base64ct: feature `edition2024` is required

[t3hnar]

Looks like this commit broke stuff on our side

Can you please advise on the best way to fix this?

error: failed to download `base64ct v1.7.0`

Caused by:
  unable to get packages from source

Caused by:
  feature `edition2024` is required

[leonardoalt]

Same here. You can pin base64ct = "=1.6.0" in your outermost workspace/package.

[tarcieri]

Yes, MSRV has been bumped to Rust 1.85. If you're unable to upgrade to Rust 1.85, you need to pin the version in Cargo.toml.

[t3hnar]

something weird is going on here, we do not have base64ct in dependency tree

[tarcieri]

To make a more specific statement here:

We painstakingly maintain MSRV compatibility for several years, however edition bumps are a time when users of crates need to expect a coordinated MSRV bump across the entire ecosystem.

We are doing a 2024 edition upgrade across all of our crates. I'm sorry if that causes inconvenience, but you can expect that more and more crates you use are going to start requiring the 2024 edition soon.

As was called out in our MSRV policy, we called out MSRV as not being part of our SemVer policy, and going forward we plan on more liberally raising MSRV now that there is an MSRV-aware resolver.

The MSRV-aware resolver should make these sorts of upgrades less painful going forward, but we can't get there without having an MSRV bump first.

[t3hnar]

@tarcieri thx

[tarcieri]

tl;dr: of how to work around this:

• for bin crates: pin to base64ct v1.6.0, ideally with a comment like "remove this when MSRV is 1.85 or above"
• for lib crates: create a Cargo.lock.msrv or thereabouts where all of your dependencies have been resolved with compatibility for your supported MSRV. You can use the MSRV aware resolver to select compatible versions

[jvff]

Would it make sense to release version 2.0.0 with the MSRV bump? That could avoid breaking semver compatibility with the old MSRV, especially if the crate is used indirectly.

[tarcieri]

It's something we could potentially consider, yes, although our SemVer policy with respect to MSRV was the following:

We may change the MSRV in the future, but it will be accompanied by a minor version bump.