`cargo add` takes `package.rust-version` into account when no version-req is specified
- Implementation: Consider rust-version when selecting packages for cargo add #12078
- Unstable feature:
-Zmsrv-policy
Problem
When running cargo add foo, we create a version-req out of the latest version in the index. If this has a higher rust-version, then that can break for people.
Proposed Solution
Constrain the candidate versions in the index by their rust-version being lesser or equal to the current crate's rust-version.
The main question is what to do when there are no matches due to rust-version.
- Add anyways
- Error with newest version's
rust-version
Notes
No response