Merge pull request #31648 from rik-smeets/add-expression-body-refactoring-local-functions

Include local functions in 'Use expression body' refactoring

src/EditorFeatures/CSharpTest/UseExpressionBody/Analyzer/UseExpressionBodyForLocalFunctionsAnalyzerTests.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.Collections.Generic;
+using System.Threading.Tasks;
+using Microsoft.CodeAnalysis.CodeFixes;
+using Microsoft.CodeAnalysis.CSharp.CodeStyle;
+using Microsoft.CodeAnalysis.CSharp.UseExpressionBody;
+using Microsoft.CodeAnalysis.Diagnostics;
+using Microsoft.CodeAnalysis.Editor.CSharp.UnitTests.Diagnostics;
+using Microsoft.CodeAnalysis.Options;
+using Microsoft.CodeAnalysis.Test.Utilities;
+using Roslyn.Test.Utilities;
+using Xunit;
+
+namespace Microsoft.CodeAnalysis.Editor.CSharp.UnitTests.UseExpressionBody
+{
+    public class UseExpressionBodyForLocalFunctionsAnalyzerTests : AbstractCSharpDiagnosticProviderBasedUserDiagnosticTest
+    {
+        internal override (DiagnosticAnalyzer, CodeFixProvider) CreateDiagnosticProviderAndFixer(Workspace workspace)
+            => (new UseExpressionBodyDiagnosticAnalyzer(), new UseExpressionBodyCodeFixProvider());
+
+        private IDictionary<OptionKey, object> UseExpressionBody =>
+            Option(CSharpCodeStyleOptions.PreferExpressionBodiedLocalFunctions, CSharpCodeStyleOptions.WhenPossibleWithSilentEnforcement);
+
+        private IDictionary<OptionKey, object> UseExpressionBodyWhenOnSingleLine =>
+            Option(CSharpCodeStyleOptions.PreferExpressionBodiedLocalFunctions, CSharpCodeStyleOptions.WhenOnSingleLineWithSilentEnforcement);
+
+        private IDictionary<OptionKey, object> UseBlockBody =>
+            Option(CSharpCodeStyleOptions.PreferExpressionBodiedLocalFunctions, CSharpCodeStyleOptions.NeverWithSilentEnforcement);
+
+        [Fact, Trait(Traits.Feature, Traits.Features.CodeActionsUseExpressionBody)]
+        public async Task TestUseExpressionBody1()
+        {
+            await TestInRegularAndScriptAsync(
+@"class C
+{
+    void Goo()
+    {
+        void Bar()
+        {
+            [|Test|]();
+        }
+    }
+}",
+@"class C
+{
+    void Goo()
+    {
+        void Bar() => Test();
+    }
+}", options: UseExpressionBody);
+        }
+
+        [Fact, Trait(Traits.Feature, Traits.Features.CodeActionsUseExpressionBody)]
+        public async Task TestUseExpressionBody2()
+        {
+            await TestInRegularAndScriptAsync(
+@"class C
+{
+    void Goo()
+    {
+        int Bar()
+        {
+            return [|Test|]();
+        }
+    }
+}",
+@"class C
+{
+    void Goo()
+    {
+        int Bar() => Test();
+    }
+}", options: UseExpressionBody);
+        }
+
+        [Fact, Trait(Traits.Feature, Traits.Features.CodeActionsUseExpressionBody)]
+        public async Task TestUseExpressionBody3()
+        {
+            await TestInRegularAndScriptAsync(
+@"class C
+{
+    int Goo()
+    {
+        int Bar()
+        {
+            [|throw|] new NotImplementedException();
+        }
+    }
+}",
+@"class C
+{
+    int Goo()
+    {
+        int Bar() => [|throw|] new NotImplementedException();
+    }
+}", options: UseExpressionBody);
+        }
+
+        [Fact, Trait(Traits.Feature, Traits.Features.CodeActionsUseExpressionBody)]
+        public async Task TestUseExpressionBody4()
+        {
+            await TestInRegularAndScriptAsync(
+@"class C
+{
+    int Goo()
+    {
+        int Bar()
+        {
+            [|throw|] new NotImplementedException(); // comment
+        }
+    }
+}",
+@"class C
+{
+    int Goo()
+    {
+        int Bar() => [|throw|] new NotImplementedException(); // comment
+    }
+}", options: UseExpressionBody);
+        }
+
+        [Fact, Trait(Traits.Feature, Traits.Features.CodeActionsUseExpressionBody)]
+        public async Task TestUseExpressionBodyWhenOnSingleLineMissing()
+        {
+            await TestMissingInRegularAndScriptAsync(
+@"class C
+{
+    int Goo()
+    {
+        int Bar()
+        {
+            [|return|] 1 +
+                2 +
+                3;
+        }
+    }
+}", new TestParameters(options: UseExpressionBodyWhenOnSingleLine));
+        }
+
+        [Fact, Trait(Traits.Feature, Traits.Features.CodeActionsUseExpressionBody)]
+        public async Task TestUseExpressionBodyWhenOnSingleLine()
+        {
+            await TestInRegularAndScriptAsync(
+@"class C
+{
+    int Goo()
+    {
+        int Bar()
+        {
+            [|return|] 1 + 2 + 3;
+        }
+    }
+}",
+@"class C
+{
+    int Goo()
+    {
+        int Bar() => 1 + 2 + 3;
+    }
+}", options: UseExpressionBodyWhenOnSingleLine);
+        }
+
+        [Fact, Trait(Traits.Feature, Traits.Features.CodeActionsUseExpressionBody)]
+        public async Task TestUseBlockBody1()
+        {
+            await TestInRegularAndScriptAsync(
+@"class C
+{
+    void Goo()
+    {
+        void Bar() => [|Test()|];
+    }
+}",
+@"class C
+{
+    void Goo()
+    {
+        void Bar()
+        {
+            Test();
+        }
+    }
+}", options: UseBlockBody);
+        }
+
+        [Fact, Trait(Traits.Feature, Traits.Features.CodeActionsUseExpressionBody)]
+        public async Task TestUseBlockBody2()
+        {
+            await TestInRegularAndScriptAsync(
+@"class C
+{
+    int Goo()
+    {
+        int Bar() => [|Test|]();
+    }
+}",
+@"class C
+{
+    int Goo()
+    {
+        int Bar()
+        {
+            return Test();
+        }
+    }
+}", options: UseBlockBody);
+        }
+
+        [Fact, Trait(Traits.Feature, Traits.Features.CodeActionsUseExpressionBody)]
+        public async Task TestUseBlockBody3()
+        {
+            await TestInRegularAndScriptAsync(
+@"class C
+{
+    int Goo()
+    {
+        int Bar() => [|throw|] new NotImplementedException();
+    }
+}",
+@"class C
+{
+    int Goo()
+    {
+        int Bar()
+        {
+            throw new NotImplementedException();
+        }
+    }
+}", options: UseBlockBody);
+        }
+
+        [Fact, Trait(Traits.Feature, Traits.Features.CodeActionsUseExpressionBody)]
+        public async Task TestUseBlockBody4()
+        {
+            await TestInRegularAndScriptAsync(
+@"class C
+{
+    int Goo()
+    {
+        int Bar() => [|throw|] new NotImplementedException(); // comment
+    }
+}",
+@"class C
+{
+    int Goo()
+    {
+        int Bar()
+        {
+            throw new NotImplementedException(); // comment
+        }
+    }
+}", options: UseBlockBody);
+        }
+
+        [Fact, Trait(Traits.Feature, Traits.Features.CodeActionsUseExpressionBody)]
+        public async Task TestComments1()
+        {
+            await TestInRegularAndScriptAsync(
+@"class C
+{
+    void Goo()
+    {
+        void Bar()
+        {
+            // Comment
+            [|Test|]();
+        }
+    }
+}",
+@"class C
+{
+    void Goo()
+    {
+        void Bar() =>
+            // Comment
+            Test();
+    }
+}", options: UseExpressionBody);
+        }
+
+        [Fact, Trait(Traits.Feature, Traits.Features.CodeActionsUseExpressionBody)]
+        public async Task TestComments2()
+        {
+            await TestInRegularAndScriptAsync(
+@"class C
+{
+    int Goo()
+    {
+        int Bar()
+        {
+            // Comment
+            return [|Test|]();
+        }
+    }
+}",
+@"class C
+{
+    int Goo()
+    {
+        int Bar() =>
+            // Comment
+            Test();
+    }
+}", options: UseExpressionBody);
+        }
+
+        [Fact, Trait(Traits.Feature, Traits.Features.CodeActionsUseExpressionBody)]
+        public async Task TestComments3()
+        {
+            await TestInRegularAndScriptAsync(
+@"class C
+{
+    void Goo()
+    {
+        void Bar()
+        {
+            // Comment
+            throw [|Test|]();
+        }
+    }
+}",
+@"class C
+{
+    void Goo()
+    {
+        void Bar() =>
+            // Comment
+            throw Test();
+    }
+}", options: UseExpressionBody);
+        }
+
+        [Fact, Trait(Traits.Feature, Traits.Features.CodeActionsUseExpressionBody)]
+        public async Task TestComments4()
+        {
+            await TestInRegularAndScriptAsync(
+@"class C
+{
+    void Goo()
+    {
+        void Bar()
+        {
+            [|Test|](); // Comment
+        }
+    }
+}",
+@"class C
+{
+    void Goo()
+    {
+        void Bar() => Test(); // Comment
+    }
+}", options: UseExpressionBody);
+        }
+
+        [Fact, Trait(Traits.Feature, Traits.Features.CodeActionsUseExpressionBody)]
+        public async Task TestComments5()
+        {
+            await TestInRegularAndScriptAsync(
+@"class C
+{
+    int Goo()
+    {
+        int Bar()
+        {
+            return [|Test|](); // Comment
+        }
+    }
+}",
+@"class C
+{
+    int Goo()
+    {
+        int Bar() => Test(); // Comment
+    }
+}", options: UseExpressionBody);
+        }
+
+        [Fact, Trait(Traits.Feature, Traits.Features.CodeActionsUseExpressionBody)]
+        public async Task TestComments6()
+        {
+            await TestInRegularAndScriptAsync(
+@"class C
+{
+    void Goo()
+    {
+        void Bar()
+        {
+            throw [|Test|](); // Comment
+        }
+    }
+}",
+@"class C
+{
+    void Goo()
+    {
+        void Bar() => throw Test(); // Comment
+    }
+}", options: UseExpressionBody);
+        }
+
+        [Fact, Trait(Traits.Feature, Traits.Features.CodeActionsUseExpressionBody)]
+        public async Task TestDirectives1()
+        {
+            await TestInRegularAndScriptAsync(
+@"
+#define DEBUG
+using System;
+
+class Program
+{
+    void Method()
+    {
+        void Bar()
+        {
+#if DEBUG
+            [|Console|].WriteLine();
+#endif
+        }
+    }
+}",
+@"
+#define DEBUG
+using System;
+
+class Program
+{
+    void Method()
+    {
+        void Bar() =>
+#if DEBUG
+            Console.WriteLine();
+#endif
+
+    }
+}", options: UseExpressionBody);
+        }
+
+        [Fact, Trait(Traits.Feature, Traits.Features.CodeActionsUseExpressionBody)]
+        public async Task TestDirectives2()
+        {
+            await TestInRegularAndScriptAsync(
+@"
+#define DEBUG
+using System;
+
+class Program
+{
+    void Method()
+    {
+        void Bar()
+        {
+#if DEBUG
+            [|Console|].WriteLine(a);
+#else
+            Console.WriteLine(b);
+#endif
+        }
+    }
+}",
+@"
+#define DEBUG
+using System;
+
+class Program
+{
+    void Method()
+    {
+        void Bar() =>
+#if DEBUG
+            Console.WriteLine(a);
+#else
+            Console.WriteLine(b);
+#endif
+
+    }
+}", options: UseExpressionBody);
+        }
+
+        [Fact, Trait(Traits.Feature, Traits.Features.CodeActionsUseExpressionBody)]
+        public async Task TestUseBlockBodyAsync1()
+        {
+            await TestInRegularAndScriptAsync(
+@"using System.Threading.Tasks;
+
+class C
+{
+    async Task Goo()
+    {
+        async Task Bar() [|=>|] await Test();
+    }
+
+    Task Test() { }
+}",
+@"using System.Threading.Tasks;
+
+class C
+{
+    async Task Goo()
+    {
+        async Task Bar()
+        {
+            await Test();
+        }
+    }
+
+    Task Test() { }
+}", options: UseBlockBody);
+        }
+
+        [Fact, Trait(Traits.Feature, Traits.Features.CodeActionsUseExpressionBody)]
+        public async Task TestUseBlockBodyAsync2()
+        {
+            await TestInRegularAndScriptAsync(
+@"using System.Threading.Tasks;
+
+class C
+{
+    async void Goo()
+    {
+        async void Bar() [|=>|] await Test();
+    }
+
+    Task Test() { }
+}",
+@"using System.Threading.Tasks;
+
+class C
+{
+    async void Goo()
+    {
+        async void Bar()
+        {
+            await Test();
+        }
+    }
+
+    Task Test() { }
+}", options: UseBlockBody);
+        }
+
+        [Fact, Trait(Traits.Feature, Traits.Features.CodeActionsUseExpressionBody)]
+        public async Task TestUseBlockBodyAsync3()
+        {
+            await TestInRegularAndScriptAsync(
+@"using System.Threading.Tasks;
+
+class C
+{
+    async ValueTask Goo() 
+    {
+        async ValueTask Test() [|=>|] await Bar();
+    }
+
+    Task Bar() { }
+}",
+@"using System.Threading.Tasks;
+
+class C
+{
+    async ValueTask Goo() 
+    {
+        async ValueTask Test()
+        {
+            await Bar();
+        }
+    }
+
+    Task Bar() { }
+}", options: UseBlockBody);
+        }
+
+        [Fact, Trait(Traits.Feature, Traits.Features.CodeActionsUseExpressionBody)]
+        public async Task TestUseBlockBodyAsync4()
+        {
+            await TestInRegularAndScriptAsync(
+@"using System.Threading.Tasks;
+
+class C
+{
+    async Task<int> Goo()
+    {
+        Task<int> Test() [|=>|] Bar();
+    }
+
+    Task<int> Bar() { }
+}",
+@"using System.Threading.Tasks;
+
+class C
+{
+    async Task<int> Goo()
+    {
+        Task<int> Test()
+        {
+            return Bar();
+        }
+    }
+
+    Task<int> Bar() { }
+}", options: UseBlockBody);
+        }
+
+        [Fact, Trait(Traits.Feature, Traits.Features.CodeActionsUseExpressionBody)]
+        public async Task TestUseBlockBodyAsync5()
+        {
+            await TestInRegularAndScriptAsync(
+@"using System.Threading.Tasks;
+
+class C
+{
+    Task Goo() 
+    {
+        Task Test() [|=>|] Bar();
+    }
+
+    Task Bar() { }
+}",
+@"using System.Threading.Tasks;
+
+class C
+{
+    Task Goo() 
+    {
+        Task Test()
+        {
+            return Bar();
+        }
+    }
+
+    Task Bar() { }
+}", options: UseBlockBody);
+        }
+
+        [Fact, Trait(Traits.Feature, Traits.Features.CodeActionsUseExpressionBody)]
+        public async Task TestUseBlockBodyNestedLocalFunction()
+        {
+            await TestInRegularAndScriptAsync(
+@"class C
+{
+    void Goo()
+    {
+        void Bar()
+        {
+            void Test() => [|NestedTest()|];
+        }
+    }
+}",
+@"class C
+{
+    void Goo()
+    {
+        void Bar()
+        {
+            void Test()
+            {
+                NestedTest();
+            }
+        }
+    }
+}", options: UseBlockBody);
+        }
+
+        [Fact, Trait(Traits.Feature, Traits.Features.CodeActionsUseExpressionBody)]
+        public async Task TestUseExpressionBodyNestedLocalFunction()
+        {
+            await TestInRegularAndScriptAsync(
+@"class C
+{
+    void Goo()
+    {
+        void Bar()
+        {
+            void Test()
+            {
+                [|NestedTest()|];
+            }
+        }
+    }
+}",
+@"class C
+{
+    void Goo()
+    {
+        void Bar()
+        {
+            void Test() => NestedTest();
+        }
+    }
+}", options: UseExpressionBody);
+        }
+    }
+}

src/EditorFeatures/CSharpTest/UseExpressionBody/Refactoring/UseExpressionBodyForLocalFunctionsRefactoringTests.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.Collections.Generic;
+using System.Threading.Tasks;
+using Microsoft.CodeAnalysis.CodeRefactorings;
+using Microsoft.CodeAnalysis.CodeStyle;
+using Microsoft.CodeAnalysis.CSharp.CodeStyle;
+using Microsoft.CodeAnalysis.CSharp.UseExpressionBody;
+using Microsoft.CodeAnalysis.Editor.CSharp.UnitTests.CodeRefactorings;
+using Microsoft.CodeAnalysis.Options;
+using Microsoft.CodeAnalysis.Test.Utilities;
+using Roslyn.Test.Utilities;
+using Xunit;
+
+namespace Microsoft.CodeAnalysis.Editor.CSharp.UnitTests.UseExpressionBody
+{
+    public class UseExpressionBodyForLocalFunctionsRefactoringTests : AbstractCSharpCodeActionTest
+    {
+        protected override CodeRefactoringProvider CreateCodeRefactoringProvider(Workspace workspace, TestParameters parameters)
+            => new UseExpressionBodyCodeRefactoringProvider();
+
+        private IDictionary<OptionKey, object> UseExpressionBody =>
+            Option(CSharpCodeStyleOptions.PreferExpressionBodiedLocalFunctions, CSharpCodeStyleOptions.WhenPossibleWithSilentEnforcement);
+
+        private IDictionary<OptionKey, object> UseExpressionBodyDisabledDiagnostic =>
+            Option(CSharpCodeStyleOptions.PreferExpressionBodiedLocalFunctions, new CodeStyleOption<ExpressionBodyPreference>(ExpressionBodyPreference.WhenPossible, NotificationOption.None));
+
+        private IDictionary<OptionKey, object> UseBlockBody =>
+            Option(CSharpCodeStyleOptions.PreferExpressionBodiedLocalFunctions, CSharpCodeStyleOptions.NeverWithSilentEnforcement);
+
+        private IDictionary<OptionKey, object> UseBlockBodyDisabledDiagnostic =>
+            Option(CSharpCodeStyleOptions.PreferExpressionBodiedLocalFunctions, new CodeStyleOption<ExpressionBodyPreference>(ExpressionBodyPreference.Never, NotificationOption.None));
+
+        [Fact, Trait(Traits.Feature, Traits.Features.CodeActionsUseExpressionBody)]
+        public async Task TestNotOfferedIfUserPrefersExpressionBodiesAndInBlockBody()
+        {
+            await TestMissingAsync(
+@"class C
+{
+    void Goo()
+    {
+        void Bar() 
+        {
+            [||]Test();
+        }
+    }
+}", parameters: new TestParameters(options: UseExpressionBody));
+        }
+
+        [Fact, Trait(Traits.Feature, Traits.Features.CodeActionsUseExpressionBody)]
+        public async Task TestOfferedIfUserPrefersExpressionBodiesWithoutDiagnosticAndInBlockBody()
+        {
+            await TestInRegularAndScript1Async(
+@"class C
+{
+    void Goo()
+    {
+        void Bar() 
+        {
+            [||]Test();
+        }
+    }
+}",
+@"class C
+{
+    void Goo()
+    {
+        void Bar() => Test();
+    }
+}", parameters: new TestParameters(options: UseExpressionBodyDisabledDiagnostic));
+        }
+
+        [Fact, Trait(Traits.Feature, Traits.Features.CodeActionsUseExpressionBody)]
+        public async Task TestOfferedIfUserPrefersBlockBodiesAndInBlockBody()
+        {
+            await TestInRegularAndScript1Async(
+@"class C
+{
+    void Goo()
+    {
+        void Bar() 
+        {
+            [||]Test();
+        }
+    }
+}",
+@"class C
+{
+    void Goo()
+    {
+        void Bar() => Test();
+    }
+}", parameters: new TestParameters(options: UseBlockBody));
+        }
+
+        [Fact, Trait(Traits.Feature, Traits.Features.CodeActionsUseExpressionBody)]
+        public async Task TestNotOfferedIfUserPrefersBlockBodiesAndInExpressionBody()
+        {
+            await TestMissingAsync(
+@"class C
+{
+    void Goo()
+    {
+        void Bar() => [||]Test();
+    }
+}", parameters: new TestParameters(options: UseBlockBody));
+        }
+
+        [Fact, Trait(Traits.Feature, Traits.Features.CodeActionsUseExpressionBody)]
+        public async Task TestOfferedIfUserPrefersBlockBodiesWithoutDiagnosticAndInExpressionBody()
+        {
+            await TestInRegularAndScript1Async(
+@"class C
+{
+    void Goo()
+    {
+        void Bar() => [||]Test();
+    }
+}",
+@"class C
+{
+    void Goo()
+    {
+        void Bar()
+        {
+            Test();
+        }
+    }
+}", parameters: new TestParameters(options: UseBlockBodyDisabledDiagnostic));
+        }
+
+        [Fact, Trait(Traits.Feature, Traits.Features.CodeActionsUseExpressionBody)]
+        public async Task TestOfferedIfUserPrefersExpressionBodiesAndInExpressionBody()
+        {
+            await TestInRegularAndScript1Async(
+@"class C
+{
+    void Goo()
+    {
+        void Bar() => [||]Test();
+    }
+}",
+@"class C
+{
+    void Goo()
+    {
+        void Bar()
+        {
+            Test();
+        }
+    }
+}", parameters: new TestParameters(options: UseExpressionBody));
+        }
+    }
+}

src/Features/CSharp/Portable/CodeCleanup/CSharpCodeCleanupService.cs

@@ -84,7 +84,8 @@ internal class CSharpCodeCleanupService : ICodeCleanupService
                                        IDEDiagnosticIds.UseExpressionBodyForOperatorsDiagnosticId,
                                        IDEDiagnosticIds.UseExpressionBodyForPropertiesDiagnosticId,
                                        IDEDiagnosticIds.UseExpressionBodyForIndexersDiagnosticId,
-                                       IDEDiagnosticIds.UseExpressionBodyForAccessorsDiagnosticId)),
+                                       IDEDiagnosticIds.UseExpressionBodyForAccessorsDiagnosticId,
+                                       IDEDiagnosticIds.UseExpressionBodyForLocalFunctionsDiagnosticId)),
 
                 (CSharpFeaturesResources.Apply_inline_out_variable_preferences,
                  CodeCleanupOptions.ApplyInlineOutVariablePreferences,

src/Features/CSharp/Portable/UseExpressionBody/Helpers/UseExpressionBodyForLocalFunctionHelper.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.Collections.Immutable;
+using Microsoft.CodeAnalysis.CSharp.CodeStyle;
+using Microsoft.CodeAnalysis.CSharp.Extensions;
+using Microsoft.CodeAnalysis.CSharp.Syntax;
+using Microsoft.CodeAnalysis.Diagnostics;
+
+namespace Microsoft.CodeAnalysis.CSharp.UseExpressionBody
+{
+    internal class UseExpressionBodyForLocalFunctionHelper : 
+        UseExpressionBodyHelper<LocalFunctionStatementSyntax>
+    {
+        public static readonly UseExpressionBodyForLocalFunctionHelper Instance = new UseExpressionBodyForLocalFunctionHelper();
+
+        private UseExpressionBodyForLocalFunctionHelper()
+            : base(IDEDiagnosticIds.UseExpressionBodyForLocalFunctionsDiagnosticId,
+                   new LocalizableResourceString(nameof(FeaturesResources.Use_expression_body_for_local_functions), FeaturesResources.ResourceManager, typeof(FeaturesResources)),
+                   new LocalizableResourceString(nameof(FeaturesResources.Use_block_body_for_local_functions), FeaturesResources.ResourceManager, typeof(FeaturesResources)),
+                   CSharpCodeStyleOptions.PreferExpressionBodiedLocalFunctions,
+                   ImmutableArray.Create(SyntaxKind.LocalFunctionStatement))
+        {
+        }
+
+        protected override BlockSyntax GetBody(LocalFunctionStatementSyntax statement)
+            => statement.Body;
+
+        protected override ArrowExpressionClauseSyntax GetExpressionBody(LocalFunctionStatementSyntax statement)
+            => statement.ExpressionBody;
+
+        protected override SyntaxToken GetSemicolonToken(LocalFunctionStatementSyntax statement)
+            => statement.SemicolonToken;
+
+        protected override LocalFunctionStatementSyntax WithSemicolonToken(LocalFunctionStatementSyntax statement, SyntaxToken token)
+            => statement.WithSemicolonToken(token);
+
+        protected override LocalFunctionStatementSyntax WithExpressionBody(LocalFunctionStatementSyntax statement, ArrowExpressionClauseSyntax expressionBody)
+            => statement.WithExpressionBody(expressionBody);
+
+        protected override LocalFunctionStatementSyntax WithBody(LocalFunctionStatementSyntax statement, BlockSyntax body)
+            => statement.WithBody(body);
+
+        protected override bool CreateReturnStatementForExpression(
+            SemanticModel semanticModel, LocalFunctionStatementSyntax statement)
+        {
+            if (statement.Modifiers.Any(SyntaxKind.AsyncKeyword))
+            {
+                // if it's 'async TaskLike' (where TaskLike is non-generic) we do *not* want to
+                // create a return statement.  This is just the 'async' version of a 'void' local function.
+                var symbol = semanticModel.GetDeclaredSymbol(statement);
+                return symbol is IMethodSymbol methodSymbol &&
+                    methodSymbol.ReturnType is INamedTypeSymbol namedType &&
+                    namedType.Arity != 0;
+            }
+
+            return !statement.ReturnType.IsVoid();
+        }
+    }
+}

src/Features/CSharp/Portable/UseExpressionBody/Helpers/UseExpressionBodyHelper.cs

@@ -33,6 +33,7 @@ internal abstract class UseExpressionBodyHelper
                 UseExpressionBodyForMethodsHelper.Instance,
                 UseExpressionBodyForOperatorsHelper.Instance,
                 UseExpressionBodyForPropertiesHelper.Instance,
-                UseExpressionBodyForAccessorsHelper.Instance);
+                UseExpressionBodyForAccessorsHelper.Instance,
+                UseExpressionBodyForLocalFunctionHelper.Instance);
     }
 }

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

@@ -99,6 +99,9 @@ internal static class IDEDiagnosticIds
         public const string ValueAssignedIsUnusedDiagnosticId = "IDE0059";
         public const string UnusedParameterDiagnosticId = "IDE0060";
 
+        // Conceptually belongs with IDE0021-IDE0027 & IDE0053, but is here because it was added later
+        public const string UseExpressionBodyForLocalFunctionsDiagnosticId = "IDE0061";
+
         // Analyzer error Ids
         public const string AnalyzerChangedId = "IDE1001";
         public const string AnalyzerDependencyConflictId = "IDE1002";

src/Features/Core/Portable/FeaturesResources.Designer.cs

@@ -4059,6 +4059,15 @@ internal class FeaturesResources {
             }
         }
         
+        /// <summary>
+        ///   Looks up a localized string similar to Use block body for local functions.
+        /// </summary>
+        internal static string Use_block_body_for_local_functions {
+            get {
+                return ResourceManager.GetString("Use_block_body_for_local_functions", resourceCulture);
+            }
+        }
+        
         /// <summary>
         ///   Looks up a localized string similar to Use block body for methods.
         /// </summary>
@@ -4167,6 +4176,15 @@ internal class FeaturesResources {
             }
         }
         
+        /// <summary>
+        ///   Looks up a localized string similar to Use expression body for local functions.
+        /// </summary>
+        internal static string Use_expression_body_for_local_functions {
+            get {
+                return ResourceManager.GetString("Use_expression_body_for_local_functions", resourceCulture);
+            }
+        }
+        
         /// <summary>
         ///   Looks up a localized string similar to Use expression body for methods.
         /// </summary>

src/Features/Core/Portable/FeaturesResources.resx

@@ -1595,4 +1595,10 @@ This version used in: {2}</value>
   <data name="Remove_unused_parameter_0_its_initial_value_is_never_used" xml:space="preserve">
     <value>Remove unused parameter '{0}', its initial value is never used</value>
   </data>
+  <data name="Use_block_body_for_local_functions" xml:space="preserve">
+    <value>Use block body for local functions</value>
+  </data>
+  <data name="Use_expression_body_for_local_functions" xml:space="preserve">
+    <value>Use expression body for local functions</value>
+  </data>
 </root>
\ No newline at end of file

src/Features/Core/Portable/xlf/FeaturesResources.cs.xlf

@@ -292,6 +292,11 @@
         <target state="new">Use block body for lambda expressions</target>
         <note />
       </trans-unit>
+      <trans-unit id="Use_block_body_for_local_functions">
+        <source>Use block body for local functions</source>
+        <target state="new">Use block body for local functions</target>
+        <note />
+      </trans-unit>
       <trans-unit id="Use_compound_assignment">
         <source>Use compound assignment</source>
         <target state="new">Use compound assignment</target>
@@ -312,6 +317,11 @@
         <target state="new">Use expression body for lambda expressions</target>
         <note />
       </trans-unit>
+      <trans-unit id="Use_expression_body_for_local_functions">
+        <source>Use expression body for local functions</source>
+        <target state="new">Use expression body for local functions</target>
+        <note />
+      </trans-unit>
       <trans-unit id="Use_index_operator">
         <source>Use index operator</source>
         <target state="new">Use index operator</target>

src/Features/Core/Portable/xlf/FeaturesResources.de.xlf

@@ -292,6 +292,11 @@
         <target state="new">Use block body for lambda expressions</target>
         <note />
       </trans-unit>
+      <trans-unit id="Use_block_body_for_local_functions">
+        <source>Use block body for local functions</source>
+        <target state="new">Use block body for local functions</target>
+        <note />
+      </trans-unit>
       <trans-unit id="Use_compound_assignment">
         <source>Use compound assignment</source>
         <target state="new">Use compound assignment</target>
@@ -312,6 +317,11 @@
         <target state="new">Use expression body for lambda expressions</target>
         <note />
       </trans-unit>
+      <trans-unit id="Use_expression_body_for_local_functions">
+        <source>Use expression body for local functions</source>
+        <target state="new">Use expression body for local functions</target>
+        <note />
+      </trans-unit>
       <trans-unit id="Use_index_operator">
         <source>Use index operator</source>
         <target state="new">Use index operator</target>

src/Features/Core/Portable/xlf/FeaturesResources.es.xlf

@@ -292,6 +292,11 @@
         <target state="new">Use block body for lambda expressions</target>
         <note />
       </trans-unit>
+      <trans-unit id="Use_block_body_for_local_functions">
+        <source>Use block body for local functions</source>
+        <target state="new">Use block body for local functions</target>
+        <note />
+      </trans-unit>
       <trans-unit id="Use_compound_assignment">
         <source>Use compound assignment</source>
         <target state="new">Use compound assignment</target>
@@ -312,6 +317,11 @@
         <target state="new">Use expression body for lambda expressions</target>
         <note />
       </trans-unit>
+      <trans-unit id="Use_expression_body_for_local_functions">
+        <source>Use expression body for local functions</source>
+        <target state="new">Use expression body for local functions</target>
+        <note />
+      </trans-unit>
       <trans-unit id="Use_index_operator">
         <source>Use index operator</source>
         <target state="new">Use index operator</target>

src/Features/Core/Portable/xlf/FeaturesResources.fr.xlf

@@ -292,6 +292,11 @@
         <target state="new">Use block body for lambda expressions</target>
         <note />
       </trans-unit>
+      <trans-unit id="Use_block_body_for_local_functions">
+        <source>Use block body for local functions</source>
+        <target state="new">Use block body for local functions</target>
+        <note />
+      </trans-unit>
       <trans-unit id="Use_compound_assignment">
         <source>Use compound assignment</source>
         <target state="new">Use compound assignment</target>
@@ -312,6 +317,11 @@
         <target state="new">Use expression body for lambda expressions</target>
         <note />
       </trans-unit>
+      <trans-unit id="Use_expression_body_for_local_functions">
+        <source>Use expression body for local functions</source>
+        <target state="new">Use expression body for local functions</target>
+        <note />
+      </trans-unit>
       <trans-unit id="Use_index_operator">
         <source>Use index operator</source>
         <target state="new">Use index operator</target>

src/Features/Core/Portable/xlf/FeaturesResources.it.xlf

@@ -292,6 +292,11 @@
         <target state="new">Use block body for lambda expressions</target>
         <note />
       </trans-unit>
+      <trans-unit id="Use_block_body_for_local_functions">
+        <source>Use block body for local functions</source>
+        <target state="new">Use block body for local functions</target>
+        <note />
+      </trans-unit>
       <trans-unit id="Use_compound_assignment">
         <source>Use compound assignment</source>
         <target state="new">Use compound assignment</target>
@@ -312,6 +317,11 @@
         <target state="new">Use expression body for lambda expressions</target>
         <note />
       </trans-unit>
+      <trans-unit id="Use_expression_body_for_local_functions">
+        <source>Use expression body for local functions</source>
+        <target state="new">Use expression body for local functions</target>
+        <note />
+      </trans-unit>
       <trans-unit id="Use_index_operator">
         <source>Use index operator</source>
         <target state="new">Use index operator</target>

src/Features/Core/Portable/xlf/FeaturesResources.ja.xlf

@@ -292,6 +292,11 @@
         <target state="new">Use block body for lambda expressions</target>
         <note />
       </trans-unit>
+      <trans-unit id="Use_block_body_for_local_functions">
+        <source>Use block body for local functions</source>
+        <target state="new">Use block body for local functions</target>
+        <note />
+      </trans-unit>
       <trans-unit id="Use_compound_assignment">
         <source>Use compound assignment</source>
         <target state="new">Use compound assignment</target>
@@ -312,6 +317,11 @@
         <target state="new">Use expression body for lambda expressions</target>
         <note />
       </trans-unit>
+      <trans-unit id="Use_expression_body_for_local_functions">
+        <source>Use expression body for local functions</source>
+        <target state="new">Use expression body for local functions</target>
+        <note />
+      </trans-unit>
       <trans-unit id="Use_index_operator">
         <source>Use index operator</source>
         <target state="new">Use index operator</target>

src/Features/Core/Portable/xlf/FeaturesResources.ko.xlf

@@ -292,6 +292,11 @@
         <target state="new">Use block body for lambda expressions</target>
         <note />
       </trans-unit>
+      <trans-unit id="Use_block_body_for_local_functions">
+        <source>Use block body for local functions</source>
+        <target state="new">Use block body for local functions</target>
+        <note />
+      </trans-unit>
       <trans-unit id="Use_compound_assignment">
         <source>Use compound assignment</source>
         <target state="new">Use compound assignment</target>
@@ -312,6 +317,11 @@
         <target state="new">Use expression body for lambda expressions</target>
         <note />
       </trans-unit>
+      <trans-unit id="Use_expression_body_for_local_functions">
+        <source>Use expression body for local functions</source>
+        <target state="new">Use expression body for local functions</target>
+        <note />
+      </trans-unit>
       <trans-unit id="Use_index_operator">
         <source>Use index operator</source>
         <target state="new">Use index operator</target>

src/Features/Core/Portable/xlf/FeaturesResources.pl.xlf

@@ -292,6 +292,11 @@
         <target state="new">Use block body for lambda expressions</target>
         <note />
       </trans-unit>
+      <trans-unit id="Use_block_body_for_local_functions">
+        <source>Use block body for local functions</source>
+        <target state="new">Use block body for local functions</target>
+        <note />
+      </trans-unit>
       <trans-unit id="Use_compound_assignment">
         <source>Use compound assignment</source>
         <target state="new">Use compound assignment</target>
@@ -312,6 +317,11 @@
         <target state="new">Use expression body for lambda expressions</target>
         <note />
       </trans-unit>
+      <trans-unit id="Use_expression_body_for_local_functions">
+        <source>Use expression body for local functions</source>
+        <target state="new">Use expression body for local functions</target>
+        <note />
+      </trans-unit>
       <trans-unit id="Use_index_operator">
         <source>Use index operator</source>
         <target state="new">Use index operator</target>

src/Features/Core/Portable/xlf/FeaturesResources.pt-BR.xlf

@@ -292,6 +292,11 @@
         <target state="new">Use block body for lambda expressions</target>
         <note />
       </trans-unit>
+      <trans-unit id="Use_block_body_for_local_functions">
+        <source>Use block body for local functions</source>
+        <target state="new">Use block body for local functions</target>
+        <note />
+      </trans-unit>
       <trans-unit id="Use_compound_assignment">
         <source>Use compound assignment</source>
         <target state="new">Use compound assignment</target>
@@ -312,6 +317,11 @@
         <target state="new">Use expression body for lambda expressions</target>
         <note />
       </trans-unit>
+      <trans-unit id="Use_expression_body_for_local_functions">
+        <source>Use expression body for local functions</source>
+        <target state="new">Use expression body for local functions</target>
+        <note />
+      </trans-unit>
       <trans-unit id="Use_index_operator">
         <source>Use index operator</source>
         <target state="new">Use index operator</target>

src/Features/Core/Portable/xlf/FeaturesResources.ru.xlf

@@ -292,6 +292,11 @@
         <target state="new">Use block body for lambda expressions</target>
         <note />
       </trans-unit>
+      <trans-unit id="Use_block_body_for_local_functions">
+        <source>Use block body for local functions</source>
+        <target state="new">Use block body for local functions</target>
+        <note />
+      </trans-unit>
       <trans-unit id="Use_compound_assignment">
         <source>Use compound assignment</source>
         <target state="new">Use compound assignment</target>
@@ -312,6 +317,11 @@
         <target state="new">Use expression body for lambda expressions</target>
         <note />
       </trans-unit>
+      <trans-unit id="Use_expression_body_for_local_functions">
+        <source>Use expression body for local functions</source>
+        <target state="new">Use expression body for local functions</target>
+        <note />
+      </trans-unit>
       <trans-unit id="Use_index_operator">
         <source>Use index operator</source>
         <target state="new">Use index operator</target>

src/Features/Core/Portable/xlf/FeaturesResources.tr.xlf

@@ -292,6 +292,11 @@
         <target state="new">Use block body for lambda expressions</target>
         <note />
       </trans-unit>
+      <trans-unit id="Use_block_body_for_local_functions">
+        <source>Use block body for local functions</source>
+        <target state="new">Use block body for local functions</target>
+        <note />
+      </trans-unit>
       <trans-unit id="Use_compound_assignment">
         <source>Use compound assignment</source>
         <target state="new">Use compound assignment</target>
@@ -312,6 +317,11 @@
         <target state="new">Use expression body for lambda expressions</target>
         <note />
       </trans-unit>
+      <trans-unit id="Use_expression_body_for_local_functions">
+        <source>Use expression body for local functions</source>
+        <target state="new">Use expression body for local functions</target>
+        <note />
+      </trans-unit>
       <trans-unit id="Use_index_operator">
         <source>Use index operator</source>
         <target state="new">Use index operator</target>

src/Features/Core/Portable/xlf/FeaturesResources.zh-Hans.xlf

@@ -292,6 +292,11 @@
         <target state="new">Use block body for lambda expressions</target>
         <note />
       </trans-unit>
+      <trans-unit id="Use_block_body_for_local_functions">
+        <source>Use block body for local functions</source>
+        <target state="new">Use block body for local functions</target>
+        <note />
+      </trans-unit>
       <trans-unit id="Use_compound_assignment">
         <source>Use compound assignment</source>
         <target state="new">Use compound assignment</target>
@@ -312,6 +317,11 @@
         <target state="new">Use expression body for lambda expressions</target>
         <note />
       </trans-unit>
+      <trans-unit id="Use_expression_body_for_local_functions">
+        <source>Use expression body for local functions</source>
+        <target state="new">Use expression body for local functions</target>
+        <note />
+      </trans-unit>
       <trans-unit id="Use_index_operator">
         <source>Use index operator</source>
         <target state="new">Use index operator</target>

src/Features/Core/Portable/xlf/FeaturesResources.zh-Hant.xlf

@@ -292,6 +292,11 @@
         <target state="new">Use block body for lambda expressions</target>
         <note />
       </trans-unit>
+      <trans-unit id="Use_block_body_for_local_functions">
+        <source>Use block body for local functions</source>
+        <target state="new">Use block body for local functions</target>
+        <note />
+      </trans-unit>
       <trans-unit id="Use_compound_assignment">
         <source>Use compound assignment</source>
         <target state="new">Use compound assignment</target>
@@ -312,6 +317,11 @@
         <target state="new">Use expression body for lambda expressions</target>
         <note />
       </trans-unit>
+      <trans-unit id="Use_expression_body_for_local_functions">
+        <source>Use expression body for local functions</source>
+        <target state="new">Use expression body for local functions</target>
+        <note />
+      </trans-unit>
       <trans-unit id="Use_index_operator">
         <source>Use index operator</source>
         <target state="new">Use index operator</target>

src/VisualStudio/CSharp/Impl/Options/Formatting/StyleViewModel.cs

@@ -1006,6 +1006,45 @@ void Method()
 //]
     }
 }
+";
+
+        private const string s_preferExpressionBodyForLocalFunctions = @"
+using System;
+
+//[
+class Customer
+{
+    private int Age;
+
+    public int GetAge() 
+    {
+        return GetAgeLocal();
+        
+        int GetAgeLocal() => this.Age;
+    }
+}
+//]
+";
+
+        private const string s_preferBlockBodyForLocalFunctions = @"
+using System;
+
+//[
+class Customer
+{
+    private int Age;
+
+    public int GetAge()
+    {
+        return GetAgeLocal();
+        
+        int GetAgeLocal()
+        {
+            return this.Age;
+        }
+    }
+}
+//]
 ";
 
         private static readonly string s_preferReadonly = $@"
@@ -1511,6 +1550,13 @@ private void AddExpressionBodyOptions(OptionSet optionSet, string expressionPref
                 enumValues,
                 new[] { s_preferBlockBodyForLambdas, s_preferExpressionBodyForLambdas, s_preferExpressionBodyForLambdas },
                 this, optionSet, expressionPreferencesGroupTitle, expressionBodyPreferences));
+
+            CodeStyleItems.Add(new EnumCodeStyleOptionViewModel<ExpressionBodyPreference>(
+                CSharpCodeStyleOptions.PreferExpressionBodiedLocalFunctions,
+                ServicesVSResources.Use_expression_body_for_local_functions,
+                enumValues,
+                new[] { s_preferBlockBodyForLocalFunctions, s_preferExpressionBodyForLocalFunctions, s_preferExpressionBodyForLocalFunctions },
+                this, optionSet, expressionPreferencesGroupTitle, expressionBodyPreferences));
         }
 
         private void AddUnusedValueOptions(OptionSet optionSet, string expressionPreferencesGroupTitle)

src/VisualStudio/Core/Def/ServicesVSResources.Designer.cs

@@ -2859,6 +2859,15 @@ internal class ServicesVSResources {
             }
         }
         
+        /// <summary>
+        ///   Looks up a localized string similar to Use expression body for local functions.
+        /// </summary>
+        internal static string Use_expression_body_for_local_functions {
+            get {
+                return ResourceManager.GetString("Use_expression_body_for_local_functions", resourceCulture);
+            }
+        }
+        
         /// <summary>
         ///   Looks up a localized string similar to Use expression body for methods.
         /// </summary>

src/VisualStudio/Core/Def/ServicesVSResources.resx

@@ -1120,4 +1120,7 @@ I agree to all of the foregoing:</value>
   <data name="Value_returned_by_invocation_is_implicitly_ignored" xml:space="preserve">
     <value>Value returned by invocation is implicitly ignored</value>
   </data>
+  <data name="Use_expression_body_for_local_functions" xml:space="preserve">
+    <value>Use expression body for local functions</value>
+  </data>
 </root>
\ No newline at end of file

src/VisualStudio/Core/Def/xlf/ServicesVSResources.cs.xlf

@@ -147,6 +147,11 @@
         <target state="new">Use expression body for lambdas</target>
         <note />
       </trans-unit>
+      <trans-unit id="Use_expression_body_for_local_functions">
+        <source>Use expression body for local functions</source>
+        <target state="new">Use expression body for local functions</target>
+        <note />
+      </trans-unit>
       <trans-unit id="Value_assigned_here_is_never_used">
         <source>Value assigned here is never used</source>
         <target state="new">Value assigned here is never used</target>

src/VisualStudio/Core/Def/xlf/ServicesVSResources.de.xlf

@@ -147,6 +147,11 @@
         <target state="new">Use expression body for lambdas</target>
         <note />
       </trans-unit>
+      <trans-unit id="Use_expression_body_for_local_functions">
+        <source>Use expression body for local functions</source>
+        <target state="new">Use expression body for local functions</target>
+        <note />
+      </trans-unit>
       <trans-unit id="Value_assigned_here_is_never_used">
         <source>Value assigned here is never used</source>
         <target state="new">Value assigned here is never used</target>

src/VisualStudio/Core/Def/xlf/ServicesVSResources.es.xlf

@@ -147,6 +147,11 @@
         <target state="new">Use expression body for lambdas</target>
         <note />
       </trans-unit>
+      <trans-unit id="Use_expression_body_for_local_functions">
+        <source>Use expression body for local functions</source>
+        <target state="new">Use expression body for local functions</target>
+        <note />
+      </trans-unit>
       <trans-unit id="Value_assigned_here_is_never_used">
         <source>Value assigned here is never used</source>
         <target state="new">Value assigned here is never used</target>

src/VisualStudio/Core/Def/xlf/ServicesVSResources.fr.xlf

@@ -147,6 +147,11 @@
         <target state="new">Use expression body for lambdas</target>
         <note />
       </trans-unit>
+      <trans-unit id="Use_expression_body_for_local_functions">
+        <source>Use expression body for local functions</source>
+        <target state="new">Use expression body for local functions</target>
+        <note />
+      </trans-unit>
       <trans-unit id="Value_assigned_here_is_never_used">
         <source>Value assigned here is never used</source>
         <target state="new">Value assigned here is never used</target>

src/VisualStudio/Core/Def/xlf/ServicesVSResources.it.xlf

@@ -147,6 +147,11 @@
         <target state="new">Use expression body for lambdas</target>
         <note />
       </trans-unit>
+      <trans-unit id="Use_expression_body_for_local_functions">
+        <source>Use expression body for local functions</source>
+        <target state="new">Use expression body for local functions</target>
+        <note />
+      </trans-unit>
       <trans-unit id="Value_assigned_here_is_never_used">
         <source>Value assigned here is never used</source>
         <target state="new">Value assigned here is never used</target>

src/VisualStudio/Core/Def/xlf/ServicesVSResources.ja.xlf

@@ -147,6 +147,11 @@
         <target state="new">Use expression body for lambdas</target>
         <note />
       </trans-unit>
+      <trans-unit id="Use_expression_body_for_local_functions">
+        <source>Use expression body for local functions</source>
+        <target state="new">Use expression body for local functions</target>
+        <note />
+      </trans-unit>
       <trans-unit id="Value_assigned_here_is_never_used">
         <source>Value assigned here is never used</source>
         <target state="new">Value assigned here is never used</target>

src/VisualStudio/Core/Def/xlf/ServicesVSResources.ko.xlf

@@ -147,6 +147,11 @@
         <target state="new">Use expression body for lambdas</target>
         <note />
       </trans-unit>
+      <trans-unit id="Use_expression_body_for_local_functions">
+        <source>Use expression body for local functions</source>
+        <target state="new">Use expression body for local functions</target>
+        <note />
+      </trans-unit>
       <trans-unit id="Value_assigned_here_is_never_used">
         <source>Value assigned here is never used</source>
         <target state="new">Value assigned here is never used</target>

src/VisualStudio/Core/Def/xlf/ServicesVSResources.pl.xlf

@@ -147,6 +147,11 @@
         <target state="new">Use expression body for lambdas</target>
         <note />
       </trans-unit>
+      <trans-unit id="Use_expression_body_for_local_functions">
+        <source>Use expression body for local functions</source>
+        <target state="new">Use expression body for local functions</target>
+        <note />
+      </trans-unit>
       <trans-unit id="Value_assigned_here_is_never_used">
         <source>Value assigned here is never used</source>
         <target state="new">Value assigned here is never used</target>

src/VisualStudio/Core/Def/xlf/ServicesVSResources.pt-BR.xlf

@@ -147,6 +147,11 @@
         <target state="new">Use expression body for lambdas</target>
         <note />
       </trans-unit>
+      <trans-unit id="Use_expression_body_for_local_functions">
+        <source>Use expression body for local functions</source>
+        <target state="new">Use expression body for local functions</target>
+        <note />
+      </trans-unit>
       <trans-unit id="Value_assigned_here_is_never_used">
         <source>Value assigned here is never used</source>
         <target state="new">Value assigned here is never used</target>

src/VisualStudio/Core/Def/xlf/ServicesVSResources.ru.xlf

@@ -147,6 +147,11 @@
         <target state="new">Use expression body for lambdas</target>
         <note />
       </trans-unit>
+      <trans-unit id="Use_expression_body_for_local_functions">
+        <source>Use expression body for local functions</source>
+        <target state="new">Use expression body for local functions</target>
+        <note />
+      </trans-unit>
       <trans-unit id="Value_assigned_here_is_never_used">
         <source>Value assigned here is never used</source>
         <target state="new">Value assigned here is never used</target>

src/VisualStudio/Core/Def/xlf/ServicesVSResources.tr.xlf

@@ -147,6 +147,11 @@
         <target state="new">Use expression body for lambdas</target>
         <note />
       </trans-unit>
+      <trans-unit id="Use_expression_body_for_local_functions">
+        <source>Use expression body for local functions</source>
+        <target state="new">Use expression body for local functions</target>
+        <note />
+      </trans-unit>
       <trans-unit id="Value_assigned_here_is_never_used">
         <source>Value assigned here is never used</source>
         <target state="new">Value assigned here is never used</target>

src/VisualStudio/Core/Def/xlf/ServicesVSResources.zh-Hans.xlf

@@ -147,6 +147,11 @@
         <target state="new">Use expression body for lambdas</target>
         <note />
       </trans-unit>
+      <trans-unit id="Use_expression_body_for_local_functions">
+        <source>Use expression body for local functions</source>
+        <target state="new">Use expression body for local functions</target>
+        <note />
+      </trans-unit>
       <trans-unit id="Value_assigned_here_is_never_used">
         <source>Value assigned here is never used</source>
         <target state="new">Value assigned here is never used</target>

src/VisualStudio/Core/Def/xlf/ServicesVSResources.zh-Hant.xlf

@@ -147,6 +147,11 @@
         <target state="new">Use expression body for lambdas</target>
         <note />
       </trans-unit>
+      <trans-unit id="Use_expression_body_for_local_functions">
+        <source>Use expression body for local functions</source>
+        <target state="new">Use expression body for local functions</target>
+        <note />
+      </trans-unit>
       <trans-unit id="Value_assigned_here_is_never_used">
         <source>Value assigned here is never used</source>
         <target state="new">Value assigned here is never used</target>

src/VisualStudio/Core/Test/Options/CSharpEditorConfigGeneratorTests.vb

@@ -88,6 +88,7 @@ csharp_style_expression_bodied_accessors = true:silent
 csharp_style_expression_bodied_constructors = false:silent
 csharp_style_expression_bodied_indexers = true:silent
 csharp_style_expression_bodied_lambdas = true:silent
+csharp_style_expression_bodied_local_functions = false:silent
 csharp_style_expression_bodied_methods = false:silent
 csharp_style_expression_bodied_operators = false:silent
 csharp_style_expression_bodied_properties = true:silent
@@ -245,6 +246,7 @@ csharp_style_expression_bodied_accessors = true:silent
 csharp_style_expression_bodied_constructors = false:silent
 csharp_style_expression_bodied_indexers = true:silent
 csharp_style_expression_bodied_lambdas = true:silent
+csharp_style_expression_bodied_local_functions = false:silent
 csharp_style_expression_bodied_methods = false:silent
 csharp_style_expression_bodied_operators = false:silent
 csharp_style_expression_bodied_properties = true:silent

src/Workspaces/CSharp/Portable/CodeStyle/CSharpCodeStyleOptions.cs

@@ -156,6 +156,16 @@ private static Option<T> CreateOption<T>(OptionGroup group, string name, T defau
                     GetExpressionBodyPreferenceEditorConfigString),
                 new RoamingProfileStorageLocation($"TextEditor.CSharp.Specific.{nameof(PreferExpressionBodiedLambdas)}")});
 
+        public static readonly Option<CodeStyleOption<ExpressionBodyPreference>> PreferExpressionBodiedLocalFunctions = CreateOption(
+            CSharpCodeStyleOptionGroups.ExpressionBodiedMembers, nameof(PreferExpressionBodiedLocalFunctions),
+            defaultValue: NeverWithSilentEnforcement,
+            storageLocations: new OptionStorageLocation[] {
+                new EditorConfigStorageLocation<CodeStyleOption<ExpressionBodyPreference>>(
+                    "csharp_style_expression_bodied_local_functions",
+                    s => ParseExpressionBodyPreference(s, NeverWithSilentEnforcement),
+                    GetExpressionBodyPreferenceEditorConfigString),
+                new RoamingProfileStorageLocation($"TextEditor.CSharp.Specific.{nameof(PreferExpressionBodiedLocalFunctions)}")});
+
         public static readonly Option<CodeStyleOption<bool>> PreferBraces = CreateOption(
             CSharpCodeStyleOptionGroups.CodeBlockPreferences, nameof(PreferBraces),
             defaultValue: CodeStyleOptions.TrueWithSilentEnforcement,