gulpfile.babel.js

// Native
import { join } from 'path'
import { gzipSync } from 'zlib'

// Packages
import gulp from 'gulp'
import babel from 'gulp-babel'
import { transformFile } from 'babel-core'
import size from 'human-size'
import benchmark from 'gulp-benchmark'

gulp.task('transpile', () => {
  gulp
    .src('src/**/*.js')
    .pipe(babel())
    .pipe(gulp.dest('dist'))
})

gulp.task('runtime-size', async () => {
  const files = [
    'stylesheet-registry.js',
    'server.js',
    'style.js',
    'lib/stylesheet.js'
  ]

  const result = await Promise.all(
    files.map(f => join(__dirname, 'src', f)).map(transform)
  )

  const code = result.map(({ code }) => code).join('')

  console.log('-----------------------------------------------')
  console.log('files:', files.join(', '))
  console.log('minified:', size(code.length))
  console.log('minified and gzipped:', size(gzipSync(code).length))
  console.log('-----------------------------------------------')

  function transform(file) {
    return new Promise((resolve, reject) => {
      transformFile(
        file,
        {
          presets: ['babili']
        },
        (err, data) => {
          if (err) {
            return reject(err)
          }
          resolve(data)
        }
      )
    })
  }
})

gulp.task('benchmark', () => {
  gulp
    .src('*.js', {
      read: false,
      cwd: './benchmark'
    })
    .pipe(babel())
    .pipe(benchmark())
})

gulp.task('watch', () => {
  gulp.watch('src/*', ['transpile'])
  gulp.watch('src/lib/*', ['transpile'])
  gulp.watch('benchmark/*.js', ['benchmark'])
})

gulp.task('default', ['transpile', 'watch'])