cargo-const

cargo-const is a command-line tool for analyzing crate compatibility in Rust projects. It helps you find versions of a crate that are compatible with your project's dependencies by inspecting the Cargo.lock file.

What it does

• Find versions of a crate compatible with your project's dependencies.
• Limit the number of results or list all found versions.
• Filter versions by maximum supported Rust version.

Installation

Install via Cargo:

cargo install cargo-const

Commands

compat

Finds compatible versions of a crate based on your project's dependencies.

Arguments

• dependency – The crate to check for compatibility (required).

Flags

• -v, --verbose – Enable verbose logging.
• -i, --include-yanked – Include yanked versions in the results.
• -c, --count <COUNT> – Number of versions to list. Can be a number or "all" (default: 5).
• -p, --path <PATH> – Path to your Cargo.lock file (default: Cargo.lock).
• -m, --max-version <VERSION> – Maximum Rust version supported by the crate.

Example

Find all compatible versions of the indexmap crate with verbose logging enabled:

user:~$ cargo-const compat indexmap --count all --verbose
Info: Cache successfully created at "/home/user/.local/share/cargo-const-0.2.0/dependencies/toml_edit/0.23.7"
Info: Cache successfully created at "/home/user/.local/share/cargo-const-0.2.0/versions/indexmap"
Compatible versions found:

2.12.0   min-rust-version = 1.82
2.11.4   min-rust-version = 1.63

Implementation Notes

• Fetches all crate information from the project's Cargo.lock.
• Determines compatible versions by combining dependency bounds; in cases where multiple unrelated dependents impose disjoint constraints, this may incorrectly conclude that no compatible versions exist (i.e., it may treat resolvable scenarios as unsatisfiable).

Contributing

Contributions are welcome! Fork the repository, make your changes, and open a pull request.

License

MIT License