Merge pull request #37594 from...

Merge pull request #37594 from jasonmalinowski/add-nullable-annotations-to-speculative-model-creation

Add nullable annotations to speculative model creation and update code for bug found

src/Workspaces/Core/Portable/SemanticModelWorkspaceService/ISemanticModelService.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.
 
+#nullable enable
+
 using System.Threading;
 using System.Threading.Tasks;
 using Microsoft.CodeAnalysis.Host;

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

@@ -40,12 +40,14 @@ private class SemanticModelService : ISemanticModelService
 
             private readonly ReaderWriterLockSlim _gate = new ReaderWriterLockSlim(LockRecursionPolicy.NoRecursion);
 
+#nullable enable
+
             public async Task<SemanticModel> GetSemanticModelForNodeAsync(Document document, SyntaxNode node, CancellationToken cancellationToken = default)
             {
                 var syntaxFactsService = document.GetLanguageService<ISyntaxFactsService>();
                 var semanticFactsService = document.GetLanguageService<ISemanticFactsService>();
 
-                if (syntaxFactsService == null || semanticFactsService == null || node == null)
+                if (syntaxFactsService == null || semanticFactsService == null)
                 {
                     // it only works if we can track member
                     return await document.GetSemanticModelAsync(cancellationToken).ConfigureAwait(false);
@@ -160,6 +162,8 @@ private bool IsPrimaryBranch(Document document)
                 return document.Project.Solution.BranchId == document.Project.Solution.Workspace.PrimaryBranchId;
             }
 
+#nullable restore
+
             private Task AddVersionCacheAsync(Project project, VersionStamp version, CancellationToken cancellationToken)
             {
                 return UpdateVersionCacheAsync(project, version, primarySet: null, cancellationToken: cancellationToken);

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

@@ -33,6 +33,8 @@ public static bool IsOpen(this Document document)
             return workspace != null && workspace.IsDocumentOpen(document.Id);
         }
 
+#nullable enable
+
         /// <summary>
         /// this will return either regular semantic model or speculative semantic based on context. 
         /// any feature that is involved in typing or run on UI thread should use this to take advantage of speculative semantic model 
@@ -60,7 +62,7 @@ public static async Task<SemanticModel> GetSemanticModelForSpanAsync(this Docume
                 return await document.GetSemanticModelAsync(cancellationToken).ConfigureAwait(false);
             }
 
-            var node = token.Parent.AncestorsAndSelf().FirstOrDefault(a => a.FullSpan.Contains(span));
+            var node = token.Parent.AncestorsAndSelf().First(a => a.FullSpan.Contains(span));
             return await GetSemanticModelForNodeAsync(semanticModelService, syntaxFactService, document, node, span, cancellationToken).ConfigureAwait(false);
         }
 
@@ -75,7 +77,7 @@ public static async Task<SemanticModel> GetSemanticModelForSpanAsync(this Docume
         /// also, symbols from the semantic model returned by this API might have out of date location information. 
         /// if exact location (not relative location) is needed from symbol, regular GetSemanticModel should be used.
         /// </summary>
-        public static Task<SemanticModel> GetSemanticModelForNodeAsync(this Document document, SyntaxNode node, CancellationToken cancellationToken)
+        public static Task<SemanticModel> GetSemanticModelForNodeAsync(this Document document, SyntaxNode? node, CancellationToken cancellationToken)
         {
             var syntaxFactService = document.GetLanguageService<ISyntaxFactsService>();
             var semanticModelService = document.Project.Solution.Workspace.Services.GetService<ISemanticModelService>();
@@ -101,6 +103,8 @@ public static Task<SemanticModel> GetSemanticModelForNodeAsync(this Document doc
             return semanticModelService.GetSemanticModelForNodeAsync(document, node, cancellationToken);
         }
 
+#nullable restore
+
 #if DEBUG
         public static async Task<bool> HasAnyErrorsAsync(this Document document, CancellationToken cancellationToken, List<string> ignoreErrorCode = null)
         {