Tooling idea thread: Post ideas for things you would like to have. Could be heroku or rust specific or could be more general

[schneems]

(General) Keep a Changelog linting

We have changelog checking on GHA, but it doesn't validate the format. If we added Keep A Changelog linting it would prevent issues like https://github.com/heroku/buildpacks-ruby/pull/283/files#diff-82032714d881e3cbf53230847846645d5956738ab3ce7b30b839dac1f02fa934R10. A changelog entry is added, but it is not under an Added/Changed/Fixed header.

Possible solution(s):

• Extend the Changelog check to also validate the format and raise an error appropriately

(rust) Lint deny_unknown_fields used on all Deserialize structs

Info on the flag in heroku/buildpacks-ruby#272. It would be nice to have some way to lint/check this for Rust buildpack projects.

Possible solution(s):

• Some kind of lint to ensure all declared structs that are Deserialize also use this feature
• Documenting this caveat somewhere, such as a mdbook

(rust) Protect against logic errors for filesystem access

Problem: Some of the Rust stdlib functions can hide problems, for example https://doc.rust-lang.org/std/path/struct.Path.html#method.is_file will return false if there is a permissions error with a file. This results in confusing error messages to users because we might say something like "No such file Procfile, please add this file to your project and try again" but if they $ ls they'll see Procfile. The answer to this problem is to ensure APIs that return a Result are used instead like https://doc.rust-lang.org/std/path/struct.Path.html#method.try_exists.

Possible solution(s):

• Some kind of lint to check against using a known set of "bad" APIs and error on them.
• Documenting this caveat somewhere, such as a mdbook

Add your own ideas

Post below

[colincasey]

(General) Keep a Changelog linting

This seems like a job that https://github.com/heroku/keep_a_changelog would be well suited for. We could enhance that repo with some WASM compilation for use in a GitHub Action that handles validation and/or other checks.

(Rust) CNB semver checks

Imagine something like cargo-semver-checks but it checks rules like the ones defined in Paketo's Semantic Versioning of Buildpacks and Builders RFC against libcnb.rs-based projects.