cjs-to-es6

CLI to convert JavaScript files from CommonJS to ES6 modules (aka ES2015 modules, aka JavaScript modules, aka hipster require()). Uses 5to6-codemod under the hood.

Usage

Install it:

npm install -g cjs-to-es6

Then run it:

cjs-to-es6 [ --verbose ] files/directories...

Examples:

cjs-to-es6 index.js             # convert a single file
cjs-to-es6 lib/                 # convert all files in a directory
cjs-to-es6 foo.js bar.js lib/   # convert many files/directories

All files are modified in-place.

Example input and output

In comes CommonJS:

var flimshaw = require('flimshaw');
var twentyEightSkidoo = require('twenty-eight').skidoo;

exports.flubTheDub = 'flubTheDub';
module.exports = 'zings';

Out goes ES6 modules:

import flimshaw from 'flimshaw';
import {skidoo as twentyEightSkidoo} from 'twenty-eight';

export let flubTheDub = 'flubTheDub';
export default 'zings';

Migrating from CommonJS to ES6 modules

Not all uses of CommonJS have a 1-to-1 equivalent in ES6 modules. So you might have to correct some errors manually.

Use --verbose to get detailed output, or follow these general tips:

exports must be at the top level

This is invalid:

if (clownShoes) {
  export default new Clown();
} else {
  export default new RespectableGentleman();
}

Instead do:

var result = clownShoes ? new Clown() : new RespectableGentleman();
export default result;

imports also have to be at the top level

This is invalid:

try {
  import MysterModule from 'mystery-module';
} catch (err) {
  console.log("It's a mystery!");
}

There is no equivalent for this try/catch pattern in ES6 modules.

項目地址： https://github.com/nolanlawson/cjs-to-es6