private static void OrganizeWorker(
            SyntaxList <ExternAliasDirectiveSyntax> externAliasList,
            SyntaxList <UsingDirectiveSyntax> usingList,
            bool placeSystemNamespaceFirst,
            out SyntaxList <ExternAliasDirectiveSyntax> organizedExternAliasList,
            out SyntaxList <UsingDirectiveSyntax> organizedUsingList
            )
        {
            if (externAliasList.Count > 0 || usingList.Count > 0)
            {
                // Merge the list of usings and externs into one list.
                // order them in the order that they were originally in the
                // file.
                var initialList = usingList
                                  .Cast <SyntaxNode>()
                                  .Concat(externAliasList)
                                  .OrderBy(n => n.SpanStart)
                                  .ToList();

                if (!initialList.SpansPreprocessorDirective())
                {
                    // If there is a banner comment that precedes the nodes,
                    // then remove it and store it for later.
                    initialList[0] = initialList[
                        0
                                     ].GetNodeWithoutLeadingBannerAndPreprocessorDirectives(out var leadingTrivia);

                    var comparer = placeSystemNamespaceFirst
                        ? UsingsAndExternAliasesDirectiveComparer.SystemFirstInstance
                        : UsingsAndExternAliasesDirectiveComparer.NormalInstance;

                    var finalList = initialList.OrderBy(comparer).ToList();

                    // Check if sorting the list actually changed anything.  If not, then we don't
                    // need to make any changes to the file.
                    if (!finalList.SequenceEqual(initialList))
                    {
                        // Make sure newlines are correct between nodes.
                        EnsureNewLines(finalList);

                        // Reattach the banner.
                        finalList[0] = finalList[0].WithPrependedLeadingTrivia(leadingTrivia);

                        // Now split out the externs and usings back into two separate lists.
                        organizedExternAliasList = finalList
                                                   .Where(t => t is ExternAliasDirectiveSyntax)
                                                   .Cast <ExternAliasDirectiveSyntax>()
                                                   .ToSyntaxList();
                        organizedUsingList = finalList
                                             .Where(t => t is UsingDirectiveSyntax)
                                             .Cast <UsingDirectiveSyntax>()
                                             .ToSyntaxList();
                        return;
                    }
                }
            }

            organizedExternAliasList = externAliasList;
            organizedUsingList       = usingList;
        }