Testing Handlebars Helper with Ember CLI

number-to-currency-test.js

import numberToCurrency from '../../helpers/number-to-currency';

module('number-to-currency Handlebars Helper');

test('convert invalid input to zero', function() {
  equal('€ 0,00', numberToCurrency._rawFunction(null));
  equal('€ 0,00', numberToCurrency._rawFunction(undefined));
});

test('handle single digit input', function() {
  equal('€ 0,00', numberToCurrency._rawFunction(0));
  equal('€ 0,09', numberToCurrency._rawFunction(9));
});

test('handle two digit input', function() {
  equal('€ 0,99', numberToCurrency._rawFunction(99));
});

test('handle multi digit input', function() {
  equal('€ 1,99', numberToCurrency._rawFunction(199));
  equal('€ 100,99', numberToCurrency._rawFunction(10099));
  equal('€ 1.000,99', numberToCurrency._rawFunction(100099));
  equal('€ 1.000.000,99', numberToCurrency._rawFunction(100000099));
});

number-to-currency.js

import Ember from 'ember';

export default Ember.Handlebars.makeBoundHelper(function(value) {
  if (value === null) {
    value = 0;
  }

  if (isNaN(value)) {
    value = 0;
  }

  value = value.toString();

  while (value.length < 3) {
    value = '0' + value;
  }

  var fractionalPart = value.slice(-2);
  var integerPart = value.slice(0, -2).replace(/\B(?=(\d{3})+(?!\d))/g, '.');

  return '€ ' + integerPart + ',' + fractionalPart;
});