files are being added to `assets` even when `build.rollupOptions.output` options are configured

[skratchdot]

I'm using React Router as a...

framework

Reproduction

I ran into an issue when upgrading from remix v2 to react-router v7. At work, for some reason our github pages enterprise integration does not render assets/_index.js files (not sure where or why that happens). In any case, I was able to "fix" this issue in remix v2 by updating my vite.config.ts file with some build.rollupOptions.output options:

  build: {
    rollupOptions: {
      // https://vitejs.dev/config/build-options.html#build-rollupoptions
      output: {
        // https://rollupjs.org/configuration-options/#output-assetfilenames
        assetFileNames: 'myapp-assets/myapp-[name]-[hash][extname]',
        // https://rollupjs.org/configuration-options/#output-chunkfilenames
        chunkFileNames: 'myapp-chunks/myapp-[name]-[hash].js',
        // https://rollupjs.org/configuration-options/#output-entryfilenames
        entryFileNames: 'myapp-entries/myapp-[name]-[hash].js',
      },
    },
  },

When upgrading to react-router v7, the github pages issue popped back up because assets/_index.js files were being written again. I came up with a workaround, but I'd still like to log this bug/issue in the hopes that entryFileNames will be respected in react-router v7 (and we can configure the "assets" folder location/name).

I've created a repo with default remix v2 and react-router v7 apps. I then converted them to spa mode and included the same build.rollupOptions.output options.

• https://github.com/skratchdot/react-router-issue/

Notice the differences in the build output:

• https://github.com/skratchdot/react-router-issue/tree/main/builds

System Info

System:
    OS: macOS 15.3.1
    CPU: (10) arm64 Apple M1 Max
    Memory: 669.39 MB / 64.00 GB
    Shell: 5.9 - /bin/zsh
  Binaries:
    Node: 23.7.0 - /opt/homebrew/bin/node
    npm: 10.9.2 - /opt/homebrew/bin/npm
    pnpm: 10.4.1 - /opt/homebrew/bin/pnpm
  Browsers:
    Chrome: 133.0.6943.127
    Chrome Canary: 135.0.7029.0
    Safari: 18.3

Used Package Manager

pnpm

Expected Behavior

When configuring:

• build.rollupOptions.output.assetFileNames
• build.rollupOptions.output.chunkFileNames
• build.rollupOptions.output.entryFileNames

I'd like to see almost no files in the "build/client/assets" folder. I guess manifest.js is okay, but my "route" files should be somewhere else (and follow the naming convention I configured in rollup.

Actual Behavior

In react-router v7, the behavior is different than remix v2. I see a bunch of files in my build/client/assets folder (manifest, route files, entry files, root files).

[markdalgleish]

Thanks for raising this issue. I've opened a PR fixing this: #13098

Also, you can control where the manifest is written via Vite's build.assetsDir option.

[skratchdot]

awesome work @markdalgleish! thanks for the prompt response, pr, and additional info about build.assetsDir option 🙌 🎉 🚀

[markdalgleish]

@skratchdot Thank you 🙏

The PR fixing this (#13098) has been merged and will be out in the next release.

[github-actions]

🤖 Hello there,

We just published version 7.3.0 which involves this issue. If you'd like to take it for a test run please try it out and let us know what you think!

Thanks!

[skratchdot]

I confirmed v7.3.0 fixes the issue for me. Thanks!

skratchdot/react-router-issue@aadf4d8