Add a dev label for nightly releases

[andfoy]

Checklist

• Used a fork of the feedstock to propose changes
• Bumped the build number (if the version is unchanged)
• Reset the build number to 0 (if the version changed)
• Re-rendered with the latest conda-smithy (Use the phrase @conda-forge-admin, please rerender in a comment in this PR for automated rerendering)
• Ensured the license file is being packaged.

Fixes #31

This PR enables conda-forge to build nightly versions of Rust, however, this PR must be merged against a new branch dev according to CFEP-05. I would appreciate if any @conda-forge/rust maintainers could help creating that branch

[pkgw]

Thanks for tackling this. Updates to the dev branch would have to occur manually, correct?

I don't suppose there's a way to point to date-coded nightly tarballs, is there? The builds are failing because the cryptographic digests of the tarballs have changed, which is going to be a perennial annoyance (but not a showstopper) if we have to point to ever-changing rust-nightly-* tarballs.

[conda-forge-linter]

Hi! This is the friendly automated conda-forge-linting service.

I just wanted to let you know that I linted all conda-recipes in your PR (recipe) and found it was in an excellent condition.

[andfoy]

I don't suppose there's a way to point to date-coded nightly tarballs, is there? The builds are failing because the cryptographic digests of the tarballs have changed, which is going to be a perennial annoyance (but not a showstopper) if we have to point to ever-changing rust-nightly-* tarballs.

We could download date-specific tarballs using the specific URLs pinpointed by https://github.com/rust-lang/rust-forge/blob/master/src/infra/channel-layout.md

[andfoy]

I could do that, if you agree

[andfoy]

Thanks for tackling this. Updates to the dev branch would have to occur manually, correct?

I think so

[pkgw]

@andfoy If the date-specific tarballs don't mess up any other aspects of the build pipeline, I think it would be much better to point the feedstock at them.

Relatedly, can we munge the nightly date code into the package build field so that people can easily see which version they're using?

[andfoy]

@andfoy If the date-specific tarballs don't mess up any other aspects of the build pipeline, I think it would be much better to point the feedstock at them.

Sure! I'll update the recipe to point to the nightly of today

Relatedly, can we munge the nightly date code into the package build field so that people can easily see which version they're using?

I think we can set the version to highlight the date, let me see more about in the conda-forge documentation

[andfoy]

I think we could encode the date as <rust_version>. dev year month day

[andfoy]

@pkgw I think that the versioning did work indeed

[pkgw]

I have created a new dev branch equal to this branch, added a rerender commit, and retargeted this PR against the new branch. We can merge once CI passes.

[andfoy]

Thanks! @pkgw