code: function appendDataSync(outPath, data, opts_) {
    // Run append file to delegate creating a new file if none exists
    if (opts_ && (opts_.makeDirectories === true || opts_.makeDirs === true)) {
      makeDirectoriesSync(outPath);
    }
    opts_ = omit(opts_, ['makeDirectories', 'makeDirs']);
    fs.appendFileSync(outPath, '');
    var existingData = readDataSync(outPath);
    if (!underscore.isEmpty(existingData)) {
      if (Array.isArray(existingData)) {
        data = existingData.concat(data);
      } else if ((typeof existingData === 'undefined' ? 'undefined' : _typeof(existingData)) === 'object') {
        data = extend$1({}, existingData, data);
      }
    }
    writeDataSync(outPath, data, opts_);
    return data;
  }
docs: /* istanbul ignore next /* istanbul ignore next 
  Synchronous version of {@link writers#appendData}. See that function for supported formats
  
  @function appendDataSync
  @param {String} filePath File to append to
  @param {Array|Object} data The new data to append
  @param {Object} [options] Optional options object passed to {@link writeData}. See that function for format-specific options.
  @returns {Object} The combined data that was written
  
  @example
  io.appendDataSync('path/to/data.json', jsonData)
  
  io.appendDataSync('path/to/create/to/data.csv', flatJsonData, {makeDirectories: true})