Updates included build tool to match the current 6.0.200 sdk

build.cake

@@ -514,6 +514,10 @@ Task("CreateMSBuildFolder")
         source: CombinePaths(env.Folders.Tools, "SQLitePCLRaw.bundle_green", "lib", "netstandard2.0", "SQLitePCLRaw.batteries_v2.dll"),
         destination: CombinePaths(msbuildCurrentBinTargetFolder, "SQLitePCLRaw.batteries_v2.dll"),
         overwrite: true);
+
+    FileHelper.Copy(
+        source: CombinePaths(env.Folders.Tools, "Microsoft.IO.Redist", "lib", "net472", "Microsoft.IO.Redist.dll"),
+        destination: CombinePaths(msbuildCurrentBinTargetFolder, "Microsoft.IO.Redist.dll"));
 });
 
 /// <summary>

build/Packages.props

@@ -7,7 +7,7 @@
         <MicrosoftTestPackageVersion>17.0.0</MicrosoftTestPackageVersion>
         <MSBuildPackageVersion>17.0.0</MSBuildPackageVersion>
         <NuGetPackageVersion>6.0.0</NuGetPackageVersion>
-        <RoslynPackageVersion>4.0.1-1.22053.6</RoslynPackageVersion>
+        <RoslynPackageVersion>4.1.0-3.22069.8</RoslynPackageVersion>
         <XunitPackageVersion>2.4.1</XunitPackageVersion>
     </PropertyGroup>
 

src/OmniSharp.Abstractions/Configuration.cs

@@ -4,7 +4,7 @@ internal static class Configuration
     {
         public static bool ZeroBasedIndices = false;
 
-        public const string RoslynVersion = "4.0.0.0";
+        public const string RoslynVersion = "4.1.0.0";
         public const string RoslynPublicKeyToken = "31bf3856ad364e35";
 
         public readonly static string RoslynFeatures = GetRoslynAssemblyFullName("Microsoft.CodeAnalysis.Features");

src/OmniSharp.Host/MSBuild/Discovery/MSBuildLocator.cs

@@ -70,6 +70,17 @@ public void RegisterInstance(MSBuildInstance instance)
 
             RegisteredInstance = instance ?? throw new ArgumentNullException(nameof(instance));
 
+            if (instance.DiscoveryType == DiscoveryType.StandAlone)
+            {
+                // MSBuild began relying on the Microsoft.IO.Redist library which does not work
+                // on MacOS or Linux platforms. Disabling the 17.0 feature wave opts us in to the
+                // earlier behavior of using System.IO.
+
+                // This issue only affects the MSBuild tools shipped with O# as Mono does not ship
+                // with a version of MSBuild that includes this change.
+                Environment.SetEnvironmentVariable("MSBUILDDISABLEFEATURESFROMVERSION", "17.0");
+            }
+
             if (instance.SetMSBuildExePathVariable)
             {
                 var msbuildExePath = Path.Combine(instance.MSBuildPath, "MSBuild.exe");

src/OmniSharp.Http.Driver/app.config

@@ -7,23 +7,23 @@
         <assemblyBinding xmlns="urn:schemas-microsoft-com:asm.v1">
             <dependentAssembly>
                 <assemblyIdentity name="Microsoft.CodeAnalysis" publicKeyToken="31bf3856ad364e35" culture="neutral"/>
-                <bindingRedirect oldVersion="0.0.0.0-4.0.0.0" newVersion="4.0.0.0"/>
+                <bindingRedirect oldVersion="0.0.0.0-4.1.0.0" newVersion="4.1.0.0"/>
             </dependentAssembly>
             <dependentAssembly>
                 <assemblyIdentity name="Microsoft.CodeAnalysis.CSharp" publicKeyToken="31bf3856ad364e35" culture="neutral"/>
-                <bindingRedirect oldVersion="0.0.0.0-4.0.0.0" newVersion="4.0.0.0"/>
+                <bindingRedirect oldVersion="0.0.0.0-4.1.0.0" newVersion="4.1.0.0"/>
             </dependentAssembly>
             <dependentAssembly>
                 <assemblyIdentity name="Microsoft.CodeAnalysis.Workspaces" publicKeyToken="31bf3856ad364e35" culture="neutral"/>
-                <bindingRedirect oldVersion="0.0.0.0-4.0.0.0" newVersion="4.0.0.0"/>
+                <bindingRedirect oldVersion="0.0.0.0-4.1.0.0" newVersion="4.1.0.0"/>
             </dependentAssembly>
             <dependentAssembly>
                 <assemblyIdentity name="Microsoft.CodeAnalysis.Features" publicKeyToken="31bf3856ad364e35" culture="neutral"/>
-                <bindingRedirect oldVersion="0.0.0.0-4.0.0.0" newVersion="4.0.0.0"/>
+                <bindingRedirect oldVersion="0.0.0.0-4.1.0.0" newVersion="4.1.0.0"/>
             </dependentAssembly>
             <dependentAssembly>
                 <assemblyIdentity name="Microsoft.CodeAnalysis.CSharp.Features" publicKeyToken="31bf3856ad364e35" culture="neutral"/>
-                <bindingRedirect oldVersion="0.0.0.0-4.0.0.0" newVersion="4.0.0.0"/>
+                <bindingRedirect oldVersion="0.0.0.0-4.1.0.0" newVersion="4.1.0.0"/>
             </dependentAssembly>
             <dependentAssembly>
                 <assemblyIdentity name="System.Threading.Tasks.Dataflow" publicKeyToken="b03f5f7f11d50a3a" culture="neutral" />

src/OmniSharp.LanguageServerProtocol/Handlers/OmniSharpCompletionHandler.cs

@@ -114,7 +114,17 @@ private static void VerifyEnumsInSync(Type enum1, Type enum2)
             Debug.Assert(lspValues.Length == modelValues.Length);
             for (int i = 0; i < lspValues.Length; i++)
             {
-                Debug.Assert((int?)lspValues.GetValue(i) == (int?)modelValues.GetValue(i));
+                var lspValue = lspValues.GetValue(i);
+                var modelValue = modelValues.GetValue(i);
+
+                if (lspValue is null || modelValue is null)
+                {
+                    Debug.Assert(lspValue is null && modelValue is null);
+                }
+                else
+                {
+                    Debug.Assert((int)lspValue == (int)modelValue);
+                }
             }
         }
 

src/OmniSharp.LanguageServerProtocol/app.config

@@ -7,23 +7,23 @@
         <assemblyBinding xmlns="urn:schemas-microsoft-com:asm.v1">
             <dependentAssembly>
                 <assemblyIdentity name="Microsoft.CodeAnalysis" publicKeyToken="31bf3856ad364e35" culture="neutral"/>
-                <bindingRedirect oldVersion="0.0.0.0-4.0.0.0" newVersion="4.0.0.0"/>
+                <bindingRedirect oldVersion="0.0.0.0-4.1.0.0" newVersion="4.1.0.0"/>
             </dependentAssembly>
             <dependentAssembly>
                 <assemblyIdentity name="Microsoft.CodeAnalysis.CSharp" publicKeyToken="31bf3856ad364e35" culture="neutral"/>
-                <bindingRedirect oldVersion="0.0.0.0-4.0.0.0" newVersion="4.0.0.0"/>
+                <bindingRedirect oldVersion="0.0.0.0-4.1.0.0" newVersion="4.1.0.0"/>
             </dependentAssembly>
             <dependentAssembly>
                 <assemblyIdentity name="Microsoft.CodeAnalysis.Workspaces" publicKeyToken="31bf3856ad364e35" culture="neutral"/>
-                <bindingRedirect oldVersion="0.0.0.0-4.0.0.0" newVersion="4.0.0.0"/>
+                <bindingRedirect oldVersion="0.0.0.0-4.1.0.0" newVersion="4.1.0.0"/>
             </dependentAssembly>
             <dependentAssembly>
                 <assemblyIdentity name="Microsoft.CodeAnalysis.Features" publicKeyToken="31bf3856ad364e35" culture="neutral"/>
-                <bindingRedirect oldVersion="0.0.0.0-4.0.0.0" newVersion="4.0.0.0"/>
+                <bindingRedirect oldVersion="0.0.0.0-4.1.0.0" newVersion="4.1.0.0"/>
             </dependentAssembly>
             <dependentAssembly>
                 <assemblyIdentity name="Microsoft.CodeAnalysis.CSharp.Features" publicKeyToken="31bf3856ad364e35" culture="neutral"/>
-                <bindingRedirect oldVersion="0.0.0.0-4.0.0.0" newVersion="4.0.0.0"/>
+                <bindingRedirect oldVersion="0.0.0.0-4.1.0.0" newVersion="4.1.0.0"/>
             </dependentAssembly>
             <dependentAssembly>
                 <assemblyIdentity name="System.Threading.Tasks.Dataflow" publicKeyToken="b03f5f7f11d50a3a" culture="neutral" />

src/OmniSharp.Roslyn.CSharp/Services/Completion/CompletionListBuilder.cs

@@ -64,7 +64,7 @@ internal static partial class CompletionListBuilder
         internal const string XmlDocCommentCompletionProvider = "Microsoft.CodeAnalysis.CSharp.Completion.Providers.XmlDocCommentCompletionProvider";
         internal const string TypeImportCompletionProvider = "Microsoft.CodeAnalysis.CSharp.Completion.Providers.TypeImportCompletionProvider";
         internal const string ExtensionMethodImportCompletionProvider = "Microsoft.CodeAnalysis.CSharp.Completion.Providers.ExtensionMethodImportCompletionProvider";
-        internal const string EmeddedLanguageCompletionProvider = "Microsoft.CodeAnalysis.CSharp.Completion.Providers.EmbeddedLanguageCompletionProvider";
+        internal const string AggregateEmeddedLanguageCompletionProvider = "Microsoft.CodeAnalysis.CSharp.Completion.Providers.AggregateEmbeddedLanguageCompletionProvider";
 
         internal static async Task<(IReadOnlyList<CompletionItem>, bool)> BuildCompletionItems(
             Document document,

src/OmniSharp.Roslyn.CSharp/Services/Completion/CompletionService.cs

@@ -22,6 +22,8 @@
 using CompletionItem = OmniSharp.Models.v1.Completion.CompletionItem;
 using CompletionTriggerKind = OmniSharp.Models.v1.Completion.CompletionTriggerKind;
 using CSharpCompletionService = Microsoft.CodeAnalysis.Completion.CompletionService;
+using System.Threading;
+using Roslyn.Utilities;
 
 namespace OmniSharp.Roslyn.CSharp.Services.Completion
 {
@@ -65,22 +67,25 @@ public async Task<CompletionResponse> Handle(CompletionRequest request)
             var position = sourceText.GetTextPosition(request);
 
             var completionService = CSharpCompletionService.GetService(document);
-            Debug.Assert(request.TriggerCharacter != null || request.CompletionTrigger != CompletionTriggerKind.TriggerCharacter);
+            RoslynDebug.Assert(completionService != null);
+            RoslynDebug.Assert(request.TriggerCharacter != null || request.CompletionTrigger != CompletionTriggerKind.TriggerCharacter);
 
             CompletionTrigger trigger = request.CompletionTrigger switch
             {
                 CompletionTriggerKind.TriggerCharacter when request.TriggerCharacter is char c => CompletionTrigger.CreateInsertionTrigger(c),
                 _ => CompletionTrigger.Invoke,
             };
 
+            var options = new OmniSharpCompletionOptions(ShowItemsFromUnimportedNamespaces: _omniSharpOptions.RoslynExtensionsOptions.EnableImportCompletion);
+
             if (request.CompletionTrigger == CompletionTriggerKind.TriggerCharacter &&
-                !completionService.ShouldTriggerCompletion(sourceText, position, trigger))
+                !await OmniSharpCompletionService.ShouldTriggerCompletionAsync(completionService, document, position, trigger, roles: null, options, CancellationToken.None))
             {
                 _logger.LogTrace("Should not insert completions here.");
                 return new CompletionResponse { Items = ImmutableArray<CompletionItem>.Empty };
             }
 
-            var (completions, expandedItemsAvailable) = await OmniSharpCompletionService.GetCompletionsAsync(completionService, document, position, trigger);
+            var (completions, expandedItemsAvailable) = await OmniSharpCompletionService.GetCompletionsAsync(completionService, document, position, trigger, roles: null, options, CancellationToken.None);
             _logger.LogTrace("Found {0} completions for {1}:{2},{3}",
                              completions?.Items.IsDefaultOrEmpty != false ? 0 : completions.Items.Length,
                              request.FileName,
@@ -114,7 +119,7 @@ CompletionListBuilder.PartialMethodCompletionProvider or
             // that completion provider is still creating the cache. We'll mark this completion list as not completed, and the
             // editor will ask again when the user types more. By then, hopefully the cache will have populated and we can mark
             // the completion as done.
-            bool expectingImportedItems = expandedItemsAvailable && _workspace.Options.GetOption(OmniSharpCompletionService.ShowItemsFromUnimportedNamespaces, LanguageNames.CSharp) == true;
+            bool expectingImportedItems = expandedItemsAvailable && _omniSharpOptions.RoslynExtensionsOptions.EnableImportCompletion;
             var syntax = await document.GetSyntaxTreeAsync();
 
             var replacingSpanStartPosition = sourceText.Lines.GetLinePosition(typedSpan.Start);
@@ -150,7 +155,7 @@ public async Task<CompletionResolveResponse> Handle(CompletionResolveRequest req
                 return new CompletionResolveResponse { Item = request.Item };
             }
 
-            var (_, document, position, completions) = cachedList;
+            var (_, document, _, completions) = cachedList;
             var index = request.Item.Data.Index;
 
             if (request.Item is null
@@ -169,14 +174,17 @@ public async Task<CompletionResolveResponse> Handle(CompletionResolveRequest req
             }
 
             var completionService = CSharpCompletionService.GetService(document);
+            RoslynDebug.Assert(completionService != null);
+
             var description = await completionService.GetDescriptionAsync(document, lastCompletionItem);
+            RoslynDebug.Assert(description != null);
 
             var textBuilder = new StringBuilder();
             MarkdownHelpers.TaggedTextToMarkdown(description.TaggedParts, textBuilder, _formattingOptions, MarkdownFormat.FirstLineAsCSharp, out _);
 
             request.Item.Documentation = textBuilder.ToString();
 
-            string providerName = lastCompletionItem.GetProviderName();
+            var providerName = lastCompletionItem.GetProviderName();
             switch (providerName)
             {
                 case CompletionListBuilder.ExtensionMethodImportCompletionProvider:
@@ -243,6 +251,7 @@ public async Task<CompletionAfterInsertResponse> Handle(CompletionAfterInsertReq
             }
 
             var completionService = CSharpCompletionService.GetService(document);
+            RoslynDebug.Assert(completionService != null);
 
             // Get a document with change from the completion inserted, so that we can resolve the completion and get the
             // final full change.

src/OmniSharp.Roslyn.CSharp/Services/Intellisense/CompletionItemExtensions.cs

@@ -84,7 +84,7 @@ public static AutoCompleteResponse ToAutoCompleteResponse(this CompletionItem it
 
             // if provider name is "Microsoft.CodeAnalysis.CSharp.Completion.Providers.EmbeddedLanguageCompletionProvider"
             // we have access to more elaborate description
-            if (item.GetProviderName() == CompletionListBuilder.EmeddedLanguageCompletionProvider)
+            if (item.GetProviderName() == CompletionListBuilder.AggregateEmeddedLanguageCompletionProvider)
             {
                 response.DisplayText = item.InlineDescription;
                 if (item.Properties.TryGetValue("DescriptionKey", out var description))

src/OmniSharp.Roslyn.CSharp/Services/Intellisense/IntellisenseService.cs

@@ -15,6 +15,7 @@
 using OmniSharp.Roslyn.CSharp.Services.Documentation;
 using OmniSharp.Roslyn.CSharp.Services.Completion;
 using CompletionService = Microsoft.CodeAnalysis.Completion.CompletionService;
+using System.Threading;
 
 namespace OmniSharp.Roslyn.CSharp.Services.Intellisense
 {
@@ -23,13 +24,17 @@ namespace OmniSharp.Roslyn.CSharp.Services.Intellisense
     public class IntellisenseService : IRequestHandler<AutoCompleteRequest, IEnumerable<AutoCompleteResponse>>
     {
         private readonly OmniSharpWorkspace _workspace;
+
         private readonly FormattingOptions _formattingOptions;
 
+        private readonly OmniSharpOptions _omniSharpOptions;
+
         [ImportingConstructor]
-        public IntellisenseService(OmniSharpWorkspace workspace, FormattingOptions formattingOptions)
+        public IntellisenseService(OmniSharpWorkspace workspace, FormattingOptions formattingOptions, OmniSharpOptions omniSharpOptions)
         {
             _workspace = workspace;
             _formattingOptions = formattingOptions;
+            _omniSharpOptions = omniSharpOptions;
         }
 
         public async Task<IEnumerable<AutoCompleteResponse>> Handle(AutoCompleteRequest request)
@@ -43,7 +48,8 @@ public async Task<IEnumerable<AutoCompleteResponse>> Handle(AutoCompleteRequest
                 var sourceText = await document.GetTextAsync();
                 var position = sourceText.GetTextPosition(request);
                 var service = CompletionService.GetService(document);
-                var completionList = await service.GetCompletionsAsync(document, position);
+                var options = new OmniSharpCompletionOptions(ShowItemsFromUnimportedNamespaces: _omniSharpOptions.RoslynExtensionsOptions.EnableImportCompletion);
+                var (completionList, expandedItemsAvailable) = await OmniSharpCompletionService.GetCompletionsAsync(service, document, position, trigger: default, roles: null, options, CancellationToken.None);
 
                 if (completionList != null)
                 {

src/OmniSharp.Roslyn.CSharp/Services/Structure/BlockStructureService.cs

@@ -33,7 +33,11 @@ public async Task<BlockStructureResponse> Handle(BlockStructureRequest request)
 
             var text = await document.GetTextAsync();
 
-            var structure = await OmniSharpBlockStructureService.GetBlockStructureAsync(document, CancellationToken.None);
+            var options = new OmniSharpBlockStructureOptions(
+                ShowBlockStructureGuidesForCommentsAndPreprocessorRegions: true,
+                ShowOutliningForCommentsAndPreprocessorRegions: true);
+
+            var structure = await OmniSharpBlockStructureService.GetBlockStructureAsync(document, options, CancellationToken.None);
 
             var outliningSpans = new List<CodeFoldingBlock>();
             foreach (var span in structure.Spans)

src/OmniSharp.Roslyn/Utilities/Debug.cs

@@ -0,0 +1,28 @@
+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+// See the LICENSE file in the project root for more information.
+
+using System;
+using System.Diagnostics;
+using System.Diagnostics.CodeAnalysis;
+
+namespace Roslyn.Utilities
+{
+    internal static class RoslynDebug
+    {
+        /// <inheritdoc cref="Debug.Assert(bool)"/>
+        [Conditional("DEBUG")]
+        public static void Assert([DoesNotReturnIf(false)] bool b) => Debug.Assert(b);
+
+        /// <inheritdoc cref="Debug.Assert(bool, string)"/>
+        [Conditional("DEBUG")]
+        public static void Assert([DoesNotReturnIf(false)] bool b, string message)
+            => Debug.Assert(b, message);
+
+        [Conditional("DEBUG")]
+        public static void AssertNotNull<T>([NotNull] T value)
+        {
+            Assert(value is object, "Unexpected null reference");
+        }
+    }
+}