Simplify remove-cast implementation.

src/EditorFeatures/CSharpTest/Diagnostics/RemoveUnnecessaryCast/RemoveUnnecessaryCastTests.cs

@@ -59,7 +59,7 @@ static void Main()
     {
         int x = 2;
         int i = 1;
-        Goo((x < i), x > (2 + 3));
+        Goo(x < (i), x > (2 + 3));
     }
  
     static void Goo(bool a, bool b) { }
@@ -3550,7 +3550,7 @@ class C
 {
     void Goo(Task<Action> x)
     {
-        x.Result();
+        (x.Result)();
     }
 }
 ");

src/EditorFeatures/Test2/Simplification/CastSimplificationTests.vb

@@ -367,7 +367,7 @@ class C
 {
     void M()
     {
-        System.Action a = (() => { });
+        System.Action a = () => { };
     }
 }
 </code>
@@ -401,13 +401,12 @@ class C
     void M()
     {
         System.Action a = null;
-        a = (() => { });
+        a = () => { };
     }
 }
 </code>
 
             Await TestAsync(input, expected)
-
         End Function
 
         <Fact, Trait(Traits.Feature, Traits.Features.Simplification)>
@@ -435,7 +434,7 @@ class C
 {
     void M()
     {
-        Goo((() => "Goo"));
+        Goo(() => "Goo");
     }
 
     void Goo&lt;T&gt;(System.Func&lt;T&gt; f) { }
@@ -471,7 +470,7 @@ class C
 {
     void M()
     {
-        Goo(f: (() => "Goo"));
+        Goo(f: () => "Goo");
     }
 
     void Goo&lt;T&gt;(System.Func&lt;T&gt; f) { }
@@ -3207,7 +3206,7 @@ static class Program
 {
     static void Main()
     {
-        new Action<string>((y => Goo(1)))(null);
+        new Action<string>(y => Goo(1))(null);
     }
  
     static void Goo(this object x) { Console.WriteLine(1); }
@@ -3254,7 +3253,7 @@ static class Program
 {
     static void Main()
     {
-        new Action<string>(((y) => { string x = y; x.Goo(); }))(null);
+        new Action<string>((y) => { string x = y; x.Goo(); })(null);
     }
  
     static void Goo(this object x) { Console.WriteLine(1); }
@@ -3397,7 +3396,7 @@ static class Program
 {
     static void Main()
     {
-        new Action<string, object>(((y, z) => { object x = y; z.Goo(); }))(null, null);
+        new Action<string, object>((y, z) => { object x = y; z.Goo(); })(null, null);
     }
 
     static void Goo(this object x) { Console.WriteLine(1); }
@@ -3533,7 +3532,7 @@ class Program
 {
     static void Main(string[] args)
     {
-        Func<Exception> f = (() => new ArgumentException());
+        Func<Exception> f = () => new ArgumentException();
     }
 }
 ]]>

src/Features/CSharp/Portable/CSharpFeaturesResources.Designer.cs

@@ -215,15 +215,6 @@ internal class CSharpFeaturesResources {
             }
         }
         
-        /// <summary>
-        ///   Looks up a localized string similar to Cast is redundant.
-        /// </summary>
-        internal static string Cast_is_redundant {
-            get {
-                return ResourceManager.GetString("Cast_is_redundant", resourceCulture);
-            }
-        }
-        
         /// <summary>
         ///   Looks up a localized string similar to catch clause.
         /// </summary>
@@ -827,15 +818,6 @@ internal class CSharpFeaturesResources {
             }
         }
         
-        /// <summary>
-        ///   Looks up a localized string similar to Remove Unnecessary Cast.
-        /// </summary>
-        internal static string Remove_Unnecessary_Cast {
-            get {
-                return ResourceManager.GetString("Remove_Unnecessary_Cast", resourceCulture);
-            }
-        }
-        
         /// <summary>
         ///   Looks up a localized string similar to Remove Unnecessary Usings.
         /// </summary>

src/Features/CSharp/Portable/CSharpFeaturesResources.resx

@@ -159,12 +159,6 @@
   <data name="Autoselect_disabled_due_to_potential_range_variable_declaration" xml:space="preserve">
     <value>Autoselect disabled due to potential range variable declaration.</value>
   </data>
-  <data name="Remove_Unnecessary_Cast" xml:space="preserve">
-    <value>Remove Unnecessary Cast</value>
-  </data>
-  <data name="Cast_is_redundant" xml:space="preserve">
-    <value>Cast is redundant</value>
-  </data>
   <data name="Simplify_name_0" xml:space="preserve">
     <value>Simplify name '{0}'</value>
   </data>

src/Features/CSharp/Portable/CodeFixes/RemoveUnnecessaryCast/RemoveUnnecessaryCastCodeFixProvider.RemoveUnnecessaryCastFixAllProvider.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.Threading;
-using System.Threading.Tasks;
-using Microsoft.CodeAnalysis.CodeFixes;
-using Microsoft.CodeAnalysis.CSharp.Syntax;
-using Microsoft.CodeAnalysis.Options;
-
-namespace Microsoft.CodeAnalysis.CSharp.CodeFixes.RemoveUnnecessaryCast
-{
-    internal partial class RemoveUnnecessaryCastCodeFixProvider : CodeFixProvider
-    {
-        private class RemoveUnnecessaryCastFixAllProvider : BatchSimplificationFixAllProvider
-        {
-            internal static new readonly RemoveUnnecessaryCastFixAllProvider Instance = new RemoveUnnecessaryCastFixAllProvider();
-
-            protected override SyntaxNode GetNodeToSimplify(SyntaxNode root, SemanticModel model, Diagnostic diagnostic, DocumentOptionSet options, out string codeActionId, CancellationToken cancellationToken)
-            {
-                codeActionId = null;
-                return GetCastNode(root, model, diagnostic.Location.SourceSpan, cancellationToken);
-            }
-
-            protected override bool NeedsParentFixup => true;
-
-            protected override async Task<Document> AddSimplifyAnnotationsAsync(Document document, SyntaxNode nodeToSimplify, CancellationToken cancellationToken)
-            {
-                var cast = nodeToSimplify as CastExpressionSyntax;
-                if (cast == null)
-                {
-                    return null;
-                }
-
-                return await RemoveUnnecessaryCastAsync(document, cast, cancellationToken).ConfigureAwait(false);
-            }
-        }
-    }
-}

src/Features/CSharp/Portable/CodeFixes/RemoveUnnecessaryCast/RemoveUnnecessaryCastCodeFixProvider.cs

@@ -11,6 +11,7 @@
 using Microsoft.CodeAnalysis.CSharp.Extensions;
 using Microsoft.CodeAnalysis.CSharp.Syntax;
 using Microsoft.CodeAnalysis.Diagnostics;
+using Microsoft.CodeAnalysis.Editing;
 using Microsoft.CodeAnalysis.Formatting;
 using Microsoft.CodeAnalysis.Shared.Extensions;
 using Microsoft.CodeAnalysis.Simplification;
@@ -21,89 +22,68 @@ namespace Microsoft.CodeAnalysis.CSharp.CodeFixes.RemoveUnnecessaryCast
 {
     [ExportCodeFixProvider(LanguageNames.CSharp, Name = PredefinedCodeFixProviderNames.RemoveUnnecessaryCast), Shared]
     [ExtensionOrder(After = PredefinedCodeFixProviderNames.ImplementInterface)]
-    internal partial class RemoveUnnecessaryCastCodeFixProvider : CodeFixProvider
+    internal partial class RemoveUnnecessaryCastCodeFixProvider : SyntaxEditorBasedCodeFixProvider
     {
-        public sealed override ImmutableArray<string> FixableDiagnosticIds
-        {
-            get { return ImmutableArray.Create(IDEDiagnosticIds.RemoveUnnecessaryCastDiagnosticId); }
-        }
-
-        public sealed override FixAllProvider GetFixAllProvider()
-        {
-            return RemoveUnnecessaryCastFixAllProvider.Instance;
-        }
-
-        private static CastExpressionSyntax GetCastNode(SyntaxNode root, SemanticModel model, TextSpan span, CancellationToken cancellationToken)
-        {
-            var token = root.FindToken(span.Start);
-            if (!token.Span.IntersectsWith(span))
-            {
-                return null;
-            }
-
-            return token.GetAncestors<CastExpressionSyntax>()
-                .FirstOrDefault(c => c.Span.IntersectsWith(span) && c.IsUnnecessaryCast(model, cancellationToken));
-        }
+        public sealed override ImmutableArray<string> FixableDiagnosticIds { get; } =
+            ImmutableArray.Create(IDEDiagnosticIds.RemoveUnnecessaryCastDiagnosticId);
 
         public sealed override Task RegisterCodeFixesAsync(CodeFixContext context)
         {
-            context.RegisterCodeFix(
-                new MyCodeAction(
-                    CSharpFeaturesResources.Remove_Unnecessary_Cast,
-                    c => RemoveUnnecessaryCastAsync(context.Document, context.Span, c)),
+            context.RegisterCodeFix(new MyCodeAction(
+                FeaturesResources.Remove_Unnecessary_Cast,
+                c => FixAsync(context.Document, context.Diagnostics.First(), c)),
                 context.Diagnostics);
             return SpecializedTasks.EmptyTask;
         }
 
-        private static async Task<Document> RemoveUnnecessaryCastAsync(
-            Document document, TextSpan span, CancellationToken cancellationToken)
+        protected override async Task FixAllAsync(
+            Document document, ImmutableArray<Diagnostic> diagnostics,
+            SyntaxEditor editor, CancellationToken cancellationToken)
         {
-            var root = await document.GetSyntaxRootAsync(cancellationToken).ConfigureAwait(false);
-            var model = await document.GetSemanticModelAsync(cancellationToken).ConfigureAwait(false);
-            var cast = GetCastNode(root, model, span, cancellationToken);
-            return await RemoveUnnecessaryCastAsync(document, cast, cancellationToken).ConfigureAwait(false);
+            var castNodes = diagnostics.SelectAsArray(
+                d => (CastExpressionSyntax)d.AdditionalLocations[0].FindNode(getInnermostNodeForTie: true, cancellationToken));
+
+            await editor.ApplyExpressionLevelSemanticEditsAsync(
+                document, castNodes,
+                (semanticModel, castExpression) => castExpression.IsUnnecessaryCast(semanticModel, cancellationToken),
+                (_, currentRoot, castExpression) =>
+                {
+                    var (oldParent, newParent) = Update(castExpression);
+                    return currentRoot.ReplaceNode(oldParent, newParent);
+                },
+                cancellationToken).ConfigureAwait(false);
         }
 
-        private static async Task<Document> RemoveUnnecessaryCastAsync(
-            Document document, CastExpressionSyntax cast, CancellationToken cancellationToken)
+        private (ExpressionSyntax, ExpressionSyntax) Update(CastExpressionSyntax castExpression)
         {
-            var root = await document.GetSyntaxRootAsync(cancellationToken).ConfigureAwait(false);
+            var oldParent = castExpression.WalkUpParentheses();
+            var newParent = Recurse(oldParent);
 
-            var annotatedCast = cast.WithAdditionalAnnotations(Simplifier.Annotation);
+            return (oldParent, newParent);
+        }
 
-            if (annotatedCast.Expression is ParenthesizedExpressionSyntax)
+        private ExpressionSyntax Recurse(ExpressionSyntax old)
+        {
+            if (old is ParenthesizedExpressionSyntax parenthesizedExpression)
             {
-                annotatedCast = annotatedCast.WithExpression(
-                    annotatedCast.Expression.WithAdditionalAnnotations(Simplifier.Annotation));
+                // It's common in C# to have to write  ((Goo)expr).Etc(). we don't just want to
+                // remove the cast and produce (expr).Etc().  So we mark all parent parenthesized
+                // expressions as worthy of simplification.  The simplifier will remove these
+                // if possible, or leave them alone if not.
+                return parenthesizedExpression.ReplaceNode(parenthesizedExpression.Expression, Recurse(parenthesizedExpression.Expression))
+                                              .WithAdditionalAnnotations(Simplifier.Annotation);
             }
-            else
+            else if (old is CastExpressionSyntax castExpression)
             {
-                annotatedCast = annotatedCast.WithExpression(
-                    annotatedCast.Expression.Parenthesize());
+                // parenthesize the uncasted value to help ensure any proper parsing. The excess
+                // parens will be removed if unnecessary. 
+                return castExpression.Uncast().WithAdditionalAnnotations(Formatter.Annotation)
+                                     .Parenthesize();
             }
-
-            ExpressionSyntax oldNode = cast;
-            ExpressionSyntax newNode = annotatedCast;
-
-            // Ensure that we simplify any parenting parenthesized expressions not just on the syntax tree level but also on Token based
-            // Case 1:
-            //  In the syntax, (((Task<Action>)x).Result)() 
-            //                 oldNode = (Task<Action>)x
-            //                 newNode = (Task<Action>)(x)
-            //                 Final newNode will be (((Task<Action>)(x)).Result)
-            while (oldNode.Parent.IsKind(SyntaxKind.ParenthesizedExpression) || oldNode.GetFirstToken().GetPreviousToken().Parent.IsKind(SyntaxKind.ParenthesizedExpression))
+            else
             {
-                var parenthesizedExpression = (ParenthesizedExpressionSyntax)oldNode.GetFirstToken().GetPreviousToken().Parent;
-                newNode = parenthesizedExpression.ReplaceNode(oldNode, newNode)
-                    .WithAdditionalAnnotations(Simplifier.Annotation);
-                oldNode = parenthesizedExpression;
+                throw ExceptionUtilities.UnexpectedValue(old);
             }
-
-            newNode = newNode.WithAdditionalAnnotations(Formatter.Annotation);
-
-            var newRoot = root.ReplaceNode(oldNode, newNode);
-
-            return document.WithSyntaxRoot(newRoot);
         }
 
         private class MyCodeAction : CodeAction.DocumentChangeAction

src/Features/CSharp/Portable/Diagnostics/Analyzers/CSharpRemoveUnnecessaryCastDiagnosticAnalyzer.cs

@@ -11,22 +11,17 @@
 namespace Microsoft.CodeAnalysis.CSharp.Diagnostics.RemoveUnnecessaryCast
 {
     [DiagnosticAnalyzer(LanguageNames.CSharp)]
-    internal sealed class CSharpRemoveUnnecessaryCastDiagnosticAnalyzer : RemoveUnnecessaryCastDiagnosticAnalyzerBase<SyntaxKind>
+    internal sealed class CSharpRemoveUnnecessaryCastDiagnosticAnalyzer 
+        : RemoveUnnecessaryCastDiagnosticAnalyzerBase<SyntaxKind, CastExpressionSyntax>
     {
         private static readonly ImmutableArray<SyntaxKind> s_kindsOfInterest = ImmutableArray.Create(SyntaxKind.CastExpression);
 
-        public override ImmutableArray<SyntaxKind> SyntaxKindsOfInterest => s_kindsOfInterest;
+        protected override ImmutableArray<SyntaxKind> SyntaxKindsOfInterest => s_kindsOfInterest;
 
-        protected override bool IsUnnecessaryCast(SemanticModel model, SyntaxNode node, CancellationToken cancellationToken)
-        {
-            var cast = (CastExpressionSyntax)node;
-            return cast.IsUnnecessaryCast(model, cancellationToken);
-        }
+        protected override bool IsUnnecessaryCast(SemanticModel model, CastExpressionSyntax cast, CancellationToken cancellationToken)
+            => cast.IsUnnecessaryCast(model, cancellationToken);
 
-        protected override TextSpan GetDiagnosticSpan(SyntaxNode node)
-        {
-            var cast = (CastExpressionSyntax)node;
-            return TextSpan.FromBounds(cast.OpenParenToken.SpanStart, cast.CloseParenToken.Span.End);
-        }
+        protected override TextSpan GetFadeSpan(CastExpressionSyntax node)
+            => TextSpan.FromBounds(node.OpenParenToken.SpanStart, node.CloseParenToken.Span.End);
     }
 }

src/Features/CSharp/Portable/xlf/CSharpFeaturesResources.cs.xlf

@@ -67,16 +67,6 @@
         <target state="translated">Automatický výběr je zakázaný kvůli možné deklaraci proměnné rozsahu.</target>
         <note />
       </trans-unit>
-      <trans-unit id="Remove_Unnecessary_Cast">
-        <source>Remove Unnecessary Cast</source>
-        <target state="translated">Odebrat nepotřebné přetypování</target>
-        <note />
-      </trans-unit>
-      <trans-unit id="Cast_is_redundant">
-        <source>Cast is redundant</source>
-        <target state="translated">Přetypování je redundantní.</target>
-        <note />
-      </trans-unit>
       <trans-unit id="Simplify_name_0">
         <source>Simplify name '{0}'</source>
         <target state="translated">Zjednodušit název {0}</target>

src/Features/CSharp/Portable/xlf/CSharpFeaturesResources.de.xlf

@@ -67,16 +67,6 @@
         <target state="translated">Automatische Auswahl aufgrund einer potzenziellen Bereichvariablendeklaration deaktiviert.</target>
         <note />
       </trans-unit>
-      <trans-unit id="Remove_Unnecessary_Cast">
-        <source>Remove Unnecessary Cast</source>
-        <target state="translated">Nicht erforderliche Umwandlung entfernen</target>
-        <note />
-      </trans-unit>
-      <trans-unit id="Cast_is_redundant">
-        <source>Cast is redundant</source>
-        <target state="translated">Cast ist redundant</target>
-        <note />
-      </trans-unit>
       <trans-unit id="Simplify_name_0">
         <source>Simplify name '{0}'</source>
         <target state="translated">Name '{0}' vereinfachen</target>

src/Features/CSharp/Portable/xlf/CSharpFeaturesResources.es.xlf

@@ -67,16 +67,6 @@
         <target state="translated">La selección automática se ha deshabilitado debido posiblemente a una declaración de variable de rango.</target>
         <note />
       </trans-unit>
-      <trans-unit id="Remove_Unnecessary_Cast">
-        <source>Remove Unnecessary Cast</source>
-        <target state="translated">Quitar conversión innecesaria</target>
-        <note />
-      </trans-unit>
-      <trans-unit id="Cast_is_redundant">
-        <source>Cast is redundant</source>
-        <target state="translated">Cast es redundante</target>
-        <note />
-      </trans-unit>
       <trans-unit id="Simplify_name_0">
         <source>Simplify name '{0}'</source>
         <target state="translated">Simplificar nombre '{0}'</target>

src/Features/CSharp/Portable/xlf/CSharpFeaturesResources.fr.xlf

@@ -67,16 +67,6 @@
         <target state="translated">Sélection automatique désactivée en raison d'une déclaration de variable de plage éventuelle.</target>
         <note />
       </trans-unit>
-      <trans-unit id="Remove_Unnecessary_Cast">
-        <source>Remove Unnecessary Cast</source>
-        <target state="translated">Supprimer le cast inutile</target>
-        <note />
-      </trans-unit>
-      <trans-unit id="Cast_is_redundant">
-        <source>Cast is redundant</source>
-        <target state="translated">Cast redondant</target>
-        <note />
-      </trans-unit>
       <trans-unit id="Simplify_name_0">
         <source>Simplify name '{0}'</source>
         <target state="translated">Simplifier le nom '{0}'</target>

src/Features/CSharp/Portable/xlf/CSharpFeaturesResources.it.xlf

@@ -67,16 +67,6 @@
         <target state="translated">La selezione automatica è disabilitata a causa di una potenziale dichiarazione della variabile di intervallo.</target>
         <note />
       </trans-unit>
-      <trans-unit id="Remove_Unnecessary_Cast">
-        <source>Remove Unnecessary Cast</source>
-        <target state="translated">Rimuovi cast non necessario</target>
-        <note />
-      </trans-unit>
-      <trans-unit id="Cast_is_redundant">
-        <source>Cast is redundant</source>
-        <target state="translated">Il cast è ridondante</target>
-        <note />
-      </trans-unit>
       <trans-unit id="Simplify_name_0">
         <source>Simplify name '{0}'</source>
         <target state="translated">Semplifica il nome '{0}'</target>

src/Features/CSharp/Portable/xlf/CSharpFeaturesResources.ja.xlf

@@ -67,16 +67,6 @@
         <target state="translated">範囲変数宣言の可能性があるため、自動選択は無効になっています。</target>
         <note />
       </trans-unit>
-      <trans-unit id="Remove_Unnecessary_Cast">
-        <source>Remove Unnecessary Cast</source>
-        <target state="translated">不要なキャストの削除</target>
-        <note />
-      </trans-unit>
-      <trans-unit id="Cast_is_redundant">
-        <source>Cast is redundant</source>
-        <target state="translated">キャストが冗長です</target>
-        <note />
-      </trans-unit>
       <trans-unit id="Simplify_name_0">
         <source>Simplify name '{0}'</source>
         <target state="translated">名前 '{0}' の単純化</target>

src/Features/CSharp/Portable/xlf/CSharpFeaturesResources.ko.xlf

@@ -67,16 +67,6 @@
         <target state="translated">범위 변수가 선언될 수 있어 자동 선택을 사용하지 않도록 설정했습니다.</target>
         <note />
       </trans-unit>
-      <trans-unit id="Remove_Unnecessary_Cast">
-        <source>Remove Unnecessary Cast</source>
-        <target state="translated">불필요한 캐스트 제거</target>
-        <note />
-      </trans-unit>
-      <trans-unit id="Cast_is_redundant">
-        <source>Cast is redundant</source>
-        <target state="translated">캐스팅이 중복됩니다.</target>
-        <note />
-      </trans-unit>
       <trans-unit id="Simplify_name_0">
         <source>Simplify name '{0}'</source>
         <target state="translated">{0}' 이름 단순화</target>

src/Features/CSharp/Portable/xlf/CSharpFeaturesResources.pl.xlf

@@ -67,16 +67,6 @@
         <target state="translated">Automatyczne zaznaczanie zostało wyłączone z powodu możliwej deklaracji zmiennej zakresu.</target>
         <note />
       </trans-unit>
-      <trans-unit id="Remove_Unnecessary_Cast">
-        <source>Remove Unnecessary Cast</source>
-        <target state="translated">Usuń niepotrzebne rzutowanie</target>
-        <note />
-      </trans-unit>
-      <trans-unit id="Cast_is_redundant">
-        <source>Cast is redundant</source>
-        <target state="translated">Nadmiarowe określenie elementu Cast</target>
-        <note />
-      </trans-unit>
       <trans-unit id="Simplify_name_0">
         <source>Simplify name '{0}'</source>
         <target state="translated">Uprość nazwę „{0}”</target>

src/Features/CSharp/Portable/xlf/CSharpFeaturesResources.pt-BR.xlf

@@ -67,16 +67,6 @@
         <target state="translated">Seleção automática desabilitada devido a uma possível declaração de variável de intervalo.</target>
         <note />
       </trans-unit>
-      <trans-unit id="Remove_Unnecessary_Cast">
-        <source>Remove Unnecessary Cast</source>
-        <target state="translated">Remover Conversão Desnecessária</target>
-        <note />
-      </trans-unit>
-      <trans-unit id="Cast_is_redundant">
-        <source>Cast is redundant</source>
-        <target state="translated">A conversão é redundante</target>
-        <note />
-      </trans-unit>
       <trans-unit id="Simplify_name_0">
         <source>Simplify name '{0}'</source>
         <target state="translated">Simplificar nome '{0}'</target>

src/Features/CSharp/Portable/xlf/CSharpFeaturesResources.ru.xlf

@@ -67,16 +67,6 @@
         <target state="translated">Автовыбор отключен из-за возможного объявления переменной диапазона.</target>
         <note />
       </trans-unit>
-      <trans-unit id="Remove_Unnecessary_Cast">
-        <source>Remove Unnecessary Cast</source>
-        <target state="translated">Удалить ненужное приведение</target>
-        <note />
-      </trans-unit>
-      <trans-unit id="Cast_is_redundant">
-        <source>Cast is redundant</source>
-        <target state="translated">Приведение избыточно</target>
-        <note />
-      </trans-unit>
       <trans-unit id="Simplify_name_0">
         <source>Simplify name '{0}'</source>
         <target state="translated">Упрощение имени "{0}"</target>

src/Features/CSharp/Portable/xlf/CSharpFeaturesResources.tr.xlf

@@ -67,16 +67,6 @@
         <target state="translated">Otomatik seçim, olası aralık değişkeni bildirimi nedeniyle devre dışı bırakıldı.</target>
         <note />
       </trans-unit>
-      <trans-unit id="Remove_Unnecessary_Cast">
-        <source>Remove Unnecessary Cast</source>
-        <target state="translated">Gereksiz Atamayı Kaldır</target>
-        <note />
-      </trans-unit>
-      <trans-unit id="Cast_is_redundant">
-        <source>Cast is redundant</source>
-        <target state="translated">Atama gereksiz</target>
-        <note />
-      </trans-unit>
       <trans-unit id="Simplify_name_0">
         <source>Simplify name '{0}'</source>
         <target state="translated">{0}' adını basitleştir</target>

src/Features/CSharp/Portable/xlf/CSharpFeaturesResources.zh-Hans.xlf

@@ -67,16 +67,6 @@
         <target state="translated">由于可能出现范围变量声明，已禁用自动选择。</target>
         <note />
       </trans-unit>
-      <trans-unit id="Remove_Unnecessary_Cast">
-        <source>Remove Unnecessary Cast</source>
-        <target state="translated">删除不必要的转换</target>
-        <note />
-      </trans-unit>
-      <trans-unit id="Cast_is_redundant">
-        <source>Cast is redundant</source>
-        <target state="translated">强制转换是多余的</target>
-        <note />
-      </trans-unit>
       <trans-unit id="Simplify_name_0">
         <source>Simplify name '{0}'</source>
         <target state="translated">简化名称“{0}”</target>

src/Features/CSharp/Portable/xlf/CSharpFeaturesResources.zh-Hant.xlf

@@ -67,16 +67,6 @@
         <target state="translated">由於可能的範圍變數宣告，所以停用自動選取。</target>
         <note />
       </trans-unit>
-      <trans-unit id="Remove_Unnecessary_Cast">
-        <source>Remove Unnecessary Cast</source>
-        <target state="translated">移除不必要的 Cast</target>
-        <note />
-      </trans-unit>
-      <trans-unit id="Cast_is_redundant">
-        <source>Cast is redundant</source>
-        <target state="translated">Cast 是多餘的</target>
-        <note />
-      </trans-unit>
       <trans-unit id="Simplify_name_0">
         <source>Simplify name '{0}'</source>
         <target state="translated">簡化名稱 '{0}'</target>

src/Features/Core/Portable/Diagnostics/Analyzers/RemoveUnnecessaryCastDiagnosticAnalyzerBase.cs

@@ -3,76 +3,70 @@
 using System.Collections.Immutable;
 using System.Linq;
 using System.Threading;
+using Microsoft.CodeAnalysis.CodeStyle;
 using Microsoft.CodeAnalysis.Shared.Extensions;
 using Microsoft.CodeAnalysis.Text;
 
 namespace Microsoft.CodeAnalysis.Diagnostics.RemoveUnnecessaryCast
 {
-    internal abstract class RemoveUnnecessaryCastDiagnosticAnalyzerBase<TLanguageKindEnum> : DiagnosticAnalyzer, IBuiltInAnalyzer where TLanguageKindEnum : struct
+    internal abstract class RemoveUnnecessaryCastDiagnosticAnalyzerBase<
+        TLanguageKindEnum,
+        TCastExpression> : AbstractCodeStyleDiagnosticAnalyzer
+        where TLanguageKindEnum : struct
+        where TCastExpression : SyntaxNode
     {
-        private static readonly LocalizableString s_localizableTitle = new LocalizableResourceString(nameof(FeaturesResources.Remove_Unnecessary_Cast), FeaturesResources.ResourceManager, typeof(FeaturesResources));
-        private static readonly LocalizableString s_localizableMessage = new LocalizableResourceString(nameof(WorkspacesResources.Cast_is_redundant), WorkspacesResources.ResourceManager, typeof(WorkspacesResources));
+        protected RemoveUnnecessaryCastDiagnosticAnalyzerBase()
+            : base(IDEDiagnosticIds.RemoveUnnecessaryCastDiagnosticId,
+                   new LocalizableResourceString(nameof(FeaturesResources.Remove_Unnecessary_Cast), FeaturesResources.ResourceManager, typeof(FeaturesResources)),
+                   new LocalizableResourceString(nameof(WorkspacesResources.Cast_is_redundant), WorkspacesResources.ResourceManager, typeof(WorkspacesResources)))
+        {
+        }
+
+        protected abstract ImmutableArray<TLanguageKindEnum> SyntaxKindsOfInterest { get; }
+        protected abstract TextSpan GetFadeSpan(TCastExpression node);
+        protected abstract bool IsUnnecessaryCast(SemanticModel model, TCastExpression node, CancellationToken cancellationToken);
 
-        private static readonly DiagnosticDescriptor s_descriptor = new DiagnosticDescriptor(IDEDiagnosticIds.RemoveUnnecessaryCastDiagnosticId,
-            s_localizableTitle,
-            s_localizableMessage,
-            DiagnosticCategory.Style,
-            DiagnosticSeverity.Hidden,
-            isEnabledByDefault: true,
-            customTags: DiagnosticCustomTags.Unnecessary);
+        public override bool OpenFileOnly(Workspace workspace)
+            => false;
 
-        #region Interface methods
+        public override DiagnosticAnalyzerCategory GetAnalyzerCategory()
+            => DiagnosticAnalyzerCategory.SemanticSpanAnalysis;
 
-        public override ImmutableArray<DiagnosticDescriptor> SupportedDiagnostics => ImmutableArray.Create(s_descriptor);
-        public bool OpenFileOnly(Workspace workspace) => false;
+        protected override void InitializeWorker(AnalysisContext context)
+            => context.RegisterSyntaxNodeAction(AnalyzeSyntax, this.SyntaxKindsOfInterest);
 
-        public sealed override void Initialize(AnalysisContext context)
+        private void AnalyzeSyntax(SyntaxNodeAnalysisContext context)
         {
-            context.ConfigureGeneratedCodeAnalysis(GeneratedCodeAnalysisFlags.None);
-            context.EnableConcurrentExecution();
+            var diagnostic = TryRemoveCastExpression(
+                context.SemanticModel,
+                (TCastExpression)context.Node,
+                context.CancellationToken);
 
-            context.RegisterSyntaxNodeAction(
-                nodeContext =>
-                    {
-                        if (TryRemoveCastExpression(nodeContext.SemanticModel, nodeContext.Node, out var diagnostic, nodeContext.CancellationToken))
-                        {
-                            nodeContext.ReportDiagnostic(diagnostic);
-                        }
-                    },
-                this.SyntaxKindsOfInterest.ToArray());
+            if (diagnostic != null)
+            {
+                context.ReportDiagnostic(diagnostic);
+            }
         }
 
-        public abstract ImmutableArray<TLanguageKindEnum> SyntaxKindsOfInterest { get; }
-
-        #endregion
-
-        protected abstract bool IsUnnecessaryCast(SemanticModel model, SyntaxNode node, CancellationToken cancellationToken);
-        protected abstract TextSpan GetDiagnosticSpan(SyntaxNode node);
-
-        private bool TryRemoveCastExpression(
-            SemanticModel model, SyntaxNode node, out Diagnostic diagnostic, CancellationToken cancellationToken)
+        private Diagnostic TryRemoveCastExpression(SemanticModel model, TCastExpression node, CancellationToken cancellationToken)
         {
             cancellationToken.ThrowIfCancellationRequested();
 
-            diagnostic = default;
-
             if (!IsUnnecessaryCast(model, node, cancellationToken))
             {
-                return false;
+                return null;
             }
 
             var tree = model.SyntaxTree;
-            var span = GetDiagnosticSpan(node);
-            if (tree.OverlapsHiddenPosition(span, cancellationToken))
+            if (tree.OverlapsHiddenPosition(node.Span, cancellationToken))
             {
-                return false;
+                return null;
             }
 
-            diagnostic = Diagnostic.Create(s_descriptor, tree.GetLocation(span));
-            return true;
+            return Diagnostic.Create(
+                UnnecessaryWithSuggestionDescriptor, 
+                node.SyntaxTree.GetLocation(GetFadeSpan(node)),
+                ImmutableArray.Create(node.GetLocation()));
         }
-
-        public DiagnosticAnalyzerCategory GetAnalyzerCategory()
-            => DiagnosticAnalyzerCategory.SemanticSpanAnalysis;
     }
 }

src/Features/VisualBasic/Portable/CodeFixes/RemoveUnnecessaryCast/RemoveUnnecessaryCastCodeFixProvider.RemoveUnnecessaryCastFixAllProvider.vb

-' Copyright (c) Microsoft.  All Rights Reserved.  Licensed under the Apache License, Version 2.0.  See License.txt in the project root for license information.
-
-Imports System.Threading
-Imports Microsoft.CodeAnalysis.CodeFixes
-Imports Microsoft.CodeAnalysis.Options
-Imports Microsoft.CodeAnalysis.VisualBasic.Syntax
-
-Namespace Microsoft.CodeAnalysis.VisualBasic.CodeFixes.RemoveUnnecessaryCast
-    Partial Friend Class RemoveUnnecessaryCastCodeFixProvider
-        Inherits CodeFixProvider
-
-        Private Class RemoveUnnecessaryCastFixAllProvider
-            Inherits BatchSimplificationFixAllProvider
-
-            Friend Shared Shadows ReadOnly Instance As RemoveUnnecessaryCastFixAllProvider = New RemoveUnnecessaryCastFixAllProvider()
-
-            Protected Overrides Function GetNodeToSimplify(root As SyntaxNode, model As SemanticModel, diagnostic As Diagnostic, options As DocumentOptionSet, ByRef codeActionId As String, cancellationToken As CancellationToken) As SyntaxNode
-                codeActionId = Nothing
-                Return GetCastNode(root, model, diagnostic.Location.SourceSpan, cancellationToken)
-            End Function
-
-            Protected Overrides ReadOnly Property NeedsParentFixup As Boolean
-                Get
-                    Return True
-                End Get
-            End Property
-
-            Protected Overrides Async Function AddSimplifyAnnotationsAsync(document As Document, nodeToSimplify As SyntaxNode, cancellationToken As CancellationToken) As Task(Of Document)
-                Dim cast = TryCast(nodeToSimplify, ExpressionSyntax)
-                If cast Is Nothing Then
-                    Return document
-                End If
-
-                Return Await RemoveUnnecessaryCastAsync(document, cast, cancellationToken).ConfigureAwait(False)
-            End Function
-        End Class
-    End Class
-End Namespace

src/Features/VisualBasic/Portable/CodeFixes/RemoveUnnecessaryCast/RemoveUnnecessaryCastCodeFixProvider.Rewriter.vb

-' Copyright (c) Microsoft.  All Rights Reserved.  Licensed under the Apache License, Version 2.0.  See License.txt in the project root for license information.
-
-Imports Microsoft.CodeAnalysis
-Imports Microsoft.CodeAnalysis.Simplification
-Imports Microsoft.CodeAnalysis.VisualBasic.Syntax
-
-Namespace Microsoft.CodeAnalysis.VisualBasic.CodeFixes.RemoveUnnecessaryCast
-    Partial Friend Class RemoveUnnecessaryCastCodeFixProvider
-        Partial Private Class Rewriter
-            Inherits VisualBasicSyntaxRewriter
-
-            Private ReadOnly _castExpression As ExpressionSyntax
-
-            Public Sub New(castExpression As ExpressionSyntax)
-                _castExpression = castExpression
-            End Sub
-
-            Private Shared Function GetExpression(expression As ExpressionSyntax) As ExpressionSyntax
-                If TypeOf expression Is ParenthesizedExpressionSyntax Then
-                    Return expression.WithAdditionalAnnotations(Simplifier.Annotation)
-                Else
-                    Return expression
-                End If
-            End Function
-
-            Public Overrides Function VisitCTypeExpression(node As CTypeExpressionSyntax) As SyntaxNode
-                If node Is _castExpression Then
-                    Return node.WithExpression(GetExpression(node.Expression)) _
-                               .WithAdditionalAnnotations(Simplifier.Annotation) _
-                               .Parenthesize()
-                End If
-
-                Return MyBase.VisitCTypeExpression(node)
-            End Function
-
-            Public Overrides Function VisitDirectCastExpression(node As DirectCastExpressionSyntax) As SyntaxNode
-                If node Is _castExpression Then
-                    Return node.WithExpression(GetExpression(node.Expression)) _
-                               .WithAdditionalAnnotations(Simplifier.Annotation) _
-                               .Parenthesize()
-                End If
-
-                Return MyBase.VisitDirectCastExpression(node)
-            End Function
-
-            Public Overrides Function VisitTryCastExpression(node As TryCastExpressionSyntax) As SyntaxNode
-                If node Is _castExpression Then
-                    Return node.WithExpression(GetExpression(node.Expression)) _
-                               .WithAdditionalAnnotations(Simplifier.Annotation) _
-                               .Parenthesize()
-                End If
-
-                Return MyBase.VisitTryCastExpression(node)
-            End Function
-
-            Public Overrides Function VisitPredefinedCastExpression(node As PredefinedCastExpressionSyntax) As SyntaxNode
-                If node Is _castExpression Then
-                    Return node.WithExpression(GetExpression(node.Expression)) _
-                               .WithAdditionalAnnotations(Simplifier.Annotation) _
-                               .Parenthesize()
-                End If
-
-                Return MyBase.VisitPredefinedCastExpression(node)
-            End Function
-        End Class
-    End Class
-End Namespace

src/Features/VisualBasic/Portable/CodeFixes/RemoveUnnecessaryCast/RemoveUnnecessaryCastCodeFixProvider.vb

@@ -3,57 +3,31 @@
 Imports System.Collections.Immutable
 Imports System.Composition
 Imports System.Threading
+Imports Microsoft.CodeAnalysis
 Imports Microsoft.CodeAnalysis.CodeActions
 Imports Microsoft.CodeAnalysis.CodeFixes
 Imports Microsoft.CodeAnalysis.Diagnostics
+Imports Microsoft.CodeAnalysis.Editing
 Imports Microsoft.CodeAnalysis.Formatting
 Imports Microsoft.CodeAnalysis.Simplification
-Imports Microsoft.CodeAnalysis.Text
 Imports Microsoft.CodeAnalysis.VisualBasic.Syntax
 
 Namespace Microsoft.CodeAnalysis.VisualBasic.CodeFixes.RemoveUnnecessaryCast
 
-    <ExportCodeFixProviderAttribute(LanguageNames.VisualBasic, Name:=PredefinedCodeFixProviderNames.RemoveUnnecessaryCast), [Shared]>
+    <ExportCodeFixProvider(LanguageNames.VisualBasic, Name:=PredefinedCodeFixProviderNames.RemoveUnnecessaryCast), [Shared]>
     <ExtensionOrder(After:=PredefinedCodeFixProviderNames.GenerateEndConstruct)>
     Partial Friend Class RemoveUnnecessaryCastCodeFixProvider
-        Inherits CodeFixProvider
+        Inherits SyntaxEditorBasedCodeFixProvider
 
-        Public NotOverridable Overrides ReadOnly Property FixableDiagnosticIds As ImmutableArray(Of String)
-            Get
-                Return ImmutableArray.Create(IDEDiagnosticIds.RemoveUnnecessaryCastDiagnosticId)
-            End Get
-        End Property
+        Public NotOverridable Overrides ReadOnly Property FixableDiagnosticIds As ImmutableArray(Of String) =
+            ImmutableArray.Create(IDEDiagnosticIds.RemoveUnnecessaryCastDiagnosticId)
 
-        Public NotOverridable Overrides Async Function RegisterCodeFixesAsync(context As CodeFixContext) As Task
-            Dim document = context.Document
-            Dim span = context.Span
-            Dim cancellationToken = context.CancellationToken
-
-            Dim root = Await document.GetSyntaxRootAsync(cancellationToken).ConfigureAwait(False)
-            Dim model = DirectCast(Await document.GetSemanticModelAsync(cancellationToken).ConfigureAwait(False), SemanticModel)
-
-            Dim node = GetCastNode(root, model, span, cancellationToken)
-            If node Is Nothing Then
-                Return
-            End If
-
-            context.RegisterCodeFix(
-                New MyCodeAction(
-                    VBFeaturesResources.Remove_Unnecessary_Cast,
-                    Function(c) RemoveUnnecessaryCastAsync(document, node, c)),
+        Public Overrides Function RegisterCodeFixesAsync(context As CodeFixContext) As Task
+            context.RegisterCodeFix(New MyCodeAction(
+                FeaturesResources.Remove_Unnecessary_Cast,
+                Function(c) FixAsync(context.Document, context.Diagnostics.First(), c)),
                 context.Diagnostics)
-        End Function
-
-        Private Shared Function GetCastNode(root As SyntaxNode, model As SemanticModel, span As TextSpan, cancellationToken As CancellationToken) As ExpressionSyntax
-            Dim token = root.FindToken(span.Start)
-            If Not token.Span.IntersectsWith(span) Then
-                Return Nothing
-            End If
-
-            Dim node = token.GetAncestors(Of ExpressionSyntax)() _
-                            .Where(Function(c) TypeOf c Is CastExpressionSyntax OrElse TypeOf c Is PredefinedCastExpressionSyntax) _
-                            .FirstOrDefault(Function(c) c.Span.IntersectsWith(span) AndAlso IsUnnecessaryCast(c, model, cancellationToken))
-            Return node
+            Return SpecializedTasks.EmptyTask
         End Function
 
         Private Shared Function IsUnnecessaryCast(node As ExpressionSyntax, model As SemanticModel, cancellationToken As CancellationToken) As Boolean
@@ -70,117 +44,116 @@ Namespace Microsoft.CodeAnalysis.VisualBasic.CodeFixes.RemoveUnnecessaryCast
             Return False
         End Function
 
-        Private Shared Async Function RemoveUnnecessaryCastAsync(document As Document, node As ExpressionSyntax, cancellationToken As CancellationToken) As Task(Of Document)
-            ' First, annotate our expression so that we can get back to it.
-            Dim updatedDocument = Await document.ReplaceNodeAsync(node, node.WithAdditionalAnnotations(s_expressionAnnotation), cancellationToken).ConfigureAwait(False)
-
-            Dim expression = Await FindNodeWithAnnotationAsync(Of ExpressionSyntax)(s_expressionAnnotation, updatedDocument, cancellationToken).ConfigureAwait(False)
-
-            ' Next, make the parenting statement of the expression semantically explicit
-            Dim parentStatement = expression.FirstAncestorOrSelf(Of StatementSyntax)()
-            Dim explicitParentStatement = Await Simplifier.ExpandAsync(parentStatement, updatedDocument, cancellationToken:=cancellationToken).ConfigureAwait(False)
-            explicitParentStatement = explicitParentStatement.WithAdditionalAnnotations(Formatter.Annotation, s_statementAnnotation)
+        Protected Overrides Async Function FixAllAsync(
+            document As Document, diagnostics As ImmutableArray(Of Diagnostic),
+            editor As SyntaxEditor, cancellationToken As CancellationToken) As Task
+
+            ' VB parsing is extremely hairy.  Unlike C#, it can be very dangerous to go and remove a
+            ' cast.  For example, if the cast is at the statement level, it may contain an
+            ' expression that itself is not legal on its own at the top level (see below for an
+            ' example of this).  Similarly, removing the cast may make VB parse following code
+            ' differently.
+            '
+            ' In order to deal with all these concerns safely, we first complexify the surrounding
+            ' statements containing the casts we want to remove.  *Then* we  remove the casts from
+            ' inside that.
+            '
+            ' As an example, consider:                  DirectCast(New Goo(), IGoo).Blah() This is
+            ' legal code, but this is not:              New Goo().Blah()
+            '
+            ' (because 'new' cannot start a statement).
+            ' So we need to instead generate:           Call New Goo().Blah()
+
+            Dim originalCastNodes = diagnostics.SelectAsArray(
+                Function(d) DirectCast(d.AdditionalLocations(0).FindNode(getInnermostNodeForTie:=True, cancellationToken), ExpressionSyntax))
+
+            ' Keep track of the all the casts we want to fix up.  We'll fix them up at the end
+            ' after we've done all other manipulation.
+            Dim trackedRoot = editor.OriginalRoot.TrackNodes(originalCastNodes)
+            Dim trackedDocument = document.WithSyntaxRoot(trackedRoot)
+
+            ' Now, go and expand all the containing statements of the nodes we want to edit.
+            ' This is necessary to ensure that the code remains parseable and preserves semantics.
+            Dim expandedRoot = Await ExpandSurroundingStatementsAsync(trackedDocument, originalCastNodes, cancellationToken).ConfigureAwait(False)
+            Dim expandedDocument = document.WithSyntaxRoot(expandedRoot)
+
+            Dim removedRoot = Await RemoveCasts(
+                expandedDocument, originalCastNodes, cancellationToken).ConfigureAwait(False)
+
+            editor.ReplaceNode(editor.OriginalRoot, removedRoot)
+        End Function
 
-            updatedDocument = Await updatedDocument.ReplaceNodeAsync(parentStatement, explicitParentStatement, cancellationToken).ConfigureAwait(False)
+        Private Async Function RemoveCasts(
+                document As Document, originalCastNodes As ImmutableArray(Of ExpressionSyntax),
+                cancellationToken As CancellationToken) As Task(Of SyntaxNode)
 
-            ' Next, make the statement after the parenting statement of the expression semantically explicit.
-            parentStatement = Await FindNodeWithAnnotationAsync(Of StatementSyntax)(s_statementAnnotation, updatedDocument, cancellationToken).ConfigureAwait(False)
-            Dim nextStatement = parentStatement.GetNextStatement()
-            If nextStatement IsNot Nothing Then
-                Dim explicitNextStatement = Await Simplifier.ExpandAsync(nextStatement, updatedDocument, cancellationToken:=cancellationToken).ConfigureAwait(False)
-                updatedDocument = Await updatedDocument.ReplaceNodeAsync(nextStatement, explicitNextStatement, cancellationToken).ConfigureAwait(False)
-            End If
+            Dim root = Await document.GetSyntaxRootAsync(cancellationToken).ConfigureAwait(False)
 
-            updatedDocument = Await RewriteCoreAsync(updatedDocument, expression, cancellationToken).ConfigureAwait(False)
+            ' Now, find the cast nodes again in the expanded document
+            Dim currentCastNodes = root.GetCurrentNodes(originalCastNodes)
 
-            ' Remove added _expressionAnnotation and _statementAnnotation.
-            updatedDocument = Await RemoveNodesAndTokensWithAnnotationAsync(s_expressionAnnotation, updatedDocument, cancellationToken).ConfigureAwait(False)
-            updatedDocument = Await RemoveNodesAndTokensWithAnnotationAsync(s_statementAnnotation, updatedDocument, cancellationToken).ConfigureAwait(False)
+            Dim innerEditor = New SyntaxEditor(root, document.Project.Solution.Workspace)
+            Await innerEditor.ApplyExpressionLevelSemanticEditsAsync(
+                document, currentCastNodes.ToImmutableArray(),
+                Function(semanticModel, castExpression) IsUnnecessaryCast(castExpression, semanticModel, cancellationToken),
+                Function(unused, currentRoot, castExpression)
+                    Dim newCastExpression = Uncast(castExpression).WithAdditionalAnnotations(Formatter.Annotation)
+                    Return currentRoot.ReplaceNode(castExpression, newCastExpression)
+                End Function,
+                cancellationToken).ConfigureAwait(False)
 
-            Return updatedDocument
+            Return innerEditor.GetChangedRoot()
         End Function
 
-        Private Shared Async Function RemoveNodesAndTokensWithAnnotationAsync(annotation As SyntaxAnnotation, document As Document, cancellationToken As CancellationToken) As Task(Of Document)
+        Private Shared Async Function ExpandSurroundingStatementsAsync(
+                document As Document, originalNodes As ImmutableArray(Of ExpressionSyntax),
+                cancellationToken As CancellationToken) As Task(Of SyntaxNode)
+
+            Dim semanticModel = Await document.GetSemanticModelAsync(cancellationToken).ConfigureAwait(False)
             Dim root = Await document.GetSyntaxRootAsync(cancellationToken).ConfigureAwait(False)
-            Dim nodesWithAnnotation = Await FindNodesWithAnnotationAsync(annotation, document, cancellationToken).ConfigureAwait(False)
-            root = root.ReplaceSyntax(
-                nodesWithAnnotation.Where(Function(n) n.IsNode).Select(Function(n) n.AsNode),
-                Function(o, n) o.WithoutAnnotations(annotation),
-                nodesWithAnnotation.Where(Function(n) n.IsToken).Select(Function(n) n.AsToken),
-                Function(o, n) o.WithoutAnnotations(annotation),
-                SpecializedCollections.EmptyEnumerable(Of SyntaxTrivia),
-                Nothing)
-            Return document.WithSyntaxRoot(root)
-        End Function
 
-        Private Shared Async Function RewriteCoreAsync(document As Document, originalExpr As ExpressionSyntax, cancellationToken As CancellationToken) As Task(Of Document)
-            ' Finally, rewrite the cast expression
-            Dim exprToRewrite As ExpressionSyntax = Nothing
-            Dim annotatedNodes = Await FindNodesWithAnnotationAsync(s_expressionAnnotation, document, cancellationToken).ConfigureAwait(False)
-
-            For Each annotatedNode In annotatedNodes
-                exprToRewrite = TryCast(annotatedNode.AsNode, ExpressionSyntax)
-                If exprToRewrite IsNot Nothing AndAlso exprToRewrite.IsKind(originalExpr.Kind) Then
-                    If annotatedNodes.Count > 1 Then
-                        ' Ensure cast is unnecessary
-                        Dim model = Await document.GetSemanticModelAsync(cancellationToken).ConfigureAwait(False)
-                        If IsUnnecessaryCast(exprToRewrite, model, cancellationToken) Then
-                            Exit For
-                        End If
-                    Else
-                        Exit For
-                    End If
-                End If
-                exprToRewrite = Nothing
+            ' Note: we not only get the containing statement, but also the next statement after
+            ' that.  That's because the removal of the parens in the cast may then cause parsing
+            ' problems with VB consuming the following line into the current line.  This is most
+            ' common with query clauses.  By complexifying the next statement, we prevent that from
+            ' happening.
+            Dim trackedNodes = root.GetCurrentNodes(originalNodes)
+            Dim containingAndNextStatements = trackedNodes.SelectMany(
+                Function(n)
+                    Dim containingStatement = n.GetAncestorOrThis(Of StatementSyntax)
+                    Dim nextStatement = containingStatement.GetNextStatement()
+                    Return If(nextStatement Is Nothing,
+                        {containingStatement},
+                        {containingStatement, nextStatement})
+                End Function).Distinct()
+
+            Dim workspace = document.Project.Solution.Workspace
+            Dim editor = New SyntaxEditor(root, workspace)
+
+            For Each containingStatement In containingAndNextStatements
+                Dim expandedStatement = Simplifier.Expand(
+                    containingStatement, semanticModel, workspace,
+                    cancellationToken:=cancellationToken)
+                editor.ReplaceNode(containingStatement, expandedStatement)
             Next
 
-            If exprToRewrite Is Nothing Then
-                Return document
-            End If
-
-            Dim rewriter = New Rewriter(exprToRewrite)
-            Dim newExpression = rewriter.Visit(exprToRewrite)
-
-            ' Remove the annotation from the expression so that it isn't hanging around later.
-            If newExpression.HasAnnotation(s_expressionAnnotation) Then
-
-                newExpression = newExpression.WithoutAnnotations(s_expressionAnnotation)
-
-            ElseIf newExpression.IsKind(SyntaxKind.ParenthesizedExpression) Then
-
-                Dim parenthesizedExpression = DirectCast(newExpression, ParenthesizedExpressionSyntax)
-                If parenthesizedExpression.Expression.HasAnnotation(s_expressionAnnotation) Then
-                    newExpression = parenthesizedExpression _
-                        .WithExpression(parenthesizedExpression.Expression.WithoutAnnotations(s_expressionAnnotation))
-                End If
+            Return editor.GetChangedRoot()
+        End Function
 
+        Private Function Uncast(old As ExpressionSyntax) As ExpressionSyntax
+            ' parenthesize the uncasted value to help ensure any proper parsing. The excess
+            ' parens will be removed if unnecessary. 
+            Dim castExpression = TryCast(old, CastExpressionSyntax)
+            If castExpression IsNot Nothing Then
+                Return castExpression.Uncast().Parenthesize()
             End If
 
-            document = Await document.ReplaceNodeAsync(exprToRewrite, newExpression, cancellationToken).ConfigureAwait(False)
-
-            If annotatedNodes.Count > 1 Then
-                Return Await RewriteCoreAsync(document, originalExpr, cancellationToken).ConfigureAwait(False)
+            Dim predefinedCastExpression = TryCast(old, PredefinedCastExpressionSyntax)
+            If predefinedCastExpression IsNot Nothing Then
+                Return predefinedCastExpression.Uncast().Parenthesize()
             End If
 
-            Return document
-        End Function
-
-        Private Shared ReadOnly s_expressionAnnotation As New SyntaxAnnotation
-        Private Shared ReadOnly s_statementAnnotation As New SyntaxAnnotation
-
-        Private Shared Async Function FindNodeWithAnnotationAsync(Of T As SyntaxNode)(annotation As SyntaxAnnotation, document As Document, cancellationToken As CancellationToken) As Task(Of T)
-            Dim annotatedNodes = Await FindNodesWithAnnotationAsync(annotation, document, cancellationToken).ConfigureAwait(False)
-            Dim result = annotatedNodes.Single().AsNode()
-            Return DirectCast(result, T)
-        End Function
-
-        Private Shared Async Function FindNodesWithAnnotationAsync(annotation As SyntaxAnnotation, document As Document, cancellationToken As CancellationToken) As Task(Of IEnumerable(Of SyntaxNodeOrToken))
-            Dim root = Await document.GetSyntaxRootAsync(cancellationToken).ConfigureAwait(False)
-            Return root.GetAnnotatedNodesAndTokens(annotation)
-        End Function
-
-        Public NotOverridable Overrides Function GetFixAllProvider() As FixAllProvider
-            Return RemoveUnnecessaryCastFixAllProvider.Instance
+            Throw ExceptionUtilities.UnexpectedValue(old)
         End Function
 
         Private Class MyCodeAction

src/Features/VisualBasic/Portable/Diagnostics/Analyzers/VisualBasicRemoveUnnecessaryCastDiagnosticAnalyzer.vb

@@ -11,19 +11,15 @@ Namespace Microsoft.CodeAnalysis.VisualBasic.Diagnostics.RemoveUnnecessaryCast
 
     <DiagnosticAnalyzer(LanguageNames.VisualBasic)>
     Friend NotInheritable Class VisualBasicRemoveUnnecessaryCastDiagnosticAnalyzer
-        Inherits RemoveUnnecessaryCastDiagnosticAnalyzerBase(Of SyntaxKind)
+        Inherits RemoveUnnecessaryCastDiagnosticAnalyzerBase(Of SyntaxKind, ExpressionSyntax)
 
-        Private Shared ReadOnly s_kindsOfInterest As ImmutableArray(Of SyntaxKind) = ImmutableArray.Create(SyntaxKind.CTypeExpression,
-                                                                                                          SyntaxKind.DirectCastExpression,
-                                                                                                          SyntaxKind.TryCastExpression,
-                                                                                                          SyntaxKind.PredefinedCastExpression)
-        Public Overrides ReadOnly Property SyntaxKindsOfInterest As ImmutableArray(Of SyntaxKind)
-            Get
-                Return s_kindsOfInterest
-            End Get
-        End Property
+        Protected Overrides ReadOnly Property SyntaxKindsOfInterest As ImmutableArray(Of SyntaxKind) =
+            ImmutableArray.Create(SyntaxKind.CTypeExpression,
+                                  SyntaxKind.DirectCastExpression,
+                                  SyntaxKind.TryCastExpression,
+                                  SyntaxKind.PredefinedCastExpression)
 
-        Protected Overrides Function IsUnnecessaryCast(model As SemanticModel, node As SyntaxNode, cancellationToken As CancellationToken) As Boolean
+        Protected Overrides Function IsUnnecessaryCast(model As SemanticModel, node As ExpressionSyntax, cancellationToken As CancellationToken) As Boolean
             Select Case node.Kind
                 Case SyntaxKind.CTypeExpression, SyntaxKind.DirectCastExpression, SyntaxKind.TryCastExpression
                     Return DirectCast(node, CastExpressionSyntax).IsUnnecessaryCast(model, assumeCallKeyword:=True, cancellationToken:=cancellationToken)
@@ -34,15 +30,8 @@ Namespace Microsoft.CodeAnalysis.VisualBasic.Diagnostics.RemoveUnnecessaryCast
             End Select
         End Function
 
-        Protected Overrides Function GetDiagnosticSpan(node As SyntaxNode) As TextSpan
-            Select Case node.Kind
-                Case SyntaxKind.CTypeExpression, SyntaxKind.DirectCastExpression, SyntaxKind.TryCastExpression
-                    Return DirectCast(node, CastExpressionSyntax).Keyword.Span
-                Case SyntaxKind.PredefinedCastExpression
-                    Return DirectCast(node, PredefinedCastExpressionSyntax).Keyword.Span
-                Case Else
-                    Throw ExceptionUtilities.UnexpectedValue(node.Kind)
-            End Select
+        Protected Overrides Function GetFadeSpan(node As ExpressionSyntax) As TextSpan
+            Return node.GetFirstToken().Span
         End Function
     End Class
 End Namespace

src/Features/VisualBasic/Portable/VBFeaturesResources.Designer.vb

@@ -240,15 +240,6 @@ Namespace Microsoft.CodeAnalysis.VisualBasic.VBFeaturesResources
             End Get
         End Property
         
-        '''<summary>
-        '''  Looks up a localized string similar to Cast is redundant.
-        '''</summary>
-        Friend ReadOnly Property Cast_is_redundant() As String
-            Get
-                Return ResourceManager.GetString("Cast_is_redundant", resourceCulture)
-            End Get
-        End Property
-        
         '''<summary>
         '''  Looks up a localized string similar to Catch clause.
         '''</summary>
@@ -2009,15 +2000,6 @@ Namespace Microsoft.CodeAnalysis.VisualBasic.VBFeaturesResources
             End Get
         End Property
         
-        '''<summary>
-        '''  Looks up a localized string similar to Remove Unnecessary Cast.
-        '''</summary>
-        Friend ReadOnly Property Remove_Unnecessary_Cast() As String
-            Get
-                Return ResourceManager.GetString("Remove_Unnecessary_Cast", resourceCulture)
-            End Get
-        End Property
-        
         '''<summary>
         '''  Looks up a localized string similar to Remove Unnecessary Imports.
         '''</summary>

src/Features/VisualBasic/Portable/VBFeaturesResources.resx

@@ -213,12 +213,6 @@
   <data name="Fix_Incorrect_Function_Return_Type" xml:space="preserve">
     <value>Fix Incorrect Function Return Type</value>
   </data>
-  <data name="Remove_Unnecessary_Cast" xml:space="preserve">
-    <value>Remove Unnecessary Cast</value>
-  </data>
-  <data name="Cast_is_redundant" xml:space="preserve">
-    <value>Cast is redundant</value>
-  </data>
   <data name="Simplify_name_0" xml:space="preserve">
     <value>Simplify name '{0}'</value>
   </data>

src/Features/VisualBasic/Portable/xlf/VBFeaturesResources.cs.xlf

@@ -157,16 +157,6 @@
         <target state="translated">Opravit nesprávný návratový typ funkce</target>
         <note />
       </trans-unit>
-      <trans-unit id="Remove_Unnecessary_Cast">
-        <source>Remove Unnecessary Cast</source>
-        <target state="translated">Odebrat nepotřebné přetypování</target>
-        <note />
-      </trans-unit>
-      <trans-unit id="Cast_is_redundant">
-        <source>Cast is redundant</source>
-        <target state="translated">Přetypování je redundantní.</target>
-        <note />
-      </trans-unit>
       <trans-unit id="Simplify_name_0">
         <source>Simplify name '{0}'</source>
         <target state="translated">Zjednodušit název {0}</target>

src/Features/VisualBasic/Portable/xlf/VBFeaturesResources.de.xlf

@@ -157,16 +157,6 @@
         <target state="translated">Rückgabetyp für unzulässige Funktion beheben</target>
         <note />
       </trans-unit>
-      <trans-unit id="Remove_Unnecessary_Cast">
-        <source>Remove Unnecessary Cast</source>
-        <target state="translated">Nicht erforderliche Umwandlung entfernen</target>
-        <note />
-      </trans-unit>
-      <trans-unit id="Cast_is_redundant">
-        <source>Cast is redundant</source>
-        <target state="translated">Cast ist redundant</target>
-        <note />
-      </trans-unit>
       <trans-unit id="Simplify_name_0">
         <source>Simplify name '{0}'</source>
         <target state="translated">Name '{0}' vereinfachen</target>

src/Features/VisualBasic/Portable/xlf/VBFeaturesResources.es.xlf

@@ -157,16 +157,6 @@
         <target state="translated">Corregir tipo devuelto de función incorrecto</target>
         <note />
       </trans-unit>
-      <trans-unit id="Remove_Unnecessary_Cast">
-        <source>Remove Unnecessary Cast</source>
-        <target state="translated">Quitar conversión innecesaria</target>
-        <note />
-      </trans-unit>
-      <trans-unit id="Cast_is_redundant">
-        <source>Cast is redundant</source>
-        <target state="translated">Cast es redundante</target>
-        <note />
-      </trans-unit>
       <trans-unit id="Simplify_name_0">
         <source>Simplify name '{0}'</source>
         <target state="translated">Simplificar nombre '{0}'</target>

src/Features/VisualBasic/Portable/xlf/VBFeaturesResources.fr.xlf

@@ -157,16 +157,6 @@
         <target state="translated">Corriger le type de retour de fonction incorrect</target>
         <note />
       </trans-unit>
-      <trans-unit id="Remove_Unnecessary_Cast">
-        <source>Remove Unnecessary Cast</source>
-        <target state="translated">Supprimer le cast inutile</target>
-        <note />
-      </trans-unit>
-      <trans-unit id="Cast_is_redundant">
-        <source>Cast is redundant</source>
-        <target state="translated">Cast redondant</target>
-        <note />
-      </trans-unit>
       <trans-unit id="Simplify_name_0">
         <source>Simplify name '{0}'</source>
         <target state="translated">Simplifier le nom '{0}'</target>

src/Features/VisualBasic/Portable/xlf/VBFeaturesResources.it.xlf

@@ -157,16 +157,6 @@
         <target state="translated">Correggi tipo errato restituito da funzione</target>
         <note />
       </trans-unit>
-      <trans-unit id="Remove_Unnecessary_Cast">
-        <source>Remove Unnecessary Cast</source>
-        <target state="translated">Rimuovi cast non necessario</target>
-        <note />
-      </trans-unit>
-      <trans-unit id="Cast_is_redundant">
-        <source>Cast is redundant</source>
-        <target state="translated">Il cast è ridondante</target>
-        <note />
-      </trans-unit>
       <trans-unit id="Simplify_name_0">
         <source>Simplify name '{0}'</source>
         <target state="translated">Semplifica il nome '{0}'</target>

src/Features/VisualBasic/Portable/xlf/VBFeaturesResources.ja.xlf

@@ -157,16 +157,6 @@
         <target state="translated">無効な関数の戻り値の型を修正する</target>
         <note />
       </trans-unit>
-      <trans-unit id="Remove_Unnecessary_Cast">
-        <source>Remove Unnecessary Cast</source>
-        <target state="translated">不要なキャストの削除</target>
-        <note />
-      </trans-unit>
-      <trans-unit id="Cast_is_redundant">
-        <source>Cast is redundant</source>
-        <target state="translated">キャストが冗長です</target>
-        <note />
-      </trans-unit>
       <trans-unit id="Simplify_name_0">
         <source>Simplify name '{0}'</source>
         <target state="translated">名前 '{0}' の単純化</target>

src/Features/VisualBasic/Portable/xlf/VBFeaturesResources.ko.xlf

@@ -157,16 +157,6 @@
         <target state="translated">잘못된 함수 반환 형식 수정</target>
         <note />
       </trans-unit>
-      <trans-unit id="Remove_Unnecessary_Cast">
-        <source>Remove Unnecessary Cast</source>
-        <target state="translated">불필요한 캐스트 제거</target>
-        <note />
-      </trans-unit>
-      <trans-unit id="Cast_is_redundant">
-        <source>Cast is redundant</source>
-        <target state="translated">캐스팅이 중복됩니다.</target>
-        <note />
-      </trans-unit>
       <trans-unit id="Simplify_name_0">
         <source>Simplify name '{0}'</source>
         <target state="translated">{0}' 이름 단순화</target>

src/Features/VisualBasic/Portable/xlf/VBFeaturesResources.pl.xlf

@@ -157,16 +157,6 @@
         <target state="translated">Napraw nieprawidłowy typ zwracany funkcji</target>
         <note />
       </trans-unit>
-      <trans-unit id="Remove_Unnecessary_Cast">
-        <source>Remove Unnecessary Cast</source>
-        <target state="translated">Usuń niepotrzebne rzutowanie</target>
-        <note />
-      </trans-unit>
-      <trans-unit id="Cast_is_redundant">
-        <source>Cast is redundant</source>
-        <target state="translated">Nadmiarowe określenie elementu Cast</target>
-        <note />
-      </trans-unit>
       <trans-unit id="Simplify_name_0">
         <source>Simplify name '{0}'</source>
         <target state="translated">Uprość nazwę „{0}”</target>

src/Features/VisualBasic/Portable/xlf/VBFeaturesResources.pt-BR.xlf

@@ -157,16 +157,6 @@
         <target state="translated">Corrigir Tipo de Retorno de Função Incorreta</target>
         <note />
       </trans-unit>
-      <trans-unit id="Remove_Unnecessary_Cast">
-        <source>Remove Unnecessary Cast</source>
-        <target state="translated">Remover Conversão Desnecessária</target>
-        <note />
-      </trans-unit>
-      <trans-unit id="Cast_is_redundant">
-        <source>Cast is redundant</source>
-        <target state="translated">A conversão é redundante</target>
-        <note />
-      </trans-unit>
       <trans-unit id="Simplify_name_0">
         <source>Simplify name '{0}'</source>
         <target state="translated">Simplificar nome '{0}'</target>

src/Features/VisualBasic/Portable/xlf/VBFeaturesResources.ru.xlf

@@ -157,16 +157,6 @@
         <target state="translated">Исправить неверный тип возвращения функции</target>
         <note />
       </trans-unit>
-      <trans-unit id="Remove_Unnecessary_Cast">
-        <source>Remove Unnecessary Cast</source>
-        <target state="translated">Удалить ненужное приведение</target>
-        <note />
-      </trans-unit>
-      <trans-unit id="Cast_is_redundant">
-        <source>Cast is redundant</source>
-        <target state="translated">Приведение избыточно</target>
-        <note />
-      </trans-unit>
       <trans-unit id="Simplify_name_0">
         <source>Simplify name '{0}'</source>
         <target state="translated">Упрощение имени "{0}"</target>

src/Features/VisualBasic/Portable/xlf/VBFeaturesResources.tr.xlf

@@ -157,16 +157,6 @@
         <target state="translated">Hatalı İşlev Dönüş Türünü Düzelt</target>
         <note />
       </trans-unit>
-      <trans-unit id="Remove_Unnecessary_Cast">
-        <source>Remove Unnecessary Cast</source>
-        <target state="translated">Gereksiz Atamayı Kaldır</target>
-        <note />
-      </trans-unit>
-      <trans-unit id="Cast_is_redundant">
-        <source>Cast is redundant</source>
-        <target state="translated">Atama gereksiz</target>
-        <note />
-      </trans-unit>
       <trans-unit id="Simplify_name_0">
         <source>Simplify name '{0}'</source>
         <target state="translated">{0}' adını basitleştir</target>

src/Features/VisualBasic/Portable/xlf/VBFeaturesResources.zh-Hans.xlf

@@ -157,16 +157,6 @@
         <target state="translated">修复不正确的函数返回类型</target>
         <note />
       </trans-unit>
-      <trans-unit id="Remove_Unnecessary_Cast">
-        <source>Remove Unnecessary Cast</source>
-        <target state="translated">删除不必要的转换</target>
-        <note />
-      </trans-unit>
-      <trans-unit id="Cast_is_redundant">
-        <source>Cast is redundant</source>
-        <target state="translated">强制转换是多余的</target>
-        <note />
-      </trans-unit>
       <trans-unit id="Simplify_name_0">
         <source>Simplify name '{0}'</source>
         <target state="translated">简化名称“{0}”</target>

src/Features/VisualBasic/Portable/xlf/VBFeaturesResources.zh-Hant.xlf

@@ -157,16 +157,6 @@
         <target state="translated">修正不正確的函式傳回類型</target>
         <note />
       </trans-unit>
-      <trans-unit id="Remove_Unnecessary_Cast">
-        <source>Remove Unnecessary Cast</source>
-        <target state="translated">移除不必要的 Cast</target>
-        <note />
-      </trans-unit>
-      <trans-unit id="Cast_is_redundant">
-        <source>Cast is redundant</source>
-        <target state="translated">Cast 是多餘的</target>
-        <note />
-      </trans-unit>
       <trans-unit id="Simplify_name_0">
         <source>Simplify name '{0}'</source>
         <target state="translated">簡化名稱 '{0}'</target>

src/Workspaces/CSharp/Portable/Extensions/CastExpressionSyntaxExtensions.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.Diagnostics;
+using System.Linq;
 using System.Threading;
 using Microsoft.CodeAnalysis.CSharp.Symbols;
 using Microsoft.CodeAnalysis.CSharp.Syntax;
 using Microsoft.CodeAnalysis.CSharp.Utilities;
+using Microsoft.CodeAnalysis.Formatting;
 using Microsoft.CodeAnalysis.Shared.Extensions;
+using Microsoft.CodeAnalysis.Simplification;
 
 namespace Microsoft.CodeAnalysis.CSharp.Extensions
 {
@@ -621,5 +623,28 @@ private static bool IsRequiredImplicitNumericConversion(ITypeSymbol sourceType,
                     return false;
             }
         }
+
+        public static ExpressionSyntax Uncast(this CastExpressionSyntax node)
+        {
+            var leadingTrivia = node.OpenParenToken.LeadingTrivia
+                .Concat(node.OpenParenToken.TrailingTrivia)
+                .Concat(node.Type.GetLeadingTrivia())
+                .Concat(node.Type.GetTrailingTrivia())
+                .Concat(node.CloseParenToken.LeadingTrivia)
+                .Concat(node.CloseParenToken.TrailingTrivia)
+                .Concat(node.Expression.GetLeadingTrivia())
+                .Where(t => !t.IsElastic());
+
+            var trailingTrivia = node.GetTrailingTrivia().Where(t => !t.IsElastic());
+
+            var resultNode = node.Expression
+                .WithLeadingTrivia(leadingTrivia)
+                .WithTrailingTrivia(trailingTrivia)
+                .WithAdditionalAnnotations(Simplifier.Annotation);
+
+            resultNode = SimplificationHelpers.CopyAnnotations(from: node, to: resultNode);
+
+            return resultNode;
+        }
     }
 }

src/Workspaces/CSharp/Portable/Simplification/Reducers/CSharpCastReducer.cs

@@ -31,24 +31,7 @@ private static ExpressionSyntax SimplifyCast(CastExpressionSyntax node, Semantic
                 return node;
             }
 
-            var leadingTrivia = node.OpenParenToken.LeadingTrivia
-                .Concat(node.OpenParenToken.TrailingTrivia)
-                .Concat(node.Type.GetLeadingTrivia())
-                .Concat(node.Type.GetTrailingTrivia())
-                .Concat(node.CloseParenToken.LeadingTrivia)
-                .Concat(node.CloseParenToken.TrailingTrivia)
-                .Concat(node.Expression.GetLeadingTrivia())
-                .Where(t => !t.IsElastic());
-
-            var trailingTrivia = node.GetTrailingTrivia().Where(t => !t.IsElastic());
-
-            var resultNode = node.Expression
-                .WithLeadingTrivia(leadingTrivia)
-                .WithTrailingTrivia(trailingTrivia);
-
-            resultNode = SimplificationHelpers.CopyAnnotations(from: node, to: resultNode);
-
-            return resultNode;
+            return node.Uncast();
         }
     }
 }

src/Workspaces/VisualBasic/Portable/Extensions/CallStatementSyntaxExtensions.vb

 ' Copyright (c) Microsoft.  All Rights Reserved.  Licensed under the Apache License, Version 2.0.  See License.txt in the project root for license information.
 
 Imports System.Runtime.CompilerServices
-Imports Microsoft.CodeAnalysis.Text
-Imports Microsoft.CodeAnalysis.VisualBasic
-Imports Microsoft.CodeAnalysis.VisualBasic.Symbols
 Imports Microsoft.CodeAnalysis.VisualBasic.Syntax
 
 Namespace Microsoft.CodeAnalysis.VisualBasic.Extensions

src/Workspaces/VisualBasic/Portable/Extensions/CastExpressionSyntaxExtensions.vb

+' Copyright (c) Microsoft.  All Rights Reserved.  Licensed under the Apache License, Version 2.0.  See License.txt in the project root for license information.
+
+Imports System.Runtime.CompilerServices
+Imports Microsoft.CodeAnalysis.Simplification
+Imports Microsoft.CodeAnalysis.VisualBasic.Syntax
+
+Namespace Microsoft.CodeAnalysis.VisualBasic.Extensions
+    Friend Module CastExpressionSyntaxExtensions
+        <Extension>
+        Public Function Uncast(cast As CastExpressionSyntax) As ExpressionSyntax
+            Return Uncast(cast, cast.Expression)
+        End Function
+
+        <Extension>
+        Public Function Uncast(cast As PredefinedCastExpressionSyntax) As ExpressionSyntax
+            Return Uncast(cast, cast.Expression)
+        End Function
+
+        Private Function Uncast(castNode As ExpressionSyntax, innerNode As ExpressionSyntax) As ExpressionSyntax
+            Dim resultNode = innerNode.WithTriviaFrom(castNode)
+
+            resultNode = SimplificationHelpers.CopyAnnotations(castNode, resultNode)
+
+            Return resultNode
+
+        End Function
+    End Module
+End Namespace

src/Workspaces/VisualBasic/Portable/Simplification/Reducers/VisualBasicCastReducer.vb

@@ -17,22 +17,6 @@ Namespace Microsoft.CodeAnalysis.VisualBasic.Simplification
             MyBase.New(s_pool)
         End Sub
 
-        Private Overloads Shared Function SimplifyCast(
-            castNode As ExpressionSyntax,
-            innerNode As ExpressionSyntax,
-            optionSet As OptionSet,
-            cancellationToken As CancellationToken
-        ) As ExpressionSyntax
-
-            Dim resultNode = innerNode _
-                .WithLeadingTrivia(castNode.GetLeadingTrivia()) _
-                .WithTrailingTrivia(castNode.GetTrailingTrivia())
-
-            resultNode = SimplificationHelpers.CopyAnnotations(castNode, resultNode)
-
-            Return resultNode
-        End Function
-
         Private Shared ReadOnly s_simplifyCast As Func(Of CastExpressionSyntax, SemanticModel, OptionSet, CancellationToken, SyntaxNode) = AddressOf SimplifyCast
 
         Private Overloads Shared Function SimplifyCast(
@@ -46,7 +30,7 @@ Namespace Microsoft.CodeAnalysis.VisualBasic.Simplification
                 Return node
             End If
 
-            Return SimplifyCast(node, node.Expression, optionSet, cancellationToken)
+            Return node.Uncast()
         End Function
 
         Private Shared ReadOnly s_simplifyPredefinedCast As Func(Of PredefinedCastExpressionSyntax, SemanticModel, OptionSet, CancellationToken, SyntaxNode) = AddressOf SimplifyPredefinedCast
@@ -62,7 +46,7 @@ Namespace Microsoft.CodeAnalysis.VisualBasic.Simplification
                 Return node
             End If
 
-            Return SimplifyCast(node, node.Expression, optionSet, cancellationToken)
+            Return node.Uncast()
         End Function
     End Class
 End Namespace