cli.js

#!/usr/bin/env node
'use strict'
const ora = require('ora')
const meow = require('meow')
const formatBenchmark = require('./format-benchmark')
const ReactBenchmark = require('.')

const cli = meow({
  help: `
Usage
  $ react-benchmark <path>

Options
  <path>          Path to a JavaScript file that exports the function to be benchmarked.
  --debug, -d     Run a development build instead of a production build to aid debugging.
  --devtools, -t  Run Chrome in windowed mode with the devtools open.
  --version       Prints the version.
  --help          Prints this message.
  --updates, -u   Number of component updates to perform (default: 0)

Examples
  $ react-benchmark benchmark.js
  `.trim(),
  flags: {
    debug: {
      type: 'boolean',
      default: false,
      alias: 'd'
    },
    devtools: {
      type: 'boolean',
      default: false,
      alias: 't'
    },
    updates: {
      type: 'number',
      default: 0,
      alias: 'u'
    }
  }
})

let spinner

async function main() {
  if (cli.input.length !== 1) {
    cli.showHelp()
    return
  }

  const [filepath] = cli.input
  const {debug, devtools, updates} = cli.flags

  spinner = ora().start()

  const reactBenchmark = new ReactBenchmark()

  reactBenchmark.on('webpack', () => {
    spinner.text = 'Compiling bundle'
  })

  reactBenchmark.on('server', () => {
    spinner.text = 'Starting server'
  })

  reactBenchmark.on('chrome', () => {
    spinner.text = 'Starting Chrome'
  })

  reactBenchmark.on('start', () => {
    spinner.text = 'Starting benchmark'
  })

  reactBenchmark.on('progress', benchmark => {
    spinner.text = formatBenchmark(benchmark)
  })

  reactBenchmark.on('console', log => {
    spinner.clear()
    // Log to stderr so that stdout only contains the final output
    console.error(`console.${log.type}: ${log.text}`)
    spinner.render()
  })

  const result = await reactBenchmark.run(filepath, {debug, devtools, updates})

  spinner.stop()
  console.log(formatBenchmark(result))
}

main().catch(error => {
  if (spinner) {
    spinner.fail()
  }
  console.error(error)
  process.exitCode = 1
})