index.html expectation regression in custom backend prod build

[sjc5]

Describe the regression

In stable vite (7.1.2), as well as in the prior version of rolldown-vite I was using (7.0.10), you could run production builds with custom backend integrations without an index.html entry module. This works perfectly and according to expectations.

In latest rolldown-vite (7.1.2), I am getting this error when attempting to run the same build:

[UNRESOLVED_ENTRY] Error: Cannot resolve entry module index.html.

Reproduction

–

Expected Behavior

Successful build.

Actual Behavior

Build fails with [UNRESOLVED_ENTRY] Error: Cannot resolve entry module index.html.

Steps to Reproduce

No response

System Info

Happens across systems, but here is my local:


System:
    OS: macOS 14.3.1
    CPU: (14) arm64 Apple M3 Max
    Memory: 75.20 MB / 36.00 GB
    Shell: 5.9 - /bin/zsh
  Binaries:
    Node: 22.11.0 - ~/.nvm/versions/node/v22.11.0/bin/node
    Yarn: 1.22.21 - /usr/local/bin/yarn
    npm: 11.4.2 - ~/.nvm/versions/node/v22.11.0/bin/npm
    pnpm: 10.10.0 - ~/.nvm/versions/node/v22.11.0/bin/pnpm
  Browsers:
    Brave Browser: 135.1.77.101
    Chrome: 138.0.7204.92
    Safari: 17.3.1
  npmPackages:
    rolldown-vite:  7.1.2

Used Package Manager

pnpm

Logs

My deepest apologies that I do not have time right now to create a minimal repro with a custom backend integration. My hope is that this rings a bell about a likely regression path. If not, no worries, and feel free to close.

Validations

• Follow our Code of Conduct
• Read the Contributing Guidelines.
• Read the docs and the Rolldown-related guide.
• Check that there isn't already an issue that reports the same regression to avoid creating a duplicate.
• Check that this is a concrete regression. For Q&A open a GitHub Discussion or join our Discord Chat Server.
• The provided reproduction is a minimal reproducible example of the regression.

[github-actions]

Hello @sjc5. Please provide a minimal reproduction using a GitHub repository or StackBlitz. Issues marked with needs reproduction will be closed if they have no activity within 3 days.

[shulaoda]

Could you try v7.1.1? In v7.1.2, we enabled native plugins by default.

[sjc5]

@shulaoda

v7.0.12 is the latest working version. All v7.1.x versions contain the regression.

[sjc5]

Also, my apologies about missing the repro. I am very swamped but figured you would prefer to have the report than nothing at all. I should be able to make an isolated repro in a few weeks if still needed.

Meanwhile, if you have Go on your system, you could:

1. run npm create river@latest
2. remove vite / add rolldown-vite
3. run npm build

It won't be particularly minimal, as it will include an entire Go-side custom backend integration -- and it runs the vite commands from the Go-side, etc. -- but wanted to mention the option in case you're willing to jump through the hoops to debug.

[hi-ogawa]

Can you get a debug log by DEBUG=vite:* npm build? Sharing that here might help instead of setting up go locally.

[sjc5]

Sure thing @hi-ogawa:

LOGS.txt

[sapphi-red]

@sjc5 This was happening because the plugin was returning both build.rollupOptions and build.rolldownOptions (build.rolldownOptions is included in c.build).
https://github.com/river-now/river/blob/c04305917fc7717cf2f52bc60c83bd75fa74a33f/internal/framework/river_build.go#L109
In that case, rolldown-vite ignores build.rollupOptions.
To fix this, you can remove the line quoted above. Vite will merge the returned config with the config passed to the config hook, so you don't have to manually merge the config.

[sjc5]

Confirming that this worked. Thank you very much @sapphi-red!