Workbook.js

/**
 * Emulates VBA File System
 * 
 * @todo separate out workbook APIs from FileSystem APIs
 * @todo implement current_directory
 */
var FileSystem = {
  current_directory: "<ToBeDefined>",
  api_workbook_open: api_workbook_open_,
};

/**
 * Emulates workbook.Open(filename) API 
 * Opens the corresponding spreadsheet in a new tab. 
 *
 * @param {string} path The local file path in the Excel file
 * @return {Spreadsheet} The spreadsheet object of the path
 */
function api_workbook_open_(path) {
  var fileId = FileMapper.getFileId(this.current_directory, path, MimeType.GOOGLE_SHEETS);
  var file = SpreadsheetApp.openById(fileId);
  openURL(file.getUrl(), file.getName() + " file open in new tab");
  return file;
}