBlock.Deserialize(actualJson);
+            Assert.Equal(expectedContent.Length, actualContent.Length);
+            for (int i = 0; i < expectedContent.Length; i++)
+            {
+                var expectedBuffer = expectedContent[i];
+                var actualBuffer = actualContent[i];
+                Assert.Equal(expectedBuffer.Kind, actualBuffer.Kind);
+                Assert.Equal(expectedBuffer.Content, actualBuffer.Content);
             }
         }
 
@@ -1051,7 +1129,7 @@ public void CutWithOutSelectionInReadOnlyArea()
             Assert.Equal("> 1\r\n1\r\n> 2", Window.TextView.TextBuffer.CurrentSnapshot.GetText());
             AssertCaretVirtualPosition(1, 1);
 
-            VerifyClipboardData(null);
+            VerifyClipboardData(null, null, null);
 
             // Cut() with caret in active prompt
             caret.MoveToNextCaretPosition();
@@ -1060,7 +1138,7 @@ public void CutWithOutSelectionInReadOnlyArea()
 
             Assert.Equal("> 1\r\n1\r\n> ", Window.TextView.TextBuffer.CurrentSnapshot.GetText());
             AssertCaretVirtualPosition(2, 2);
-            VerifyClipboardData("2", expectedRtf: null);
+            VerifyClipboardData("2", expectedRtf: null, expectedRepl: null);
         }
 
         [Fact]
@@ -1089,7 +1167,7 @@ public void CutWithSelectionInReadonlyArea()
 
             Task.Run(() => Window.Operations.Cut()).PumpingWait();
             Assert.Equal("> 1\r\n1\r\n> 23", Window.TextView.TextBuffer.CurrentSnapshot.GetText());
-            VerifyClipboardData(null);
+            VerifyClipboardData(null, null, null);
 
             // Cut() with selection in active prompt, no-op
             selection.Clear();
@@ -1102,7 +1180,7 @@ public void CutWithSelectionInReadonlyArea()
 
             Task.Run(() => Window.Operations.Cut()).PumpingWait();
             Assert.Equal("> 1\r\n1\r\n> 23", Window.TextView.TextBuffer.CurrentSnapshot.GetText());
-            VerifyClipboardData(null);
+            VerifyClipboardData(null, null, null);
 
             // Cut() with selection overlaps with editable buffer, 
             // Cut editable content and move caret to closest editable location 
@@ -1119,7 +1197,7 @@ public void CutWithSelectionInReadonlyArea()
             Task.Run(() => Window.Operations.Cut()).PumpingWait();
             Assert.Equal("> 1\r\n1\r\n> 3", Window.TextView.TextBuffer.CurrentSnapshot.GetText());
             AssertCaretVirtualPosition(2, 2);
-            VerifyClipboardData("2", expectedRtf: null);
+            VerifyClipboardData("2", expectedRtf: null, expectedRepl: null);
         }
 
         [Fact]
@@ -1136,7 +1214,7 @@ public void PasteWithOutSelectionInReadOnlyArea()
             Clipboard.Clear();
             Window.Operations.Home(true);
             Window.Operations.Copy();
-            VerifyClipboardData("2", @"\ansi{\fonttbl{\f0 Consolas;}}{\colortbl;\red0\green0\blue0;\red255\green255\blue255;}\f0 \fs24 \cf1 \cb2 \highlight2 2");
+            VerifyClipboardData("2", @"\ansi{\fonttbl{\f0 Consolas;}}{\colortbl;\red0\green0\blue0;\red255\green255\blue255;}\f0 \fs24 \cf1 \cb2 \highlight2 2", @"[{""content"":""2"",""kind"":2}]");
 
             // Paste() with caret in readonly area, no-op 
             Window.TextView.Selection.Clear();      
@@ -1173,7 +1251,7 @@ public void PasteWithSelectionInReadonlyArea()
             Clipboard.Clear();
             Window.Operations.Home(true);
             Window.Operations.Copy();
-            VerifyClipboardData("23", @"\ansi{\fonttbl{\f0 Consolas;}}{\colortbl;\red0\green0\blue0;\red255\green255\blue255;}\f0 \fs24 \cf1 \cb2 \highlight2 23");
+            VerifyClipboardData("23", @"\ansi{\fonttbl{\f0 Consolas;}}{\colortbl;\red0\green0\blue0;\red255\green255\blue255;}\f0 \fs24 \cf1 \cb2 \highlight2 23", @"[{""content"":""23"",""kind"":2}]");
 
 
             // Paste() with selection in readonly area, no-op  
@@ -1231,17 +1309,13 @@ private void Submit(string submission, string output)
             }
         }
 
-        private static void VerifyClipboardData(string expectedText)
-        {
-            VerifyClipboardData(expectedText, expectedText);
-        }
-
-        private static void VerifyClipboardData(string expectedText, string expectedRtf)
+        private static void VerifyClipboardData(string expectedText, string expectedRtf, string expectedRepl)
         {
             var data = Clipboard.GetDataObject();
             Assert.Equal(expectedText, data.GetData(DataFormats.StringFormat));
             Assert.Equal(expectedText, data.GetData(DataFormats.Text));
             Assert.Equal(expectedText, data.GetData(DataFormats.UnicodeText));
+            Assert.Equal(expectedRepl, (string)data.GetData(InteractiveWindow.ClipboardFormat));
             var actualRtf = (string)data.GetData(DataFormats.Rtf);
             if (expectedRtf == null)
             {

src/Scripting/Core/AssemblyLoader/InteractiveAssemblyLoader.cs

@@ -127,7 +127,7 @@ public InteractiveAssemblyLoader(MetadataShadowCopyProvider shadowCopyProvider =
         internal Assembly Load(Stream peStream, Stream pdbStream)
         {
             byte[] peImage = new byte[peStream.Length];
-            peStream.Read(peImage, 0, peImage.Length);
+            peStream.TryReadAll(peImage, 0, peImage.Length);
             var assembly = CorLightup.Desktop.LoadAssembly(peImage);
 
             RegisterDependency(assembly);

src/Scripting/Core/Resolvers/NuGetPackageResolver.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.Immutable;
 
 namespace Microsoft.CodeAnalysis.Scripting.Hosting
 {
     internal abstract class NuGetPackageResolver
     {
-        internal abstract ImmutableArray<string> ResolveNuGetPackage(string reference);
+        private const string ReferencePrefix = "nuget:";
+
+        /// <summary>
+        /// Syntax is "nuget:id/version".
+        /// </summary>
+        internal static bool TryParsePackageReference(string reference, out string name, out string version)
+        {
+            if (reference.StartsWith(ReferencePrefix, StringComparison.Ordinal))
+            {
+                var parts = reference.Substring(ReferencePrefix.Length).Split('/');
+                if ((parts.Length == 2) &&
+                    (parts[0].Length > 0) &&
+                    (parts[1].Length > 0))
+                {
+                    name = parts[0];
+                    version = parts[1];
+                    return true;
+                }
+            }
+            name = null;
+            version = null;
+            return false;
+        }
+
+        internal abstract ImmutableArray<string> ResolveNuGetPackage(string packageName, string packageVersion);
     }
 }

src/Scripting/Core/Resolvers/RuntimeMetadataReferenceResolver.cs

@@ -2,7 +2,7 @@
 
 using System;
 using System.Collections.Immutable;
-using System.IO;
+using System.Diagnostics;
 using Roslyn.Utilities;
 
 namespace Microsoft.CodeAnalysis.Scripting.Hosting
@@ -15,7 +15,7 @@ namespace Microsoft.CodeAnalysis.Scripting.Hosting
     /// </remarks>
     internal sealed class RuntimeMetadataReferenceResolver : MetadataReferenceResolver, IEquatable<RuntimeMetadataReferenceResolver>
     {
-        public static readonly RuntimeMetadataReferenceResolver Default = new RuntimeMetadataReferenceResolver();
+        public static readonly RuntimeMetadataReferenceResolver Default = new RuntimeMetadataReferenceResolver(ImmutableArray<string>.Empty, baseDirectory: null);
 
         internal readonly RelativePathResolver PathResolver;
         internal readonly NuGetPackageResolver PackageResolver;
@@ -23,8 +23,8 @@ internal sealed class RuntimeMetadataReferenceResolver : MetadataReferenceResolv
         private readonly Func<string, MetadataReferenceProperties, PortableExecutableReference> _fileReferenceProvider;
 
         internal RuntimeMetadataReferenceResolver(
-            ImmutableArray<string> searchPaths = default(ImmutableArray<string>),
-            string baseDirectory = null)
+            ImmutableArray<string> searchPaths,
+            string baseDirectory)
             : this(new RelativePathResolver(searchPaths.NullToEmpty(), baseDirectory),
                    null,
                    GacFileResolver.Default)
@@ -46,27 +46,29 @@ internal sealed class RuntimeMetadataReferenceResolver : MetadataReferenceResolv
 
         public override ImmutableArray<PortableExecutableReference> ResolveReference(string reference, string baseFilePath, MetadataReferenceProperties properties)
         {
-            if (PathResolver != null && PathUtilities.IsFilePath(reference))
+            string packageName;
+            string packageVersion;
+            if (NuGetPackageResolver.TryParsePackageReference(reference, out packageName, out packageVersion))
             {
-                var resolvedPath = PathResolver.ResolvePath(reference, baseFilePath);
-                if (resolvedPath == null)
+                if (PackageResolver != null)
                 {
-                    return ImmutableArray<PortableExecutableReference>.Empty;
+                    var paths = PackageResolver.ResolveNuGetPackage(packageName, packageVersion);
+                    Debug.Assert(!paths.IsDefault);
+                    return paths.SelectAsArray(path => _fileReferenceProvider(path, properties));
                 }
-
-                return ImmutableArray.Create(_fileReferenceProvider(resolvedPath, properties));
             }
-
-            if (PackageResolver != null)
+            else if (PathUtilities.IsFilePath(reference))
             {
-                var paths = PackageResolver.ResolveNuGetPackage(reference);
-                if (!paths.IsDefaultOrEmpty)
+                if (PathResolver != null)
                 {
-                    return paths.SelectAsArray(path => _fileReferenceProvider(path, properties));
+                    var resolvedPath = PathResolver.ResolvePath(reference, baseFilePath);
+                    if (resolvedPath != null)
+                    {
+                        return ImmutableArray.Create(_fileReferenceProvider(resolvedPath, properties));
+                    }
                 }
             }
-
-            if (GacFileResolver != null)
+            else if (GacFileResolver != null)
             {
                 var path = GacFileResolver.Resolve(reference);
                 if (path != null)
@@ -74,7 +76,6 @@ public override ImmutableArray<PortableExecutableReference> ResolveReference(str
                     return ImmutableArray.Create(_fileReferenceProvider(path, properties));
                 }
             }
-
             return ImmutableArray<PortableExecutableReference>.Empty;
         }
 

src/Scripting/Core/ScriptOptions.cs

@@ -340,7 +340,9 @@ private static ImmutableArray<T> CheckImmutableArray<T>(ImmutableArray<T> items,
         private static ImmutableArray<T> ToImmutableArrayChecked<T>(IEnumerable<T> items, string parameterName)
             where T : class
         {
-            return AddRangeAndFreeChecked(ArrayBuilder<T>.GetInstance(), items, parameterName);
+            var builder = ArrayBuilder<T>.GetInstance();
+            AddRangeChecked(builder, items, parameterName);
+            return builder.ToImmutableAndFree();
         }
 
         private static ImmutableArray<T> ConcatChecked<T>(ImmutableArray<T> existing, IEnumerable<T> items, string parameterName)
@@ -348,10 +350,11 @@ private static ImmutableArray<T> ConcatChecked<T>(ImmutableArray<T> existing, IE
         {
             var builder = ArrayBuilder<T>.GetInstance();
             builder.AddRange(existing);
-            return AddRangeAndFreeChecked(builder, items, parameterName);
+            AddRangeChecked(builder, items, parameterName);
+            return builder.ToImmutableAndFree();
         }
 
-        private static ImmutableArray<T> AddRangeAndFreeChecked<T>(ArrayBuilder<T> builder, IEnumerable<T> items, string parameterName)
+        private static void AddRangeChecked<T>(ArrayBuilder<T> builder, IEnumerable<T> items, string parameterName)
             where T : class
         {
             RequireNonNull(items, parameterName);
@@ -360,14 +363,11 @@ private static ImmutableArray<T> AddRangeAndFreeChecked<T>(ArrayBuilder<T> build
             {
                 if (item == null)
                 {
-                    builder.Free();
                     throw new ArgumentNullException($"{parameterName}[{builder.Count}]");
                 }
 
                 builder.Add(item);
             }
-
-            return builder.ToImmutableAndFree();
         }
 
         private static IEnumerable<S> SelectChecked<T, S>(IEnumerable<T> items, string parameterName, Func<T, S> selector)

src/Scripting/CoreTest/RuntimeMetadataReferenceResolverTests.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.Scripting.Hosting;
+using Microsoft.CodeAnalysis.Test.Utilities;
+using Roslyn.Test.Utilities;
+using System.Collections.Immutable;
+using Xunit;
+
+namespace Microsoft.CodeAnalysis.UnitTests.Interactive
+{
+    public class RuntimeMetadataReferenceResolverTests : TestBase
+    {
+        [Fact]
+        public void Resolve()
+        {
+            using (var directory = new DisposableDirectory(Temp))
+            {
+                var assembly1 = directory.CreateFile("_1.dll");
+                var assembly2 = directory.CreateFile("_2.dll");
+
+                // With NuGetPackageResolver.
+                var resolver = new RuntimeMetadataReferenceResolver(
+                    new RelativePathResolver(ImmutableArray.Create(directory.Path), baseDirectory: directory.Path),
+                    new PackageResolver(ImmutableDictionary<string, ImmutableArray<string>>.Empty.Add("nuget:N/1.0", ImmutableArray.Create(assembly1.Path, assembly2.Path))),
+                    gacFileResolver: null);
+                // Recognized NuGet reference.
+                var actualReferences = resolver.ResolveReference("nuget:N/1.0", baseFilePath: null, properties: MetadataReferenceProperties.Assembly);
+                AssertEx.SetEqual(actualReferences.SelectAsArray(r => r.FilePath), assembly1.Path, assembly2.Path);
+                // Unrecognized NuGet reference.
+                actualReferences = resolver.ResolveReference("nuget:N/2.0", baseFilePath: null, properties: MetadataReferenceProperties.Assembly);
+                Assert.True(actualReferences.IsEmpty);
+                // Recognized file path. 
+                actualReferences = resolver.ResolveReference("_2.dll", baseFilePath: null, properties: MetadataReferenceProperties.Assembly);
+                AssertEx.SetEqual(actualReferences.SelectAsArray(r => r.FilePath), assembly2.Path);
+                // Unrecognized file path. 
+                actualReferences = resolver.ResolveReference("_3.dll", baseFilePath: null, properties: MetadataReferenceProperties.Assembly);
+                Assert.True(actualReferences.IsEmpty);
+
+                // Without NuGetPackageResolver.
+                resolver = new RuntimeMetadataReferenceResolver(
+                    new RelativePathResolver(ImmutableArray.Create(directory.Path), baseDirectory: directory.Path),
+                    packageResolver: null,
+                    gacFileResolver: null);
+                // Unrecognized NuGet reference.
+                actualReferences = resolver.ResolveReference("nuget:N/1.0", baseFilePath: null, properties: MetadataReferenceProperties.Assembly);
+                Assert.True(actualReferences.IsEmpty);
+                // Recognized file path. 
+                actualReferences = resolver.ResolveReference("_2.dll", baseFilePath: null, properties: MetadataReferenceProperties.Assembly);
+                AssertEx.SetEqual(actualReferences.SelectAsArray(r => r.FilePath), assembly2.Path);
+                // Unrecognized file path. 
+                actualReferences = resolver.ResolveReference("_3.dll", baseFilePath: null, properties: MetadataReferenceProperties.Assembly);
+                Assert.True(actualReferences.IsEmpty);
+            }
+        }
+
+        private sealed class PackageResolver : NuGetPackageResolver
+        {
+            private const string Prefix = "nuget:";
+            private readonly IImmutableDictionary<string, ImmutableArray<string>> _map;
+
+            internal PackageResolver(IImmutableDictionary<string, ImmutableArray<string>> map)
+            {
+                _map = map;
+            }
+
+            internal override ImmutableArray<string> ResolveNuGetPackage(string packageName, string packageVersion)
+            {
+                var reference = $"{Prefix}{packageName}/{packageVersion}";
+                ImmutableArray<string> paths;
+                if (_map.TryGetValue(reference, out paths))
+                {
+                    return paths;
+                }
+                return ImmutableArray<string>.Empty;
+            }
+        }
+    }
+}

src/Scripting/CoreTest/ScriptingTest.csproj

@@ -59,6 +59,7 @@
     <Compile Include="ObjectFormatterTestBase.cs" />
     <Compile Include="ObjectFormatterTests.Fixtures.cs" />
     <Compile Include="RedirectedOutput.cs" />
+    <Compile Include="RuntimeMetadataReferenceResolverTests.cs" />
     <Compile Include="ScriptingTestHelpers.cs" />
     <Compile Include="ScriptOptionsTests.cs" />
     <Compile Include="ScriptTaskExtensions.cs" />

src/Test/PdbUtilities/PdbUtilities.csproj

@@ -70,6 +70,9 @@
     <Compile Include="..\..\Compilers\Core\Portable\InternalUtilities\Hash.cs">
       <Link>InternalUtilities\Hash.cs</Link>
     </Compile>
+    <Compile Include="..\..\Compilers\Core\Portable\InternalUtilities\StreamExtensions.cs">
+      <Link>InternalUtilities\StreamExtensions.cs</Link>
+    </Compile>
     <Compile Include="..\..\Compilers\Core\Portable\PEWriter\CustomDebugInfoConstants.cs">
       <Link>Shared\CustomDebugInfoConstants.cs</Link>
     </Compile>

src/Workspaces/Core/Desktop/Workspaces.Desktop.csproj

@@ -46,6 +46,9 @@
     <Compile Include="..\..\..\Compilers\Core\Portable\EncodedStringText.cs">
       <Link>InternalUtilities\EncodedStringText.cs</Link>
     </Compile>
+    <Compile Include="..\..\..\Compilers\Core\Portable\InternalUtilities\StreamExtensions.cs">
+      <Link>InternalUtilities\StreamExtensions.cs</Link>
+    </Compile>
     <Compile Include="..\..\..\Compilers\Helpers\CoreClrShim.cs">
       <Link>InternalUtilities\CoreClrShim.cs</Link>
     </Compile>

src/Workspaces/Core/Portable/Log/FunctionId.cs

@@ -310,5 +310,6 @@ internal enum FunctionId
         VisualBasic_Interactive_Window,
 
         NonFatalWatson,
+        GlobalOperationRegistration,
     }
 }

src/Workspaces/Core/Portable/Notification/GlobalOperationRegistration.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.Threading;
+using Microsoft.CodeAnalysis.Internal.Log;
 
 namespace Microsoft.CodeAnalysis.Notification
 {
     internal class GlobalOperationRegistration : IDisposable
     {
         private readonly AbstractGlobalOperationNotificationService _service;
+        private readonly CancellationTokenSource _source;
+        private readonly IDisposable _logging;
+
         private bool _done;
 
         public GlobalOperationRegistration(AbstractGlobalOperationNotificationService service, string operation)
         {
             _service = service;
-            this.Operation = operation;
             _done = false;
+            this.Operation = operation;
+
+            _source = new CancellationTokenSource();
+            _logging = Logger.LogBlock(FunctionId.GlobalOperationRegistration, operation, _source.Token);
         }
 
         public string Operation { get; }
@@ -28,10 +36,15 @@ public void Dispose()
             if (_done)
             {
                 _service.Done(this);
+
+                _logging.Dispose();
             }
             else
             {
                 _service.Cancel(this);
+
+                _source.Cancel();
+                _logging.Dispose();
             }
         }
     }

src/Workspaces/Core/Portable/Workspace/Solution/Document.cs

@@ -61,7 +61,8 @@ public SourceCodeKind SourceCodeKind
 
         /// <summary>
         /// Get the current syntax tree for the document if the text is already loaded and the tree is already parsed.
-        /// Returns true if the syntax tree is already available, or false if getting the syntax tree would have incurred additional work.
+        /// In almost all cases, you should call <see cref="GetSyntaxTreeAsync"/> to fetch the tree, which will parse the tree
+        /// if it's not already parsed.
         /// </summary>
         public bool TryGetSyntaxTree(out SyntaxTree syntaxTree)
         {
@@ -88,7 +89,8 @@ public bool TryGetSyntaxTree(out SyntaxTree syntaxTree)
 
         /// <summary>
         /// Get the current syntax tree version for the document if the text is already loaded and the tree is already parsed.
-        /// Returns true if the syntax tree is already available, or false if getting the syntax tree would have incurred additional work.
+        /// In almost all cases, you should call <see cref="GetSyntaxVersionAsync"/> to fetch the version, which will load the tree
+        /// if it's not already available.
         /// </summary>
         public bool TryGetSyntaxVersion(out VersionStamp version)
         {
@@ -199,7 +201,9 @@ public Task<SyntaxTree> GetSyntaxTreeAsync(CancellationToken cancellationToken =
         }
 
         /// <summary>
-        /// Gets the root node of the current syntax tree if it is available.
+        /// Gets the root node of the current syntax tree if the syntax tree has already been parsed and the tree is still cached.
+        /// In almost all cases, you should call <see cref="GetSyntaxRootAsync"/> to fetch the root node, which will parse
+        /// the document if necessary.
         /// </summary>
         public bool TryGetSyntaxRoot(out SyntaxNode root)
         {
@@ -223,7 +227,9 @@ public async Task<SyntaxNode> GetSyntaxRootAsync(CancellationToken cancellationT
         }
 
         /// <summary>
-        /// Gets the current semantic model for this document if the model is already computed.
+        /// Gets the current semantic model for this document if the model is already computed and still cached.
+        /// In almost all cases, you should call <see cref="GetSemanticModelAsync"/>, which will compute the semantic model
+        /// if necessary.
         /// </summary>
         public bool TryGetSemanticModel(out SemanticModel semanticModel)
         {

src/Workspaces/Core/Portable/Workspace/Solution/Project.cs

@@ -372,7 +372,9 @@ private static TextDocument CreateAdditionalDocument(DocumentId documentId, Proj
         }
 
         /// <summary>
-        /// Get the <see cref="Compilation"/> for this project if it is available.
+        /// Tries to get the cached <see cref="Compilation"/> for this project if it has already been created and is still cached. In almost all
+        /// cases you should call <see cref="GetCompilationAsync"/> which will either return the cached <see cref="Compilation"/>
+        /// or create a new one otherwise.
         /// </summary>
         public bool TryGetCompilation(out Compilation compilation)
         {