cjs-to-es6 - 将CommonJS转换成ES6模块

jopen 8年前

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.

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