How to specify Cargo always use nightly version?

[SoonIter]

How are you running Renovate?

A Mend.io-hosted app

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No response

Please tell us more about your question or problem

I have known that renovate won't read rust-toolchain by default, but there are still problems when using nightly features

#24870 (comment)
web-infra-dev/rspack#8611 (comment)

Command failed: cargo update --config net.git-fetch-with-cli=true --manifest-path Cargo.toml --workspace
error: failed to parse manifest at `/tmp/renovate/repos/github/web-infra-dev/rspack/Cargo.toml`

Caused by:
  the cargo feature `trim-paths` requires a nightly version of Cargo, but this is the `stable` channel
  See https://doc.rust-lang.org/book/appendix-07-nightly-rust.html for more information about Rust release channels.
  See https://doc.rust-lang.org/cargo/reference/unstable.html#profile-trim-paths-option for more information about using this feature.

Is there any way to config constraint now?

Logs (if relevant)

No response

[github-actions[bot]]

Hi there,

We need more information about your environment.

Please explain in detail how you are running Renovate. For example:

• Are you running via an official Renovate image, or using the Renovate npm package?
• Which exact image tag are you running?
• Which config/parameters are you using when running the image?
• Which config are you using in your CI/CD pipeline, if relevant?

Thanks, the Renovate team

[viceice]

needs:

• rust: support nightly channel containerbase/base#3752

[Kobzol]

As a workaround, you could try to specify RUSTC_BOOTSTRAP=1 to simulate a nightly cargo, if the corresponding feature is old enough:

"env": {
    "RUSTC_BOOTSTRAP": "1"
}

I didn't find how to modify allowedEnv though, as I'm using the Renovatebot GitHub app, and this doesn't work by default.

[rarkins]

We'll try to get nightly support in containerbase soon so that workarounds aren't necessary

[Kobzol]

Is it possible to allow custom environment variables in the Mend-hosted Renovatebot deployment? It would be a more general solution for us than just allowing nightly Cargo.

[rarkins]

Yes. Which specific ones or patterns are needed?

[Kobzol]

RUSTC_BOOTSTRAP (Kobzol/rust@0c79797), to support unstable features even with stable cargo.

[rarkins]

#33347

[RahulGautamSingh]

Please, create a new discussion.