Add refactoring to convert normal (or verbatim) strings to raw strings.

src/Compilers/Test/Core/Traits/Traits.cs

@@ -74,6 +74,7 @@ public static class Features
             public const string CodeActionsConvertLocalFunctionToMethod = "CodeActions.ConvertLocalFunctionToMethod";
             public const string CodeActionsConvertNumericLiteral = "CodeActions.ConvertNumericLiteral";
             public const string CodeActionsConvertQueryToForEach = "CodeActions.ConvertQueryToForEach";
+            public const string CodeActionsConvertRegularToRawString = "CodeActions.CodeActionsConvertRegularToRawString";
             public const string CodeActionsConvertSwitchStatementToExpression = "CodeActions.ConvertSwitchStatementToExpression";
             public const string CodeActionsConvertToInterpolatedString = "CodeActions.ConvertToInterpolatedString";
             public const string CodeActionsConvertToIterator = "CodeActions.ConvertToIterator";

src/EditorFeatures/CSharp/RawStringLiteral/RawStringLiteralCommandHandler_Return.cs

@@ -90,15 +90,13 @@ SyntaxKind.InterpolatedSingleLineRawStringStartToken or
                 return false;
             }
 
-            var indentation = GetPreferredIndentation(document, token, cancellationToken);
+            var indentation = token.GetPreferredIndentation(document, cancellationToken);
 
             var newLine = document.Project.Solution.Options.GetOption(FormattingOptions.NewLine, LanguageNames.CSharp);
 
             using var transaction = CaretPreservingEditTransaction.TryCreate(
                 CSharpEditorResources.Split_string, textView, _undoHistoryRegistry, _editorOperationsFactoryService);
 
-            var indentService = document.GetRequiredLanguageService<IIndentationService>();
-
             var edit = subjectBuffer.CreateEdit();
 
             var sourceText = document.GetTextSynchronously(cancellationToken);
@@ -116,45 +114,5 @@ SyntaxKind.InterpolatedSingleLineRawStringStartToken or
             transaction?.Complete();
             return true;
         }
-
-        private static string GetPreferredIndentation(Document document, SyntaxToken token, CancellationToken cancellationToken)
-        {
-            var sourceText = document.GetTextSynchronously(cancellationToken);
-            var tokenLine = sourceText.Lines.GetLineFromPosition(token.SpanStart);
-            var firstNonWhitespacePos = tokenLine.GetFirstNonWhitespacePosition();
-            Contract.ThrowIfNull(firstNonWhitespacePos);
-            if (firstNonWhitespacePos.Value == token.SpanStart)
-            {
-                // token was on it's own line.  Start the end delimiter at the same location as it.
-                return tokenLine.Text!.ToString(TextSpan.FromBounds(tokenLine.Start, token.SpanStart));
-            }
-
-            // Token was on a line with something else.  Determine where we would indent the token if it was on the next
-            // line and use that to determine the indentation of the final line.
-
-            var options = document.Project.Solution.Options;
-            var newLine = options.GetOption(FormattingOptions.NewLine, LanguageNames.CSharp);
-
-            var annotation = new SyntaxAnnotation();
-            var newToken = token.WithAdditionalAnnotations(annotation);
-            newToken = newToken.WithLeadingTrivia(newToken.LeadingTrivia.Add(SyntaxFactory.EndOfLine(newLine)));
-
-            var root = document.GetRequiredSyntaxRootSynchronously(cancellationToken);
-            var newRoot = root.ReplaceToken(token, newToken);
-            var newDocument = document.WithSyntaxRoot(newRoot);
-            var newText = newDocument.GetTextSynchronously(cancellationToken);
-
-            var newTokenLine = newText.Lines.GetLineFromPosition(newRoot.GetAnnotatedTokens(annotation).Single().SpanStart);
-
-            var indentStyle = document.Project.Solution.Options.GetOption(FormattingOptions.SmartIndent, LanguageNames.CSharp);
-            var indenter = document.GetRequiredLanguageService<IIndentationService>();
-
-            var indentation = indenter.GetIndentation(newDocument, newTokenLine.LineNumber, indentStyle, cancellationToken);
-
-            return indentation.GetIndentationString(
-                newText,
-                options.GetOption(FormattingOptions.UseTabs, LanguageNames.CSharp),
-                options.GetOption(FormattingOptions.TabSize, LanguageNames.CSharp));
-        }
     }
 }