[@rollup/plugin-commonjs] commonjs does not recognize named cjs exports

[GauBen]

• Rollup Plugin Name: @rollup/plugin-commonjs
• Rollup Plugin Version: latest (^25.0.7)
• Rollup Version: latest (^4.10.0)
• Operating System (or Browser):
• Node Version: 20
• Link to reproduction: https://stackblitz.com/edit/rollup-repro-axmnsg?file=src%2Fmain.cjs

I'm trying to transpile CJS to ESM until prisma/prisma#5030 is addressed. I'm having a hard time doing so as I can't quite get the pieces together.

Expected Behavior

The commonjs plugin properly detects all named exports

Actual Behavior

No named exports are found

Additional Information

There is a node-backed package that does a pretty solid named exports analysis, which works for my specific use case. I've added a npm run cjs-lex command in the repro to show how it works

[bhovhannes]

I think my use case is related. I noticed that Object.defineProperty(exports, ...) syntax is also detected by cjs-module-lexer.

My input file input.js:

import {foo} from "foo"
console.log(foo)

The foo package is a pure CJS package and has the following content:

// foo/index.js
Object.defineProperty(exports, "foo", { enumerable: true, get: function () { return 123; } });

A bundle produced by Rollup outputs undefined when executed, while it should output value of foo - 123.