trustee-api 0.19.11

//! Materialization applier — the runtime APPLIES its bound profiles.
//!
//! This is the owed dispatch (scope line of the 0.18.0 enrollment release:
//! "payload logged, NOT applied" — this module closes that scope).
//!
//! For every bound profile in the materialization pull, the runtime
//! materializes the binding as a FIRST-CLASS AGENT-USER under
//! `~/.trustee/users/{user_hash(profile_id)}/` — the same per-user
//! machinery the dispatch lane already drives (overlay config, `.env`,
//! MCP loader cache). The profile IS the binding, so the binding key is
//! the user key.
//!
//! Per profile:
//! - `config/trustee.toml` — `[agent] name` (the identity's name),
//!   `[lifecycle] system_template` (the persona), `[llm] model` (the
//!   model@provider selector; honored when `[users].allow_llm_overlay`
//!   is on), plus the `[mcp]` section parsed out of the payload's
//!   `mcp_servers` content. Unparsable MCP content is skipped LOUDLY —
//!   recorded in the marker, never silently dropped.
//! - `.env` (0600) — the profile's `secrets` string parsed as KEY=VALUE
//!   lines. SECRET VALUES NEVER APPEAR IN ANY LOG LINE: the applier logs
//!   names and lengths only.
//! - `materialized.json` — a marker with the content fingerprint: a
//!   second pull with UNCHANGED content skips the rewrite (idempotent;
//!   only real changes touch disk).
//!
//! `desired_state` is recorded in the marker and logged; observed state
//! remains the runtime's REAL process health (the state-report lane owns
//! it — a materialized-but-idle process honestly reports idle).

use sha2::{Digest, Sha256};

use std::path::Path;

/// What the applier decided for ONE profile this pass.
#[derive(Debug, Clone, PartialEq)]
pub enum ProfileOutcome {
    /// Freshly written or updated this pass.
    Applied,
    /// Content unchanged (fingerprint match) — nothing touched.
    Unchanged,
    /// desired_state is not "running": NOT materialized (skip-with-record);
    /// `drained` = a previously materialized user was stripped (overlay +
    /// secrets removed, history preserved).
    Gated { desired: String, drained: bool },
    /// Could not be applied — reason is loud and per-profile.
    Failed { reason: String },
    /// v0.19.5: the profile is GONE from the pull payload entirely (deleted
    /// in THQ) — the applier reclaimed its materialization (overlay +
    /// secrets + marker removed; dir and history preserved) and its 16F
    /// dispatch entry leaves the table.
    Reclaimed,
}

/// Per-profile report entry.
#[derive(Debug, Clone)]
pub struct ProfileReport {
    pub profile_id: String,
    pub outcome: ProfileOutcome,
}

/// Outcome of one apply pass over the pull payload.
#[derive(Debug, Default, Clone)]
pub struct ApplyReport {
    pub profiles: Vec<ProfileReport>,
}

impl ApplyReport {
    pub fn applied(&self) -> impl Iterator<Item = &str> {
        self.profiles
            .iter()
            .filter(|p| p.outcome == ProfileOutcome::Applied)
            .map(|p| p.profile_id.as_str())
    }

    /// The observed_state string the state-report lane sends for this
    /// profile — the LAUNCH SEMANTICS contract (Paydar item 2, decided:
    /// option (b) refined). The ladder tells the truth per profile:
    /// - process has live sessions            → "running"
    /// - materialized, ready, not yet used    → "materialized"
    /// - desired_state gated it               → "stopped"
    /// - apply failed                         → "failed"
    pub fn observed_for(&self, profile_id: &str, busy: bool) -> String {
        let Some(p) = self.profiles.iter().find(|p| p.profile_id == profile_id) else {
            return if busy {
                "running: live session(s)".to_string()
            } else {
                "materialized: ready".to_string()
            };
        };
        match &p.outcome {
            ProfileOutcome::Applied | ProfileOutcome::Unchanged => {
                if busy {
                    "running: live session(s) in process".to_string()
                } else {
                    "materialized: ready".to_string()
                }
            }
            ProfileOutcome::Gated { desired, drained } => format!(
                "stopped: gated by desired_state ({desired}{})",
                if *drained { ", drained" } else { "" }
            ),
            ProfileOutcome::Failed { reason } => format!("failed: {reason}"),
            // Unreachable in practice: a reclaimed profile is no longer in
            // the payload, so the state-report loop never asks for it. The
            // arm keeps the match exhaustive and the contract honest.
            ProfileOutcome::Reclaimed => "deleted in THQ: reclaimed".to_string(),
        }
    }
}

/// Apply every bound profile in the pull payload, then RECLAIM orphans:
/// materialized users whose profile no longer appears in the payload
/// (deleted in THQ) get their overlay + secrets + marker removed — loud,
/// per-user, history preserved. `trustee_home` is the `~/.trustee`
/// directory. Never panics on payload shapes — every profile is
/// independent, failures are per-profile and loud.
pub fn apply_profiles(trustee_home: &Path, payload: &serde_json::Value) -> ApplyReport {
    let mut report = ApplyReport::default();
    let Some(profiles) = payload.get("profiles").and_then(|v| v.as_array()) else {
        return report;
    };
    for p in profiles {
        let Some(profile_id) = p.get("profile_id").and_then(|v| v.as_str()) else {
            continue;
        };
        let outcome = match apply_one(trustee_home, p) {
            Ok(o) => o,
            Err(reason) => ProfileOutcome::Failed { reason },
        };
        report.profiles.push(ProfileReport {
            profile_id: profile_id.to_string(),
            outcome,
        });
    }
    // v0.19.5: reconcile deletions — a profile missing from the payload was
    // deleted in THQ; its materialized home must not linger as a ghost
    // (dispatch-dispatchable, MCP-configured) binding.
    let bound: std::collections::HashSet<&str> = profiles
        .iter()
        .filter_map(|p| p.get("profile_id").and_then(|v| v.as_str()))
        .collect();
    reclaim_orphans(trustee_home, &bound, &mut report);
    report
}

/// Remove the materialization of every user whose marker proves applier
/// ownership (a fingerprint = currently materialized) but whose profile id
/// is absent from the pull payload. Overlay, `.env`, and marker are
/// removed; the directory and any session history stay. Drained markers
/// (no fingerprint) have nothing left on disk and are skipped.
fn reclaim_orphans(
    trustee_home: &Path,
    bound: &std::collections::HashSet<&str>,
    report: &mut ApplyReport,
) {
    let users_dir = trustee_home.join("users");
    let Ok(entries) = std::fs::read_dir(&users_dir) else {
        return;
    };
    for entry in entries.flatten() {
        let user_dir = entry.path();
        let marker_path = user_dir.join("materialized.json");
        let Ok(text) = std::fs::read_to_string(&marker_path) else {
            continue;
        };
        let Ok(v) = serde_json::from_str::<serde_json::Value>(&text) else {
            continue;
        };
        // Ownership proof: the marker must name a profile id AND carry a
        // fingerprint (the applier only writes fingerprints for
        // currently-materialized users). Anything else is not ours to touch.
        let Some(profile_id) = v.get("profile_id").and_then(|s| s.as_str()) else {
            continue;
        };
        if v.get("fingerprint").and_then(|f| f.as_str()).is_none() {
            continue;
        }
        if bound.contains(profile_id) {
            continue;
        }
        let _ = std::fs::remove_file(user_dir.join("config").join("trustee.toml"));
        let _ = std::fs::remove_file(user_dir.join(".env"));
        if let Err(e) = std::fs::remove_file(&marker_path) {
            tracing::warn!(
                target: "thq",
                "THQ reclaim: profile {profile_id} marker removal failed: {e}"
            );
        }
        tracing::warn!(
            target: "thq",
            "THQ reclaim: profile {profile_id} deleted in THQ — overlay, secrets and marker \n             removed (history preserved); dispatch entry leaves the table"
        );
        report.profiles.push(ProfileReport {
            profile_id: profile_id.to_string(),
            outcome: ProfileOutcome::Reclaimed,
        });
    }
}

/// THQ entity titles carry display prefixes ("Agent: Farzan") — the
/// materialized agent-user's own name strips them (the convention, ruled
/// 2026-09-14: titles keep the prefix, the user name does not). The marker
/// keeps the RAW title for traceability.
const TITLE_PREFIXES: [&str; 4] = ["Agent: ", "Identity: ", "Runtime: ", "Profile: "];

fn strip_title_prefix(title: &str) -> String {
    for p in TITLE_PREFIXES {
        if let Some(rest) = title.strip_prefix(p) {
            return rest.to_string();
        }
    }
    title.to_string()
}

/// Apply one profile. `Ok(true)` = written, `Ok(false)` = unchanged.
fn apply_one(trustee_home: &Path, p: &serde_json::Value) -> Result<ProfileOutcome, String> {
    let profile_id = p
        .get("profile_id")
        .and_then(|v| v.as_str())
        .ok_or("no profile_id")?;
    let raw_name = p
        .get("identity")
        .and_then(|i| i.get("name"))
        .and_then(|v| v.as_str())
        .unwrap_or("")
        .to_string();
    let name = strip_title_prefix(&raw_name);
    let identity_id = p
        .get("identity")
        .and_then(|i| i.get("id"))
        .and_then(|v| v.as_str())
        .unwrap_or("")
        .to_string();
    let persona = p
        .get("identity")
        .and_then(|i| i.get("persona"))
        .and_then(|v| v.as_str())
        .unwrap_or("")
        .to_string();
    let model = p.get("model").and_then(|v| v.as_str()).unwrap_or("").to_string();
    let mcp_servers = p
        .get("mcp_servers")
        .and_then(|v| v.as_str())
        .unwrap_or("")
        .to_string();
    // v0.19.5 (issue 567a0f40): the THQ-owned [mcp.credentials.*] blob rides
    // alongside mcp_servers — passed through VERBATIM, never derived or
    // defaulted (owner ruling: authentication config is deployment data).
    let mcp_credentials = p
        .get("mcp_credentials")
        .and_then(|v| v.as_str())
        .unwrap_or("")
        .to_string();
    // 0.19.6 (incident fc94aea9): the agent's dispatch identity is DECLARED
    // on the profile — a ${VAR} reference into the profile secrets plus an
    // issuer URL — and passed through VERBATIM. The identity is never
    // borrowed from MCP configuration (the 0.19.3–0.19.5 anchor selected it
    // by counting distinct `credentials` names on the servers; the issuer
    // reader took the first service-account credential it found — both
    // shape-based selections of an identity fact from an unrelated config
    // section).
    let identity_service_token = p
        .get("identity_service_token")
        .and_then(|v| v.as_str())
        .unwrap_or("")
        .to_string();
    let identity_issuer_url = p
        .get("identity_issuer_url")
        .and_then(|v| v.as_str())
        .unwrap_or("")
        .to_string();
    let secrets = p.get("secrets").and_then(|v| v.as_str()).unwrap_or("");
    let desired_state = p
        .get("desired_state")
        .and_then(|v| v.as_str())
        .unwrap_or("running")
        .to_string();

    let user_dir = trustee_home
        .join("users")
        .join(trustee_core::user_hash(profile_id));
    let marker_path = user_dir.join("materialized.json");

    // v0.19.1 (Paydar item 1): desired_state GATES the applier — whitelist
    // "running". A stopped/paused profile must not materialize-and-run:
    // fresh → skip-with-record; previously materialized → DRAIN (the
    // applier-owned overlay + secrets are removed, the dir and any history
    // stay, the marker records the drain). Flipping back to running
    // re-materializes via the fingerprint miss.
    if desired_state != "running" {
        let was_materialized = marker_path.exists();
        if was_materialized {
            let _ = std::fs::remove_file(user_dir.join("config").join("trustee.toml"));
            let _ = std::fs::remove_file(user_dir.join(".env"));
            let marker = serde_json::json!({
                "profile_id": profile_id,
                "desired_state": desired_state,
                "materialized": false,
                "drained_at": chrono::Utc::now().to_rfc3339(),
            });
            std::fs::write(
                &marker_path,
                serde_json::to_vec_pretty(&marker).map_err(|e| format!("serialize marker: {e}"))?,
            )
            .map_err(|e| format!("write marker: {e}"))?;
            tracing::warn!(
                target: "thq",
                "THQ apply: profile {profile_id} DRAINED (desired_state={desired_state}) —                  overlay and secrets removed; history preserved"
            );
            return Ok(ProfileOutcome::Gated {
                desired: desired_state,
                drained: true,
            });
        }
        tracing::info!(
            target: "thq",
            "THQ apply: profile {profile_id} GATED (desired_state={desired_state}) — not materialized"
        );
        return Ok(ProfileOutcome::Gated {
            desired: desired_state,
            drained: false,
        });
    }

    // --- build the overlay (guaranteed-valid TOML via the toml crate) ---
    let mut overlay = toml::Table::new();
    let mut agent = toml::Table::new();
    if !name.is_empty() {
        agent.insert("name".into(), toml::Value::String(name.clone()));
    }
    if !agent.is_empty() {
        overlay.insert("agent".into(), toml::Value::Table(agent));
    }
    if !persona.is_empty() {
        let mut lifecycle = toml::Table::new();
        lifecycle.insert("system_template".into(), toml::Value::String(persona.clone()));
        overlay.insert("lifecycle".into(), toml::Value::Table(lifecycle));
    }
    if !model.is_empty() {
        // model@provider selector form — applied verbatim; honored when
        // [users].allow_llm_overlay is enabled in the runtime's config.
        let mut llm = toml::Table::new();
        llm.insert("model".into(), toml::Value::String(model.clone()));
        overlay.insert("llm".into(), toml::Value::Table(llm));
    }
    // The [mcp] section rides in the payload's mcp_servers content, joined
    // by the mcp_credentials blob (v0.19.5). Parse each (standalone doc with
    // an [mcp] table, or a bare [mcp]/[[mcp.servers]]/[mcp.credentials.*]
    // fragment); anything unparsable is a LOUD per-profile skip — never a
    // silently-broken overlay for the whole process.
    let mut mcp_fragment = String::new();
    let mut mcp_table: Option<toml::Table> = None;
    if !mcp_servers.trim().is_empty() {
        match mcp_servers.parse::<toml::Table>() {
            Ok(frag) => {
                let mcp = frag.get("mcp").cloned().ok_or_else(|| {
                    "mcp_servers content parses as TOML but carries no [mcp] table".to_string()
                })?;
                let mcp = match mcp.as_table().cloned() {
                    Some(t) => t,
                    None => return Err("mcp_servers [mcp] is not a table".to_string()),
                };
                mcp_table = Some(mcp);
            }
            Err(e) => {
                return Err(format!(
                    "mcp_servers content is not valid TOML (skipped loudly): {e}"
                ));
            }
        }
    }
    if !mcp_credentials.trim().is_empty() {
        match mcp_credentials.parse::<toml::Table>() {
            Ok(frag) => {
                let mcp = frag.get("mcp").cloned().ok_or_else(|| {
                    "mcp_credentials content parses as TOML but carries no [mcp] table".to_string()
                })?;
                let mcp = match mcp.as_table().cloned() {
                    Some(t) => t,
                    None => return Err("mcp_credentials [mcp] is not a table".to_string()),
                };
                // MERGE into the servers-side table. Verbatim means verbatim:
                // a conflicting key between the two blobs is a loud per-profile
                // error, never a silent overwrite.
                let table = mcp_table.get_or_insert_with(toml::Table::new);
                for (k, v) in mcp {
                    if let Some(existing) = table.get(&k) {
                        if existing != &v {
                            return Err(format!(
                                "mcp_credentials conflicts with mcp_servers on [mcp.{k}] — refusing to silently overwrite"
                            ));
                        }
                    } else {
                        table.insert(k, v);
                    }
                }
            }
            Err(e) => {
                return Err(format!(
                    "mcp_credentials content is not valid TOML (skipped loudly): {e}"
                ));
            }
        }
    }
    if let Some(mcp) = mcp_table {
        // serialize WITH the key context so [[mcp.servers]] keeps its
        // full path (an inner-table serialization would emit bare
        // [[servers]] — a different table in the overlay)
        let mut doc = toml::Table::new();
        doc.insert("mcp".into(), toml::Value::Table(mcp));
        mcp_fragment = format!(
            "\n# [mcp] — materialized from THQ profile {profile_id}\n{}\n",
            toml::to_string_pretty(&toml::Value::Table(doc))
                .map_err(|e| format!("serialize mcp: {e}"))?
        );
    }

    // Console dispatch anchor (REVISED 0.19.6): [thq] makes the materialized
    // user a 16F dispatch target. The identity is the PROFILE-DECLARED
    // `identity_service_token` (a ${VAR} reference) copied VERBATIM — no
    // selection, no counting, no MCP lookup. The dispatch resolver strips
    // ${} and reads the per-user .env, so the anchor and the MCP credentials
    // resolve through the SAME env key. Undeclared → no anchor, LOUD (never
    // silent — the 0.19.4 zero-case logged nothing).
    if !identity_service_token.is_empty() {
        let mut thq = toml::Table::new();
        thq.insert("agent_name".into(), toml::Value::String(name.clone()));
        thq.insert("owner_id".into(), toml::Value::String(profile_id.to_string()));
        thq.insert(
            "service_token".into(),
            toml::Value::String(identity_service_token.clone()),
        );
        if !identity_issuer_url.is_empty() {
            thq.insert(
                "issuer_url".into(),
                toml::Value::String(identity_issuer_url.clone()),
            );
        }
        overlay.insert("thq".into(), toml::Value::Table(thq));
    } else {
        tracing::warn!(
            target: "thq",
            "THQ apply: profile {profile_id} declares NO identity_service_token — no [thq] dispatch anchor \n             (console dispatch off). Declare it on the profile: the ${{VAR}} reference into the profile secrets."
        );
    }
    let header = format!(
        "# Materialized by trustee from THQ — profile {profile_id}, identity {identity_id}.\n\
         # DO NOT HAND-EDIT: the next materialization pull rewrites changed content.\n"
    );
    let overlay_str = format!(
        "{header}{}\n{mcp_fragment}",
        toml::to_string_pretty(&toml::Value::Table(overlay.clone()))
            .map_err(|e| format!("serialize overlay: {e}"))?
    );

    // --- secrets → .env. Values NEVER logged — lengths/counts only. ---
    let env_str = resolve_env_text(secrets)?;

    // --- fingerprint: skip the rewrite when nothing changed ---
    let mut hasher = Sha256::new();
    hasher.update(overlay_str.as_bytes());
    hasher.update(b"\x00");
    hasher.update(env_str.as_bytes());
    let fingerprint = hex(&hasher.finalize());

    if let Ok(existing) = std::fs::read_to_string(&marker_path) {
        if let Ok(v) = serde_json::from_str::<serde_json::Value>(&existing) {
            if v.get("fingerprint").and_then(|f| f.as_str()) == Some(fingerprint.as_str()) {
                return Ok(ProfileOutcome::Unchanged); // unchanged — skip the rewrite
            }
        }
    }

    // --- write ---
    let config_dir = user_dir.join("config");
    std::fs::create_dir_all(&config_dir).map_err(|e| format!("mkdir: {e}"))?;
    #[cfg(unix)]
    {
        use std::os::unix::fs::PermissionsExt;
        let _ = std::fs::set_permissions(&user_dir, std::fs::Permissions::from_mode(0o700));
    }
    std::fs::write(config_dir.join("trustee.toml"), &overlay_str)
        .map_err(|e| format!("write overlay: {e}"))?;
    std::fs::write(user_dir.join(".env"), &env_str).map_err(|e| format!("write .env: {e}"))?;
    #[cfg(unix)]
    {
        use std::os::unix::fs::PermissionsExt;
        std::fs::set_permissions(
            user_dir.join(".env"),
            std::fs::Permissions::from_mode(0o600),
        )
        .map_err(|e| format!("chmod .env: {e}"))?;
    }

    // Secret lengths only — values never cross a log line.
    let secret_kv = env_str
        .lines()
        .filter(|l| !l.trim().is_empty() && !l.trim().starts_with('#'))
        .count();
    tracing::info!(
        target: "thq",
        "THQ apply: profile {profile_id} materialized (identity {identity_id:?}, desired={desired_state}, \
         secrets: {secret_kv} entr{}, fingerprint {fingerprint})",
        if secret_kv == 1 { "y" } else { "ies" }
    );

    let marker = serde_json::json!({
        "profile_id": profile_id,
        "identity_id": identity_id,
        "name": raw_name,
        "desired_state": desired_state,
        "fingerprint": fingerprint,
        "applied_at": chrono::Utc::now().to_rfc3339(),
        "mcp_applied": !mcp_fragment.is_empty(),
    });
    std::fs::write(
        &marker_path,
        serde_json::to_vec_pretty(&marker).map_err(|e| format!("serialize marker: {e}"))?,
    )
    .map_err(|e| format!("write marker: {e}"))?;
    Ok(ProfileOutcome::Applied)
}

/// Distinct `credentials` names referenced by an `[mcp]` table's servers —
/// the hooks a bare-value secrets string can be mapped to.
/// Resolve the profile's `secrets` string into `.env` file text.
///
/// Contract (thq profile metadata): `KEY=VALUE` lines, `#` comments
/// skipped. Two real-world shapes beyond the contract are honored rather
/// than silently dropped — the 0.19.0/0.19.1 defect: a non-KEY=VALUE
/// secrets string parsed to a header-only (effectively EMPTY) .env while
/// the rest of the materialization succeeded, so the agent dir looked
/// fine and the agent ran credential-less (owner report, 2026-09-14):
///   - a JSON object of string values → flattened to KEY=VALUE;
///   - a bare value (no `=` anywhere) → mapped to the SINGLE credential
///     name the profile's mcp_servers reference.
/// A bare value with zero or multiple distinct credential names is a
/// LOUD per-profile failure — never a silent empty .env.
/// Values are NEVER logged — only lengths/counts.
fn resolve_env_text(secrets: &str) -> Result<String, String> {
    const HEADER: &str = "# Materialized from THQ profile secrets — 0600, never logged.\n";
    let trimmed = secrets.trim();
    if trimmed.is_empty() {
        return Ok(HEADER.to_string());
    }

    // KEY=VALUE lines (the contract).
    let kv: Vec<(&str, &str)> = trimmed
        .lines()
        .filter_map(|line| {
            let line = line.trim();
            if line.is_empty() || line.starts_with('#') {
                return None;
            }
            let (k, v) = line.split_once('=')?;
            let k = k.trim();
            if k.is_empty() {
                return None;
            }
            Some((k, v.trim()))
        })
        .collect();
    if !kv.is_empty() {
        let mut out = String::from(HEADER);
        for (k, v) in kv {
            out.push_str(&format!("{k}={v}\n"));
        }
        return Ok(out);
    }

    // JSON object of string values.
    if trimmed.starts_with('{') {
        if let Ok(serde_json::Value::Object(map)) = serde_json::from_str(trimmed) {
            if !map.is_empty() && map.values().all(serde_json::Value::is_string) {
                let mut out = String::from(HEADER);
                for (k, v) in map {
                    out.push_str(&format!("{k}={}\n", v.as_str().unwrap_or_default()));
                }
                return Ok(out);
            }
        }
    }

    // Bare value (0.19.6): REJECTED, loud. The 0.19.2 heuristic mapped a
    // bare value to the single referenced credential NAME — a manufactured
    // key convention that collided with the ${VAR} references the overlay
    // declarations use (incident fc94aea9, T3). The .env key is not a
    // guessable fact: declare it as KEY=VALUE.
    Err(format!(
        "secrets is a bare value ({} chars) — rejected. The .env key must be DECLARED: \
         KEY=VALUE lines (exact-case; the key is the ${{VAR}} name the overlay references) \
         or a JSON object of keys to values",
        trimmed.len(),
    ))
}

fn hex(bytes: &[u8]) -> String {
    bytes.iter().map(|b| format!("{b:02x}")).collect()
}

#[cfg(test)]
mod tests {
    use super::*;
    use serde_json::json;

    fn tmp(tag: &str) -> std::path::PathBuf {
        let dir = std::env::temp_dir().join(format!(
            "trustee-mat-{tag}-{}",
            std::process::id()
        ));
        let _ = std::fs::remove_dir_all(&dir);
        std::fs::create_dir_all(&dir).unwrap();
        dir
    }

    fn fixture_payload(secrets: &str) -> serde_json::Value {
        json!({
            "profiles": [{
                "profile_id": "prof-1111",
                "name": "Profile: Farzan-nox",
                "desired_state": "running",
                "mcp_servers": "[mcp]\nenabled = true\n\n[[mcp.servers]]\nname = \"fame\"\nurl = \"https://fame.example\"\n",
                "model": "GLM-5.3-Flash@glm-zai",
                "secrets": secrets,
                "identity": {
                    "id": "ident-2222",
                    "name": "Agent: Farzan",
                    "agent_id": "fame-123",
                    "persona": "Be helpful, concise, Persian-friendly."
                }
            }],
            "total": 1
        })
    }

    fn user_dir(home: &Path, pid: &str) -> std::path::PathBuf {
        home.join("users").join(trustee_core::user_hash(pid))
    }

    #[test]
    fn applies_profile_to_user_home() {
        let home = tmp("apply");
        let report = apply_profiles(&home, &fixture_payload("farzan_service_account=sec-ret-1"));
        assert_eq!(
            report.profiles[0].outcome,
            ProfileOutcome::Applied
        );

        let ud = user_dir(&home, "prof-1111");
        let overlay = std::fs::read_to_string(ud.join("config").join("trustee.toml")).unwrap();
        assert!(overlay.contains("name = \"Farzan\""), "prefix stripped: {overlay}");
        assert!(
            !overlay.contains("Agent: Farzan"),
            "the [agent] name must not carry the title prefix"
        );
        assert!(
            overlay.contains("Be helpful, concise, Persian-friendly."),
            "persona applied: {overlay}"
        );
        assert!(overlay.contains("GLM-5.3-Flash@glm-zai"), "model pin applied");
        assert!(overlay.contains("[[mcp.servers]]"), "mcp fragment applied");
        assert!(overlay.contains("https://fame.example"));

        let env = std::fs::read_to_string(ud.join(".env")).unwrap();
        assert!(env.contains("farzan_service_account=sec-ret-1"));

        #[cfg(unix)]
        {
            use std::os::unix::fs::PermissionsExt;
            let mode = std::fs::metadata(ud.join(".env"))
                .unwrap()
                .permissions()
                .mode()
                & 0o777;
            assert_eq!(mode, 0o600, "secrets .env is owner-only");
        }

        let marker: serde_json::Value = serde_json::from_str(
            &std::fs::read_to_string(ud.join("materialized.json")).unwrap(),
        )
        .unwrap();
        assert_eq!(marker["profile_id"], "prof-1111");
        assert_eq!(marker["name"], "Agent: Farzan", "marker keeps the RAW title");
        assert_eq!(marker["desired_state"], "running");
        assert_eq!(marker["mcp_applied"], true);
        let _ = std::fs::remove_dir_all(&home);
    }

    #[test]
    fn second_pull_with_unchanged_content_skips_rewrite() {
        let home = tmp("idem");
        assert_eq!(apply_profiles(&home, &fixture_payload("k=v")).applied().count(), 1);
        let report = apply_profiles(&home, &fixture_payload("k=v"));
        assert_eq!(
            report.profiles[0].outcome,
            ProfileOutcome::Unchanged
        );
        let _ = std::fs::remove_dir_all(&home);
    }

    #[test]
    fn materialized_overlay_carries_thq_dispatch_anchor() {
        let home = tmp("thqanchor");
        let mut payload = fixture_payload("k=v");
        payload["profiles"][0]["mcp_servers"] = json!(
            "[mcp]\nenabled = true\n\n[[mcp.servers]]\nname = \"fame\"\nurl = \"https://fame.example\"\ncredentials = \"farzan_service_account\"\n"
        );
        payload["profiles"][0]["identity_service_token"] = json!("${FARZAN_SERVICE_ACCOUNT}");
        payload["profiles"][0]["identity_issuer_url"] =
            json!("https://idp.tanbal.ir/oauth2/openid/pdt-api");
        let report = apply_profiles(&home, &payload);
        assert!(matches!(report.profiles[0].outcome, ProfileOutcome::Applied));
        let overlay = std::fs::read_to_string(
            user_dir(&home, "prof-1111").join("config/trustee.toml"),
        )
        .unwrap();
        let table: toml::Table = overlay.parse().unwrap();
        let thq = table
            .get("thq")
            .expect("[thq] dispatch anchor missing from materialized overlay")
            .as_table()
            .unwrap();
        assert_eq!(
            thq.get("agent_name").and_then(|v| v.as_str()),
            Some("Farzan"),
            "agent_name must be the title-stripped profile name (0.19.1 naming rule)"
        );
        assert_eq!(
            thq.get("owner_id").and_then(|v| v.as_str()),
            Some("prof-1111"),
            "owner_id must be the STABLE binding id (the profile id), never a claim"
        );
        // 0.19.6: the anchor copies the DECLARED identity ${VAR} verbatim —
        // the dispatch resolver strips ${} and lands on the same env key the
        // MCP credentials reference. Never a credential NAME (0.19.4 did),
        // never an inference.
        assert_eq!(
            thq.get("service_token").and_then(|v| v.as_str()),
            Some("${FARZAN_SERVICE_ACCOUNT}"),
            "anchor service_token = the declared identity_service_token, VERBATIM"
        );
        assert_eq!(
            thq.get("issuer_url").and_then(|v| v.as_str()),
            Some("https://idp.tanbal.ir/oauth2/openid/pdt-api"),
            "anchor issuer_url = the declared identity_issuer_url, VERBATIM"
        );
    }

    #[test]
    fn undeclared_identity_means_no_anchor_and_the_inference_is_dead() {
        // 0.19.6 pin: the 0.19.4 inference (exactly one distinct credential
        // name on the servers → that credential IS the identity) is DELETED.
        // A single-credential profile with NO declaration gets NO anchor.
        let home = tmp("thqnoinfer");
        let mut payload = fixture_payload("k=v");
        payload["profiles"][0]["mcp_servers"] = json!(
            "[mcp]\nenabled = true\n\n[[mcp.servers]]\nname = \"fame\"\nurl = \"https://fame.example\"\ncredentials = \"farzan_service_account\"\n"
        );
        // NO identity_service_token declared
        let report = apply_profiles(&home, &payload);
        assert!(matches!(report.profiles[0].outcome, ProfileOutcome::Applied));
        let overlay = std::fs::read_to_string(
            user_dir(&home, "prof-1111").join("config/trustee.toml"),
        )
        .unwrap();
        assert!(
            !overlay.contains("[thq]"),
            "no declaration → no anchor. Counting server credentials must never select an identity again"
        );
    }

    #[test]
    fn multi_credential_profile_with_declared_identity_gets_anchor() {
        // 0.19.6: the owner's known-good two-credential config (identity
        // credential + a second tool credential) previously lost console
        // dispatch by the count rule. With a declaration, tool-credential
        // count is irrelevant to the anchor.
        let home = tmp("thqmulti");
        let mut payload = fixture_payload("k=v");
        payload["profiles"][0]["mcp_servers"] = json!(
            "[mcp]\nenabled = true\n\n[[mcp.servers]]\nname = \"a\"\nurl = \"https://a.example\"\ncredentials = \"cred_a\"\n\n[[mcp.servers]]\nname = \"b\"\nurl = \"https://b.example\"\ncredentials = \"cred_b\"\n"
        );
        payload["profiles"][0]["identity_service_token"] = json!("${ID_TOKEN}");
        let report = apply_profiles(&home, &payload);
        assert!(matches!(report.profiles[0].outcome, ProfileOutcome::Applied));
        let overlay = std::fs::read_to_string(
            user_dir(&home, "prof-1111").join("config/trustee.toml"),
        )
        .unwrap();
        let table: toml::Table = overlay.parse().unwrap();
        assert_eq!(
            table["thq"]["service_token"].as_str(),
            Some("${ID_TOKEN}"),
            "declared identity wins regardless of how many tool credentials exist"
        );
    }

    #[test]
    fn bare_secret_is_rejected_regardless_of_credential_count() {
        // 0.19.6: the 0.19.2 bare→credential-name mapping is DELETED — it
        // manufactured the .env key convention that collided with the ${VAR}
        // references (incident fc94aea9, T3). Bare values are rejected LOUD
        // in every shape, whatever the servers reference.
        for (tag, servers) in [
            ("none", ""),
            (
                "single",
                "[mcp]\nenabled = true\n\n[[mcp.servers]]\nname = \"fame\"\nurl = \"https://fame.example\"\ncredentials = \"farzan_service_account\"\n",
            ),
            (
                "multi",
                "[mcp]\nenabled = true\n\n[[mcp.servers]]\nname = \"a\"\nurl = \"https://a.example\"\ncredentials = \"cred_a\"\n\n[[mcp.servers]]\nname = \"b\"\nurl = \"https://b.example\"\ncredentials = \"cred_b\"\n",
            ),
        ] {
            let home = tmp(&format!("bare-reject-{tag}"));
            let mut payload = fixture_payload("eyJhbGciOiJIUzI1NiJ9.eyJzdWIiOiJmYXJ6YW4ifQ.sig");
            if !servers.is_empty() {
                payload["profiles"][0]["mcp_servers"] = json!(servers);
            }
            let report = apply_profiles(&home, &payload);
            match &report.profiles[0].outcome {
                ProfileOutcome::Failed { reason } => {
                    assert!(
                        reason.contains("bare value"),
                        "{tag}: reason must name the bare-value rejection: {reason}"
                    );
                    assert!(
                        reason.contains("KEY=VALUE"),
                        "{tag}: reason must state the required format: {reason}"
                    );
                }
                other => panic!("{tag}: expected loud failure, got {other:?}"),
            }
            assert!(
                !user_dir(&home, "prof-1111").exists(),
                "{tag}: a failed secrets resolution must not leave a half-materialized dir"
            );
        }
    }

    #[test]
    fn json_object_secrets_flatten_to_env_entries() {
        let home = tmp("jsonsec");
        let payload =
            fixture_payload(r#"{"farzan_service_account":"tok-1","other_key":"val-2"}"#);
        let report = apply_profiles(&home, &payload);
        assert!(matches!(report.profiles[0].outcome, ProfileOutcome::Applied));
        let env = std::fs::read_to_string(user_dir(&home, "prof-1111").join(".env")).unwrap();
        assert!(env.contains("farzan_service_account=tok-1\n"));
        assert!(env.contains("other_key=val-2\n"));
    }

    #[test]
    fn changed_secrets_reapply_and_rotate_env() {
        let home = tmp("rotate");
        apply_profiles(&home, &fixture_payload("k=old-value"));
        let report = apply_profiles(&home, &fixture_payload("k=new-value"));
        assert_eq!(report.profiles[0].outcome, ProfileOutcome::Applied);
        let env = std::fs::read_to_string(user_dir(&home, "prof-1111").join(".env")).unwrap();
        assert!(env.contains("k=new-value") && !env.contains("old-value"));
        let _ = std::fs::remove_dir_all(&home);
    }

    /// THE PIN: secret material must never surface in the redacted payload
    /// (the only form the pull ever logs).
    #[test]
    fn redacted_payload_never_carries_secret_values() {
        let canary = "SUPER-SECRET-JWT-canary-9f2c";
        let payload = fixture_payload(&format!("farzan_service_account={canary}"));
        let red = crate::thq_register::redact_payload(&payload);
        let rendered = format!("{red}");
        assert!(
            !rendered.contains(canary),
            "SECRETS-IN-LOGS regression: the redacted payload must not carry the canary"
        );
        assert!(rendered.contains("<redacted:"));
        assert_eq!(red["profiles"][0]["profile_id"], "prof-1111");
        assert_eq!(red["profiles"][0]["model"], "GLM-5.3-Flash@glm-zai");
    }

    #[test]
    fn unparsable_mcp_is_a_loud_per_profile_failure() {
        let home = tmp("badmcp");
        let mut payload = fixture_payload("k=v");
        payload["profiles"][0]["mcp_servers"] = json!("not toml at all {{{");
        let report = apply_profiles(&home, &payload);
        assert!(matches!(
            report.profiles[0].outcome,
            ProfileOutcome::Failed { .. }
        ));
        assert!(report.observed_for("prof-1111", false).starts_with("failed:"));
        let _ = std::fs::remove_dir_all(&home);
    }

    #[test]
    fn empty_secrets_produce_an_empty_env() {
        let home = tmp("nosecrets");
        apply_profiles(&home, &fixture_payload(""));
        let env = std::fs::read_to_string(user_dir(&home, "prof-1111").join(".env")).unwrap();
        assert!(env.lines().filter(|l| !l.starts_with('#')).count() == 0);
        let _ = std::fs::remove_dir_all(&home);
    }

    // ── v0.19.1: desired_state gating + drain ───────────────────────────

    fn gated_payload(desired: &str) -> serde_json::Value {
        let mut p = fixture_payload("k=v");
        p["profiles"][0]["desired_state"] = json!(desired);
        p
    }

    #[test]
    fn stopped_profile_is_gated_not_materialized() {
        let home = tmp("gate-fresh");
        let report = apply_profiles(&home, &gated_payload("stopped"));
        assert_eq!(
            report.profiles[0].outcome,
            ProfileOutcome::Gated { desired: "stopped".into(), drained: false }
        );
        assert!(
            !user_dir(&home, "prof-1111").exists(),
            "a gated profile must not materialize"
        );
        assert_eq!(
            report.observed_for("prof-1111", false),
            "stopped: gated by desired_state (stopped)"
        );
        let _ = std::fs::remove_dir_all(&home);
    }

    #[test]
    fn paused_profile_is_gated_too() {
        let home = tmp("gate-paused");
        let report = apply_profiles(&home, &gated_payload("paused"));
        assert!(matches!(
            report.profiles[0].outcome,
            ProfileOutcome::Gated { .. }
        ));
        let _ = std::fs::remove_dir_all(&home);
    }

    #[test]
    fn flip_running_to_stopped_drains_a_materialized_user() {
        let home = tmp("drain");
        apply_profiles(&home, &fixture_payload("k=v"));
        let ud = user_dir(&home, "prof-1111");
        assert!(ud.join("config").join("trustee.toml").exists());

        let report = apply_profiles(&home, &gated_payload("stopped"));
        assert_eq!(
            report.profiles[0].outcome,
            ProfileOutcome::Gated { desired: "stopped".into(), drained: true }
        );
        assert!(
            !ud.join("config").join("trustee.toml").exists(),
            "overlay removed on drain"
        );
        assert!(!ud.join(".env").exists(), "secrets removed on drain");
        let marker: serde_json::Value = serde_json::from_str(
            &std::fs::read_to_string(ud.join("materialized.json")).unwrap(),
        )
        .unwrap();
        assert_eq!(marker["materialized"], false);
        assert_eq!(marker["desired_state"], "stopped");

        // flip back to running → re-materializes (fingerprint miss)
        let report = apply_profiles(&home, &fixture_payload("k=v"));
        assert_eq!(report.profiles[0].outcome, ProfileOutcome::Applied);
        assert!(ud.join("config").join("trustee.toml").exists());
        let _ = std::fs::remove_dir_all(&home);
    }

    // ── launch-semantics contract (option b, refined) ───────────────────

    #[test]
    fn observed_ladder_maps_outcomes_truthfully() {
        let mut home = tmp("observed");
        let report = apply_profiles(&home, &fixture_payload("k=v"));
        // materialized + not busy → materialized (NOT "idle")
        assert_eq!(
            report.observed_for("prof-1111", false),
            "materialized: ready"
        );
        // process busy → running (the worker is active)
        assert_eq!(
            report.observed_for("prof-1111", true),
            "running: live session(s) in process"
        );
        // gated → stopped
        let gated = apply_profiles(&home, &gated_payload("stopped"));
        assert_eq!(
            gated.observed_for("prof-1111", false),
            "stopped: gated by desired_state (stopped, drained)",
            "the profile was previously materialized — the drain is part of the truth"
        );
        let _ = std::fs::remove_dir_all(&home);
        home = home; // no-op for symmetry
    }
}

#[cfg(test)]
mod v0195_credentials_tests {
    //! v0.19.5 pins (issue 567a0f40): the THQ-owned [mcp.credentials.*] blob
    //! materializes into the overlay VERBATIM (byte-equivalent semantics vs
    //! the owner's known-good config), a credentials change self-heals via
    //! the fingerprint, cross-blob conflicts fail loud, deleted profiles are
    //! reclaimed, and no-auth runtimes are untouched.

    use super::*;
    use serde_json::json;

    fn tmp(tag: &str) -> std::path::PathBuf {
        let dir = std::env::temp_dir().join(format!(
            "trustee-mat-0195-{tag}-{}",
            std::process::id()
        ));
        let _ = std::fs::remove_dir_all(&dir);
        std::fs::create_dir_all(&dir).unwrap();
        dir
    }

    const KNOWN_GOOD_CREDENTIALS: &str = "[mcp.credentials.farzan_service_account]\ntype = \"service-account\"\nservice_token = \"${FARZAN_SERVICE_ACCOUNT}\"\nissuer_url = \"https://idp.tanbal.ir/oauth2/openid/pdt-api\"\nclient_id = \"pdt-api\"\naudience = \"pdt-api\"\nscope = \"openid groups profile\"\n";

    fn payload_with_credentials(mcp_credentials: &str, secrets: &str) -> serde_json::Value {
        json!({
            "profiles": [{
                "profile_id": "prof-cred-1",
                "name": "Profile: Farzan-nox",
                "desired_state": "running",
                "mcp_servers": "[[mcp.servers]]\nname = \"fame\"\nurl = \"https://fame.example\"\ncredentials = \"farzan_service_account\"\n",
                "mcp_credentials": mcp_credentials,
                "model": "GLM-5.3-Flash@glm-zai",
                "secrets": secrets,
                "identity": {
                    "id": "ident-2222",
                    "name": "Agent: Farzan",
                    "agent_id": "fame-123",
                    "persona": "Be helpful."
                }
            }],
            "total": 1
        })
    }

    fn overlay_of(home: &Path, pid: &str) -> String {
        std::fs::read_to_string(
            home.join("users")
                .join(trustee_core::user_hash(pid))
                .join("config")
                .join("trustee.toml"),
        )
        .unwrap()
    }

    #[test]
    fn credentials_embed_verbatim_and_servers_survive() {
        let home = tmp("verbatim");
        let report = apply_profiles(
            &home,
            &payload_with_credentials(KNOWN_GOOD_CREDENTIALS, "FARZAN_SERVICE_ACCOUNT=tok-1"),
        );
        assert_eq!(report.profiles[0].outcome, ProfileOutcome::Applied);

        let overlay = overlay_of(&home, "prof-cred-1");
        // byte-shape acceptance bar (owner's known-good config)
        for line in [
            "[mcp.credentials.farzan_service_account]",
            "type = \"service-account\"",
            "service_token = \"${FARZAN_SERVICE_ACCOUNT}\"",
            "issuer_url = \"https://idp.tanbal.ir/oauth2/openid/pdt-api\"",
            "client_id = \"pdt-api\"",
            "audience = \"pdt-api\"",
            "scope = \"openid groups profile\"",
        ] {
            assert!(overlay.contains(line), "missing {line} in:\n{overlay}");
        }
        // the servers fragment survived the merge (key-context preserved)
        assert!(overlay.contains("[[mcp.servers]]"), "servers side:\n{overlay}");
        assert!(overlay.contains("credentials = \"farzan_service_account\""));
        // secrets landed
        let env = std::fs::read_to_string(
            home.join("users")
                .join(trustee_core::user_hash("prof-cred-1"))
                .join(".env"),
        )
        .unwrap();
        assert!(env.contains("FARZAN_SERVICE_ACCOUNT=tok-1"));
        let _ = std::fs::remove_dir_all(&home);
    }

    #[test]
    fn credentials_change_self_heals_via_fingerprint() {
        let home = tmp("selfheal");
        let without = apply_profiles(&home, &payload_with_credentials("", "k=v"));
        assert_eq!(without.profiles[0].outcome, ProfileOutcome::Applied);
        let with = apply_profiles(&home, &payload_with_credentials(KNOWN_GOOD_CREDENTIALS, "k=v"));
        assert_eq!(
            with.profiles[0].outcome,
            ProfileOutcome::Applied,
            "credentials addition must be a fingerprint MISS — re-materialization is the self-heal"
        );
        assert!(overlay_of(&home, "prof-cred-1").contains("[mcp.credentials.farzan_service_account]"));
        let _ = std::fs::remove_dir_all(&home);
    }

    #[test]
    fn cross_blob_conflict_fails_loud_not_silent_overwrite() {
        let home = tmp("conflict");
        let conflicting = "[mcp]\nenabled = false\n";
        let payload = payload_with_credentials(conflicting, "k=v");
        // the servers blob has no [mcp] wrapper key... give both a shared key:
        // servers with [mcp] enabled=true, credentials with enabled=false
        let mut p = payload.clone();
        p["profiles"][0]["mcp_servers"] =
            json!("[mcp]\nenabled = true\n\n[[mcp.servers]]\nname = \"fame\"\n");
        let report = apply_profiles(&home, &p);
        match &report.profiles[0].outcome {
            ProfileOutcome::Failed { reason } => {
                assert!(reason.contains("conflicts"), "loud conflict: {reason}");
            }
            other => panic!("expected Failed, got {other:?}"),
        }
        let _ = std::fs::remove_dir_all(&home);
    }

    #[test]
    fn unparsable_credentials_blob_is_a_loud_per_profile_skip() {
        let home = tmp("badtoml");
        let report = apply_profiles(
            &home,
            &payload_with_credentials("not [ valid toml <", "k=v"),
        );
        match &report.profiles[0].outcome {
            ProfileOutcome::Failed { reason } => {
                assert!(reason.contains("mcp_credentials"), "loud: {reason}");
            }
            other => panic!("expected Failed, got {other:?}"),
        }
        let _ = std::fs::remove_dir_all(&home);
    }

    #[test]
    fn no_credentials_payload_unchanged_nothing_fabricated() {
        let home = tmp("noauth");
        let report = apply_profiles(&home, &payload_with_credentials("", "k=v"));
        assert_eq!(report.profiles[0].outcome, ProfileOutcome::Applied);
        let overlay = overlay_of(&home, "prof-cred-1");
        assert!(
            !overlay.contains("mcp.credentials"),
            "empty credentials blob must fabricate nothing: {overlay}"
        );
        assert!(overlay.contains("[[mcp.servers]]"), "servers still materialize");
        let _ = std::fs::remove_dir_all(&home);
    }

    #[test]
    fn deleted_profile_is_reclaimed_from_home() {
        let home = tmp("reclaim");
        // bind two profiles
        let mut payload = payload_with_credentials(KNOWN_GOOD_CREDENTIALS, "FARZAN_SERVICE_ACCOUNT=t");
        payload["profiles"][0]["profile_id"] = json!("prof-gone");
        payload["profiles"].as_array_mut().unwrap().push(json!({
            "profile_id": "prof-stays",
            "name": "Profile: Stay",
            "desired_state": "running",
            "mcp_servers": "",
            "model": "",
            "secrets": "k=v",
            "identity": {"id": "i2", "name": "Agent: Stay", "agent_id": "f-2", "persona": "p"}
        }));
        payload["total"] = json!(2);
        apply_profiles(&home, &payload);

        // next pull: prof-gone deleted in THQ → payload carries only prof-stays
        let mut after = json!({"profiles": [payload["profiles"][1].clone()], "total": 1});
        after["profiles"][0]["profile_id"] = json!("prof-stays");
        let report = apply_profiles(&home, &after);

        let reclaimed = report
            .profiles
            .iter()
            .find(|p| p.profile_id == "prof-gone")
            .expect("reclaimed profile must be reported");
        assert_eq!(reclaimed.outcome, ProfileOutcome::Reclaimed);

        let gone_dir = home.join("users").join(trustee_core::user_hash("prof-gone"));
        assert!(!gone_dir.join("config").join("trustee.toml").exists(), "overlay removed");
        assert!(!gone_dir.join(".env").exists(), "secrets removed");
        assert!(!gone_dir.join("materialized.json").exists(), "marker removed");
        assert!(gone_dir.exists(), "the dir itself (history) is preserved");
        // the surviving profile is untouched
        assert!(overlay_of(&home, "prof-stays").contains("[agent]"), "survivor intact");
        let _ = std::fs::remove_dir_all(&home);
    }

    #[test]
    fn drained_and_foreign_markers_are_never_touched_by_reclaim() {
        let home = tmp("reclaim-safe");
        let users = home.join("users");
        // a DRAINED marker (no fingerprint): owned, but nothing left on disk
        let drained = users.join(trustee_core::user_hash("prof-drained"));
        std::fs::create_dir_all(&drained).unwrap();
        std::fs::write(
            drained.join("materialized.json"),
            json!({"profile_id": "prof-drained", "desired_state": "stopped", "materialized": false})
                .to_string(),
        )
        .unwrap();
        // a FOREIGN marker (not applier-shaped — no fingerprint, different world)
        let foreign = users.join(trustee_core::user_hash("prof-foreign"));
        std::fs::create_dir_all(&foreign).unwrap();
        std::fs::write(
            foreign.join("materialized.json"),
            json!({"profile_id": "prof-foreign"}).to_string(),
        )
        .unwrap();
        std::fs::write(foreign.join("keepme"), "not mine").unwrap();

        let report = apply_profiles(&home, &json!({"profiles": [], "total": 0}));
        assert!(
            report.profiles.iter().all(|p| p.outcome != ProfileOutcome::Reclaimed),
            "nothing reclaimable: {:?}",
            report.profiles
        );
        assert!(drained.join("materialized.json").exists(), "drained marker stays");
        assert!(foreign.join("keepme").exists(), "foreign dir untouched");
        let _ = std::fs::remove_dir_all(&home);
    }
}