this.$renderCell = function()

in lib/ace/layer/gutter.js [303:378]
62 lines of code
25 McCabe index (conditional complexity)

    this.$renderCell = function(cell, config, fold, row) {
        var element = cell.element;
        
        var session = this.session;
        
        var textNode = element.childNodes[0];
        var foldWidget = element.childNodes[1];

        var firstLineNumber = session.$firstLineNumber;
        
        var breakpoints = session.$breakpoints;
        var decorations = session.$decorations;
        var gutterRenderer = session.gutterRenderer || this.$renderer;
        var foldWidgets = this.$showFoldWidgets && session.foldWidgets;
        var foldStart = fold ? fold.start.row : Number.MAX_VALUE;
        
        var className = "ace_gutter-cell ";
        if (this.$highlightGutterLine) {
            if (row == this.$cursorRow || (fold && row < this.$cursorRow && row >= foldStart &&  this.$cursorRow <= fold.end.row)) {
                className += "ace_gutter-active-line ";
                if (this.$cursorCell != cell) {
                    if (this.$cursorCell)
                        this.$cursorCell.element.className = this.$cursorCell.element.className.replace("ace_gutter-active-line ", "");
                    this.$cursorCell = cell;
                }
            }
        }
        
        if (breakpoints[row])
            className += breakpoints[row];
        if (decorations[row])
            className += decorations[row];
        if (this.$annotations[row])
            className += this.$annotations[row].className;
        if (element.className != className)
            element.className = className;

        if (foldWidgets) {
            var c = foldWidgets[row];
            // check if cached value is invalidated and we need to recompute
            if (c == null)
                c = foldWidgets[row] = session.getFoldWidget(row);
        }

        if (c) {
            var className = "ace_fold-widget ace_" + c;
            if (c == "start" && row == foldStart && row < fold.end.row)
                className += " ace_closed";
            else
                className += " ace_open";
            if (foldWidget.className != className)
                foldWidget.className = className;

            var foldHeight = config.lineHeight + "px";
            dom.setStyle(foldWidget.style, "height", foldHeight);
            dom.setStyle(foldWidget.style, "display", "inline-block");
        } else {
            if (foldWidget) {
                dom.setStyle(foldWidget.style, "display", "none");
            }
        }
        
        var text = (gutterRenderer
            ? gutterRenderer.getText(session, row)
            : row + firstLineNumber).toString();
            
        if (text !== textNode.data) {
            textNode.data = text;
        }
        
        dom.setStyle(cell.element.style, "height", this.$lines.computeLineHeight(row, config, session) + "px");
        dom.setStyle(cell.element.style, "top", this.$lines.computeLineTop(row, config, session) + "px");
        
        cell.text = text;
        return cell;
    };