Testing Javascript with standalone jasmine

standalone-jasmine.txt

If this link doesn't work, go to next step:
https://github.com/jasmine/jasmine/releases
download latest version of standalone jasmine from that link or search Google for "standalone jasmine".

Follow this tutorial:
https://code.tutsplus.com/tutorials/testing-your-javascript-with-jasmine--net-21229

Here's my version of the code:
// src/convert.js
function Convert(iAmount, sUnitFrom) {
  if (!['in', 'cm', 'litres', 'usgallons'].includes(sUnitFrom)) {
    throw new Error('invalid from unit')
  }
  let conv = {
    cm: 2.54,
    yards: 0.0109361,
    usgallons: 0.264172,
    cups: 16
  }
  return {
    to: function(sUnitTo) {
      if (typeof conv[sUnitTo] === 'undefined') {
        throw new Error('invalid to unit')
      }
      return iAmount * conv[sUnitTo]
    }
  }
}

// spec/convertSpec.js
/* global describe */
/* global it */
/* global expect */
/* global Convert */

describe('Convert library', function() {
  let expected = -1
  let actual = -1
  describe('distance converter', function() {
    it('converts inches to cm', function() {
      actual = Convert(12, 'in').to('cm')
      expected = 30.48
      expect(actual).toEqual(expected)
      actual = Convert(1, 'in').to('cm')
      expected = 2.54
      expect(actual).toEqual(expected)
    })
    it('converts cm to yards', function(){
      actual = Convert(2000, 'cm').to('yards')
      expected = 21.87
      expect(actual).toBeCloseTo(expected, 2)
    })
  })
  describe('volume converter', function() {
    it('converts litres to usgallons', function() {
      actual = Convert(3, 'litres').to('usgallons')
      expected = 0.79
      expect(actual).toBeCloseTo(expected, 2)
    })
    it('converts usgallons to cups', function() {
      actual = Convert(2, 'usgallons').to('cups')
      expected = 32
      expect(actual).toEqual(expected)
    })
  })
  it('throws an error with invalid from unit', function() {
    expect(
      function() {
        Convert(1, 'dollar').to('yens')
      }
    ).toThrow(new Error('invalid from unit'))
  })
  it('throws an error with invalid to unit', function() {
    expect(
      function() {
        Convert(1, 'cm').to('furlongs')
      }
    ).toThrow(new Error('invalid to unit'))
  })
})