Merge branch 'master' of https://github.com/dotnet/roslyn into oop2

Compilers.sln

 
 Microsoft Visual Studio Solution File, Format Version 12.00
 # Visual Studio 14
-VisualStudioVersion = 14.0.25123.0
+VisualStudioVersion = 14.0.24720.0
 MinimumVisualStudioVersion = 10.0.40219.1
 Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "CodeAnalysisTest", "src\Compilers\Core\CodeAnalysisTest\CodeAnalysisTest.csproj", "{A4C99B85-765C-4C65-9C2A-BB609AAB09E6}"
 EndProject
@@ -135,22 +135,22 @@ Global
 		src\Test\Utilities\Shared\TestUtilities.projitems*{6ff42825-5464-4151-ac55-ed828168c192}*SharedItemsImports = 13
 		src\Compilers\Core\CommandLine\CommandLine.projitems*{ad6f474e-e6d4-4217-91f3-b7af1be31ccc}*SharedItemsImports = 13
 		src\Compilers\Core\AnalyzerDriver\AnalyzerDriver.projitems*{d0bc9be7-24f6-40ca-8dc6-fcb93bd44b34}*SharedItemsImports = 13
-		src\Compilers\Server\ServerShared\ServerShared.projitems*{06b26dcb-7a12-48ef-ae50-708593abd05f}*SharedItemsImports = 4
 		src\Compilers\Core\CommandLine\CommandLine.projitems*{06b26dcb-7a12-48ef-ae50-708593abd05f}*SharedItemsImports = 4
+		src\Compilers\Server\ServerShared\ServerShared.projitems*{06b26dcb-7a12-48ef-ae50-708593abd05f}*SharedItemsImports = 4
 		src\Compilers\Core\CommandLine\CommandLine.projitems*{e58ee9d7-1239-4961-a0c1-f9ec3952c4c1}*SharedItemsImports = 4
-		src\Compilers\Server\ServerShared\ServerShared.projitems*{9508f118-f62e-4c16-a6f4-7c3b56e166ad}*SharedItemsImports = 4
 		src\Compilers\Core\CommandLine\CommandLine.projitems*{9508f118-f62e-4c16-a6f4-7c3b56e166ad}*SharedItemsImports = 4
+		src\Compilers\Server\ServerShared\ServerShared.projitems*{9508f118-f62e-4c16-a6f4-7c3b56e166ad}*SharedItemsImports = 4
 		src\Compilers\Core\SharedCollections\SharedCollections.projitems*{afde6bea-5038-4a4a-a88e-dbd2e4088eed}*SharedItemsImports = 4
-		src\Compilers\Core\AnalyzerDriver\AnalyzerDriver.projitems*{1ee8cad3-55f9-4d91-96b2-084641da9a6c}*SharedItemsImports = 4
 		src\Compilers\Core\SharedCollections\SharedCollections.projitems*{1ee8cad3-55f9-4d91-96b2-084641da9a6c}*SharedItemsImports = 4
-		src\Compilers\Core\MSBuildTask\Shared\MSBuildTask.Shared.projitems*{7ad4fe65-9a30-41a6-8004-aa8f89bcb7f3}*SharedItemsImports = 4
+		src\Compilers\Core\AnalyzerDriver\AnalyzerDriver.projitems*{1ee8cad3-55f9-4d91-96b2-084641da9a6c}*SharedItemsImports = 4
 		src\Compilers\Core\CommandLine\CommandLine.projitems*{7ad4fe65-9a30-41a6-8004-aa8f89bcb7f3}*SharedItemsImports = 4
+		src\Compilers\Core\MSBuildTask\Shared\MSBuildTask.Shared.projitems*{7ad4fe65-9a30-41a6-8004-aa8f89bcb7f3}*SharedItemsImports = 4
 		src\Compilers\CSharp\CSharpAnalyzerDriver\CSharpAnalyzerDriver.projitems*{b501a547-c911-4a05-ac6e-274a50dff30e}*SharedItemsImports = 4
 		src\Compilers\VisualBasic\BasicAnalyzerDriver\BasicAnalyzerDriver.projitems*{2523d0e6-df32-4a3e-8ae0-a19bffae2ef6}*SharedItemsImports = 4
 		src\Compilers\Core\CommandLine\CommandLine.projitems*{4b45ca0c-03a0-400f-b454-3d4bcb16af38}*SharedItemsImports = 4
 		src\Compilers\Core\SharedCollections\SharedCollections.projitems*{c1930979-c824-496b-a630-70f5369a636f}*SharedItemsImports = 13
-		src\Compilers\Core\MSBuildTask\Shared\MSBuildTask.Shared.projitems*{d874349c-8bb3-4bdc-8535-2d52ccca1198}*SharedItemsImports = 4
 		src\Compilers\Core\CommandLine\CommandLine.projitems*{d874349c-8bb3-4bdc-8535-2d52ccca1198}*SharedItemsImports = 4
+		src\Compilers\Core\MSBuildTask\Shared\MSBuildTask.Shared.projitems*{d874349c-8bb3-4bdc-8535-2d52ccca1198}*SharedItemsImports = 4
 		src\Compilers\Core\CommandLine\CommandLine.projitems*{e3cd2895-76a8-4d11-a316-ea67cb5ea42c}*SharedItemsImports = 4
 	EndGlobalSection
 	GlobalSection(SolutionConfigurationPlatforms) = preSolution

src/EditorFeatures/Core/Implementation/IntelliSense/Completion/CompletionProviders/AbstractMemberInsertingCompletionProvider.cs

@@ -2,6 +2,7 @@
 
 using System.Linq;
 using System.Threading;
+using System.Threading.Tasks;
 using Microsoft.CodeAnalysis.CodeGeneration;
 using Microsoft.CodeAnalysis.Completion;
 using Microsoft.CodeAnalysis.Editing;
@@ -25,7 +26,7 @@ internal abstract class AbstractMemberInsertingCompletionProvider : CompletionLi
 
         protected abstract SyntaxToken GetToken(MemberInsertionCompletionItem completionItem, SyntaxTree tree, CancellationToken cancellationToken);
 
-        protected abstract ISymbol GenerateMember(ISymbol member, INamedTypeSymbol containingType, Document document, MemberInsertionCompletionItem item, CancellationToken cancellationToken);
+        protected abstract Task<ISymbol> GenerateMemberAsync(ISymbol member, INamedTypeSymbol containingType, Document document, MemberInsertionCompletionItem item, CancellationToken cancellationToken);
         protected abstract int GetTargetCaretPosition(SyntaxNode caretTarget);
         protected abstract SyntaxNode GetSyntax(SyntaxToken commonSyntaxToken);
 
@@ -44,12 +45,13 @@ public void Commit(CompletionItem completionItem, ITextView textView, ITextBuffe
                 allowCancel: true,
                 action: c =>
             {
-                var newDocument = DetermineNewDocument((MemberInsertionCompletionItem)completionItem, currentSnapshot, c.CancellationToken);
+                var cancellationToken = c.CancellationToken;
+                var newDocument = DetermineNewDocumentAsync((MemberInsertionCompletionItem)completionItem, currentSnapshot, cancellationToken).WaitAndGetResult(cancellationToken);
 
                 // Apply the new document to workspace
-                newDocument.Project.Solution.Workspace.ApplyDocumentChanges(newDocument, c.CancellationToken);
+                newDocument.Project.Solution.Workspace.ApplyDocumentChanges(newDocument, cancellationToken);
 
-                var newRoot = newDocument.GetSyntaxRootAsync(c.CancellationToken).WaitAndGetResult(c.CancellationToken);
+                var newRoot = newDocument.GetSyntaxRootAsync(cancellationToken).WaitAndGetResult(cancellationToken);
 
                 // Attempt to find the inserted node and move the caret appropriately
                 if (newRoot != null)
@@ -74,7 +76,7 @@ public void Commit(CompletionItem completionItem, ITextView textView, ITextBuffe
             });
         }
 
-        private Document DetermineNewDocument(MemberInsertionCompletionItem completionItem, ITextSnapshot textSnapshot, CancellationToken cancellationToken)
+        private async Task<Document> DetermineNewDocumentAsync(MemberInsertionCompletionItem completionItem, ITextSnapshot textSnapshot, CancellationToken cancellationToken)
         {
             // The span we're going to replace
             var line = textSnapshot.GetLineFromLineNumber(completionItem.Line);
@@ -89,7 +91,7 @@ private Document DetermineNewDocument(MemberInsertionCompletionItem completionIt
             var annotatedRoot = tree.GetRoot(cancellationToken).ReplaceToken(token, token.WithAdditionalAnnotations(_otherAnnotation));
             document = document.WithSyntaxRoot(annotatedRoot);
 
-            Document memberContainingDocument = GenerateMemberAndUsings(document, completionItem, line, cancellationToken);
+            var memberContainingDocument = await GenerateMemberAndUsingsAsync(document, completionItem, line, cancellationToken).ConfigureAwait(false);
 
             var insertionRoot = PrepareTreeForMemberInsertion(memberContainingDocument, cancellationToken);
             var insertionText = GenerateInsertionText(memberContainingDocument, cancellationToken);
@@ -106,7 +108,7 @@ private Document DetermineNewDocument(MemberInsertionCompletionItem completionIt
             return Formatter.FormatAsync(document, _annotation, cancellationToken: cancellationToken).WaitAndGetResult(cancellationToken);
         }
 
-        private Document GenerateMemberAndUsings(
+        private async Task<Document> GenerateMemberAndUsingsAsync(
             Document document,
             MemberInsertionCompletionItem completionItem,
             ITextSnapshotLine line,
@@ -124,7 +126,7 @@ private Document DetermineNewDocument(MemberInsertionCompletionItem completionIt
             // CodeGenerationOptions containing before and after
             var options = new CodeGenerationOptions(contextLocation: semanticModel.SyntaxTree.GetLocation(TextSpan.FromBounds(line.Start, line.Start)));
 
-            var generatedMember = GenerateMember(overriddenMember, containingType, document, completionItem, cancellationToken);
+            var generatedMember = await GenerateMemberAsync(overriddenMember, containingType, document, completionItem, cancellationToken).ConfigureAwait(false);
             generatedMember = _annotation.AddAnnotationToSymbol(generatedMember);
 
             Document memberContainingDocument = null;

src/EditorFeatures/Core/Implementation/IntelliSense/Completion/CompletionProviders/AbstractOverrideCompletionProvider.cs

@@ -41,7 +41,7 @@ public override async Task ProduceCompletionListAsync(CompletionListContext cont
             }
         }
 
-        protected override ISymbol GenerateMember(ISymbol newOverriddenMember, INamedTypeSymbol newContainingType, Document newDocument, MemberInsertionCompletionItem completionItem, CancellationToken cancellationToken)
+        protected override async Task<ISymbol> GenerateMemberAsync(ISymbol newOverriddenMember, INamedTypeSymbol newContainingType, Document newDocument, MemberInsertionCompletionItem completionItem, CancellationToken cancellationToken)
         {
             // Figure out what to insert, and do it. Throw if we've somehow managed to get this far and can't.
             var syntaxFactory = newDocument.GetLanguageService<SyntaxGenerator>();
@@ -50,13 +50,13 @@ protected override ISymbol GenerateMember(ISymbol newOverriddenMember, INamedTyp
             var modifiers = completionItem.Modifiers.WithIsUnsafe(completionItem.Modifiers.IsUnsafe | newOverriddenMember.IsUnsafe());
             if (newOverriddenMember.Kind == SymbolKind.Method)
             {
-                return syntaxFactory.OverrideMethod((IMethodSymbol)newOverriddenMember,
-                    modifiers, newContainingType, newDocument, cancellationToken);
+                return await syntaxFactory.OverrideMethodAsync((IMethodSymbol)newOverriddenMember,
+                    modifiers, newContainingType, newDocument, cancellationToken).ConfigureAwait(false);
             }
             else if (newOverriddenMember.Kind == SymbolKind.Property)
             {
-                return syntaxFactory.OverrideProperty((IPropertySymbol)newOverriddenMember,
-                    modifiers, newContainingType, newDocument, cancellationToken);
+                return await syntaxFactory.OverridePropertyAsync((IPropertySymbol)newOverriddenMember,
+                    modifiers, newContainingType, newDocument, cancellationToken).ConfigureAwait(false);
             }
             else
             {

src/EditorFeatures/Core/Implementation/IntelliSense/Completion/CompletionProviders/AbstractPartialCompletionProvider.cs

@@ -63,10 +63,10 @@ public override async Task ProduceCompletionListAsync(CompletionListContext cont
             }
         }
 
-        protected override ISymbol GenerateMember(ISymbol member, INamedTypeSymbol containingType, Document document, MemberInsertionCompletionItem item, CancellationToken cancellationToken)
+        protected override async Task<ISymbol> GenerateMemberAsync(ISymbol member, INamedTypeSymbol containingType, Document document, MemberInsertionCompletionItem item, CancellationToken cancellationToken)
         {
             var syntaxFactory = document.GetLanguageService<SyntaxGenerator>();
-            var semanticModel = document.GetSemanticModelAsync(cancellationToken).WaitAndGetResult(cancellationToken);
+            var semanticModel = await document.GetSemanticModelAsync(cancellationToken).ConfigureAwait(false);
 
             return CodeGenerationSymbolFactory.CreateMethodSymbol(attributes: new List<AttributeData>(),
                 accessibility: Accessibility.NotApplicable,

src/Test/Perf/infra/automation.csx

@@ -14,8 +14,5 @@ ShellOutVital(Path.Combine(directoryUtil.RoslynDirectory, "Restore.cmd"), "", wo
 // Build Roslyn in Release Mode
 ShellOutVital("msbuild", "./Roslyn.sln /p:Configuration=Release", workingDirectory: directoryUtil.RoslynDirectory);
 
-// Run DownloadTools before using the TraceManager because TraceManager uses the downloaded CPC binaries
-DownloadTools();
-
 // Run run_and_report.csx
 await RunFile(Path.Combine(directoryUtil.MyWorkingDirectory, "run_and_report.csx"));

src/Test/Perf/runner.csx

@@ -9,7 +9,7 @@ using System.IO;
 using System;
 
 var directoryInfo = new RelativeDirectory();
-var testDirectory = Path.Combine(directoryInfo.MyWorkingDirectory, "Tests");
+var testDirectory = Path.Combine(directoryInfo.MyWorkingDirectory, "tests");
 
 // Print message at startup
 Log("Starting Performance Test Run");
@@ -29,45 +29,31 @@ foreach (var script in GetAllCsxRecursive(testDirectory))
 }
 
 var traceManager = TraceManagerFactory.GetTraceManager();
-traceManager.Setup();
-for (int i = 0; i < traceManager.Iterations; i++)
-{
-    traceManager.Start();
-    foreach (dynamic test in testInstances)
-    {
-        test.Setup();
-        traceManager.StartScenario(test.Name, test.MeasuredProc);
-        traceManager.StartEvent();
-        test.Test();
-        traceManager.EndEvent();
-        traceManager.EndScenario();
-    }
-    traceManager.EndScenarios();
-    traceManager.WriteScenariosFileToDisk();
-    traceManager.Stop();
-    traceManager.ResetScenarioGenerator();
-}
-traceManager.Cleanup();
-
-/*
-var traceManager = TraceManagerFactory.GetTraceManager();
-traceManager.Setup();
-// Run each of the tests
-foreach (dynamic test in testInstances) 
+traceManager.Initialize();
+foreach (dynamic test in testInstances)
 {
     test.Setup();
-    traceManager.Start();
-    for (int i = 0; i < test.Iterations; i++) 
+    traceManager.Setup();
+    
+    var iterations = traceManager.HasWarmUpIteration ? 
+                     test.Iterations + 1 :
+                     test.Iterations;
+                     
+    for (int i = 0; i < iterations; i++)
     {
-        traceManager.StartScenario("temp" + i, "csc");
+        traceManager.StartScenarios();
+        traceManager.Start();
+        traceManager.StartScenario(test.Name + i, test.MeasuredProc);
         traceManager.StartEvent();
         test.Test();
         traceManager.EndEvent();
         traceManager.EndScenario();
+        
+        traceManager.EndScenarios();
+        traceManager.WriteScenariosFileToDisk();
+        traceManager.Stop();
+        traceManager.ResetScenarioGenerator();
     }
-    traceManager.EndScenarios();
-    traceManager.WriteScenariosFileToDisk();
-    traceManager.Stop();
+
     traceManager.Cleanup();
 }
-*/

src/Test/Perf/tests/csharp/csharp_compiler.csx

@@ -27,9 +27,9 @@ class CSharpCompilerTest: PerfTest
         ShellOutVital(ReleaseCscPath, args, executeInDirectory);
     }
     
-    public override int Iterations => 1;
+    public override int Iterations => 2;
     public override string Name => "csharp " + _rspFile;
-    public override string MeasuredProc => "csc.exe";
+    public override string MeasuredProc => "csc";
 }
 
 TestThisPlease(

src/Test/Perf/tests/helloworld/hello_world.csx

@@ -21,9 +21,9 @@ class HelloWorldTest: PerfTest
         ShellOutVital(ReleaseCscPath, _pathToHelloWorld + " /out:" + _pathToOutput);
     }
     
-    public override int Iterations => 1;
+    public override int Iterations => 2;
     public override string Name => "hello world";
-    public override string MeasuredProc => "csc.exe";
+    public override string MeasuredProc => "csc";
 }
 
 TestThisPlease(new HelloWorldTest());

src/Test/Perf/util/scenario_generator_util.csx

@@ -26,7 +26,6 @@ public class ScenarioGenerator
         }
 
         _buffer = new List<string>();
-        AddScenariosFileStart();
     }
 
     public void AddScenariosFileStart()

src/Test/Perf/util/tools_util.csx

@@ -31,6 +31,7 @@ bool ConvertConsumptionToCsv(string source, string destination, string requiredM
                     if (xmlReader.Name.Equals("ScenarioResult"))
                     {
                         currentScenarioName = xmlReader.GetAttribute("Name");
+                        currentScenarioName = new string(currentScenarioName.TakeWhile(c => !Char.IsDigit(c)).ToArray());
 
                         // These are not test results
                         if (string.Equals(currentScenarioName, "..TestDiagnostics.."))
@@ -132,16 +133,26 @@ void UploadTraces(string sourceFolderPath, string destinationFolderPath)
     Log("Uploading traces");
     if (Directory.Exists(sourceFolderPath))
     {
-        // Get the latest written databackup
-        var directoryToUpload = new DirectoryInfo(sourceFolderPath).GetDirectories("DataBackup*").OrderByDescending(d=>d.LastWriteTimeUtc).FirstOrDefault();
-        if (directoryToUpload == null)
+        var directoriesToUpload = new DirectoryInfo(sourceFolderPath).GetDirectories("DataBackup*");
+        if (directoriesToUpload.Count() == 0)
         {
             Log($"There are no trace directory starting with DataBackup in {sourceFolderPath}");
             return;
         }
 
-        var destination = Path.Combine(destinationFolderPath, directoryToUpload.Name);
-        CopyDirectory(directoryToUpload.FullName, destination);
+        var perfResultDestinationFolderName = string.Format("PerfResults-{0:yyyy-MM-dd_hh-mm-ss-tt}", DateTime.Now);
+        
+       var destination = Path.Combine(destinationFolderPath, perfResultDestinationFolderName);
+        foreach (var directoryToUpload in directoriesToUpload)
+        {
+            var destinationDataBackupDirectory = Path.Combine(destination, directoryToUpload.Name);
+            if (Directory.Exists(destinationDataBackupDirectory))
+            {
+                Directory.CreateDirectory(destinationDataBackupDirectory);
+            }
+            
+            CopyDirectory(directoryToUpload.FullName, destinationDataBackupDirectory);
+        }
 
         foreach(var file in new DirectoryInfo(sourceFolderPath).GetFiles().Where(f => f.Name.StartsWith("ConsumptionTemp", StringComparison.OrdinalIgnoreCase) || f.Name.StartsWith("Roslyn-", StringComparison.OrdinalIgnoreCase)))
         {

src/Test/Perf/util/trace_manager_util.csx

@@ -7,8 +7,9 @@ using System.IO;
 
 interface ITraceManager
 {
-    int Iterations { get; }
+    bool HasWarmUpIteration { get; }
 
+    void Initialize();
     void Cleanup();
     void EndEvent();
     void EndScenario();
@@ -18,24 +19,25 @@ interface ITraceManager
     void Start();
     void StartEvent();
     void StartScenario(string scenarioName, string processName);
+    void StartScenarios();
     void Stop();
     void WriteScenariosFileToDisk();
 }
 
 class TraceManagerFactory
 {
-    public static ITraceManager GetTraceManager(int iterations = 1)
+    public static ITraceManager GetTraceManager()
     {
         var directoryInfo = new RelativeDirectory();
         var cpcFullPath = Path.Combine(directoryInfo.CPCDirectoryPath, "CPC.exe");
         var scenarioPath = directoryInfo.CPCDirectoryPath;
         if (File.Exists(cpcFullPath))
         {
-            return new TraceManager(iterations, cpcFullPath, scenarioPath);
+            return new TraceManager(cpcFullPath, scenarioPath);
         }
         else
         {
-            return new NoOpTraceManager(iterations);
+            return new NoOpTraceManager();
         }
     }
 }
@@ -44,18 +46,20 @@ class TraceManagerFactory
 /// All operations are NoOp
 class NoOpTraceManager : ITraceManager
 {
-    private readonly int _iterations;
-    public NoOpTraceManager(int iterations)
+    public NoOpTraceManager()
     {
-        _iterations = iterations;
     }
 
-    public int Iterations
+    public bool HasWarmUpIteration
     {
         get
         {
-            return _iterations;
-        }
+            return false;  
+        }    
+    }
+    
+    public void Initialize()
+    {
     }
 
     public void Cleanup()
@@ -90,6 +94,10 @@ class NoOpTraceManager : ITraceManager
     {
     }
 
+    public void StartScenarios()
+    {
+    }
+
     public void StartScenario(string scenarioName, string processName)
     {
     }
@@ -106,7 +114,6 @@ class NoOpTraceManager : ITraceManager
 class TraceManager: ITraceManager
 {
     private readonly ScenarioGenerator _scenarioGenerator;
-    private readonly int _iterations;
     private readonly string _cpcPath;
     
     private RelativeDirectory _directoryInfo = new RelativeDirectory();
@@ -115,20 +122,37 @@ class TraceManager: ITraceManager
     private int _stopEventAbsoluteInstance = 1;
 
     public TraceManager(
-        int iterations,
         string cpcPath,
         string scenarioPath): base()
     {
-        _iterations = iterations;
         _cpcPath = cpcPath;
         _scenarioGenerator = new ScenarioGenerator(scenarioPath);
     }
 
-    public int Iterations
+    public bool HasWarmUpIteration
     {
         get
         {
-            return _iterations;
+            return true;
+        }    
+    }
+    
+    // Cleanup the results directory and files before every run
+    public void Initialize()
+    {
+        var consumptionTempResultsPath = Path.Combine(_directoryInfo.CPCDirectoryPath, "ConsumptionTempResults.xml");
+        if (File.Exists(consumptionTempResultsPath))
+        {
+            File.Delete(consumptionTempResultsPath);
+        }
+        
+        if (Directory.Exists(_directoryInfo.CPCDirectoryPath))
+        {
+            var databackDirectories = Directory.GetDirectories(_directoryInfo.CPCDirectoryPath, "DataBackup*", SearchOption.AllDirectories);
+            foreach (var databackDirectory in databackDirectories)
+            {
+                Directory.Delete(databackDirectory, true);
+            }
         }
     }
 
@@ -145,7 +169,7 @@ class TraceManager: ITraceManager
     public void Stop()
     {
         var scenariosXmlPath = Path.Combine(_directoryInfo.CPCDirectoryPath, "scenarios.xml");
-        var consumptionTempResultsPath = Path.Combine(_directoryInfo.CPCDirectoryPath, "ConsumptionTempResultsPath.xml");
+        var consumptionTempResultsPath = Path.Combine(_directoryInfo.CPCDirectoryPath, "ConsumptionTempResults.xml");
         ShellOutVital(_cpcPath, $"/Stop /DisableArchive /ScenarioPath=\"{scenariosXmlPath}\" /ConsumptionTempResultsPath=\"{consumptionTempResultsPath}\"");
     }
 
@@ -153,6 +177,11 @@ class TraceManager: ITraceManager
     {
         ShellOutVital(_cpcPath, "/Cleanup /DisableArchive");
     }
+    
+    public void StartScenarios()
+    {
+        _scenarioGenerator.AddScenariosFileStart();
+    }
 
     public void StartScenario(string scenarioName, string processName)
     {

src/Test/Utilities/Desktop/CommonTestBase.CompilationVerifier.cs

@@ -45,11 +45,6 @@ public class CompilationVerifier
                 _dependencies = dependencies;
             }
 
-            public CompilationVerifier Clone()
-            {
-                return new CompilationVerifier(_test, _compilation, _dependencies);
-            }
-
             internal CompilationTestData TestData
             {
                 get { return _testData; }
@@ -94,7 +89,7 @@ internal ImmutableArray<ModuleMetadata> GetAllModuleMetadata()
 
             public void Emit(string expectedOutput, IEnumerable<ResourceDescription> manifestResources, bool peVerify, SignatureDescription[] expectedSignatures)
             {
-                using (var testEnvironment = new HostedRuntimeEnvironment(_dependencies))
+                using (var testEnvironment = RuntimeEnvironmentFactory.Create(_dependencies))
                 {
                     string mainModuleName = Emit(testEnvironment, manifestResources);
                     _allModuleData = testEnvironment.GetAllModuleData();
@@ -120,7 +115,7 @@ public void Emit(string expectedOutput, IEnumerable<ResourceDescription> manifes
             // Replace bool verify parameter with string[] expectedPeVerifyOutput. If null, no verification. If empty verify have to succeed. Otherwise compare errors.
             public void EmitAndVerify(params string[] expectedPeVerifyOutput)
             {
-                using (var testEnvironment = new HostedRuntimeEnvironment(_dependencies))
+                using (var testEnvironment = RuntimeEnvironmentFactory.Create(_dependencies))
                 {
                     string mainModuleName = Emit(testEnvironment, null);
                     string[] actualOutput = testEnvironment.PeVerifyModules(new[] { mainModuleName }, throwOnError: false);
@@ -128,14 +123,14 @@ public void EmitAndVerify(params string[] expectedPeVerifyOutput)
                 }
             }
 
-            private string Emit(HostedRuntimeEnvironment testEnvironment, IEnumerable<ResourceDescription> manifestResources)
+            private string Emit(IRuntimeEnvironment testEnvironment, IEnumerable<ResourceDescription> manifestResources)
             {
                 testEnvironment.Emit(_compilation, manifestResources);
 
                 _diagnostics = testEnvironment.GetDiagnostics();
                 EmittedAssemblyData = testEnvironment.GetMainImage();
                 EmittedAssemblyPdb = testEnvironment.GetMainPdb();
-                _testData = testEnvironment.GetCompilationTestData();
+                _testData = ((IInternalRuntimeEnvironment) testEnvironment).GetCompilationTestData();
 
                 return _compilation.Assembly.Identity.GetDisplayName();
             }

src/Test/Utilities/Desktop/Exceptions.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.Concurrent;
 using System.Collections.Generic;
-using System.Collections.Immutable;
-using System.Diagnostics;
-using System.IO;
-using System.Linq;
-using System.Reflection;
 using System.Runtime.Serialization;
-using System.Text;
-using System.Threading;
-using Microsoft.CodeAnalysis;
-using Microsoft.CodeAnalysis.CodeGen;
-using Microsoft.CodeAnalysis.Emit;
-using Roslyn.Utilities;
+using static Roslyn.Test.Utilities.ExceptionHelper; 
 
 namespace Microsoft.CodeAnalysis.Test.Utilities
 {
@@ -23,84 +12,35 @@ public class EmitException : Exception
     {
         public IEnumerable<Diagnostic> Diagnostics { get; }
 
-        protected EmitException(SerializationInfo info, StreamingContext context) : base(info, context) { }
+        protected EmitException(SerializationInfo info, StreamingContext context) 
+            : base(info, context) { }
 
         public EmitException(IEnumerable<Diagnostic> diagnostics, string directory)
             : base(GetMessageFromResult(diagnostics, directory))
         {
             this.Diagnostics = diagnostics;
         }
-
-        private static string GetMessageFromResult(IEnumerable<Diagnostic> diagnostics, string directory)
-        {
-            StringBuilder sb = new StringBuilder();
-            sb.AppendLine("Emit Failed, binaries saved to: ");
-            sb.AppendLine(directory);
-            foreach (var d in diagnostics)
-            {
-                sb.AppendLine(d.ToString());
-            }
-            return sb.ToString();
-        }
     }
 
     [Serializable]
     public class PeVerifyException : Exception
     {
-        protected PeVerifyException(SerializationInfo info, StreamingContext context) : base(info, context) { }
+        protected PeVerifyException(SerializationInfo info, StreamingContext context) 
+            : base(info, context) { }
 
-        public PeVerifyException(string output, string exePath) : base(GetMessageFromResult(output, exePath)) { }
+        public PeVerifyException(string output, string exePath) 
+            : base(GetMessageFromResult(output, exePath)) { }
 
-        private static string GetMessageFromResult(string output, string exePath)
-        {
-            StringBuilder sb = new StringBuilder();
-            sb.AppendLine();
-            sb.Append("PeVerify failed for assembly '");
-            sb.Append(exePath);
-            sb.AppendLine("':");
-            sb.AppendLine(output);
-            return sb.ToString();
-        }
     }
 
     [Serializable]
     public class ExecutionException : Exception
     {
-        public ExecutionException(string expectedOutput, string actualOutput, string exePath) : base(GetMessageFromResult(expectedOutput, actualOutput, exePath)) { }
+        public ExecutionException(string expectedOutput, string actualOutput, string exePath) 
+            : base(GetMessageFromResult(expectedOutput, actualOutput, exePath)) { }
 
-        public ExecutionException(Exception innerException, string exePath) : base(GetMessageFromException(innerException, exePath), innerException) { }
+        public ExecutionException(Exception innerException, string exePath) 
+            : base(GetMessageFromException(innerException, exePath), innerException) { }
 
-        private static string GetMessageFromException(Exception executionException, string exePath)
-        {
-            StringBuilder sb = new StringBuilder();
-            sb.AppendLine();
-            sb.Append("Execution failed for assembly '");
-            sb.Append(exePath);
-            sb.AppendLine("'.");
-            sb.Append("Exception: " + executionException);
-            return sb.ToString();
-        }
-
-        private static string GetMessageFromResult(string expectedOutput, string actualOutput, string exePath)
-        {
-            StringBuilder sb = new StringBuilder();
-            sb.AppendLine();
-            sb.Append("Execution failed for assembly '");
-            sb.Append(exePath);
-            sb.AppendLine("'.");
-            if (expectedOutput != null)
-            {
-                sb.Append("Expected: ");
-                sb.AppendLine(expectedOutput);
-                sb.Append("Actual:   ");
-                sb.AppendLine(actualOutput);
-            }
-            else
-            {
-                sb.Append("Output: ");
-                sb.AppendLine(actualOutput);
-            }
-            return sb.ToString();
-        }
     }
 }

src/Test/Utilities/Desktop/HostedRuntimeEnvironment.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.Concurrent;
 using System.Collections.Generic;
 using System.Collections.Immutable;
-using System.Diagnostics;
 using System.IO;
 using System.Linq;
 using System.Reflection;
-using System.Runtime.Serialization;
-using System.Text;
 using System.Threading;
 using Microsoft.CodeAnalysis;
 using Microsoft.CodeAnalysis.CodeGen;
 using Microsoft.CodeAnalysis.Emit;
+using Roslyn.Test.Utilities;
 using Roslyn.Utilities;
+using static Roslyn.Test.Utilities.RuntimeUtilities; 
 
 namespace Microsoft.CodeAnalysis.Test.Utilities
 {
-    public sealed class HostedRuntimeEnvironment : IDisposable
+    public sealed class HostedRuntimeEnvironment : IDisposable, IRuntimeEnvironment, IInternalRuntimeEnvironment
     {
         private sealed class RuntimeData : IDisposable
         {
@@ -55,18 +53,6 @@ public void Dispose()
             }
         }
 
-        private struct EmitOutput
-        {
-            internal ImmutableArray<byte> Assembly { get; }
-            internal ImmutableArray<byte> Pdb { get; }
-
-            internal EmitOutput(ImmutableArray<byte> assembly, ImmutableArray<byte> pdb)
-            {
-                Assembly = assembly;
-                Pdb = pdb;
-            }
-        }
-
         private sealed class EmitData
         {
             internal RuntimeData RuntimeData;
@@ -200,200 +186,6 @@ private static RuntimeData CreateRuntimeData()
             }
         }
 
-        /// <summary>
-        /// Find all of the <see cref="Compilation"/> values reachable from this instance.
-        /// </summary>
-        /// <param name="compilation"></param>
-        /// <returns></returns>
-        private static List<Compilation> FindReferencedCompilations(Compilation original)
-        {
-            var list = new List<Compilation>();
-            var toVisit = new Queue<Compilation>(FindDirectReferencedCompilations(original));
-
-            while (toVisit.Count > 0)
-            {
-                var current = toVisit.Dequeue();
-                if (list.Contains(current))
-                {
-                    continue;
-                }
-
-                list.Add(current);
-
-                foreach (var other in FindDirectReferencedCompilations(current))
-                {
-                    toVisit.Enqueue(other);
-                }
-            }
-
-            return list;
-        }
-
-        private static List<Compilation> FindDirectReferencedCompilations(Compilation compilation)
-        {
-            var list = new List<Compilation>();
-            var previousCompilation = compilation.ScriptCompilationInfo?.PreviousScriptCompilation;
-            if (previousCompilation != null)
-            {
-                list.Add(previousCompilation);
-            }
-
-            foreach (var reference in compilation.References.OfType<CompilationReference>())
-            {
-                list.Add(reference.Compilation);
-            }
-
-            return list;
-        }
-
-        /// <summary>
-        /// Emit all of the references which are not directly or indirectly a <see cref="Compilation"/> value.
-        /// </summary>
-        private static void EmitReferences(Compilation compilation, HashSet<string> fullNameSet, List<ModuleData> dependencies, DiagnosticBag diagnostics)
-        {
-            // NOTE: specifically don't need to consider previous submissions since they will always be compilations.
-            foreach (var metadataReference in compilation.References)
-            {
-                if (metadataReference is CompilationReference)
-                {
-                    continue;
-                }
-
-                var peRef = (PortableExecutableReference)metadataReference;
-                var metadata = peRef.GetMetadata();
-                var isManifestModule = peRef.Properties.Kind == MetadataImageKind.Assembly;
-                var identity = isManifestModule
-                    ? ((AssemblyMetadata)metadata).GetAssembly().Identity
-                    : null;
-
-                // If this is an indirect reference to a Compilation then it is already been emitted 
-                // so no more work to be done.
-                if (isManifestModule && fullNameSet.Contains(identity.GetDisplayName()))
-                {
-                    continue;
-                }
-
-                foreach (var module in EnumerateModules(metadata))
-                {
-                    ImmutableArray<byte> bytes = module.Module.PEReaderOpt.GetEntireImage().GetContent();
-                    ModuleData moduleData;
-                    if (isManifestModule)
-                    {
-                        fullNameSet.Add(identity.GetDisplayName());
-                        moduleData = new ModuleData(identity,
-                                                    OutputKind.DynamicallyLinkedLibrary,
-                                                    bytes,
-                                                    pdb: default(ImmutableArray<byte>),
-                                                    inMemoryModule: true);
-                    }
-                    else
-                    {
-                        moduleData = new ModuleData(module.Name,
-                                                    bytes,
-                                                    pdb: default(ImmutableArray<byte>),
-                                                    inMemoryModule: true);
-                    }
-
-                    dependencies.Add(moduleData);
-                    isManifestModule = false;
-                }
-            }
-        }
-
-        private static IEnumerable<ModuleMetadata> EnumerateModules(Metadata metadata)
-        {
-            return (metadata.Kind == MetadataImageKind.Assembly) ? ((AssemblyMetadata)metadata).GetModules().AsEnumerable() : SpecializedCollections.SingletonEnumerable((ModuleMetadata)metadata);
-        }
-
-        private static EmitOutput? EmitCompilation(
-            Compilation compilation,
-            IEnumerable<ResourceDescription> manifestResources,
-            List<ModuleData> dependencies,
-            DiagnosticBag diagnostics,
-            CompilationTestData testData
-        )
-        {
-            // A Compilation can appear multiple times in a depnedency graph as both a Compilation and as a MetadataReference
-            // value.  Iterate the Compilations eagerly so they are always emitted directly and later references can re-use 
-            // the value.  This gives better, and consistent, diagostic information.
-            var referencedCompilations = FindReferencedCompilations(compilation);
-            var fullNameSet = new HashSet<string>(StringComparer.OrdinalIgnoreCase);
-
-            foreach (var referencedCompilation in referencedCompilations)
-            {
-                var emitData = EmitCompilationCore(referencedCompilation, null, diagnostics, null);
-                if (emitData.HasValue)
-                {
-                    var moduleData = new ModuleData(referencedCompilation.Assembly.Identity,
-                                                    OutputKind.DynamicallyLinkedLibrary,
-                                                    emitData.Value.Assembly,
-                                                    pdb: default(ImmutableArray<byte>),
-                                                    inMemoryModule: true);
-                    fullNameSet.Add(moduleData.Id.FullName);
-                    dependencies.Add(moduleData);
-                }
-            }
-
-            // Now that the Compilation values have been emitted, emit the non-compilation references
-            foreach (var current in (new[] { compilation }).Concat(referencedCompilations))
-            {
-                EmitReferences(current, fullNameSet, dependencies, diagnostics);
-            }
-
-            return EmitCompilationCore(compilation, manifestResources, diagnostics, testData);
-        }
-
-        private static EmitOutput? EmitCompilationCore(
-            Compilation compilation,
-            IEnumerable<ResourceDescription> manifestResources,
-            DiagnosticBag diagnostics,
-            CompilationTestData testData
-        )
-        {
-            using (var executableStream = new MemoryStream())
-            {
-                var pdb = default(ImmutableArray<byte>);
-                var assembly = default(ImmutableArray<byte>);
-                var pdbStream = MonoHelpers.IsRunningOnMono()
-                    ? null
-                    : new MemoryStream();
-
-                EmitResult result;
-                try
-                {
-                    result = compilation.Emit(
-                        executableStream,
-                        pdbStream: pdbStream,
-                        xmlDocumentationStream: null,
-                        win32Resources: null,
-                        manifestResources: manifestResources,
-                        options: EmitOptions.Default,
-                        debugEntryPoint: null,
-                        testData: testData,
-                        getHostDiagnostics: null,
-                        cancellationToken: default(CancellationToken));
-                }
-                finally
-                {
-                    if (pdbStream != null)
-                    {
-                        pdb = pdbStream.ToImmutable();
-                        pdbStream.Dispose();
-                    }
-                }
-
-                diagnostics.AddRange(result.Diagnostics);
-                assembly = executableStream.ToImmutable();
-
-                if (result.Success)
-                {
-                    return new EmitOutput(assembly, pdb);
-                }
-
-                return null;
-            }
-        }
-
         public void Emit(
             Compilation mainCompilation,
             IEnumerable<ResourceDescription> manifestResources,
@@ -430,7 +222,7 @@ CompilationTestData testData
             else
             {
                 string dumpDir;
-                RuntimeAssemblyManager.DumpAssemblyData(dependencies, out dumpDir);
+                DumpAssemblyData(dependencies, out dumpDir);
 
                 // This method MUST throw if compilation did not succeed.  If compilation succeeded and there were errors, that is bad.
                 // Please see KevinH if you intend to change this behavior as many tests expect the Exception to indicate failure.
@@ -484,7 +276,7 @@ private EmitData GetEmitData()
             return _emitData;
         }
 
-        internal ImmutableArray<Diagnostic> GetDiagnostics()
+        public ImmutableArray<Diagnostic> GetDiagnostics()
         {
             return GetEmitData().Diagnostics;
         }
@@ -499,7 +291,7 @@ public ImmutableArray<byte> GetMainPdb()
             return GetEmitData().MainModulePdb;
         }
 
-        internal IList<ModuleData> GetAllModuleData()
+        public IList<ModuleData> GetAllModuleData()
         {
             return GetEmitData().AllModuleData;
         }
@@ -511,14 +303,14 @@ public void PeVerify()
             emitData.Manager.PeVerifyModules(new[] { emitData.MainModule.FullName });
         }
 
-        internal string[] PeVerifyModules(string[] modulesToVerify, bool throwOnError = true)
+        public string[] PeVerifyModules(string[] modulesToVerify, bool throwOnError = true)
         {
             var emitData = GetEmitData();
             emitData.RuntimeData.PeverifyRequested = true;
             return emitData.Manager.PeVerifyModules(modulesToVerify, throwOnError);
         }
 
-        internal SortedSet<string> GetMemberSignaturesFromMetadata(string fullyQualifiedTypeName, string memberName)
+        public SortedSet<string> GetMemberSignaturesFromMetadata(string fullyQualifiedTypeName, string memberName)
         {
             var emitData = GetEmitData();
             var searchIds = emitData.AllModuleData.Select(x => x.Id).ToList();
@@ -554,7 +346,7 @@ void IDisposable.Dispose()
             _disposed = true;
         }
 
-        internal CompilationTestData GetCompilationTestData()
+        CompilationTestData IInternalRuntimeEnvironment.GetCompilationTestData()
         {
             if (_testData.Module == null)
             {

src/Test/Utilities/Desktop/MetadataSignatureUnitTestHelper.cs

@@ -15,15 +15,15 @@ public class SignatureDescription
         public string ExpectedSignature { get; set; }
     }
 
-    public class MetadataSignatureUnitTestHelper
+    internal class MetadataSignatureUnitTestHelper
     {
         /// <summary>
         /// Uses Reflection to verify that the specified member signatures are present in emitted metadata
         /// </summary>
         /// <param name="appDomainHost">Unit test AppDomain host</param>
         /// <param name="expectedSignatures">Baseline signatures - use the Signature() factory method to create instances of SignatureDescription</param>
-        public static void VerifyMemberSignatures(
-            HostedRuntimeEnvironment appDomainHost, params SignatureDescription[] expectedSignatures)
+        internal static void VerifyMemberSignatures(
+            IRuntimeEnvironment appDomainHost, params SignatureDescription[] expectedSignatures)
         {
             Assert.NotNull(expectedSignatures);
             Assert.NotEmpty(expectedSignatures);
@@ -76,7 +76,7 @@ public class MetadataSignatureUnitTestHelper
         /// <param name="actualSignatures">List of found signatures matching member name</param>
         /// <returns>True if a matching member signature was found, false otherwise</returns>
         private static bool VerifyMemberSignatureHelper(
-            HostedRuntimeEnvironment appDomainHost, string fullyQualifiedTypeName, string memberName,
+            IRuntimeEnvironment appDomainHost, string fullyQualifiedTypeName, string memberName,
             ref string expectedSignature, out List<string> actualSignatures)
         {
             Assert.False(string.IsNullOrWhiteSpace(fullyQualifiedTypeName), "'fullyQualifiedTypeName' can't be null or empty");

src/Test/Utilities/Desktop/RuntimeAssemblyManager.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.Concurrent;
 using System.Collections.Generic;
 using System.Collections.Immutable;
 using System.Diagnostics;
-using System.IO;
 using System.Linq;
 using System.Reflection;
-using System.Runtime.Serialization;
 using System.Text;
-using System.Threading;
-using Microsoft.CodeAnalysis;
-using Microsoft.CodeAnalysis.CodeGen;
-using Microsoft.CodeAnalysis.Emit;
-using Roslyn.Utilities;
+using Roslyn.Test.Utilities;
 
 namespace Microsoft.CodeAnalysis.Test.Utilities
 {
@@ -46,8 +39,6 @@ internal AssemblyData(Assembly assembly)
             }
         }
 
-        private static int s_dumpCount;
-
         private readonly AppDomainAssemblyCache _assemblyCache = AppDomainAssemblyCache.GetOrCreate();
         private readonly Dictionary<string, AssemblyData> _fullNameToAssemblyDataMap;
         private readonly Dictionary<Guid, AssemblyData> _mvidToAssemblyDataMap;
@@ -90,6 +81,11 @@ public RuntimeAssemblyManager()
             }
         }
 
+        public string DumpAssemblyData(out string dumpDirectory)
+        {
+            return RuntimeUtilities.DumpAssemblyData(ModuleDatas, out dumpDirectory);
+        }
+
         public void Dispose()
         {
             // clean up our handlers, so that they don't accumulate
@@ -430,87 +426,6 @@ public int Execute(string moduleName, int expectedOutputLength, out string outpu
             return result is int ? (int)result : 0;
         }
 
-        public string DumpAssemblyData(out string dumpDirectory)
-        {
-            return DumpAssemblyData(ModuleDatas, out dumpDirectory);
-        }
-
-        public static string DumpAssemblyData(IEnumerable<ModuleData> modules, out string dumpDirectory)
-        {
-            dumpDirectory = null;
-
-            StringBuilder sb = new StringBuilder();
-            foreach (var module in modules)
-            {
-                // Limit the number of dumps to 10.  After 10 we're likely in a bad state and are 
-                // dumping lots of unnecessary data.
-                if (s_dumpCount > 10)
-                {
-                    break;
-                }
-
-                if (module.InMemoryModule)
-                {
-                    Interlocked.Increment(ref s_dumpCount);
-
-                    if (dumpDirectory == null)
-                    {
-                        var assemblyLocation = typeof(HostedRuntimeEnvironment).Assembly.Location;
-                        dumpDirectory = Path.Combine(
-                            Path.GetDirectoryName(assemblyLocation),
-                            "Dumps");
-                        try
-                        {
-                            Directory.CreateDirectory(dumpDirectory);
-                        }
-                        catch
-                        {
-                            // Okay if directory already exists
-                        }
-                    }
-
-                    string fileName;
-                    if (module.Kind == OutputKind.NetModule)
-                    {
-                        fileName = module.FullName;
-                    }
-                    else
-                    {
-                        AssemblyIdentity identity;
-                        AssemblyIdentity.TryParseDisplayName(module.FullName, out identity);
-                        fileName = identity.Name;
-                    }
-
-                    string pePath = Path.Combine(dumpDirectory, fileName + module.Kind.GetDefaultExtension());
-                    string pdbPath = (module.Pdb != null) ? pdbPath = Path.Combine(dumpDirectory, fileName + ".pdb") : null;
-                    try
-                    {
-                        module.Image.WriteToFile(pePath);
-                        if (pdbPath != null)
-                        {
-                            module.Pdb.WriteToFile(pdbPath);
-                        }
-                    }
-                    catch (IOException)
-                    {
-                        pePath = "<unable to write file>";
-                        if (pdbPath != null)
-                        {
-                            pdbPath = "<unable to write file>";
-                        }
-                    }
-                    sb.Append("PE(" + module.Kind + "): ");
-                    sb.AppendLine(pePath);
-                    if (pdbPath != null)
-                    {
-                        sb.Append("PDB: ");
-                        sb.AppendLine(pdbPath);
-                    }
-                }
-            }
-            return sb.ToString();
-        }
-
         public string[] PeVerifyModules(string[] modulesToVerify, bool throwOnError = true)
         {
             // For Windows RT (ARM) THE CLRHelper.Peverify appears to not work and will exclude this 
@@ -552,7 +467,7 @@ public string[] PeVerifyModules(string[] modulesToVerify, bool throwOnError = tr
             if (throwOnError && errors.Length > 0)
             {
                 string dumpDir;
-                DumpAssemblyData(ModuleDatas, out dumpDir);
+                RuntimeUtilities.DumpAssemblyData(ModuleDatas, out dumpDir);
                 throw new PeVerifyException(errors.ToString(), dumpDir);
             }
             return allOutput.ToArray();

src/Test/Utilities/Portable/CoreCLRRuntimeEnvironment.cs

+// Copyright (c) Microsoft.  All Rights Reserved.  Licensed under the Apache License, Version 2.0.  See License.txt in the project root for license information.
+using System;
+using System.Collections.Generic;
+using System.Collections.Immutable;
+using Microsoft.CodeAnalysis.CodeGen;
+using Roslyn.Test.Utilities;
+using static Roslyn.Test.Utilities.RuntimeUtilities; 
+
+namespace Microsoft.CodeAnalysis.Test.Utilities
+{
+    public class CoreCLRRuntimeEnvironment : IRuntimeEnvironment, IInternalRuntimeEnvironment
+    {
+        private IEnumerable<ModuleData> _additionalDependencies;
+        private CompilationTestData _testData = new CompilationTestData();
+        private ImmutableArray<byte> _mainImage;
+        private ImmutableArray<byte> _pdb;
+        private ImmutableArray<Diagnostic> _diagnostics;
+
+        public CoreCLRRuntimeEnvironment(IEnumerable<ModuleData> additionalDependencies = null)
+        {
+            _additionalDependencies = additionalDependencies;
+        }
+
+        public void Emit(Compilation mainCompilation, IEnumerable<ResourceDescription> manifestResources, bool usePdbForDebugging = false)
+        {
+            _testData.Methods.Clear();
+            var diagnostics = DiagnosticBag.GetInstance();
+            var dependencies = new List<ModuleData>();
+            var mainOutput = RuntimeUtilities.EmitCompilation(mainCompilation, manifestResources, dependencies, diagnostics, _testData);
+
+            if (mainOutput.HasValue)
+            {
+                _diagnostics = diagnostics.ToReadOnly();
+                _mainImage = mainOutput.Value.Assembly;
+                _pdb = mainOutput.Value.Pdb;
+            }
+            else
+            {
+                _mainImage = default(ImmutableArray<byte>);
+                _pdb = default(ImmutableArray<byte>);
+                _diagnostics = default(ImmutableArray<Diagnostic>);
+
+                string dumpDir;
+                DumpAssemblyData(dependencies, out dumpDir);
+                throw new EmitException(diagnostics.ToReadOnly(), dumpDir);
+            }
+        }
+
+        public int Execute(string moduleName, string expectedOutput)
+        {
+            throw new NotImplementedException();
+        }
+
+        public IList<ModuleData> GetAllModuleData()
+        {
+            throw new NotImplementedException();
+        }
+
+        public ImmutableArray<Diagnostic> GetDiagnostics() => _diagnostics;
+        public ImmutableArray<byte> GetMainImage() => _mainImage;
+        public ImmutableArray<byte> GetMainPdb() => _pdb;
+
+        public SortedSet<string> GetMemberSignaturesFromMetadata(string fullyQualifiedTypeName, string memberName)
+        {
+            throw new NotImplementedException();
+        }
+
+        public void PeVerify()
+        {
+            throw new NotImplementedException();
+        }
+
+        public string[] PeVerifyModules(string[] modulesToVerify, bool throwOnError = true)
+        {
+            throw new NotImplementedException();
+        }
+
+        CompilationTestData IInternalRuntimeEnvironment.GetCompilationTestData()
+        {
+            return _testData;
+        }
+
+        public void Dispose()
+        {
+            // We need Dispose to satisfy the IRuntimeEnvironment interface, but 
+            // we don't really need it.
+        }
+    }
+}

src/Test/Utilities/Portable/Exceptions.cs

+// Copyright (c) Microsoft.  All Rights Reserved.  Licensed under the Apache License, Version 2.0.  See License.txt in the project root for license information.
+
+using System;
+using System.Collections.Generic;
+using static Roslyn.Test.Utilities.ExceptionHelper; 
+
+namespace Microsoft.CodeAnalysis.Test.Utilities
+{
+    public sealed class EmitException : Exception
+    {
+        public IEnumerable<Diagnostic> Diagnostics { get; }
+
+        internal EmitException(IEnumerable<Diagnostic> diagnostics, string directory)
+            : base(GetMessageFromResult(diagnostics, directory))
+        {
+            this.Diagnostics = diagnostics;
+        }
+    }
+
+    public sealed class PeVerifyException : Exception
+    {
+        internal PeVerifyException(string output, string exePath) : base(GetMessageFromResult(output, exePath)) { }
+    }
+
+    public sealed class ExecutionException : Exception
+    {
+        internal ExecutionException(string expectedOutput, string actualOutput, string exePath) : base(GetMessageFromResult(expectedOutput, actualOutput, exePath)) { }
+
+        internal ExecutionException(Exception innerException, string exePath) : base(GetMessageFromException(innerException, exePath), innerException) { }
+    }
+}

src/Test/Utilities/Portable/TestUtilities.csproj

@@ -115,6 +115,8 @@
   </ItemGroup>
   <ItemGroup>
     <Compile Include="CommonTestBase.cs" />
+    <Compile Include="CoreCLRRuntimeEnvironment.cs" />
+    <Compile Include="Exceptions.cs" />
     <Compile Include="ICompilationVerifier.cs" />
     <Compile Include="MetadataSignatureUnitTestHelper.cs" />
     <Compile Include="ModuleData.cs" />

src/Test/Utilities/Shared/Compilation/IRuntimeEnvironment.cs

+// Copyright (c) Microsoft.  All Rights Reserved.  Licensed under the Apache License, Version 2.0.  See License.txt in the project root for license information.
+using System;
+using System.Collections.Generic;
+using System.Collections.Immutable;
+using System.IO;
+using System.Linq;
+using System.Text;
+using System.Threading;
+using Microsoft.CodeAnalysis;
+using Microsoft.CodeAnalysis.CodeGen;
+using Microsoft.CodeAnalysis.Emit;
+using Microsoft.CodeAnalysis.Test.Utilities;
+using Roslyn.Utilities;
+
+namespace Roslyn.Test.Utilities
+{
+
+    public class RuntimeEnvironmentFactory
+    {
+        internal static IRuntimeEnvironment Create(IEnumerable<ModuleData> additionalDependencies = null)
+    {
+
+#if DNX
+            return new CoreCLRRuntimeEnvironment(additionalDependencies);
+#else
+            return new HostedRuntimeEnvironment(additionalDependencies);
+#endif
+        }
+    }
+
+    internal struct EmitOutput
+    {
+        internal ImmutableArray<byte> Assembly { get; }
+        internal ImmutableArray<byte> Pdb { get; }
+
+        internal EmitOutput(ImmutableArray<byte> assembly, ImmutableArray<byte> pdb)
+        {
+            Assembly = assembly;
+            Pdb = pdb;
+        }
+    }
+
+    internal static class RuntimeUtilities
+    {
+
+        private static int s_dumpCount;
+
+        private static IEnumerable<ModuleMetadata> EnumerateModules(Metadata metadata)
+        {
+            return (metadata.Kind == MetadataImageKind.Assembly) ? ((AssemblyMetadata)metadata).GetModules().AsEnumerable() : SpecializedCollections.SingletonEnumerable((ModuleMetadata)metadata);
+        }
+
+        /// <summary>
+        /// Emit all of the references which are not directly or indirectly a <see cref="Compilation"/> value.
+        /// </summary>
+        internal static void EmitReferences(Compilation compilation, HashSet<string> fullNameSet, List<ModuleData> dependencies, DiagnosticBag diagnostics)
+        {
+            // NOTE: specifically don't need to consider previous submissions since they will always be compilations.
+            foreach (var metadataReference in compilation.References)
+            {
+                if (metadataReference is CompilationReference)
+                {
+                    continue;
+                }
+
+                var peRef = (PortableExecutableReference)metadataReference;
+                var metadata = peRef.GetMetadata();
+                var isManifestModule = peRef.Properties.Kind == MetadataImageKind.Assembly;
+                var identity = isManifestModule
+                    ? ((AssemblyMetadata)metadata).GetAssembly().Identity
+                    : null;
+
+                // If this is an indirect reference to a Compilation then it is already been emitted 
+                // so no more work to be done.
+                if (isManifestModule && fullNameSet.Contains(identity.GetDisplayName()))
+                {
+                    continue;
+                }
+
+                foreach (var module in EnumerateModules(metadata))
+                {
+                    ImmutableArray<byte> bytes = module.Module.PEReaderOpt.GetEntireImage().GetContent();
+                    ModuleData moduleData;
+                    if (isManifestModule)
+                    {
+                        fullNameSet.Add(identity.GetDisplayName());
+                        moduleData = new ModuleData(identity,
+                                                    OutputKind.DynamicallyLinkedLibrary,
+                                                    bytes,
+                                                    pdb: default(ImmutableArray<byte>),
+                                                    inMemoryModule: true);
+                    }
+                    else
+                    {
+                        moduleData = new ModuleData(module.Name,
+                                                    bytes,
+                                                    pdb: default(ImmutableArray<byte>),
+                                                    inMemoryModule: true);
+                    }
+
+                    dependencies.Add(moduleData);
+                    isManifestModule = false;
+                }
+            }
+        }
+
+        /// <summary>
+        /// Find all of the <see cref="Compilation"/> values reachable from this instance.
+        /// </summary>
+        /// <param name="compilation"></param>
+        /// <returns></returns>
+        private static List<Compilation> FindReferencedCompilations(Compilation original)
+        {
+            var list = new List<Compilation>();
+            var toVisit = new Queue<Compilation>(FindDirectReferencedCompilations(original));
+
+            while (toVisit.Count > 0)
+            {
+                var current = toVisit.Dequeue();
+                if (list.Contains(current))
+                {
+                    continue;
+                }
+
+                list.Add(current);
+
+                foreach (var other in FindDirectReferencedCompilations(current))
+                {
+                    toVisit.Enqueue(other);
+                }
+            }
+
+            return list;
+        }
+
+        private static List<Compilation> FindDirectReferencedCompilations(Compilation compilation)
+        {
+            var list = new List<Compilation>();
+            var previousCompilation = compilation.ScriptCompilationInfo?.PreviousScriptCompilation;
+            if (previousCompilation != null)
+            {
+                list.Add(previousCompilation);
+            }
+
+            foreach (var reference in compilation.References.OfType<CompilationReference>())
+            {
+                list.Add(reference.Compilation);
+            }
+
+            return list;
+        }
+
+        internal static EmitOutput? EmitCompilation(
+            Compilation compilation,
+            IEnumerable<ResourceDescription> manifestResources,
+            List<ModuleData> dependencies,
+            DiagnosticBag diagnostics,
+            CompilationTestData testData
+        )
+        {
+            // A Compilation can appear multiple times in a depnedency graph as both a Compilation and as a MetadataReference
+            // value.  Iterate the Compilations eagerly so they are always emitted directly and later references can re-use 
+            // the value.  This gives better, and consistent, diagostic information.
+            var referencedCompilations = FindReferencedCompilations(compilation);
+            var fullNameSet = new HashSet<string>(StringComparer.OrdinalIgnoreCase);
+
+            foreach (var referencedCompilation in referencedCompilations)
+            {
+                var emitData = RuntimeUtilities.EmitCompilationCore(referencedCompilation, null, diagnostics, null);
+                if (emitData.HasValue)
+                {
+                    var moduleData = new ModuleData(referencedCompilation.Assembly.Identity,
+                                                    OutputKind.DynamicallyLinkedLibrary,
+                                                    emitData.Value.Assembly,
+                                                    pdb: default(ImmutableArray<byte>),
+                                                    inMemoryModule: true);
+                    fullNameSet.Add(moduleData.Id.FullName);
+                    dependencies.Add(moduleData);
+                }
+            }
+
+            // Now that the Compilation values have been emitted, emit the non-compilation references
+            foreach (var current in (new[] { compilation }).Concat(referencedCompilations))
+            {
+                EmitReferences(current, fullNameSet, dependencies, diagnostics);
+            }
+
+            return RuntimeUtilities.EmitCompilationCore(compilation, manifestResources, diagnostics, testData);
+        }
+
+        internal static EmitOutput? EmitCompilationCore(
+            Compilation compilation,
+            IEnumerable<ResourceDescription> manifestResources,
+            DiagnosticBag diagnostics,
+            CompilationTestData testData
+        )
+        {
+            using (var executableStream = new MemoryStream())
+            {
+                var pdb = default(ImmutableArray<byte>);
+                var assembly = default(ImmutableArray<byte>);
+                var pdbStream = MonoHelpers.IsRunningOnMono()
+                    ? null
+                    : new MemoryStream();
+
+                EmitResult result;
+                try
+                {
+                    result = compilation.Emit(
+                        executableStream,
+                        pdbStream: pdbStream,
+                        xmlDocumentationStream: null,
+                        win32Resources: null,
+                        manifestResources: manifestResources,
+                        options: EmitOptions.Default,
+                        debugEntryPoint: null,
+                        testData: testData,
+                        getHostDiagnostics: null,
+                        cancellationToken: default(CancellationToken));
+                }
+                finally
+                {
+                    if (pdbStream != null)
+                    {
+                        pdb = pdbStream.ToImmutable();
+                        pdbStream.Dispose();
+                    }
+                }
+
+                diagnostics.AddRange(result.Diagnostics);
+                assembly = executableStream.ToImmutable();
+
+                if (result.Success)
+                {
+                    return new EmitOutput(assembly, pdb);
+                }
+
+                return null;
+            }
+        }
+
+
+        public static string DumpAssemblyData(IEnumerable<ModuleData> modules, out string dumpDirectory)
+        {
+            dumpDirectory = null;
+
+            StringBuilder sb = new StringBuilder();
+            foreach (var module in modules)
+            {
+                // Limit the number of dumps to 10.  After 10 we're likely in a bad state and are 
+                // dumping lots of unnecessary data.
+                if (s_dumpCount > 10)
+                {
+                    break;
+                }
+
+                if (module.InMemoryModule)
+                {
+                    Interlocked.Increment(ref s_dumpCount);
+
+                    if (dumpDirectory == null)
+                    {
+                        dumpDirectory = Path.GetTempPath();
+                        try
+                        {
+                            Directory.CreateDirectory(dumpDirectory);
+                        }
+                        catch
+                        {
+                            // Okay if directory already exists
+                        }
+                    }
+
+                    string fileName;
+                    if (module.Kind == OutputKind.NetModule)
+                    {
+                        fileName = module.FullName;
+                    }
+                    else
+                    {
+                        AssemblyIdentity identity;
+                        AssemblyIdentity.TryParseDisplayName(module.FullName, out identity);
+                        fileName = identity.Name;
+                    }
+
+                    string pePath = Path.Combine(dumpDirectory, fileName + module.Kind.GetDefaultExtension());
+                    string pdbPath = (module.Pdb != null) ? pdbPath = Path.Combine(dumpDirectory, fileName + ".pdb") : null;
+                    try
+                    {
+                        module.Image.WriteToFile(pePath);
+                        if (pdbPath != null)
+                        {
+                            module.Pdb.WriteToFile(pdbPath);
+                        }
+                    }
+                    catch (IOException)
+                    {
+                        pePath = "<unable to write file>";
+                        if (pdbPath != null)
+                        {
+                            pdbPath = "<unable to write file>";
+                        }
+                    }
+                    sb.Append("PE(" + module.Kind + "): ");
+                    sb.AppendLine(pePath);
+                    if (pdbPath != null)
+                    {
+                        sb.Append("PDB: ");
+                        sb.AppendLine(pdbPath);
+                    }
+                }
+            }
+            return sb.ToString();
+        }
+    }
+
+    public interface IRuntimeEnvironment : IDisposable
+    {
+        void Emit(Microsoft.CodeAnalysis.Compilation mainCompilation, IEnumerable<ResourceDescription> manifestResources, bool usePdbForDebugging = false);
+        int Execute(string moduleName, string expectedOutput);
+        ImmutableArray<byte> GetMainImage();
+        ImmutableArray<byte> GetMainPdb();
+        ImmutableArray<Diagnostic> GetDiagnostics();
+        SortedSet<string> GetMemberSignaturesFromMetadata(string fullyQualifiedTypeName, string memberName);
+        IList<ModuleData> GetAllModuleData();
+        void PeVerify();
+        string[] PeVerifyModules(string[] modulesToVerify, bool throwOnError = true);
+    }
+
+    internal interface IInternalRuntimeEnvironment
+    {
+        CompilationTestData GetCompilationTestData();
+    }
+}

src/Test/Utilities/Shared/ExceptionHelper.cs

+// Copyright (c) Microsoft.  All Rights Reserved.  Licensed under the Apache License, Version 2.0.  See License.txt in the project root for license information.
+
+using System;
+using System.Collections.Generic;
+using System.Text;
+using Microsoft.CodeAnalysis;
+
+namespace Roslyn.Test.Utilities
+{
+    internal static class ExceptionHelper
+    {
+        internal static string GetMessageFromResult(IEnumerable<Diagnostic> diagnostics, string directory)
+        {
+            StringBuilder sb = new StringBuilder();
+            sb.AppendLine("Emit Failed, binaries saved to: ");
+            sb.AppendLine(directory);
+            foreach (var d in diagnostics)
+            {
+                sb.AppendLine(d.ToString());
+            }
+            return sb.ToString();
+        }
+
+        internal static string GetMessageFromResult(string output, string exePath)
+        {
+            StringBuilder sb = new StringBuilder();
+            sb.AppendLine();
+            sb.Append("PeVerify failed for assembly '");
+            sb.Append(exePath);
+            sb.AppendLine("':");
+            sb.AppendLine(output);
+            return sb.ToString();
+        }
+
+        internal static string GetMessageFromException(Exception executionException, string exePath)
+        {
+            StringBuilder sb = new StringBuilder();
+            sb.AppendLine();
+            sb.Append("Execution failed for assembly '");
+            sb.Append(exePath);
+            sb.AppendLine("'.");
+            sb.Append("Exception: " + executionException);
+            return sb.ToString();
+        }
+
+        internal static string GetMessageFromResult(string expectedOutput, string actualOutput, string exePath)
+        {
+            StringBuilder sb = new StringBuilder();
+            sb.AppendLine();
+            sb.Append("Execution failed for assembly '");
+            sb.Append(exePath);
+            sb.AppendLine("'.");
+            if (expectedOutput != null)
+            {
+                sb.Append("Expected: ");
+                sb.AppendLine(expectedOutput);
+                sb.Append("Actual:   ");
+                sb.AppendLine(actualOutput);
+            }
+            else
+            {
+                sb.Append("Output: ");
+                sb.AppendLine(actualOutput);
+            }
+            return sb.ToString();
+        }
+    }
+}

src/Test/Utilities/Shared/TestUtilities.projitems

@@ -25,6 +25,7 @@
     <Compile Include="$(MSBuildThisFileDirectory)Compilation\CompilationExtensions.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)Compilation\CompilationOutputFiles.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)Compilation\CompilationTestDataExtensions.cs" />
+    <Compile Include="$(MSBuildThisFileDirectory)Compilation\IRuntimeEnvironment.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)Compilation\SpeculativeSemanticModelTestsBase.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)Compilation\TestOperationWalker.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)Compilation\VersionTestHelpers.cs" />
@@ -36,6 +37,7 @@
     <Compile Include="$(MSBuildThisFileDirectory)Diagnostics\TestDiagnosticAnalyzer.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)Diagnostics\ThrowingDiagnosticAnalyzer.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)Diagnostics\TrackingDiagnosticAnalyzer.cs" />
+    <Compile Include="$(MSBuildThisFileDirectory)ExceptionHelper.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)FX\ConsoleOutput.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)FX\CultureHelpers.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)FX\DirectoryHelper.cs" />

src/Workspaces/Core/Portable/Shared/Extensions/ICodeDefinitionFactoryExtensions.cs

@@ -4,6 +4,7 @@
 using System.Collections.Immutable;
 using System.Linq;
 using System.Threading;
+using System.Threading.Tasks;
 using Microsoft.CodeAnalysis.CodeGeneration;
 using Microsoft.CodeAnalysis.Editing;
 using Microsoft.CodeAnalysis.FindSymbols;
@@ -208,7 +209,7 @@ private static bool TryGetValue(IDictionary<string, ISymbol> dictionary, string
             }
         }
 
-        public static IPropertySymbol OverrideProperty(
+        public static async Task<IPropertySymbol> OverridePropertyAsync(
             this SyntaxGenerator codeFactory,
             IPropertySymbol overriddenProperty,
             DeclarationModifiers modifiers,
@@ -225,7 +226,8 @@ private static bool TryGetValue(IDictionary<string, ISymbol> dictionary, string
             // Implement an abstract property by throwing not implemented in accessors.
             if (overriddenProperty.IsAbstract)
             {
-                getBody = codeFactory.CreateThrowNotImplementStatement(document.Project.GetCompilationAsync(cancellationToken).WaitAndGetResult(cancellationToken));
+                var compilation = await document.Project.GetCompilationAsync(cancellationToken).ConfigureAwait(false);
+                getBody = codeFactory.CreateThrowNotImplementStatement(compilation);
                 setBody = getBody;
             }
             else if (overriddenProperty.IsIndexer() && document.Project.Language == LanguageNames.CSharp)
@@ -247,8 +249,8 @@ private static bool TryGetValue(IDictionary<string, ISymbol> dictionary, string
             {
                 // Call accessors directly if C# overriding VB
                 if (document.Project.Language == LanguageNames.CSharp
-                    && SymbolFinder.FindSourceDefinitionAsync(overriddenProperty, document.Project.Solution, cancellationToken)
-                                    .WaitAndGetResult(CancellationToken.None).Language == LanguageNames.VisualBasic)
+                    && (await SymbolFinder.FindSourceDefinitionAsync(overriddenProperty, document.Project.Solution, cancellationToken).ConfigureAwait(false))
+                        .Language == LanguageNames.VisualBasic)
                 {
                     var getName = overriddenProperty.GetMethod != null ? overriddenProperty.GetMethod.Name : null;
                     var setName = overriddenProperty.SetMethod != null ? overriddenProperty.SetMethod.Name : null;
@@ -351,7 +353,7 @@ private static bool TryGetValue(IDictionary<string, ISymbol> dictionary, string
                 name: overriddenEvent.Name);
         }
 
-        public static IMethodSymbol OverrideMethod(
+        public static async Task<IMethodSymbol> OverrideMethodAsync(
             this SyntaxGenerator codeFactory,
             IMethodSymbol overriddenMethod,
             DeclarationModifiers modifiers,
@@ -362,11 +364,12 @@ private static bool TryGetValue(IDictionary<string, ISymbol> dictionary, string
             // Abstract: Throw not implemented
             if (overriddenMethod.IsAbstract)
             {
+                var compilation = await newDocument.Project.GetCompilationAsync(cancellationToken).ConfigureAwait(false);
                 return CodeGenerationSymbolFactory.CreateMethodSymbol(
                     overriddenMethod,
                     accessibility: overriddenMethod.ComputeResultantAccessibility(newContainingType),
                     modifiers: modifiers,
-                    statements: new[] { codeFactory.CreateThrowNotImplementStatement(newDocument.Project.GetCompilationAsync(cancellationToken).WaitAndGetResult(cancellationToken)) });
+                    statements: new[] { codeFactory.CreateThrowNotImplementStatement(compilation) });
             }
             else
             {