Fix default API export

[filipesilva]

Also re-export the API as default export to keep compatibility with existing CommonJS tooling.

Fix #251.

Followup to #209.

[filipesilva]

I tested this with the import code from terser-webpack-plugin:

function _interopRequireDefault(obj) { return obj && obj.__esModule ? obj : { default: obj }; }
var _terser = _interopRequireDefault(require('./'));
console.log(_terser.default.minify)
console.log(_terser.minify)

[kopax]

Can we passe and release this fix please ?

[csvan]

Would greatly appreciate a quick merge and release of this - currently most projects using https://github.com/webpack-contrib/terser-webpack-plugin are affected and suffer broken builds due to this.

[filipesilva]

Just a friendly reminder for everyone to be patient please before this thread grows further.

It's 11pm (on @fabiosantoscode timezone) on a Saturday. Maintainers are people with their own lives too.

It always sucks when software breaks. But everyone's software breaks. Let's just subscribe to this issue and give maintainers time to sort things out.

Here are some things you can do right now to alleviate this problem in your projects:

• @sodatea posted (Terser TypeError: Cannot read property 'minify' of undefined vuejs/vue-cli#3407 (comment)) how you can force your project to use an older version of terser
• you can use https://github.com/ds300/patch-package to locally patch terser@3.16.0 with the dist folder of this PR
• keeping a lockfile (either package.lock or yarn.lock) on your project helps prevent dependency updates from happening unless they are really needed

[sokra]

For full compat maybe even export the full namespace object instead of only the minify function.

export * as default from "./main";

[filipesilva]

You mean in another file, right? Maybe something like:

• move contents of main.js to api.js
• current main.ts becomes:

export * from "./api";
export * as default from "./api";

I think that makes sense, but would like to know what @fabiosantoscode thinks of the extra file.

[thebjorn]

Please don't let perfect be the enemy of good-enough. This broke the entire ecosystem for webpack production builds, so I would prefer a very targeted fix that can be published quickly. Any remaining issues can be resolved in another PR. It's about nine hours until start-of-work-week in Asia, and I'm guessing the pain will increase dramatically... Is @fabiosantoscode the only person who can push a release?

[TrySound]

Let's fix plugin instead
https://github.com/webpack-contrib/terser-webpack-plugin/blob/master/src/minify.js#L4

[sokra]

You mean in another file, right?

I really meant this file. This reference the exports of the file itself. Yes it's circular, but fine here.

Extra file would also work.

Let's fix plugin instead

Also possible and we probably will do this if this won't get fixed here, but keep in mind that the problem was caused by a breaking change released as minor version and terser-webpack-plugin is probably not the only one consuming terser this way. Other libs are probably also broken because of this breaking change, maybe unnoticed because they are less often used.

If the intend is to not add such a compat thing that's also fine, but it would be great to release the commit as major version instead (which may makes sense anyway as it also increases the minimum supported node.js version from 4 to 6).

[filipesilva]

@sokra couldn't get it to work with the syntax your provided:

[!] Error: Unexpected token
main.js (47:9)
45:
46:
47: export * as default from "./main";
             ^
Error: Unexpected token

Instead used this:

import * as terser from './main';
export default terser;

PR is updated.

[timneutkens]

Anything my team can do to help here?

[TrySound]

FYI rollup plugin is not broken :)
https://github.com/TrySound/rollup-plugin-terser/blob/master/transform.js#L1

[exoego]

@filipesilva
I appreciate for your hard work in this PR!!

Could regression test be added for this issue in this PR or followup, to prevent same issue in future release?

[fabiosantoscode]

Nice PR, but the issue got fixed already. Should have merged this! Fixed in v3.16.1

[filipesilva]

03b0876 was merged to fix the same problem.

I tested it with the same test as in #254 (comment):

function _interopRequireDefault(obj) { return obj && obj.__esModule ? obj : { default: obj }; }
var _terser = _interopRequireDefault(require('./'));
console.log(_terser.default.minify)
console.log(_terser.minify)

$ node test-import.js
[Function]
undefined

This means that, when using that compat code, now _terser.default.minify exists but _terser.minify does not.

As far as I can tell, that fix now collides with the fix that was merged in terser-webpack-plugin (webpack-contrib/terser-webpack-plugin#69) and resurfaces the problem. I am not sure how this affects https://github.com/TrySound/rollup-plugin-terser (cc @TrySound).

@fabiosantoscode WDYT of reverting 03b0876 and merging this PR instead? Maybe there's a better way about this that I am not seeing right now.

Edit: just tried using terser-webpack-plugin@1.2.2 which uses terser@3.16.1 and see no problem whatsoever. I think my test here was bad. Sorry about that!

[Tenemo]

3.16.1 does fix the issue, built without problems with the latest webpack. Thanks for the fix!

[fabiosantoscode]

I decided not to merge it because I prefer a purely commonjs approach, for compatibility. ⛄