feat(add): Stabilize MSRV-aware version req selection by epage · Pull Request #1...

What does this PR try to resolve?

This is part of #9930 for rust-lang/rfcs#3537

This will make it easier to maintain an MSRV-compliant Cargo.toml but leaves validation up to the user as the resolver will pick newer versions.
This helps the MSRV-aware workflows enumerated in
rust-lang/rfcs#3537

How should we test and review this PR?

As for determining if this is ready for stabilization:

By stabilizing this without the MSRV-aware resolver, this could be confusing to the workflow with an MSRV-compatible lockfile.
PR #13561 at least raises awareness of that discrepancy.
In general there was interest in the RFC discussions to stabilize this ASAP, regardless of what resolver direction we went.

There is an unresolved question on differences in the resolver vs cargo add for dealing with an unset rust-version (noted in the tracking issue). However, we are only stabilizing the cargo add side which is a very light two-way door as this is a UX-focused command and not a programmatic command.

This hasn't gotten much end-user acceptance testing but, as its UX focused, that seems fine (light, two way door)

As such, this seems like it is ready to stabilize.

Additional information

ebkalderon, ede1998, sdroege, weihanglo, and joshuachp reacted with hooray emoji