Testing

Three levels, from fastest to most thorough.

1. A single step’s real logic

A #[container] body is ordinary Rust, so the fastest test is just a plain #[test] calling the function directly — no harness, no infra.

For the step as it actually runs in-pod (its image, the injected bootstrap, ATHENA_PARAM_* env, host!/artifact ports), use cargo athena container emulate — docker/podman locally, exactly as Argo would, with the deployed binary pulled from S3:

cargo athena container emulate my-crate-transform -a data=hi -a factor=2

See the CLI page for --build (local binary) and the Kubernetes-context limitations.

2. Guard the generated workflow

cargo athena emit is deterministic, so snapshot it and fail CI on an unintended change — catching DAG/wiring regressions before a cluster ever sees them:

cargo athena emit --package my-workflows > expected.yaml   # commit this
# in CI:
diff <(cargo athena emit --package my-workflows) expected.yaml

(cargo-athena’s own test suite does exactly this with checked-in expected YAML across a broad “all features” fixture, plus trybuild compile-fail tests pinning the strict #[workflow] contract and the macro guards — cargo test in the repo.)

3. End-to-end on real Argo

Register the templates and submit on any real Argo + S3 (see Getting Started step 4) and assert the run Succeeded.

Conformance is not a claim: every push to main runs the project’s example workflow against a live Argo + MinIO per supported version and asserts success — see Supported Argo Versions. The repo’s scripts/{deploy,e2e-test,teardown}.sh reproduce that locally (a Docker/Podman daemon required; nix develop provides kind/argo/mc if you use Nix).