Babel throws an error when a preset is passed options but doesn't accept them

[ericf]

I ran into an issue using this lib because it passes options ({modules: false}) to all presets; e.g. babel-preset-react, even if that preset doesn't accept options. When this happens Babel errors out.

[deavial]

same issue and have not been able to compile code

[sebinsua]

Same issue here. :/

This seems to fix it:

function mapPreset(preset, options) {
  var info = getPresetInfo(preset);

  if (!info) {
    return preset;
  }

  if (options.findRollupPresets && hasRollupVersionOfPreset(info.name, options.resolve || resolve.sync)) {
    return [info.name + '-rollup', info.options];
  } else if (options.addModuleOptions) {
    const options = info.name === 'es2015' ? _extends({}, info.options, { modules: false }) : []
    return [info.name].concat(options);
  } else {
    return preset;
  }
}

Not sure which other modules accept options? I just made the change above temporarily so I could publish.

[gabrielcorado]

I'm having the same issue. Any updates?

[brabeji]

To disable that behavior:

...
    plugins: [
        babel(babelrc({ addModuleOptions: false })),
    ],
...

[vitorfox]

@brabeji where do you put that config?

[ramingar]

In your rollup.config.js.

[rhysburnie]

Hi @eventualbuddha,

I think the fix described by @sebinsua is much better.
Currently it just blindly adds { "modules": false } to every preset even though most don't have that option and will complain.

I don't consider babelrc({ addModuleOptions: false }) to be a fix...

In that situation you will then get an error (babel plugin) It looks like your Babel configuration specifies a module transformer. Please disable it.

ie. you have to add in manually to your .babelrc, however in many cases (for instance using AVA test suite) the preset needs to be "es2015" or ["es2015", { "modules": true}]" so the test runner can interpret import.

Simply put the mapPreset function should only add modules: false if the preset is one that actually has the option modules as suggested by @sebinsua (whether that includes more presets than es2015 I don't know).

I was having issues because I need the following for AVA (and any other normal es w/ modules)

{
  "presets": [
    "es2015",
    "stage-2"
  ]
}

but this plugin incorrectly adds ["stage-2", { "modules": false }]

For the time being I have to loop over the presets returned by babelrc() and remove "modules": false from all but es2015. before passing it to the rollup babel plugin.

UPDATE

In addition to this it turns out some presets can also refuse any options at all! :(

So in the case of 'stage-2' I was getting an error babel-preset-stage-2/lib/index.js which does not accept options..

So even if modules option was only added if es2015, the following will still add an option to some presets that don't accept any options (because it returns the array).

  } else if (options.addModuleOptions) {
    return [info.name, { ...info.options, modules: false }];
  }

---

This is my hacky fix in my config to undo any problematic preset option transformation.

const rc = babelrc();
const doesNotAcceptOptions = ['stage-2'];
const acceptsOptionModules = ['es2015'];
rc.presets.forEach((preset, i) => {
  if (doesNotAcceptOptions.indexOf(preset[0]) > -1) {
    rc.presets[i] = preset[0];
  } else if (acceptsOptionModules.indexOf(preset[0]) === -1) {
    delete preset[1].modules; // eslint-disable-line
  }
});
// console.log(JSON.stringify(rc, null, 2));

in config...

  plugins: [
    babel(rc),
  ],

[eventualbuddha]

I'm happy to let someone else take over this project, or to review a PR that fixes this.

[robinvdvleuten]

You can quite easily pass custom options to babel and still have a global .babelrc file;

import babel from 'rollup-plugin-babel';

export default {
  plugins: [
    babel({
      presets: [['env', { modules: false }], 'stage-2'],
      exclude: 'node_modules/**',
      babelrc: false
    }),
  ],
};

Hopefully it will help anyone 😄