Testing Strategy

Four Levels

Level 1: Unit Tests (in-module)

Located in #[cfg(test)] modules within source files. Test critical paths: config deserialization, state machines, drift computation, serialization roundtrips.

#![allow(unused)]
fn main() {
#[cfg(test)]
mod tests {
    use super::*;

    #[test]
    fn drift_magnitude_zero_when_no_drift() { ... }
}
}

Level 2: Integration Tests (crate-level)

Located in crates/*/tests/. Use builders from pact-test-harness for setup.

#![allow(unused)]
fn main() {
use pact_test_harness::fixtures::ConfigEntryBuilder;

#[tokio::test]
async fn config_entry_roundtrip() {
    let entry = ConfigEntryBuilder::new()
        .vcluster("ml-training")
        .author("admin@example.org")
        .build();
    // ...
}
}

Level 3: BDD Acceptance Tests (`pact-acceptance`)

584 scenarios across 32 feature files using the cucumber crate. Covers all bounded contexts: boot config streaming, drift detection → commit/rollback, shell session lifecycle, emergency mode, enrollment, RBAC, policy evaluation, overlay management, partition resilience, identity mapping, workload integration, node management delegation, and 22 cross-context integration scenarios.

Runs on all platforms — uses real domain logic (JournalState, DriftEvaluator, CommitWindowManager, PactSupervisor) but stubs OS-level interactions.

Level 4: E2E Container Tests (`pact-e2e`)

Integration tests using testcontainers with real services:

Raft cluster: 3-node in-process cluster (consensus, failover, replication)
OPA: Real Rego policy evaluation via OPA container
Keycloak: Real OAuth2/OIDC flows (discovery, credentials, password, refresh, JWKS)
Loki: Structured event forwarding
Prometheus: Metrics scraping
SPIRE: Identity cascade and SVID acquisition
Linux privileged: Real cgroup/namespace tests (requires root)
Full CLI E2E: All CLI commands against real journal + agent gRPC

Level 5: Fidelity & Adversary Sweeps

Automated quality assessment (not runtime tests):

Fidelity sweep: measures assertion depth per scenario (THOROUGH/MODERATE/SHALLOW/STUB)
Adversary sweep: systematic security review across attack surfaces
Results in specs/fidelity/ and specs/findings/

Cross-Platform Testing Strategy

Three tiers matching the development model:

macOS (local dev): Unit tests + BDD acceptance + e2e containers (Docker). Feature-gated Linux-only code compiles as stubs. Mocks (MockGpuBackend, MockCpuBackend, etc.) simulate hardware detection for testing.
CI (GitHub Actions): 4-stage pipeline: fmt/clippy/deny → feature checks → test/BDD/e2e/linux-privileged → coverage. Runs on Linux runners.
Devcontainer (Linux): Full integration + acceptance + chaos tests. Real PactSupervisor with cgroup v2, real eBPF probes, real PTY allocation. BDD/cucumber scenarios run here. CI uses this for release gates.

Test Infrastructure

pact-test-harness

Shared crate (publish = false) providing:

Fixtures: ConfigEntryBuilder, ServiceDeclBuilder — fluent builders
Mocks: MockJournalClient, MockPolicyEngine, MockSupervisor, MockObserver, MockGpuBackend — Arc<Mutex<Vec<MockCall>>> for call recording

Conventions

Unit tests: #[test] or #[tokio::test]
Slow tests: marked #[ignore], run with just test-all
Feature-gated tests: #[cfg(feature = "ebpf")] etc.
Linux-only tests: #[cfg(target_os = "linux")]
All mocks use async_trait and record calls for assertions
Property tests with proptest for type invariants
Coverage target: >= 80% per crate

CI Pipeline

On every commit:
  cargo fmt --check
  cargo clippy --all-targets
  cargo nextest run (Level 1 + Level 2)
  cargo deny check

On release:
  All levels must pass (including devcontainer Level 3 + Level 4)
  Coverage report → codecov

Running Tests

just test          # Fast: unit + integration (skips #[ignore])
just test-all      # Full: includes slow tests
just test-slow     # Only slow tests
just test-linux    # Linux-only tests (in devcontainer)
just test-accept   # BDD acceptance tests (in devcontainer)

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