Aura/crates/aura-vocabulary/tests/c28_layering.rs

//! C28 structural fitness: the node crates obey the ladder import direction.
//! The compiler only rejects import cycles; an acyclic-but-outward dependency
//! (e.g. `aura-std` -> `aura-market`) would compile silently. This test reads
//! each node crate's `[dependencies]` table and asserts its intra-workspace edges
//! stay within the inner set C28 permits for that layer. `[dev-dependencies]` are
//! C28-exempt (tests may cross layers) and are deliberately not inspected.

use std::path::PathBuf;

fn workspace_root() -> PathBuf {
    // aura-vocabulary/ + /../.. = workspace root (the repo idiom for reaching it).
    PathBuf::from(env!("CARGO_MANIFEST_DIR")).join("..").join("..")
}

/// Every `crates/*` directory that has its own `Cargo.toml` — the actual workspace
/// membership, read from disk rather than duplicated by hand, so the `allowed` table
/// below can be checked for completeness instead of silently omitting a crate.
fn workspace_crate_names() -> Vec<String> {
    let crates_dir = workspace_root().join("crates");
    let mut names: Vec<String> = std::fs::read_dir(&crates_dir)
        .unwrap_or_else(|e| panic!("read {}: {e}", crates_dir.display()))
        .filter_map(|entry| {
            let entry = entry.expect("dir entry");
            let path = entry.path();
            if path.join("Cargo.toml").is_file() {
                Some(entry.file_name().into_string().expect("utf8 dir name"))
            } else {
                None
            }
        })
        .collect();
    names.sort();
    names
}

/// The `aura-*` keys under `[dependencies]` (NOT `[dev-dependencies]`) of a crate.
fn prod_intra_workspace_deps(crate_name: &str) -> Vec<String> {
    let manifest = workspace_root()
        .join("crates")
        .join(crate_name)
        .join("Cargo.toml");
    let text = std::fs::read_to_string(&manifest)
        .unwrap_or_else(|e| panic!("read {}: {e}", manifest.display()));
    let doc: toml::Value = toml::from_str(&text).expect("Cargo.toml parses as TOML");
    match doc.get("dependencies").and_then(|d| d.as_table()) {
        Some(deps) => deps
            .keys()
            .filter(|k| k.starts_with("aura-"))
            .cloned()
            .collect(),
        None => Vec::new(),
    }
}

#[test]
fn node_crates_obey_the_c28_import_direction() {
    // (crate, the intra-workspace [dependencies] C28 permits for its layer)
    let allowed: &[(&str, &[&str])] = &[
        ("aura-core", &[]),                              // foundation: no aura-* deps
        ("aura-analysis", &[]),                          // foundation: no aura-* deps
        ("aura-measurement", &["aura-core", "aura-analysis"]),
        ("aura-std", &["aura-core"]),
        ("aura-market", &["aura-core"]),
        ("aura-strategy", &["aura-core"]),
        ("aura-engine", &["aura-core", "aura-analysis"]),
        ("aura-backtest", &["aura-core", "aura-engine"]),
        (
            "aura-vocabulary",
            &["aura-core", "aura-std", "aura-market", "aura-strategy", "aura-backtest"],
        ),
        (
            "aura-composites",
            &["aura-core", "aura-engine", "aura-std", "aura-strategy", "aura-backtest"],
        ),
        ("aura-ingest", &["aura-core", "aura-engine"]),
        ("aura-research", &["aura-core"]),
        (
            "aura-registry",
            &["aura-core", "aura-engine", "aura-backtest", "aura-analysis", "aura-research"],
        ),
        (
            "aura-campaign",
            &[
                "aura-core",
                "aura-engine",
                "aura-backtest",
                "aura-analysis",
                "aura-registry",
                "aura-research",
            ],
        ),
        (
            "aura-runner",
            &[
                "aura-core",
                "aura-engine",
                "aura-std",
                "aura-strategy",
                "aura-backtest",
                "aura-composites",
                "aura-ingest",
                "aura-registry",
                "aura-research",
                "aura-campaign",
                "aura-vocabulary",
            ],
        ),
        ("aura-bench", &["aura-core", "aura-engine", "aura-std", "aura-ingest"]),
        (
            "aura-cli",
            &[
                "aura-core",
                "aura-engine",
                "aura-std",
                "aura-strategy",
                "aura-backtest",
                "aura-registry",
                "aura-research",
                "aura-campaign",
                "aura-vocabulary",
                "aura-ingest",
                "aura-measurement",
                "aura-runner",
            ],
        ),
    ];

    let mut table_names: Vec<&str> = allowed.iter().map(|(name, _)| *name).collect();
    table_names.sort();
    let disk_names = workspace_crate_names();
    assert_eq!(
        table_names,
        disk_names.iter().map(String::as_str).collect::<Vec<_>>(),
        "C28 full-workspace: `allowed` must enumerate exactly the crates under `crates/` \
         (add the new crate's permitted set here, even a foundation crate with no aura-* \
         deps) — otherwise it escapes the C28 guard silently"
    );

    for (crate_name, permitted) in allowed {
        for dep in prod_intra_workspace_deps(crate_name) {
            assert!(
                permitted.contains(&dep.as_str()),
                "C28 import-direction violation: `{crate_name}` [dependencies] on `{dep}`, \
                 outside its permitted inner set {permitted:?}"
            );
        }
    }

    for (crate_name, permitted) in allowed {
        for shell_or_assembly in ["aura-cli", "aura-runner"] {
            let exempt = *crate_name == "aura-cli" && shell_or_assembly == "aura-runner";
            assert!(
                exempt || !permitted.contains(&shell_or_assembly),
                "C28 assembly violation: `{crate_name}`'s permitted set names \
                 `{shell_or_assembly}`, but the shell/assembly crates are imported \
                 by nothing except the shell itself"
            );
        }
    }
}

#[test]
fn the_shell_defines_no_domain_modules_and_no_lib_target() {
    let root = workspace_root();
    let manifest_text =
        std::fs::read_to_string(root.join("crates/aura-cli/Cargo.toml")).unwrap();
    let manifest: toml::Value =
        toml::from_str(&manifest_text).expect("Cargo.toml parses as TOML");
    assert!(
        manifest.get("lib").is_none(),
        "C28: the shell exports nothing — aura-cli must stay a pure binary crate"
    );
    let mut modules: Vec<String> = std::fs::read_dir(root.join("crates/aura-cli/src"))
        .unwrap()
        .map(|e| e.unwrap().file_name().into_string().unwrap())
        .collect();
    modules.sort();
    assert_eq!(
        modules,
        [
            "campaign_run.rs",
            "graph_construct.rs",
            "main.rs",
            "render.rs",
            "research_docs.rs",
            "scaffold.rs",
            "verb_sugar.rs",
        ],
        "C28 (#295): the shell holds argv/dispatch, argv->document translation, \
         and presentation only — a new module needs a library home"
    );
}