babelify

Babel browserify transform

Installation

$ npm install --save-dev babelify

Usage

CLI

$ browserify script.js -t babelify --outfile bundle.js

Node

var fs = require("fs");
var browserify = require("browserify");
var babelify = require("babelify");
browserify({ debug: true })
  .transform(babelify)
  .require("./script.js", { entry: true })
  .bundle()
  .on("error", function (err) { console.log("Error : " + err.message); })
  .pipe(fs.createWriteStream("bundle.js"));

Options

browserify().transform(babelify.configure({
  blacklist: ["regenerator"]
}))

$ browserify -d -e script.js -t [ babelify --blacklist regenerator ]

Enable Experimental Transforms

By default Babel's experimental transforms are disabled. You can turn them on individually by passing optional as a configuration option.

browserify().transform(babelify.configure({
  optional: ["es7.asyncFunctions"]
}))

$ browserify -d -e script.js -t [ babelify --optional es7.asyncFunctions ]

Alternatively, you can enable an entire TC39 category of experimental ES7 features via the stage configuration option.

browserify().transform(babelify.configure({
  stage: 0
}))

$ browserify -d -e script.js -t [ babelify --stage 0 ]

Customising extensions

By default all files with the extensions .js, .es, .es6 and .jsx are compiled. You can change this by passing an array of extensions.

NOTE: This will override the default ones so if you want to use any of them you have to add them back.

browserify().transform(babelify.configure({
  extensions: [".babel"]
}))

$ browserify -d -e script.js -t [ babelify --extensions .babel ]

Relative source maps

Browserify passes an absolute path so there's no way to determine what folder it's relative to. You can pass a relative path that'll be removed from the absolute path with the sourceMapRelative option.

browserify().transform(babelify.configure({
  sourceMapRelative: "/Users/sebastian/Projects/my-cool-website/assets"
}))

$ browserify -d -e script.js -t [ babelify --sourceMapRelative . ]

Additional options

browserify().transform(babelify.configure({
  // Optional ignore regex - if any filenames **do** match this regex then they
  // aren't compiled
  ignore: /regex/,

  // Optional only regex - if any filenames **don't** match this regex then they
  // aren't compiled
  only: /my_es6_folder/
}))

$ browserify -d -e script.js -t [ babelify --ignore regex --only my_es6_folder ]

ES6 Polyfill

As a convenience, the babelify polyfill is exposed in babelify. If you've got a browserify-only package this may alleviate the necessity to have both babel & babelify installed.

// In browser code
require("babelify/polyfill");

FAQ

Why aren't files in node_modules being transformed?

This is default browserify behaviour and can not be overriden. A possible solution is to add:

{
  "browserify": {
    "transform": ["babelify"]
  }
}

to the root of all your modules package.json that you want to be transformed. If you'd like to specify options then you can use:

{
  "browserify": {
    "transform": [["babelify", { "optional": ["es7.asyncFunctions"] }]]
  }
}