Invalid commonjs default import in prod builds

[marvinhagemeister]

Describe the bug

We received a bug report (see: preactjs/preset-vite#75) for the Preact vite preset that there is an issue with importing react-datetime. Upon further inspection this issue isn't related to Preact and can be reproduced with the React preset too. I was able to narrow it down to a difference in how default exports from commonjs modules are treated.

import DateTime from 'react-datetime';

if (typeof DateTime !== 'function') {
  // We hit this path only in prod builds
  throw new Error('This is a bug');
}
console.log('it works');

In development mode everything works as expected. But in production mode the default export is wrapped into an object: { default: ... } with a default property which contains the expected value. This additional indirection causes production builds to be incorrect.

Reproduction

https://stackblitz.com/edit/vitejs-vite-k6uuun?file=main.js

Steps to reproduce

1. Run npm install
2. Run npm run build
3. Run npm run preview
4. Check console

System Info

Not relevant, happens on all systems.

  System:
    OS: macOS 13.3.1
    CPU: (8) arm64 Apple M1 Pro
    Memory: 90.64 MB / 16.00 GB
    Shell: 5.9 - /bin/zsh
  Binaries:
    Node: 19.7.0 - /opt/homebrew/bin/node
    Yarn: 1.22.19 - /opt/homebrew/bin/yarn
    npm: 9.5.0 - /opt/homebrew/bin/npm
  Browsers:
    Chrome: 112.0.5615.137
    Chrome Canary: 114.0.5734.0
    Firefox: 111.0.1
    Safari: 16.4
  npmPackages:
    @vitejs/plugin-react: ^4.0.0 => 4.0.0 
    vite: ^4.3.2 => 4.3.2

Used Package Manager

npm

Logs

No response

Validations

• Follow our Code of Conduct
• Read the Contributing Guidelines.
• Read the docs.
• Check that there isn't already an issue that reports the same bug to avoid creating a duplicate.
• Make sure this is a Vite issue and not a framework-specific issue. For example, if it's a Vue SFC related bug, it should likely be reported to vuejs/core instead.
• Check that this is a concrete bug. For Q&A open a GitHub Discussion or join our Discord Chat Server.
• The provided reproduction is a minimal reproducible example of the bug.

[stackblitz]

Start a new pull request in StackBlitz Codeflow.

• vitejs-vite-k6uuun (Open reproduction)

[sapphi-red]

This didn't work with 4.3.2 but it worked with the current main branch (5731ac9caaef629e892e20394f0cc73c565d9a87). I guess rollup/plugins#1455 fixed this.
This will work in the next version. 👍