Hark, Rust crate author! The battle for Rust's reputation as The Most Reliable Software Platform Ever is here, and nobody is free of responsibility. The future of Rust, dear Rustilian, is in your hands.
Join the Cargo Crusade and bring the Theory of Responsible API Evolution to the non-believers.
Cargo Crusader is a tool to help crate authors evaluate the impact of future API changes on downstream users of that crate before they are published to crates.io.
When you run
cargo-crusader from the source directory of your
published crate, Crusader asks crates.io for all of its reverse
dependencies - published crates that DEPEND ON YOU. It then
downloads each of them, and builds them: first against your crate as
currently published, then against your local work-in-progress
(i.e. the next version you are going to publish). It then reports
differences in behavior.
IMPORTANT SECURITY WARNING: This program executes arbitrary untrusted code downloaded from the Internet. You are strongly recommended to take your own sandboxing precautions before running it.
First, download and build Cargo Crusader, and put the
command in your
PATH environment variable:
$ git clone https://github.com/brson/cargo-crusader $ cd cargo-crusader $ cargo build --release $ export PATH=$PATH:`pwd`/target/release/
Now change directories to your source and run
$ cargo-crusader crusader: downloading reverse deps for hyper crusader: 10 reverse deps crusader: testing crate aloft crusader: testing crate austenite crusader: result 1 of 10, aloft 0.3.1: broken crusader: testing crate bare crusader: result 2 of 10, austenite 0.0.1: broken crusader: testing crate catapult crusader: result 3 of 10, bare 0.0.1: broken crusader: testing crate chan crusader: result 4 of 10, catapult 0.1.2: broken crusader: testing crate chatbot crusader: result 5 of 10, chan 0.1.14: passed crusader: testing crate click_and_load crusader: result 6 of 10, chatbot 0.2.2: regressed crusader: testing crate coinbaser crusader: result 7 of 10, click_and_load 0.0.1: broken crusader: testing crate doapi crusader: result 8 of 10, coinbaser 0.1.0: regressed crusader: testing crate ease crusader: result 9 of 10, doapi 0.1.0: broken crusader: result 10 of 10, ease 0.2.1: regressed passed: 1 regressed: 3 broken: 6 error: 0 full report: ./crusader-report.html
A full run will take quite a while. After its done it will print a summary, as well as produce an HTML file containing the full results, including all the compiler output for each test.
Tests result in four possible statuses: 'passed', if the reverse dependency built both before and after the upgrade; 'regressed', if it built before but not after; 'broken', if it didn't even build before upgrading; and 'error', for internal Crusader errors.
Presently Crusader will override reverse dependencies with your local revision even if the version they requested is not semver compatible with your work-in-progress. Crusader might first verify whether or not the WIP qualifies as a semver-valid upgrade.
Testing upstream as well - Crusader could ask for all the WIP branches of your dependencies and then override your build to see if upcoming changes are going to break your crate.
MIT/Apache-2.0 is the official license of both The Rust Project and The Cargo Crusade.