Add resolvers to misc workspace script projects

src/EditorFeatures/Core/Implementation/ReferenceHighlighting/AbstractDocumentHighlightsService.cs

@@ -186,7 +186,7 @@ private bool ShouldConsiderSymbol(ISymbol symbol)
                             // Document once https://github.com/dotnet/roslyn/issues/5260 is fixed.
                             if (document == null)
                             {
-                                Debug.Assert(solution.Workspace.Kind == "Interactive");
+                                Debug.Assert(solution.Workspace.Kind == WorkspaceKind.Interactive || solution.Workspace.Kind == WorkspaceKind.MiscellaneousFiles);
                                 continue;
                             }
 

src/VisualStudio/CSharp/Impl/CSharpPackage.cs

@@ -163,8 +163,7 @@ protected override void RegisterMiscellaneousFilesWorkspaceInformation(Miscellan
             miscellaneousFilesWorkspace.RegisterLanguage(
                 Guids.CSharpLanguageServiceId,
                 LanguageNames.CSharp,
-                ".csx",
-                CSharpParseOptions.Default);
+                ".csx");
         }
 
         protected override string RoslynLanguageName

src/VisualStudio/Core/Def/Implementation/ProjectSystem/MiscellaneousFilesWorkspace.HostProject.cs

@@ -20,22 +20,24 @@ private sealed class HostProject : IVisualStudioHostProject
             internal IVisualStudioHostDocument Document { get; set; }
 
             private readonly string _assemblyName;
-            private readonly ParseOptions _parseOptions;
+            private readonly ParseOptions _parseOptionsOpt;
+            private readonly CompilationOptions _compilationOptionsOpt;
             private readonly IEnumerable<MetadataReference> _metadataReferences;
             private readonly VersionStamp _version;
             private readonly Workspace _workspace;
 
-            public HostProject(Workspace workspace, SolutionId solutionId, string languageName, ParseOptions parseOptions, IEnumerable<MetadataReference> metadataReferences)
+            public HostProject(Workspace workspace, SolutionId solutionId, string languageName, ParseOptions parseOptionsOpt, CompilationOptions compilationOptionsOpt, IEnumerable<MetadataReference> metadataReferences)
             {
                 Debug.Assert(workspace != null);
                 Debug.Assert(languageName != null);
-                Debug.Assert(parseOptions != null);
                 Debug.Assert(metadataReferences != null);
 
                 _workspace = workspace;
-                this.Id = ProjectId.CreateNewId(debugName: "Miscellaneous Files");
-                this.Language = languageName;
-                _parseOptions = parseOptions;
+                _parseOptionsOpt = parseOptionsOpt;
+                _compilationOptionsOpt = compilationOptionsOpt;
+
+                Id = ProjectId.CreateNewId(debugName: "Miscellaneous Files");
+                Language = languageName;
 
                 // the assembly name must be unique for each collection of loose files.  since the name doesn't matter
                 // a random GUID can be used.
@@ -48,14 +50,14 @@ public HostProject(Workspace workspace, SolutionId solutionId, string languageNa
             public ProjectInfo CreateProjectInfoForCurrentState()
             {
                 var info = ProjectInfo.Create(
-                    this.Id,
+                    Id,
                     _version,
                     name: ServicesVSResources.Miscellaneous_Files,
                     assemblyName: _assemblyName,
-                    language: this.Language,
+                    language: Language,
                     filePath: null,
-                    compilationOptions: null, // we don't have compilation options?
-                    parseOptions: _parseOptions,
+                    compilationOptions: _compilationOptionsOpt,
+                    parseOptions: _parseOptionsOpt,
                     documents: SpecializedCollections.EmptyEnumerable<DocumentInfo>(),
                     projectReferences: SpecializedCollections.EmptyEnumerable<ProjectReference>(),
                     metadataReferences: _metadataReferences,

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

@@ -16,6 +16,7 @@
 using Roslyn.Utilities;
 using Microsoft.CodeAnalysis.Editor.Shared.Utilities;
 using System.Threading.Tasks;
+using Microsoft.CodeAnalysis.Host;
 
 namespace Microsoft.VisualStudio.LanguageServices.Implementation.ProjectSystem
 {
@@ -68,9 +69,9 @@ internal sealed partial class MiscellaneousFilesWorkspace : Workspace, IVsRunnin
             saveEventsService.StartSendingSaveEvents();
         }
 
-        public void RegisterLanguage(Guid languageGuid, string languageName, string scriptExtension, ParseOptions parseOptions)
+        public void RegisterLanguage(Guid languageGuid, string languageName, string scriptExtension)
         {
-            _languageInformationByLanguageGuid.Add(languageGuid, new LanguageInformation(languageName, scriptExtension, parseOptions));
+            _languageInformationByLanguageGuid.Add(languageGuid, new LanguageInformation(languageName, scriptExtension));
         }
 
         internal void StartSolutionCrawler()
@@ -328,21 +329,46 @@ private void AttachToDocument(uint docCookie, string moniker)
             // This should always succeed since we only got here if we already confirmed the moniker is acceptable
             var languageInformation = TryGetLanguageInformation(moniker);
             Contract.ThrowIfNull(languageInformation);
-            var parseOptions = languageInformation.ParseOptions;
 
-            if (Path.GetExtension(moniker) == languageInformation.ScriptExtension)
+            var languageServices = Services.GetLanguageServices(languageInformation.LanguageName);
+            var compilationOptionsOpt = languageServices.GetService<ICompilationFactoryService>()?.GetDefaultCompilationOptions();
+            var parseOptionsOpt = languageServices.GetService<ISyntaxTreeFactoryService>()?.GetDefaultParseOptions();
+
+            if (parseOptionsOpt != null && 
+                compilationOptionsOpt != null &&
+                PathUtilities.GetExtension(moniker) == languageInformation.ScriptExtension)
             {
-                parseOptions = parseOptions.WithKind(SourceCodeKind.Script);
+                parseOptionsOpt = parseOptionsOpt.WithKind(SourceCodeKind.Script);
+
+                var metadataService = Services.GetService<IMetadataService>();
+                var directory = PathUtilities.GetDirectoryName(moniker);
+
+                // TODO (https://github.com/dotnet/roslyn/issues/5325, https://github.com/dotnet/roslyn/issues/13886): 
+                // - Need to have a way to specify these somewhere in VS options.
+                // - Use RuntimeMetadataReferenceResolver like in InteractiveEvaluator.CreateMetadataReferenceResolver
+                // - Add default namespace imports
+                // - Add default script globals available in 'csi foo.csx' environment: CommandLineScriptGlobals
+
+                var referenceSearchPaths = ImmutableArray<string>.Empty;
+                var sourceSearchPaths = ImmutableArray<string>.Empty;
+
+                var referenceResolver = new WorkspaceMetadataFileReferenceResolver(
+                    metadataService,
+                    new RelativePathResolver(referenceSearchPaths, directory));
+
+                compilationOptionsOpt = compilationOptionsOpt.
+                    WithMetadataReferenceResolver(referenceResolver).
+                    WithSourceReferenceResolver(new SourceFileResolver(sourceSearchPaths, directory));
             }
 
             // First, create the project
-            var hostProject = new HostProject(this, CurrentSolution.Id, languageInformation.LanguageName, parseOptions, _metadataReferences);
+            var hostProject = new HostProject(this, CurrentSolution.Id, languageInformation.LanguageName, parseOptionsOpt, compilationOptionsOpt, _metadataReferences);
 
             // Now try to find the document. We accept any text buffer, since we've already verified it's an appropriate file in ShouldIncludeFile.
             var document = _documentProvider.TryGetDocumentForFile(
                 hostProject,
                 moniker,
-                parseOptions.Kind,
+                parseOptionsOpt?.Kind ?? SourceCodeKind.Regular,
                 getFolderNames: _ => SpecializedCollections.EmptyReadOnlyList<string>(),
                 canUseTextBuffer: _ => true);
 
@@ -453,16 +479,14 @@ void IVisualStudioHostProjectContainer.NotifyNonDocumentOpenedForProject(IVisual
 
         private class LanguageInformation
         {
-            public LanguageInformation(string languageName, string scriptExtension, ParseOptions parseOptions)
+            public LanguageInformation(string languageName, string scriptExtension)
             {
                 this.LanguageName = languageName;
                 this.ScriptExtension = scriptExtension;
-                this.ParseOptions = parseOptions;
             }
 
             public string LanguageName { get; }
             public string ScriptExtension { get; }
-            public ParseOptions ParseOptions { get; }
         }
     }
 }

src/VisualStudio/VisualBasic/Impl/LanguageService/VisualBasicPackage.vb

@@ -156,8 +156,7 @@ Namespace Microsoft.VisualStudio.LanguageServices.VisualBasic
             miscellaneousFilesWorkspace.RegisterLanguage(
                 Guids.VisualBasicLanguageServiceId,
                 LanguageNames.VisualBasic,
-                ".vbx",
-                VisualBasicParseOptions.Default)
+                ".vbx")
         End Sub
 
         Protected Overrides ReadOnly Property RoslynLanguageName As String

src/Workspaces/Core/Portable/FindSymbols/FindReferences/Finders/LinkedFileReferenceFinder.cs

@@ -26,7 +26,7 @@ internal class LinkedFileReferenceFinder : IReferenceFinder
                 // Document once https://github.com/dotnet/roslyn/issues/5260 is fixed.
                 if (originalDocument == null)
                 {
-                    Debug.Assert(solution.Workspace.Kind == "Interactive");
+                    Debug.Assert(solution.Workspace.Kind == WorkspaceKind.Interactive || solution.Workspace.Kind == WorkspaceKind.MiscellaneousFiles);
                     continue;
                 }
 

src/Workspaces/Core/Portable/SemanticModelWorkspaceService/SemanticModelWorkspaceServiceFactory.cs

@@ -473,8 +473,8 @@ private CompilationSet(VersionStamp version, ValueSource<Compilation> compilatio
                         // Document once https://github.com/dotnet/roslyn/issues/5260 is fixed.
                         if (documentId == null)
                         {
-                            Debug.Assert(newProject.Solution.Workspace.Kind == "Interactive");
-                            continue;
+                            Debug.Assert(newProject.Solution.Workspace.Kind == WorkspaceKind.Interactive || newProject.Solution.Workspace.Kind == WorkspaceKind.MiscellaneousFiles);
+                            continue;                                
                         }
 
                         map = map.SetItem(documentId, newTree);