supercode-harness 0.4.4

//! TDD suite for natively loading real Claude Code and Codex session logs.
//!
//! Fixtures under `tests/fixtures/` are *real, unmodified* session JSONL files
//! copied from a developer's `~/.claude/projects` and `~/.codex/sessions`. The
//! point of supercode is to be a superset of those tools, so step one is being
//! able to load their on-disk sessions and continue them.

use std::path::{Path, PathBuf};

use supercode_harness::session::{Session, SessionSource};
use supercode_harness::{Fidelity, Role};

fn fixture(name: &str) -> PathBuf {
    Path::new(env!("CARGO_MANIFEST_DIR"))
        .join("tests/fixtures")
        .join(name)
}

fn roles(session: &Session) -> Vec<Role> {
    session.messages.iter().map(|m| m.role).collect()
}

fn total_tool_calls(session: &Session) -> usize {
    session.messages.iter().map(|m| m.tool_calls().len()).sum()
}

fn tool_messages(session: &Session) -> usize {
    session
        .messages
        .iter()
        .filter(|m| m.role == Role::Tool)
        .count()
}

// ---- Claude Code ----------------------------------------------------------

#[test]
fn loads_claude_code_metadata() {
    let s = Session::from_claude_code(fixture("claude_code_session.jsonl")).unwrap();
    assert_eq!(s.meta.source, SessionSource::ClaudeCode);
    assert_eq!(
        s.meta.session_id.as_deref(),
        Some("213bb148-51ea-453f-9206-f8b4b1168547")
    );
    assert_eq!(s.meta.model.as_deref(), Some("claude-opus-4-8"));
    assert!(
        s.meta
            .cwd
            .as_deref()
            .and_then(Path::to_str)
            .unwrap_or("")
            .ends_with("work"),
        "cwd should be recovered from the transcript"
    );
}

#[test]
fn loads_claude_code_message_sequence() {
    let s = Session::from_claude_code(fixture("claude_code_session.jsonl")).unwrap();
    // user → assistant(thinking + tool_use chunks coalesced) → tool_result →
    // assistant(text).
    //
    // The fixture's 2nd and 3rd JSONL records are genuinely SEPARATE Claude
    // assistant lines (same `parentUuid` chain, no user turn between): one
    // carries ONLY a `thinking` block, the next ONLY the `tool_use`. Before
    // the active-history fix they became two OpenAI assistant turns, the
    // first completely empty on the wire. They are chunks of one Anthropic
    // response (`message.id` matches), so replay coalesces them while keeping
    // the thinking metadata on the surviving tool-call message.
    assert_eq!(
        roles(&s),
        vec![Role::User, Role::Assistant, Role::Tool, Role::Assistant]
    );
    // Non-message lines (attachment, last-prompt, queue-operation) are skipped.
    assert_eq!(total_tool_calls(&s), 1);
    assert_eq!(tool_messages(&s), 1);
    // The first user turn has real text content.
    assert!(!s.messages[0].content.as_deref().unwrap_or("").is_empty());
    // Reasoning stays reversible metadata on the coalesced tool-use turn.
    assert!(s.messages[1].content.is_none());
    assert_eq!(s.messages[1].tool_calls().len(), 1);
    assert!(s.messages[1].metadata.contains_key("thinking"));
    // The final assistant turn is plain text, not a tool call.
    assert!(s.messages[3].tool_calls().is_empty());
    assert!(s.messages[3].content.is_some());
}

#[test]
fn claude_code_thinking_blocks_are_dropped() {
    let s = Session::from_claude_code(fixture("claude_code_session.jsonl")).unwrap();
    // A `thinking` block is never serialized verbatim into a message's
    // *content* (it has no cross-provider-replayable text slot there) —
    // PARITY-11 retains it in `metadata["thinking"]`/`["thinking_signature"]`
    // instead of vanishing entirely, but `content` itself must still never
    // carry the raw block.
    for m in &s.messages {
        let c = m.content.as_deref().unwrap_or("");
        assert!(!c.contains("\"type\":\"thinking\""));
    }
    // The fixture's thinking chunk remains inspectable on its coalesced
    // assistant response, not exposed as an empty standalone wire turn.
    assert!(
        s.messages
            .iter()
            .any(|m| m.metadata.contains_key("thinking")),
        "the fixture's standalone thinking-only turn must survive as metadata"
    );
}

fn inline_jsonl(values: Vec<serde_json::Value>) -> String {
    values
        .into_iter()
        .map(|value| serde_json::to_string(&value).unwrap())
        .collect::<Vec<_>>()
        .join("\n")
        + "\n"
}

#[test]
fn claude_resume_keeps_legacy_linear_transcripts_without_graph_ids() {
    let source = concat!(
        r#"{"type":"user","message":{"role":"user","content":"legacy prompt"}}"#,
        "\n",
        r#"{"type":"assistant","message":{"role":"assistant","content":[{"type":"text","text":"legacy answer"}]}}"#,
        "\n",
        r#"{"type":"assistant","message":{"role":"assistant","content":[{"type":"text","text":"separate legacy turn"}]}}"#,
        "\n",
    );

    let session = Session::from_claude_code_str(source).unwrap();
    assert_eq!(session.messages.len(), 3);
    assert_eq!(
        session.messages[0].content.as_deref(),
        Some("legacy prompt")
    );
    assert_eq!(
        session.messages[1].content.as_deref(),
        Some("legacy answer")
    );
    assert_eq!(
        session.messages[2].content.as_deref(),
        Some("separate legacy turn")
    );
    assert_eq!(session.raw_verbatim(), source);
}

#[test]
fn claude_resume_projects_compacted_sidechain_only_child() {
    let source = inline_jsonl(vec![
        serde_json::json!({"type":"user","uuid":"old","parentUuid":null,"isSidechain":true,"agentId":"child-1","message":{"role":"user","content":"obsolete child prefix"}}),
        serde_json::json!({"type":"system","subtype":"compact_boundary","uuid":"boundary","parentUuid":null,"isSidechain":true}),
        serde_json::json!({"type":"user","uuid":"summary","parentUuid":"boundary","isSidechain":true,"isCompactSummary":true,"message":{"role":"user","content":"child compact summary"}}),
        serde_json::json!({"type":"assistant","uuid":"answer","parentUuid":"summary","isSidechain":true,"message":{"id":"child-message","role":"assistant","content":[{"type":"text","text":"child post-compact answer"}]}}),
    ]);

    let session = Session::from_claude_code_str(&source).unwrap();
    let visible = session
        .messages
        .iter()
        .filter_map(|message| message.content.as_deref())
        .collect::<Vec<_>>()
        .join("\n");
    assert!(visible.contains("child compact summary"));
    assert!(visible.contains("child post-compact answer"));
    assert!(!visible.contains("obsolete child prefix"));
    assert_eq!(session.raw_verbatim(), source);
}

#[test]
fn claude_subagent_attachment_propagates_child_projection_failure() {
    let tmp = std::env::temp_dir().join(format!(
        "supercode-child-projection-failure-{}",
        std::process::id()
    ));
    let main_path = tmp.join("parent.jsonl");
    let subagents = tmp.join("parent/subagents");
    std::fs::create_dir_all(&subagents).unwrap();
    std::fs::write(
        &main_path,
        r#"{"type":"user","message":{"role":"user","content":"parent"}}"#,
    )
    .unwrap();
    let child_path = subagents.join("agent-broken.jsonl");
    std::fs::write(
        &child_path,
        concat!(
            r#"{"type":"user","uuid":"child-a","parentUuid":"child-b","isSidechain":true,"agentId":"broken","message":{"role":"user","content":"cycle a"}}"#,
            "\n",
            r#"{"type":"assistant","uuid":"child-b","parentUuid":"child-a","isSidechain":true,"agentId":"broken","message":{"id":"m","role":"assistant","content":[{"type":"text","text":"cycle b"}]}}"#,
        ),
    )
    .unwrap();

    let error = Session::load(&main_path).unwrap_err().to_string();
    let _ = std::fs::remove_dir_all(&tmp);
    assert!(
        error.contains("failed to reconstruct Claude subagent"),
        "{error}"
    );
    assert!(error.contains("agent-broken.jsonl"), "{error}");
    assert!(
        error.contains("cycle in active Claude parentUuid chain"),
        "{error}"
    );
}

#[test]
fn claude_resume_selects_one_parent_uuid_branch() {
    let source = inline_jsonl(vec![
        serde_json::json!({"type":"user","uuid":"u0","parentUuid":null,"message":{"role":"user","content":"root"}}),
        serde_json::json!({"type":"assistant","uuid":"a-old","parentUuid":"u0","message":{"id":"m-old","role":"assistant","content":[{"type":"text","text":"old answer"}]}}),
        serde_json::json!({"type":"user","uuid":"u-old","parentUuid":"a-old","message":{"role":"user","content":"selected old leaf"}}),
        serde_json::json!({"type":"assistant","uuid":"a-new","parentUuid":"u0","message":{"id":"m-new","role":"assistant","content":[{"type":"text","text":"new answer"}]}}),
        serde_json::json!({"type":"user","uuid":"u-new","parentUuid":"a-new","message":{"role":"user","content":"unselected new leaf"}}),
        serde_json::json!({"type":"last-prompt","leafUuid":"u-old","explicit":true}),
    ]);
    let session = Session::from_claude_code_str(&source).unwrap();
    let text = session
        .messages
        .iter()
        .filter_map(|message| message.content.as_deref())
        .collect::<Vec<_>>()
        .join("\n");
    assert!(text.contains("selected old leaf"));
    assert!(!text.contains("new answer"));
    assert!(!text.contains("unselected new leaf"));
    assert_eq!(session.raw_verbatim(), source);
}

#[test]
fn claude_resume_uses_latest_leaf_when_last_prompt_is_stale() {
    let source = inline_jsonl(vec![
        serde_json::json!({"type":"user","uuid":"u0","parentUuid":null,"message":{"role":"user","content":"root"}}),
        serde_json::json!({"type":"assistant","uuid":"a-old","parentUuid":"u0","message":{"id":"m-old","role":"assistant","content":[{"type":"text","text":"old answer"}]}}),
        serde_json::json!({"type":"last-prompt","leafUuid":"a-old"}),
        serde_json::json!({"type":"assistant","uuid":"a-new","parentUuid":"u0","message":{"id":"m-new","role":"assistant","content":[{"type":"text","text":"latest answer"}]}}),
        serde_json::json!({"type":"system","subtype":"turn_duration","uuid":"duration","parentUuid":"a-new","messageCount":2}),
    ]);
    let session = Session::from_claude_code_str(&source).unwrap();
    let text = session
        .messages
        .iter()
        .filter_map(|message| message.content.as_deref())
        .collect::<Vec<_>>()
        .join("\n");
    assert!(text.contains("latest answer"));
    assert!(!text.contains("old answer"));
}

#[test]
fn claude_resume_applies_latest_preserved_compaction() {
    let source = inline_jsonl(vec![
        serde_json::json!({"type":"user","uuid":"old","parentUuid":null,"message":{"role":"user","content":"obsolete prefix"}}),
        serde_json::json!({"type":"assistant","uuid":"keep-a","parentUuid":"old","message":{"id":"m-keep","role":"assistant","content":[{"type":"text","text":"preserved answer"}]}}),
        serde_json::json!({"type":"user","uuid":"keep-u","parentUuid":"keep-a","message":{"role":"user","content":"preserved prompt"}}),
        serde_json::json!({"type":"system","subtype":"compact_boundary","uuid":"boundary","parentUuid":null,"compactMetadata":{"preservedMessages":{"anchorUuid":"summary","uuids":["keep-a","keep-u"]}}}),
        serde_json::json!({"type":"user","uuid":"summary","parentUuid":"boundary","isCompactSummary":true,"isVisibleInTranscriptOnly":true,"message":{"role":"user","content":"latest compact summary"}}),
        serde_json::json!({"type":"assistant","uuid":"post-a","parentUuid":"keep-u","message":{"id":"m-post","role":"assistant","content":[{"type":"text","text":"post compact answer"}]}}),
        serde_json::json!({"type":"user","uuid":"post-u","parentUuid":"post-a","message":{"role":"user","content":"post compact prompt"}}),
    ]);
    let session = Session::from_claude_code_str(&source).unwrap();
    let contents: Vec<&str> = session
        .messages
        .iter()
        .filter_map(|message| message.content.as_deref())
        .collect();
    assert_eq!(
        contents,
        vec![
            "latest compact summary",
            "preserved answer",
            "preserved prompt",
            "post compact answer",
            "post compact prompt"
        ]
    );
    assert_eq!(session.raw_verbatim(), source);
}

#[test]
fn claude_resume_coalesces_streamed_assistant_chunks_and_pairs_result() {
    let source = inline_jsonl(vec![
        serde_json::json!({"type":"user","uuid":"u","parentUuid":null,"message":{"role":"user","content":"inspect"}}),
        serde_json::json!({"type":"assistant","uuid":"thinking","parentUuid":"u","message":{"id":"m","role":"assistant","content":[{"type":"thinking","thinking":"private","signature":"sig"}]}}),
        serde_json::json!({"type":"assistant","uuid":"text","parentUuid":"u","message":{"id":"m","role":"assistant","content":[{"type":"text","text":"checking"}]}}),
        serde_json::json!({"type":"assistant","uuid":"call","parentUuid":"u","message":{"id":"m","role":"assistant","content":[{"type":"tool_use","id":"tool-1","name":"Read","input":{"path":"x"}}]}}),
        serde_json::json!({"type":"user","uuid":"result","parentUuid":"call","message":{"role":"user","content":[{"type":"tool_result","tool_use_id":"tool-1","content":"ok"}]}}),
    ]);
    let session = Session::from_claude_code_str(&source).unwrap();
    assert_eq!(
        roles(&session),
        vec![Role::User, Role::Assistant, Role::Tool]
    );
    assert_eq!(session.messages[1].content.as_deref(), Some("checking"));
    assert_eq!(session.messages[1].tool_calls().len(), 1);
    assert_eq!(
        session.messages[1]
            .metadata
            .get("thinking")
            .map(String::as_str),
        Some("private")
    );
    assert_eq!(session.messages[2].tool_call_id.as_deref(), Some("tool-1"));
}

#[test]
fn claude_resume_keeps_interrupt_marker_but_excludes_api_error_carrier() {
    let source = inline_jsonl(vec![
        serde_json::json!({"type":"user","uuid":"u","parentUuid":null,"message":{"role":"user","content":"work"}}),
        serde_json::json!({"type":"assistant","uuid":"a","parentUuid":"u","message":{"id":"m","role":"assistant","content":[{"type":"text","text":"partial"}]}}),
        serde_json::json!({"type":"user","uuid":"interrupt","parentUuid":"a","interruptedMessageId":"m","message":{"role":"user","content":[{"type":"text","text":"[Request interrupted by user]"}]}}),
        serde_json::json!({"type":"assistant","uuid":"error","parentUuid":"interrupt","isApiErrorMessage":true,"error":"rate_limit","message":{"id":"error-id","role":"assistant","content":[{"type":"text","text":"weekly limit"}]}}),
        serde_json::json!({"type":"system","subtype":"turn_duration","uuid":"duration","parentUuid":"error"}),
    ]);
    let session = Session::from_claude_code_str(&source).unwrap();
    let text = session
        .messages
        .iter()
        .filter_map(|message| message.content.as_deref())
        .collect::<Vec<_>>()
        .join("\n");
    assert!(text.contains("[Request interrupted by user]"));
    assert!(!text.contains("weekly limit"));
}

#[test]
fn claude_queue_operations_do_not_duplicate_dequeued_prompt() {
    let source = inline_jsonl(vec![
        serde_json::json!({"type":"queue-operation","operation":"enqueue","content":"scheduled prompt"}),
        serde_json::json!({"type":"queue-operation","operation":"dequeue"}),
        serde_json::json!({"type":"user","uuid":"u","parentUuid":null,"message":{"role":"user","content":"scheduled prompt"}}),
    ]);
    let session = Session::from_claude_code_str(&source).unwrap();
    assert_eq!(session.messages.len(), 1);
    assert_eq!(
        session.messages[0].content.as_deref(),
        Some("scheduled prompt")
    );
    assert_eq!(session.raw_verbatim(), source);
}

/// A compacted/resumed Claude transcript whose live record points at a record
/// that is no longer on disk. Both directions are asserted here on purpose:
/// the read-only VIEW must render it, and lossless continuation must keep
/// refusing it.
fn severed_claude_transcript() -> String {
    inline_jsonl(vec![
        serde_json::json!({"type":"user","uuid":"orphan-u","parentUuid":null,"message":{"role":"user","content":"stranded prompt"}}),
        serde_json::json!({"type":"assistant","uuid":"orphan-a","parentUuid":"orphan-u","message":{"id":"m-orphan","role":"assistant","content":[{"type":"text","text":"stranded answer"}]}}),
        serde_json::json!({"type":"assistant","uuid":"live-a","parentUuid":"pruned-by-compaction","message":{"id":"m-live","role":"assistant","content":[{"type":"text","text":"live answer"}]}}),
        serde_json::json!({"type":"user","uuid":"live-u","parentUuid":"live-a","message":{"role":"user","content":"live prompt"}}),
    ])
}

#[test]
fn claude_view_stitches_a_severed_graph_and_names_the_dangling_uuid() {
    let session = Session::from_claude_code_str_with_fidelity(
        &severed_claude_transcript(),
        Fidelity::Semantic,
    )
    .unwrap();

    let contents: Vec<&str> = session
        .messages
        .iter()
        .filter_map(|message| message.content.as_deref())
        .collect();
    // The orphaned segment is retained, spliced ahead of the live one in
    // transcript order — not dropped, and not reordered.
    assert_eq!(
        contents,
        vec![
            "stranded prompt",
            "stranded answer",
            "live answer",
            "live prompt"
        ]
    );
    assert_eq!(session.load_fidelity(), Fidelity::Semantic);
    let residue = session.load_residue.join("\n");
    assert!(residue.contains("live-a"), "{residue}");
    assert!(residue.contains("pruned-by-compaction"), "{residue}");
    assert!(
        residue.contains("stitched in transcript order"),
        "{residue}"
    );
    assert_eq!(session.raw_verbatim(), severed_claude_transcript());
}

#[test]
fn claude_lossless_load_still_refuses_a_severed_graph() {
    let error = Session::from_claude_code_str(&severed_claude_transcript())
        .unwrap_err()
        .to_string();
    assert!(
        error.contains("cannot reconstruct lossless Claude continuation"),
        "{error}"
    );
    assert!(error.contains("has missing parentUuid"), "{error}");
    // Every level above `semantic` refuses; only the view degrades.
    for fidelity in [Fidelity::ByteLossless, Fidelity::ValueLossless] {
        assert!(
            Session::from_claude_code_str_with_fidelity(&severed_claude_transcript(), fidelity)
                .is_err(),
            "{fidelity:?} must not degrade"
        );
    }
}

#[test]
fn claude_view_leaves_an_intact_graph_exactly_as_lossless_load_projects_it() {
    // The view mode must not become a second, looser projection of healthy
    // transcripts: with nothing severed there is nothing to stitch, so both
    // reconstructions are identical and the view claims no residue.
    let source = inline_jsonl(vec![
        serde_json::json!({"type":"user","uuid":"u0","parentUuid":null,"message":{"role":"user","content":"root"}}),
        serde_json::json!({"type":"assistant","uuid":"a-old","parentUuid":"u0","message":{"id":"m-old","role":"assistant","content":[{"type":"text","text":"abandoned branch"}]}}),
        serde_json::json!({"type":"assistant","uuid":"a-new","parentUuid":"u0","message":{"id":"m-new","role":"assistant","content":[{"type":"text","text":"live branch"}]}}),
    ]);

    let strict = Session::from_claude_code_str(&source).unwrap();
    let view = Session::from_claude_code_str_with_fidelity(&source, Fidelity::Semantic).unwrap();

    assert_eq!(view.messages, strict.messages);
    assert!(view.load_residue.is_empty());
    assert_eq!(view.load_fidelity(), Fidelity::ByteLossless);
}

#[test]
fn claude_resume_rejects_broken_compaction_or_active_cycle() {
    let broken_compaction = inline_jsonl(vec![
        serde_json::json!({"type":"system","subtype":"compact_boundary","uuid":"boundary","parentUuid":null,"compactMetadata":{"preservedMessages":{"anchorUuid":"summary","uuids":["missing"]}}}),
        serde_json::json!({"type":"user","uuid":"summary","parentUuid":"boundary","message":{"role":"user","content":"summary"}}),
    ]);
    assert!(Session::from_claude_code_str(&broken_compaction).is_err());

    let cycle = inline_jsonl(vec![
        serde_json::json!({"type":"user","uuid":"u","parentUuid":"a","message":{"role":"user","content":"one"}}),
        serde_json::json!({"type":"assistant","uuid":"a","parentUuid":"u","message":{"id":"m","role":"assistant","content":[{"type":"text","text":"two"}]}}),
    ]);
    assert!(Session::from_claude_code_str(&cycle).is_err());
}

// ---- Codex ----------------------------------------------------------------

#[test]
fn loads_codex_metadata() {
    let s = Session::from_codex(fixture("codex_session.jsonl")).unwrap();
    assert_eq!(s.meta.source, SessionSource::Codex);
    assert_eq!(
        s.meta.session_id.as_deref(),
        Some("019df3ee-1c59-7983-9418-e5b4eff090b5")
    );
    assert_eq!(s.meta.model.as_deref(), Some("gpt-5.5"));
    assert_eq!(
        s.meta.cwd.as_deref().and_then(Path::to_str),
        Some("/private/tmp/codex-llm-test")
    );
    // Codex stores the agent's base instructions; we recover them as the
    // system prompt. (This fixture is a code-review session, so its base
    // instructions are custom review guidelines rather than the stock prompt.)
    let sp = s.meta.system_prompt.as_deref().unwrap_or("");
    assert!(sp.len() > 50, "base instructions should be recovered");
    assert!(sp.contains("Review guidelines"));
}

#[test]
fn loads_codex_message_sequence() {
    let s = Session::from_codex(fixture("codex_session.jsonl")).unwrap();
    // developer→system, two user turns, then two function_call/_output round
    // trips wrapped around reasoning (dropped), then a final assistant message.
    assert_eq!(
        roles(&s),
        vec![
            Role::System,
            Role::User,
            Role::User,
            Role::Assistant,
            Role::Tool,
            Role::Assistant,
            Role::Tool,
            Role::Assistant,
        ]
    );
    assert_eq!(total_tool_calls(&s), 2);
    assert_eq!(tool_messages(&s), 2);
}

// ---- Cross-cutting invariants & auto-detection ----------------------------

#[test]
fn autodetects_source_from_contents() {
    assert_eq!(
        Session::load(fixture("claude_code_session.jsonl"))
            .unwrap()
            .meta
            .source,
        SessionSource::ClaudeCode
    );
    assert_eq!(
        Session::load(fixture("codex_session.jsonl"))
            .unwrap()
            .meta
            .source,
        SessionSource::Codex
    );
}

#[test]
fn every_tool_result_matches_a_prior_tool_call() {
    for name in ["claude_code_session.jsonl", "codex_session.jsonl"] {
        let s = Session::load(fixture(name)).unwrap();
        let mut seen = std::collections::HashSet::new();
        for m in &s.messages {
            for tc in m.tool_calls() {
                seen.insert(tc.id.clone());
            }
            if m.role == Role::Tool {
                let id = m.tool_call_id.clone().unwrap_or_default();
                assert!(
                    seen.contains(&id),
                    "{name}: tool result {id:?} has no preceding tool call"
                );
            }
        }
    }
}

#[test]
fn loaded_sessions_are_replayable_openai_shape() {
    // A loaded session must serialize cleanly to the OpenAI chat-completions
    // wire format (that's how we hand it back to a model to continue).
    for name in ["claude_code_session.jsonl", "codex_session.jsonl"] {
        let s = Session::load(fixture(name)).unwrap();
        let json = serde_json::to_string(&s.messages).unwrap();
        assert!(json.starts_with('['));
        // Assistant tool-call turns must be immediately answerable: every
        // tool_call_id on a Tool message is a non-empty string.
        for m in &s.messages {
            if m.role == Role::Tool {
                assert!(!m.tool_call_id.as_deref().unwrap_or("").is_empty());
            }
        }
    }
}

// ---- Corpus robustness (opt-in) -------------------------------------------
//
// Run with: SUPERCODE_CORPUS=1 cargo test -- --ignored corpus
// Walks the real ~/.claude and ~/.codex logs and asserts the loaders survive
// thousands of heterogeneous, real-world session files.

#[test]
#[ignore = "requires local session corpus; set SUPERCODE_CORPUS=1"]
fn corpus_smoke() {
    if std::env::var("SUPERCODE_CORPUS").is_err() {
        panic!(
            "SUPERCODE_CORPUS not set — this corpus test asserts nothing without \
             the maintainer's local session logs; set SUPERCODE_CORPUS=1 to run it."
        );
    }
    let home = std::env::var("HOME").unwrap();
    let mut checked = 0usize;
    let mut errors = 0usize;
    let mut lossless_refusals = 0usize;
    let mut nonempty = 0usize;

    let cc = PathBuf::from(&home).join(".claude/projects");
    let cx = PathBuf::from(&home).join(".codex/sessions");

    for (dir, limit) in [(cc, 1500usize), (cx, 1500usize)] {
        for path in jsonl_files(&dir).into_iter().take(limit) {
            checked += 1;
            match Session::load(&path) {
                Ok(s) => {
                    if !s.messages.is_empty() {
                        nonempty += 1;
                    }
                }
                // A lossless load is SUPPOSED to refuse a transcript whose
                // record graph is severed — a compaction or a resume across
                // files leaves a live record pointing at a pruned parent, and
                // continuing from a guessed graph is exactly the loss this
                // tool exists to prevent. "The loaders must never error out on
                // real files" is therefore a claim about LOADABILITY, and the
                // read-only view is what has to carry it.
                Err(e) if e.to_string().contains("cannot reconstruct lossless") => {
                    lossless_refusals += 1;
                    match Session::load_with_fidelity(&path, Fidelity::Semantic) {
                        Ok(s) => {
                            assert!(
                                !s.load_residue.is_empty(),
                                "{} viewed without naming why lossless load refused it",
                                path.display()
                            );
                            if !s.messages.is_empty() {
                                nonempty += 1;
                            }
                        }
                        Err(view) => {
                            errors += 1;
                            eprintln!("view load error {}: {view}", path.display());
                        }
                    }
                }
                Err(e) => {
                    errors += 1;
                    eprintln!("load error {}: {e}", path.display());
                }
            }
        }
    }

    eprintln!(
        "corpus: checked={checked} nonempty={nonempty} errors={errors} \
         lossless_refusals_viewed={lossless_refusals}"
    );
    assert!(checked > 0, "found no session files to check");
    // The loaders must never error out on real files.
    assert_eq!(errors, 0, "{errors} files failed to load");
    // The overwhelming majority should yield an actual conversation.
    assert!(
        nonempty as f64 / checked as f64 > 0.9,
        "too many empty parses: {nonempty}/{checked}"
    );
}

fn jsonl_files(dir: &Path) -> Vec<PathBuf> {
    let mut out = Vec::new();
    let walker = ignore::WalkBuilder::new(dir)
        .standard_filters(false)
        .build();
    for entry in walker.flatten() {
        let p = entry.into_path();
        if p.extension().and_then(|e| e.to_str()) == Some("jsonl") {
            out.push(p);
        }
    }
    out
}