date-fns does not provide an export named 'default' when imported in specific order with @material-ui/pickers

[hmaurer]

Describe the bug

When the packages date-fns@2.16.1 and @material-ui/pickers@4.0.0-alpha.12 are used and date-fns is imported before @material-ui/pickers/adapter/date-fns, the following error is observed:

Uncaught SyntaxError: The requested module '/node_modules/.vite/date-fns.js?v=cf140b8b' does not provide an export named 'default'

If date-fns is imported after @material-ui/pickers/adapter/date-fns, no error is observed.

Reproduction

https://gist.github.com/hmaurer/b6dd7048a1544d7190d42e48f130d30d

git clone git@gist.github.com:b6dd7048a1544d7190d42e48f130d30d.git vite-issue-1847
cd vite-issue-1847
npm i && npm run dev

Open http://localhost:3000. You should observe the following error in the web console:

Uncaught SyntaxError: The requested module '/node_modules/.vite/date-fns.js?v=cf140b8b' does not provide an export named 'default'

Now, in main.js, swap the order of imports of date-fns and @material-ui/pickers/adapter/date-fns, run rm -r node_modules/.vite and then npm run dev. You shouldn't observe an error in the console anymore.

System Info

• vite version: 2.0.0-beta.61
• Operating System: MacOS Catalina 10.15.7
• Node version: v12.18.4
• Package manager (npm/yarn/pnpm) and version: NPM 6.14.6