private static Task <Document> RefactorAsync(
            Document document,
            EnumDeclarationSyntax enumDeclaration,
            TextSpan span,
            CancellationToken cancellationToken)
        {
            SyntaxTrivia trivia = enumDeclaration.FindTrivia(span.Start);

            SyntaxToken token = trivia.Token;

            EnumMemberDeclarationSyntax enumMemberDeclaration = token
                                                                .GetPreviousToken()
                                                                .Parent
                                                                .FirstAncestorOrSelf <EnumMemberDeclarationSyntax>();

            int enumMemberIndex = enumDeclaration.Members.IndexOf(enumMemberDeclaration);

            SyntaxTriviaList trailingTrivia = token.TrailingTrivia;

            SyntaxToken newToken = token.WithTrailingTrivia(trailingTrivia.Skip(trailingTrivia.IndexOf(trivia) + 1));

            EnumDeclarationSyntax newEnumDeclaration = enumDeclaration.ReplaceToken(token, newToken);

            var settings = new DocumentationCommentGeneratorSettings(ImmutableArray.Create(_leadingSlashesRegex.Replace(trivia.ToString(), "")));

            EnumMemberDeclarationSyntax newEnumMemberDeclaration = newEnumDeclaration.Members[enumMemberIndex].WithNewSingleLineDocumentationComment(settings);

            newEnumDeclaration = newEnumDeclaration.WithMembers(newEnumDeclaration.Members.ReplaceAt(enumMemberIndex, newEnumMemberDeclaration));

            return(document.ReplaceNodeAsync(enumDeclaration, newEnumDeclaration, cancellationToken));
        }