Merge pull request #9378 from CyrusNajmabadi/flattenGenerateVariableSmartTag

Improve the Generate-Variable code-actions menu experience.

Fixes #5139

src/EditorFeatures/CSharpTest/Diagnostics/GenerateVariable/GenerateVariableTests.cs

@@ -3,6 +3,7 @@
 using System;
 using System.Collections.Generic;
 using System.Threading.Tasks;
+using Microsoft.CodeAnalysis.CodeActions;
 using Microsoft.CodeAnalysis.CodeFixes;
 using Microsoft.CodeAnalysis.CSharp.CodeFixes.GenerateVariable;
 using Microsoft.CodeAnalysis.CSharp.CodeStyle;
@@ -21,6 +22,11 @@ public class GenerateVariableTests : AbstractCSharpDiagnosticProviderBasedUserDi
                 null, new GenerateVariableCodeFixProvider());
         }
 
+        protected override IList<CodeAction> MassageActions(IList<CodeAction> actions)
+        {
+            return FlattenActions(actions);
+        }
+
         [Fact, Trait(Traits.Feature, Traits.Features.CodeActionsGenerateVariable)]
         public async Task TestSimpleLowercaseIdentifier1()
         {

src/EditorFeatures/VisualBasicTest/Diagnostics/GenerateVariable/GenerateVariableTests.vb

@@ -3,6 +3,7 @@
 Option Strict Off
 
 Imports System.Threading.Tasks
+Imports Microsoft.CodeAnalysis.CodeActions
 Imports Microsoft.CodeAnalysis.CodeFixes
 Imports Microsoft.CodeAnalysis.Diagnostics
 Imports Microsoft.CodeAnalysis.VisualBasic.CodeFixes.GenerateVariable
@@ -15,6 +16,10 @@ Namespace Microsoft.CodeAnalysis.Editor.VisualBasic.UnitTests.Diagnostics.Genera
             Return New Tuple(Of DiagnosticAnalyzer, CodeFixProvider)(Nothing, New GenerateVariableCodeFixProvider())
         End Function
 
+        Protected Overrides Function MassageActions(actions As IList(Of CodeAction)) As IList(Of CodeAction)
+            Return FlattenActions(actions)
+        End Function
+
         <Fact, Trait(Traits.Feature, Traits.Features.CodeActionsGenerateVariable)>
         Public Async Function TestGenerateSimpleProperty() As Threading.Tasks.Task
             Await TestAsync(

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

@@ -880,6 +880,15 @@ internal class FeaturesResources {
             }
         }
         
+        /// <summary>
+        ///   Looks up a localized string similar to Generate variable.
+        /// </summary>
+        internal static string Generate_variable {
+            get {
+                return ResourceManager.GetString("Generate_variable", resourceCulture);
+            }
+        }
+        
         /// <summary>
         ///   Looks up a localized string similar to Generate abstract method &apos;{0}&apos; in &apos;{1}&apos;.
         /// </summary>

src/Features/Core/Portable/FeaturesResources.resx

@@ -885,4 +885,7 @@ Do you want to continue?</value>
   <data name="Make_method_synchronous" xml:space="preserve">
     <value>Make method synchronous.</value>
   </data>
+  <data name="Generate_variable" xml:space="preserve">
+    <value>Generate variable</value>
+  </data>
 </root>
\ No newline at end of file

src/Features/Core/Portable/GenerateMember/GenerateVariable/AbstractGenerateVariableService.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.Collections.Immutable;
 using System.Linq;
 using System.Threading;
 using System.Threading.Tasks;
@@ -45,7 +46,7 @@ protected AbstractGenerateVariableService()
                     return SpecializedCollections.EmptyEnumerable<CodeAction>();
                 }
 
-                var result = new List<CodeAction>();
+                var actions = new List<CodeAction>();
 
                 var canGenerateMember = CodeGenerator.CanAdd(document.Project.Solution, state.TypeToGenerateIn, cancellationToken);
 
@@ -56,24 +57,32 @@ protected AbstractGenerateVariableService()
                 {
                     if (canGenerateMember)
                     {
-                        AddPropertyCodeActions(result, document, state);
-                        AddFieldCodeActions(result, document, state);
+                        AddPropertyCodeActions(actions, document, state);
+                        AddFieldCodeActions(actions, document, state);
                     }
 
-                    AddLocalCodeActions(result, document, state);
+                    AddLocalCodeActions(actions, document, state);
                 }
                 else
                 {
                     if (canGenerateMember)
                     {
-                        AddFieldCodeActions(result, document, state);
-                        AddPropertyCodeActions(result, document, state);
+                        AddFieldCodeActions(actions, document, state);
+                        AddPropertyCodeActions(actions, document, state);
                     }
 
-                    AddLocalCodeActions(result, document, state);
+                    AddLocalCodeActions(actions, document, state);
                 }
 
-                return result;
+                if (actions.Count > 1)
+                {
+                    // Wrap the generate variable actions into a single top level suggestion
+                    // so as to not clutter the list.
+                    return SpecializedCollections.SingletonEnumerable(
+                        new MyCodeAction(FeaturesResources.Generate_variable, actions.AsImmutable()));
+                }
+
+                return actions;
             }
         }
 
@@ -136,5 +145,13 @@ private void AddLocalCodeActions(List<CodeAction> result, Document document, Sta
                 result.Add(new GenerateLocalCodeAction((TService)this, document, state));
             }
         }
+
+        private class MyCodeAction : CodeAction.SimpleCodeAction
+        {
+            public MyCodeAction(string title, ImmutableArray<CodeAction> nestedActions)
+                : base(title, nestedActions)
+            {
+            }
+        }
     }
 }