code: function SelectionFold(cm, start) {
          if (!cm.somethingSelected()) {
              return;
          }
  
          var from = cm.getCursor("from"),
              to  = cm.getCursor("to");
          if (from.line === start.line) {
              return {from: from, to: to};
          }
      }
docs: This helper returns the start and end range representing the current selection in the editor.
  @param   {Object} cm    The Codemirror instance
  @param   {Object} start A Codemirror.Pos object {line, ch} representing the current line we are
  checking for fold ranges
  @returns {Object} The fold range, {from, to} representing the current selection.