Modules with 'syntheticNamedExports' need a default export.

[sirgalleto]

Original here

• Rollup Plugin Name: @rollup/plugin-commonjs
• Rollup Plugin Version: 12.0.0
• Rollup Version: 2.10.8
• Operating System (or Browser): MacOS Catalina 10.15.4
• Node Version: 12.16

How Do We Reproduce?

1. Install a commonjs library with a single module.exports.
2. Do a import default. Import from 'library'
3. build with transformMixedEsModules: true.

https://repl.it/repls/StainedOrchidUserinterface

Expected Behavior

If I understand well, the transformMixedEsModules should first patch the default export and then pass it to syntheticNamedExports

Actual Behavior

transformMixedEsModules: true in commonjs() config:

Modules with 'syntheticNamedExports' need a default export. 

[shellscape]

We'll be happy to triage this once you've completed our bug issue template.

[sirgalleto]

@shellscape updated, let me know if I'm missing something.

Thanks!

[lukastaegert]

See ionic-team/rollup-plugin-node-polyfills#6 (comment) for explanation. The actual bug in this plugin will be fixed soon, but your code will still be broken unless you make sure rollup-plugin-node-polyfills is placed AFTER @rollup/plugin-commonjs in your plugins array.