es2020/test.js

browserify transform that compiles a selection of ES6 to valid ES5

const test = require('tape')
const browserify = require('browserify')
const sourceMap = require('convert-source-map')
const fs = require('fs')
const path = require('path')
const es2020 = require('./')

test('transpilation', function (t) {
  t.plan(4)

  browserify()
    .add('example.js')
    .transform(es2020)
    .bundle(function (err, code) {
      if (err) return t.end(err)
      code = String(code)

      t.notOk(code.includes('=>'), 'transpiles arrow functions')
      t.notOk(code.includes('`'), 'transpiles template literals')
      t.notOk(code.includes('`'), 'transpiles const assignments')
      t.notOk(code.includes('sourceMap'), 'does not build source maps by default')
    })
})

test('source maps', function (t) {
  t.plan(2)

  browserify({
    debug: true
  })
  .add('example.js')
  .transform(es2020)
  .bundle(function (err, code) {
    if (err) return t.end(err)
    code = String(code)

    const data = sourceMap.fromSource(code)
    const original = {
      code: data.getProperty('sourcesContent')[1],
      path: data.getProperty('sources')[1]
    }

    t.equal(original.code, fs.readFileSync(path.resolve(__dirname, 'example.js'), 'utf8'))
    t.equal(original.path, 'example.js')
  })
})

test('JSON files', function (t) {
  t.plan(2)

  browserify()
    .add('example.json')
    .transform(es2020)
    .bundle(function (err, code) {
      if (err) return t.end(err)
      code = String(code)

      t.assert(code.includes('same'), 'preserves key')
      t.assert(code.includes('as it ever was'), 'preserves value')
    })
})

test('handle errors', function (t) {
  t.plan(1)

  browserify({
    debug: true
  })
  .add('LICENSE')
  .transform(es2020)
  .bundle(function (err, code) {
    t.ok(err, 'handles error')
  })
})