Vite resolves import with browser field during SSR

[benmccann]

Describe the bug

The presence of a browser field is causing Vite to try to load the client-side version of an isomorphic package on the server-side.

Reproduction

npm init svelte@next
npm install
npm install websocket
sed -i "s/<script>/<script>\n\timport { w3cwebsocket } from 'websocket';\n\tconsole.log(w3cwebsocket);\n/" ./src/routes/index.svelte
npm run dev

System Info

Output of npx envinfo --system --npmPackages vite,@vitejs/plugin-vue --binaries --browsers:

  System:
    OS: Linux 5.8 Ubuntu 20.04.2 LTS (Focal Fossa)
    CPU: (8) x64 Intel(R) Core(TM) i7-10510U CPU @ 1.80GHz
    Memory: 17.36 GB / 31.14 GB
    Container: Yes
    Shell: 5.0.17 - /bin/bash
  Binaries:
    Node: 14.16.0 - ~/.nvm/versions/node/v14.16.0/bin/node
    npm: 7.9.0 - ~/.nvm/versions/node/v14.16.0/bin/npm
  Browsers:
    Chrome: 89.0.4389.114
    Firefox: 87.0
  npmPackages:
    vite: ^2.1.0 => 2.1.5

Used package manager: npm

Logs

3:26:21 PM [vite] Error when evaluating SSR module /node_modules/websocket/lib/browser.js?v=364f06a3:
ReferenceError: require is not defined
    at /node_modules/websocket/lib/browser.js?v=364f06a3:15:25

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[stupidawesome]

Can this issue be reopened? The mentioned PR doesn't completely resolve this issue.

See related: supabase/supabase-js#154 (comment)

[GrygrFlzr]

@stupidawesome Looking at your linked comment, it looks like that should be opened as a new issue instead, because the root of that issue seems to be Vite only resolving dependencies once + incorrectly resolving isomorphic packages, whereas this seems to be only concerned with the browser field in package.json.