Testing & Coverage

Running tests

# All workspace tests (no Chrome required)
cargo test --workspace

# All features including browser integration tests
cargo test --workspace --all-features

# Run only the tests that need Chrome (previously ignored)
cargo test --workspace --all-features -- --include-ignored

# Specific crate
cargo test -p stygian-graph
cargo test -p stygian-browser

Test organisation

stygian-graph

Tests live alongside their module in src/ (unit tests) and in crates/stygian-graph/tests/ (integration tests).

All tests in the graph crate pass without any external services.

stygian-browser

Browser tests fall into two categories:

To run integration tests locally:

# Ensure Chrome 120+ is on PATH, then:
cargo test -p stygian-browser --all-features -- --include-ignored

Coverage

Coverage is measured with cargo-tarpaulin.

Install

cargo install cargo-tarpaulin

Measure

# Workspace summary (excludes Chrome-gated tests)
cargo tarpaulin --workspace --all-features --ignore-tests --out Lcov

# stygian-graph only
cargo tarpaulin -p stygian-graph --all-features --ignore-tests --out Lcov

# stygian-browser logic-only (no Chrome)
cargo tarpaulin -p stygian-browser --lib --ignore-tests --out Lcov

Current numbers

High-coverage modules in stygian-graph:

Why browser coverage is bounded

Every test that launches a real Chrome instance is annotated:

#![allow(unused)]
fn main() {
#[tokio::test]
#[ignore = "requires Chrome"]
async fn pool_acquire_release() {
    // ...
}
}

This keeps cargo test fast and green in CI environments without a Chrome binary. Pure-logic coverage (fingerprint generation, stealth script math, config validation, simulator algorithms) is high; only the CDP I/O paths are excluded.

Adding tests

Unit test pattern (graph)

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

    #[tokio::test]
    async fn my_adapter_returns_error_on_empty_url() {
        let adapter = MyAdapter::default();
        let result  = adapter.execute(ServiceInput::default()).await;
        assert!(result.is_err());
    }
}
}

Browser test pattern (logic only)

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

    #[test]
    fn stealth_level_debug_display() {
        assert_eq!(format!("{:?}", StealthLevel::Advanced), "Advanced");
    }

    #[tokio::test]
    #[ignore = "requires Chrome"]
    async fn pool_warm_start() {
        let pool = BrowserPool::new(BrowserConfig::default()).await.unwrap();
        assert!(pool.stats().available >= 1);
        pool.shutdown().await;
    }
}
}

CI test matrix

The GitHub Actions CI workflow (.github/workflows/ci.yml) runs:

Browser integration tests (--include-ignored) are not run in CI — they require a Chrome binary and a display server which are not available in the default runner images.