All files / src/directReaders readTsv.js

100% Statements 0/0
100% Branches 2/2
100% Functions 0/0
100% Lines 0/0
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35                                                                     
import readData from '../readers/readData'
import parserTsv from '../parsers/tsv'
 
/**
 * Asynchronously read a tab-separated value file. Returns an empty array if file is empty.
 *
 * @function readTsv
 * @param {String} filePath Input file path
 * @param {Function|Object} [map] Optional map function or an object with `map` key that is a function. Called once for each row with the signature `(row, i)` and must return the transformed row. See example below or d3-dsv documentation for details.
 * @param {Function} callback Has signature `(err, data)`
 *
 * @example
 * io.readTsv('path/to/data.tsv', function (err, data) {
 *   console.log(data) // Json data
 * })
 *
 * // Transform values on load
 * io.readTsv('path/to/data.tsv', function (row, i, columns) {
 *     console.log(columns) // [ 'name', 'occupation', 'height' ]
 *     row.height = +row.height // Convert this value to a number
 *     return row
 * }, function (err, data) {
 *   console.log(data) // Json data with casted values
 * })
 */
export default function readTsv (filePath, opts_, cb) {
  var parserOptions
  if (typeof cb === 'undefined') {
    cb = opts_
  } else {
    parserOptions = typeof opts_ === 'function' ? {map: opts_} : opts_
  }
  readData(filePath, {parser: parserTsv, parserOptions: parserOptions}, cb)
}