Add annotations for case correction types

src/Workspaces/CSharp/Portable/CaseCorrection/CSharpCaseCorrectionService.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.Collections.Concurrent;
 using System.Collections.Immutable;
 using System.Composition;
@@ -19,7 +21,7 @@ public CSharpCaseCorrectionService()
         }
 
         protected override void AddReplacements(
-            SemanticModel semanticModel,
+            SemanticModel? semanticModel,
             SyntaxNode root,
             ImmutableArray<TextSpan> spans,
             Workspace workspace,

src/Workspaces/Core/Portable/CaseCorrection/AbstractCaseCorrectionService.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;
 using System.Collections.Concurrent;
-using System.Collections.Generic;
 using System.Collections.Immutable;
 using System.Linq;
 using System.Threading;
@@ -15,7 +17,7 @@ namespace Microsoft.CodeAnalysis.CaseCorrection
 {
     internal abstract partial class AbstractCaseCorrectionService : ICaseCorrectionService
     {
-        protected abstract void AddReplacements(SemanticModel semanticModel, SyntaxNode root, ImmutableArray<TextSpan> spans, Workspace workspace, ConcurrentDictionary<SyntaxToken, SyntaxToken> replacements, CancellationToken cancellationToken);
+        protected abstract void AddReplacements(SemanticModel? semanticModel, SyntaxNode root, ImmutableArray<TextSpan> spans, Workspace workspace, ConcurrentDictionary<SyntaxToken, SyntaxToken> replacements, CancellationToken cancellationToken);
 
         public async Task<Document> CaseCorrectAsync(Document document, ImmutableArray<TextSpan> spans, CancellationToken cancellationToken)
         {
@@ -25,6 +27,11 @@ public async Task<Document> CaseCorrectAsync(Document document, ImmutableArray<T
             }
 
             var root = await document.GetSyntaxRootAsync(cancellationToken).ConfigureAwait(false);
+            if (root is null)
+            {
+                throw new NotSupportedException(WorkspacesResources.Document_does_not_support_syntax_trees);
+            }
+
             var semanticModel = await document.GetSemanticModelForSpanAsync(spans.Collapse(), cancellationToken).ConfigureAwait(false);
 
             var newRoot = CaseCorrect(semanticModel, root, spans, document.Project.Solution.Workspace, cancellationToken);
@@ -33,10 +40,10 @@ public async Task<Document> CaseCorrectAsync(Document document, ImmutableArray<T
 
         public SyntaxNode CaseCorrect(SyntaxNode root, ImmutableArray<TextSpan> spans, Workspace workspace, CancellationToken cancellationToken)
         {
-            return CaseCorrect(null, root, spans, workspace, cancellationToken);
+            return CaseCorrect(semanticModel: null, root, spans, workspace, cancellationToken);
         }
 
-        private SyntaxNode CaseCorrect(SemanticModel semanticModel, SyntaxNode root, ImmutableArray<TextSpan> spans, Workspace workspace, CancellationToken cancellationToken)
+        private SyntaxNode CaseCorrect(SemanticModel? semanticModel, SyntaxNode root, ImmutableArray<TextSpan> spans, Workspace workspace, CancellationToken cancellationToken)
         {
             using (Logger.LogBlock(FunctionId.CaseCorrection_CaseCorrect, cancellationToken))
             {

src/Workspaces/Core/Portable/CaseCorrection/CaseCorrector.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;
 using System.Collections.Immutable;
 using System.Linq;
 using System.Threading;
 using System.Threading.Tasks;
-using Microsoft.CodeAnalysis.Shared.Extensions;
 using Microsoft.CodeAnalysis.Text;
 
 namespace Microsoft.CodeAnalysis.CaseCorrection
@@ -22,6 +24,11 @@ internal static class CaseCorrector
         public static async Task<Document> CaseCorrectAsync(Document document, CancellationToken cancellationToken = default)
         {
             var root = await document.GetSyntaxRootAsync(cancellationToken).ConfigureAwait(false);
+            if (root is null)
+            {
+                throw new NotSupportedException(WorkspacesResources.Document_does_not_support_syntax_trees);
+            }
+
             return await CaseCorrectAsync(document, root.FullSpan, cancellationToken).ConfigureAwait(false);
         }
 
@@ -32,6 +39,11 @@ public static async Task<Document> CaseCorrectAsync(Document document, Cancellat
         public static async Task<Document> CaseCorrectAsync(Document document, SyntaxAnnotation annotation, CancellationToken cancellationToken = default)
         {
             var root = await document.GetSyntaxRootAsync(cancellationToken).ConfigureAwait(false);
+            if (root is null)
+            {
+                throw new NotSupportedException(WorkspacesResources.Document_does_not_support_syntax_trees);
+            }
+
             return await CaseCorrectAsync(document, root.GetAnnotatedNodesAndTokens(annotation).Select(n => n.Span).ToImmutableArray(), cancellationToken).ConfigureAwait(false);
         }
 
@@ -48,12 +60,12 @@ public static async Task<Document> CaseCorrectAsync(Document document, TextSpan
         /// Case corrects all names found in the provided spans.
         /// </summary>
         public static Task<Document> CaseCorrectAsync(Document document, ImmutableArray<TextSpan> spans, CancellationToken cancellationToken = default)
-            => document.GetLanguageService<ICaseCorrectionService>().CaseCorrectAsync(document, spans, cancellationToken);
+            => document.Project.LanguageServices.GetRequiredService<ICaseCorrectionService>().CaseCorrectAsync(document, spans, cancellationToken);
 
         /// <summary>
         /// Case correct only things that don't require semantic information
         /// </summary>
         internal static SyntaxNode CaseCorrect(SyntaxNode root, ImmutableArray<TextSpan> spans, Workspace workspace, CancellationToken cancellationToken = default)
-            => workspace.Services.GetLanguageServices(root.Language).GetService<ICaseCorrectionService>().CaseCorrect(root, spans, workspace, cancellationToken);
+            => workspace.Services.GetLanguageServices(root.Language).GetRequiredService<ICaseCorrectionService>().CaseCorrect(root, spans, workspace, cancellationToken);
     }
 }

src/Workspaces/Core/Portable/WorkspacesResources.Designer.cs

@@ -691,6 +691,15 @@ internal class WorkspacesResources {
             }
         }
         
+        /// <summary>
+        ///   Looks up a localized string similar to Document does not support syntax trees.
+        /// </summary>
+        internal static string Document_does_not_support_syntax_trees {
+            get {
+                return ResourceManager.GetString("Document_does_not_support_syntax_trees", resourceCulture);
+            }
+        }
+        
         /// <summary>
         ///   Looks up a localized string similar to Documentation comment id must start with E, F, M, N, P or T.
         /// </summary>

src/Workspaces/Core/Portable/WorkspacesResources.resx

@@ -1476,4 +1476,7 @@ Zero-width positive lookbehind assertions are typically used at the beginning of
   <data name="Warning_adding_imports_will_bring_an_extension_method_into_scope_with_the_same_name_as_member_access" xml:space="preserve">
     <value>Adding imports will bring an extension method into scope with the same name as '{0}'</value>
   </data>
+  <data name="Document_does_not_support_syntax_trees" xml:space="preserve">
+    <value>Document does not support syntax trees</value>
+  </data>
 </root>
\ No newline at end of file

src/Workspaces/Core/Portable/xlf/WorkspacesResources.cs.xlf

@@ -37,6 +37,11 @@
         <target state="translated">DateTimeKind musí být Utc</target>
         <note />
       </trans-unit>
+      <trans-unit id="Document_does_not_support_syntax_trees">
+        <source>Document does not support syntax trees</source>
+        <target state="new">Document does not support syntax trees</target>
+        <note />
+      </trans-unit>
       <trans-unit id="Expression_level_preferences">
         <source>Expression-level preferences</source>
         <target state="translated">Předvolby na úrovni výrazů</target>

src/Workspaces/Core/Portable/xlf/WorkspacesResources.de.xlf

@@ -37,6 +37,11 @@
         <target state="translated">"DateTimeKind" muss UTC sein.</target>
         <note />
       </trans-unit>
+      <trans-unit id="Document_does_not_support_syntax_trees">
+        <source>Document does not support syntax trees</source>
+        <target state="new">Document does not support syntax trees</target>
+        <note />
+      </trans-unit>
       <trans-unit id="Expression_level_preferences">
         <source>Expression-level preferences</source>
         <target state="translated">Einstellungen für Ausdrucksebene</target>

src/Workspaces/Core/Portable/xlf/WorkspacesResources.es.xlf

@@ -37,6 +37,11 @@
         <target state="translated">DateTimeKind debe ser Utc</target>
         <note />
       </trans-unit>
+      <trans-unit id="Document_does_not_support_syntax_trees">
+        <source>Document does not support syntax trees</source>
+        <target state="new">Document does not support syntax trees</target>
+        <note />
+      </trans-unit>
       <trans-unit id="Expression_level_preferences">
         <source>Expression-level preferences</source>
         <target state="translated">Preferencias de nivel de expresión</target>

src/Workspaces/Core/Portable/xlf/WorkspacesResources.fr.xlf

@@ -37,6 +37,11 @@
         <target state="translated">DateTimeKind doit être UTC</target>
         <note />
       </trans-unit>
+      <trans-unit id="Document_does_not_support_syntax_trees">
+        <source>Document does not support syntax trees</source>
+        <target state="new">Document does not support syntax trees</target>
+        <note />
+      </trans-unit>
       <trans-unit id="Expression_level_preferences">
         <source>Expression-level preferences</source>
         <target state="translated">Préférences de niveau expression</target>

src/Workspaces/Core/Portable/xlf/WorkspacesResources.it.xlf

@@ -37,6 +37,11 @@
         <target state="translated">Il valore di DateTimeKind deve essere Utc</target>
         <note />
       </trans-unit>
+      <trans-unit id="Document_does_not_support_syntax_trees">
+        <source>Document does not support syntax trees</source>
+        <target state="new">Document does not support syntax trees</target>
+        <note />
+      </trans-unit>
       <trans-unit id="Expression_level_preferences">
         <source>Expression-level preferences</source>
         <target state="translated">Preferenze a livello di espressione</target>

src/Workspaces/Core/Portable/xlf/WorkspacesResources.ja.xlf

@@ -37,6 +37,11 @@
         <target state="translated">DateTimeKind は Utc にする必要があります</target>
         <note />
       </trans-unit>
+      <trans-unit id="Document_does_not_support_syntax_trees">
+        <source>Document does not support syntax trees</source>
+        <target state="new">Document does not support syntax trees</target>
+        <note />
+      </trans-unit>
       <trans-unit id="Expression_level_preferences">
         <source>Expression-level preferences</source>
         <target state="translated">式レベルの設定</target>

src/Workspaces/Core/Portable/xlf/WorkspacesResources.ko.xlf

@@ -37,6 +37,11 @@
         <target state="translated">DateTimeKind는 UTC여야 합니다.</target>
         <note />
       </trans-unit>
+      <trans-unit id="Document_does_not_support_syntax_trees">
+        <source>Document does not support syntax trees</source>
+        <target state="new">Document does not support syntax trees</target>
+        <note />
+      </trans-unit>
       <trans-unit id="Expression_level_preferences">
         <source>Expression-level preferences</source>
         <target state="translated">식 수준 기본 설정</target>

src/Workspaces/Core/Portable/xlf/WorkspacesResources.pl.xlf

@@ -37,6 +37,11 @@
         <target state="translated">Element DateTimeKind musi mieć wartość Utc</target>
         <note />
       </trans-unit>
+      <trans-unit id="Document_does_not_support_syntax_trees">
+        <source>Document does not support syntax trees</source>
+        <target state="new">Document does not support syntax trees</target>
+        <note />
+      </trans-unit>
       <trans-unit id="Expression_level_preferences">
         <source>Expression-level preferences</source>
         <target state="translated">Preferencje na poziomie wyrażeń</target>

src/Workspaces/Core/Portable/xlf/WorkspacesResources.pt-BR.xlf

@@ -37,6 +37,11 @@
         <target state="translated">DateTimeKind deve ser Utc</target>
         <note />
       </trans-unit>
+      <trans-unit id="Document_does_not_support_syntax_trees">
+        <source>Document does not support syntax trees</source>
+        <target state="new">Document does not support syntax trees</target>
+        <note />
+      </trans-unit>
       <trans-unit id="Expression_level_preferences">
         <source>Expression-level preferences</source>
         <target state="translated">Preferências de nível de expressão</target>

src/Workspaces/Core/Portable/xlf/WorkspacesResources.ru.xlf

@@ -37,6 +37,11 @@
         <target state="translated">Параметр DateTimeKind должен содержать время и дату в формате UTC</target>
         <note />
       </trans-unit>
+      <trans-unit id="Document_does_not_support_syntax_trees">
+        <source>Document does not support syntax trees</source>
+        <target state="new">Document does not support syntax trees</target>
+        <note />
+      </trans-unit>
       <trans-unit id="Expression_level_preferences">
         <source>Expression-level preferences</source>
         <target state="translated">Выражения уровень предпочтения</target>

src/Workspaces/Core/Portable/xlf/WorkspacesResources.tr.xlf

@@ -37,6 +37,11 @@
         <target state="translated">DateTimeKind Utc olmalıdır</target>
         <note />
       </trans-unit>
+      <trans-unit id="Document_does_not_support_syntax_trees">
+        <source>Document does not support syntax trees</source>
+        <target state="new">Document does not support syntax trees</target>
+        <note />
+      </trans-unit>
       <trans-unit id="Expression_level_preferences">
         <source>Expression-level preferences</source>
         <target state="translated">İfade düzey tercihleri</target>

src/Workspaces/Core/Portable/xlf/WorkspacesResources.zh-Hans.xlf

@@ -37,6 +37,11 @@
         <target state="translated">DateTimeKind 必须是 Utc</target>
         <note />
       </trans-unit>
+      <trans-unit id="Document_does_not_support_syntax_trees">
+        <source>Document does not support syntax trees</source>
+        <target state="new">Document does not support syntax trees</target>
+        <note />
+      </trans-unit>
       <trans-unit id="Expression_level_preferences">
         <source>Expression-level preferences</source>
         <target state="translated">表达式级首选项</target>

src/Workspaces/Core/Portable/xlf/WorkspacesResources.zh-Hant.xlf

@@ -37,6 +37,11 @@
         <target state="translated">DateTimeKind 必須是 Utc</target>
         <note />
       </trans-unit>
+      <trans-unit id="Document_does_not_support_syntax_trees">
+        <source>Document does not support syntax trees</source>
+        <target state="new">Document does not support syntax trees</target>
+        <note />
+      </trans-unit>
       <trans-unit id="Expression_level_preferences">
         <source>Expression-level preferences</source>
         <target state="translated">運算式層級喜好設定</target>