1 files changed, 104 insertions, 0 deletions
diff --git a/main/src/addins/CSharpBinding/MonoDevelop.CSharp.CodeRefactorings/ExtractMethod/ExtractMethodCodeRefactoringProvider.cs b/main/src/addins/CSharpBinding/MonoDevelop.CSharp.CodeRefactorings/ExtractMethod/ExtractMethodCodeRefactoringProvider.cs
new file mode 100644
index 0000000000..9ad0da4356
--- /dev/null
+++ b/main/src/addins/CSharpBinding/MonoDevelop.CSharp.CodeRefactorings/ExtractMethod/ExtractMethodCodeRefactoringProvider.cs
@@ -0,0 +1,104 @@
+// 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.Composition;
+using Microsoft.CodeAnalysis.CodeRefactorings;
+using System.Threading.Tasks;
+using Microsoft.CodeAnalysis;
+using System;
+using Microsoft.CodeAnalysis.CodeActions;
+using Microsoft.CodeAnalysis.Text;
+using System.Threading;
+using ICSharpCode.NRefactory6.CSharp.ExtractMethod;
+using ICSharpCode.NRefactory6.CSharp.Refactoring;
+using MonoDevelop.Core;
+using MonoDevelop.Ide;
+using ICSharpCode.NRefactory6.CSharp;
+
+namespace MonoDevelop.CSharp.CodeRefactorings.ExtractMethod
+{
+	[ExportCodeRefactoringProvider(LanguageNames.CSharp, Name = PredefinedCodeRefactoringProviderNames.ExtractMethod), Shared]
+	internal class ExtractMethodCodeRefactoringProvider : CodeRefactoringProvider
+	{
+		public override async Task ComputeRefactoringsAsync(CodeRefactoringContext context)
+		{
+			// Don't bother if there isn't a selection
+			var textSpan = context.Span;
+			if (textSpan.IsEmpty)
+			{
+				return;
+			}
+			var document = context.Document;
+			var cancellationToken = context.CancellationToken;
+
+			var workspace = document.Project.Solution.Workspace;
+			if (workspace.Kind == WorkspaceKind.MiscellaneousFiles)
+			{
+				return;
+			}
+
+			var activeInlineRenameSession = IdeApp.Workbench.ActiveDocument.Editor.EditMode != MonoDevelop.Ide.Editor.EditMode.Edit;
+			if (activeInlineRenameSession)
+			{
+				return;
+			}
+			var model = await context.Document.GetSemanticModelAsync (context.CancellationToken).ConfigureAwait (false);
+			if (model.IsFromGeneratedCode (context.CancellationToken))
+				return;
+			
+			if (cancellationToken.IsCancellationRequested)
+			{
+				return;
+			}
+
+			var action = await GetCodeActionAsync(document, textSpan, cancellationToken: cancellationToken).ConfigureAwait(false);
+			if (action == null)
+			{
+				return;
+			}
+
+			context.RegisterRefactoring(action.Item1);
+		}
+
+		static CSharpExtractMethodService service = new CSharpExtractMethodService ();
+
+		private async Task<Tuple<CodeAction, string>> GetCodeActionAsync(
+			Document document,
+			TextSpan textSpan,
+			CancellationToken cancellationToken)
+		{
+			var options = document.Project.Solution.Workspace.Options;
+			try {
+				var result = await service.ExtractMethodAsync(
+					document,
+					textSpan,
+					options,
+					cancellationToken).ConfigureAwait(false);
+
+				if (result.Succeeded || result.SucceededWithSuggestion)
+				{
+					var description = options.GetOption(ExtractMethodOptions.AllowMovingDeclaration, document.Project.Language) ?
+						GettextCatalog.GetString ("Extract Method + Local") : GettextCatalog.GetString ("Extract Method");
+
+					var codeAction = new DocumentChangeAction(textSpan, DiagnosticSeverity.Info, description, (c) => AddRenameAnnotationAsync(result.Document, result.InvocationNameToken, c));
+					var methodBlock = result.MethodDeclarationNode;
+
+					return Tuple.Create<CodeAction, string>(codeAction, methodBlock.ToString());
+				}
+			} catch (Exception) {
+				// currently the extract method refactoring crashes often. Ignore the roslyn issues for now.
+			}
+			return null;
+		}
+
+		private async Task<Document> AddRenameAnnotationAsync(Document document, SyntaxToken invocationNameToken, CancellationToken cancellationToken)
+		{
+			var root = await document.GetSyntaxRootAsync(cancellationToken).ConfigureAwait(false);
+
+			var finalRoot = root.ReplaceToken(
+				invocationNameToken,
+				invocationNameToken.WithAdditionalAnnotations(RenameAnnotation.Create()));
+
+			return document.WithSyntaxRoot(finalRoot);
+		}
+	}
+}
+\ No newline at end of file