Move 'use object expression' fixer over to helper base class

Author: CyrusNajmabadi

src/Analyzers/Core/CodeFixes/UseObjectInitializer/AbstractUseObjectInitializerCodeFixProvider.cs

@@ -2,10 +2,7 @@
 // The .NET Foundation licenses this file to you under the MIT license.
 // See the LICENSE file in the project root for more information.
 
-using System;
-using System.Collections.Generic;
 using System.Collections.Immutable;
-using System.Linq;
 using System.Threading;
 using System.Threading.Tasks;
 using Microsoft.CodeAnalysis.CodeActions;
@@ -27,7 +24,7 @@ internal abstract class AbstractUseObjectInitializerCodeFixProvider<
         TMemberAccessExpressionSyntax,
         TAssignmentStatementSyntax,
         TVariableDeclaratorSyntax>
-        : SyntaxEditorBasedCodeFixProvider
+        : ForkingSyntaxEditorBasedCodeFixProvider<TObjectCreationExpressionSyntax>
         where TSyntaxKind : struct
         where TExpressionSyntax : SyntaxNode
         where TStatementSyntax : SyntaxNode
@@ -36,83 +33,46 @@ internal abstract class AbstractUseObjectInitializerCodeFixProvider<
         where TAssignmentStatementSyntax : TStatementSyntax
         where TVariableDeclaratorSyntax : SyntaxNode
     {
-        public override ImmutableArray<string> FixableDiagnosticIds
-            => ImmutableArray.Create(IDEDiagnosticIds.UseObjectInitializerDiagnosticId);
-
-        protected override bool IncludeDiagnosticDuringFixAll(Diagnostic diagnostic)
-            => !diagnostic.Descriptor.ImmutableCustomTags().Contains(WellKnownDiagnosticTags.Unnecessary);
-
-        public override Task RegisterCodeFixesAsync(CodeFixContext context)
+        protected AbstractUseObjectInitializerCodeFixProvider()
+            : base(AnalyzersResources.Object_initialization_can_be_simplified,
+                   nameof(AnalyzersResources.Object_initialization_can_be_simplified))
         {
-            RegisterCodeFix(context, AnalyzersResources.Object_initialization_can_be_simplified, nameof(AnalyzersResources.Object_initialization_can_be_simplified));
-            return Task.CompletedTask;
         }
 
-        protected override async Task FixAllAsync(
-            Document document, ImmutableArray<Diagnostic> diagnostics,
-            SyntaxEditor editor, CodeActionOptionsProvider fallbackOptions, CancellationToken cancellationToken)
-        {
-            // Fix-All for this feature is somewhat complicated.  As Object-Initializers 
-            // could be arbitrarily nested, we have to make sure that any edits we make
-            // to one Object-Initializer are seen by any higher ones.  In order to do this
-            // we actually process each object-creation-node, one at a time, rewriting
-            // the tree for each node.  In order to do this effectively, we use the '.TrackNodes'
-            // feature to keep track of all the object creation nodes as we make edits to
-            // the tree.  If we didn't do this, then we wouldn't be able to find the 
-            // second object-creation-node after we make the edit for the first one.
-            var syntaxFacts = document.GetLanguageService<ISyntaxFactsService>();
-
-            var originalRoot = editor.OriginalRoot;
-            var originalObjectCreationNodes = new Stack<TObjectCreationExpressionSyntax>();
-            foreach (var diagnostic in diagnostics)
-            {
-                var objectCreation = (TObjectCreationExpressionSyntax)originalRoot.FindNode(
-                    diagnostic.AdditionalLocations[0].SourceSpan, getInnermostNodeForTie: true);
-                originalObjectCreationNodes.Push(objectCreation);
-            }
+        protected abstract TStatementSyntax GetNewStatement(
+            TStatementSyntax statement, TObjectCreationExpressionSyntax objectCreation,
+            ImmutableArray<Match<TExpressionSyntax, TStatementSyntax, TMemberAccessExpressionSyntax, TAssignmentStatementSyntax>> matches);
 
-            // We're going to be continually editing this tree.  Track all the nodes we
-            // care about so we can find them across each edit.
-            document = document.WithSyntaxRoot(originalRoot.TrackNodes(originalObjectCreationNodes));
+        public override ImmutableArray<string> FixableDiagnosticIds
+            => ImmutableArray.Create(IDEDiagnosticIds.UseObjectInitializerDiagnosticId);
 
+        protected override async Task FixAsync(
+            Document document,
+            SyntaxEditor editor,
+            CodeActionOptionsProvider fallbackOptions,
+            TObjectCreationExpressionSyntax objectCreation,
+            ImmutableDictionary<string, string?> properties,
+            CancellationToken cancellationToken)
+        {
+            var syntaxFacts = document.GetRequiredLanguageService<ISyntaxFactsService>();
             var semanticModel = await document.GetSemanticModelAsync(cancellationToken).ConfigureAwait(false);
             var currentRoot = await document.GetRequiredSyntaxRootAsync(cancellationToken).ConfigureAwait(false);
 
-            while (originalObjectCreationNodes.Count > 0)
-            {
-                var originalObjectCreation = originalObjectCreationNodes.Pop();
-                var objectCreation = currentRoot.GetCurrentNodes(originalObjectCreation).Single();
-
-                var matches = UseNamedMemberInitializerAnalyzer<TExpressionSyntax, TStatementSyntax, TObjectCreationExpressionSyntax, TMemberAccessExpressionSyntax, TAssignmentStatementSyntax, TVariableDeclaratorSyntax>.Analyze(
-                    semanticModel, syntaxFacts, objectCreation, cancellationToken);
-
-                if (matches.IsDefaultOrEmpty)
-                    continue;
-
-                var statement = objectCreation.FirstAncestorOrSelf<TStatementSyntax>();
-                Contract.ThrowIfNull(statement);
+            var matches = UseNamedMemberInitializerAnalyzer<TExpressionSyntax, TStatementSyntax, TObjectCreationExpressionSyntax, TMemberAccessExpressionSyntax, TAssignmentStatementSyntax, TVariableDeclaratorSyntax>.Analyze(
+                semanticModel, syntaxFacts, objectCreation, cancellationToken);
 
-                var newStatement = GetNewStatement(statement, objectCreation, matches)
-                    .WithAdditionalAnnotations(Formatter.Annotation);
+            if (matches.IsDefaultOrEmpty)
+                return;
 
-                var subEditor = new SyntaxEditor(currentRoot, document.Project.Solution.Services);
+            var statement = objectCreation.FirstAncestorOrSelf<TStatementSyntax>();
+            Contract.ThrowIfNull(statement);
 
-                subEditor.ReplaceNode(statement, newStatement);
-                foreach (var match in matches)
-                {
-                    subEditor.RemoveNode(match.Statement, SyntaxRemoveOptions.KeepUnbalancedDirectives);
-                }
+            var newStatement = GetNewStatement(statement, objectCreation, matches)
+                .WithAdditionalAnnotations(Formatter.Annotation);
 
-                document = document.WithSyntaxRoot(subEditor.GetChangedRoot());
-                semanticModel = await document.GetSemanticModelAsync(cancellationToken).ConfigureAwait(false);
-                currentRoot = await document.GetRequiredSyntaxRootAsync(cancellationToken).ConfigureAwait(false);
-            }
-
-            editor.ReplaceNode(editor.OriginalRoot, currentRoot);
+            editor.ReplaceNode(statement, newStatement);
+            foreach (var match in matches)
+                editor.RemoveNode(match.Statement, SyntaxRemoveOptions.KeepUnbalancedDirectives);
         }
-
-        protected abstract TStatementSyntax GetNewStatement(
-            TStatementSyntax statement, TObjectCreationExpressionSyntax objectCreation,
-            ImmutableArray<Match<TExpressionSyntax, TStatementSyntax, TMemberAccessExpressionSyntax, TAssignmentStatementSyntax>> matches);
     }
 }