refactor: extract unit tests into separate _tests.rs files

Move inline #[cfg(test)] mod tests { ... } blocks from 22 source files
into dedicated _tests.rs companion files, wired via:

    #[cfg(test)]
    #[path = "module_tests.rs"]
    mod tests;

This keeps implementation-focused source files leaner and more scannable
while preserving full access to private items through `use super::*;`.

Modules extracted:
  core:      db, note_parser, payloads, project, references, sync_run,
             timeline_collect, timeline_expand, timeline_seed
  cli:       list (55 tests), who (75 tests)
  documents: extractor (43 tests), regenerator
  embedding: change_detector, chunking
  gitlab:    graphql (wiremock async tests), transformers/issue
  ingestion: dirty_tracker, discussions, issues, mr_diffs

Also adds conflicts_with("explain_score") to the --detail flag in the
who command to prevent mutually exclusive flags from being combined.

All 629 unit tests pass. No behavior changes.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

src/core/note_parser_tests.rs

@@ -0,0 +1,325 @@
+use super::*;
+
+#[test]
+fn test_parse_mentioned_in_mr() {
+    let refs = parse_cross_refs("mentioned in !567");
+    assert_eq!(refs.len(), 1);
+    assert_eq!(refs[0].reference_type, "mentioned");
+    assert_eq!(refs[0].target_entity_type, "merge_request");
+    assert_eq!(refs[0].target_iid, 567);
+    assert!(refs[0].target_project_path.is_none());
+}
+
+#[test]
+fn test_parse_mentioned_in_issue() {
+    let refs = parse_cross_refs("mentioned in #234");
+    assert_eq!(refs.len(), 1);
+    assert_eq!(refs[0].reference_type, "mentioned");
+    assert_eq!(refs[0].target_entity_type, "issue");
+    assert_eq!(refs[0].target_iid, 234);
+    assert!(refs[0].target_project_path.is_none());
+}
+
+#[test]
+fn test_parse_mentioned_cross_project() {
+    let refs = parse_cross_refs("mentioned in group/repo!789");
+    assert_eq!(refs.len(), 1);
+    assert_eq!(refs[0].reference_type, "mentioned");
+    assert_eq!(refs[0].target_entity_type, "merge_request");
+    assert_eq!(refs[0].target_iid, 789);
+    assert_eq!(refs[0].target_project_path.as_deref(), Some("group/repo"));
+}
+
+#[test]
+fn test_parse_mentioned_cross_project_issue() {
+    let refs = parse_cross_refs("mentioned in group/repo#123");
+    assert_eq!(refs.len(), 1);
+    assert_eq!(refs[0].reference_type, "mentioned");
+    assert_eq!(refs[0].target_entity_type, "issue");
+    assert_eq!(refs[0].target_iid, 123);
+    assert_eq!(refs[0].target_project_path.as_deref(), Some("group/repo"));
+}
+
+#[test]
+fn test_parse_closed_by_mr() {
+    let refs = parse_cross_refs("closed by !567");
+    assert_eq!(refs.len(), 1);
+    assert_eq!(refs[0].reference_type, "closes");
+    assert_eq!(refs[0].target_entity_type, "merge_request");
+    assert_eq!(refs[0].target_iid, 567);
+    assert!(refs[0].target_project_path.is_none());
+}
+
+#[test]
+fn test_parse_closed_by_cross_project() {
+    let refs = parse_cross_refs("closed by group/repo!789");
+    assert_eq!(refs.len(), 1);
+    assert_eq!(refs[0].reference_type, "closes");
+    assert_eq!(refs[0].target_entity_type, "merge_request");
+    assert_eq!(refs[0].target_iid, 789);
+    assert_eq!(refs[0].target_project_path.as_deref(), Some("group/repo"));
+}
+
+#[test]
+fn test_parse_multiple_refs() {
+    let refs = parse_cross_refs("mentioned in !123 and mentioned in #456");
+    assert_eq!(refs.len(), 2);
+    assert_eq!(refs[0].target_entity_type, "merge_request");
+    assert_eq!(refs[0].target_iid, 123);
+    assert_eq!(refs[1].target_entity_type, "issue");
+    assert_eq!(refs[1].target_iid, 456);
+}
+
+#[test]
+fn test_parse_no_refs() {
+    let refs = parse_cross_refs("Updated the description");
+    assert!(refs.is_empty());
+}
+
+#[test]
+fn test_parse_non_english_note() {
+    let refs = parse_cross_refs("a ajout\u{00e9} l'\u{00e9}tiquette ~bug");
+    assert!(refs.is_empty());
+}
+
+#[test]
+fn test_parse_multi_level_group_path() {
+    let refs = parse_cross_refs("mentioned in top/sub/project#123");
+    assert_eq!(refs.len(), 1);
+    assert_eq!(
+        refs[0].target_project_path.as_deref(),
+        Some("top/sub/project")
+    );
+    assert_eq!(refs[0].target_iid, 123);
+}
+
+#[test]
+fn test_parse_deeply_nested_group_path() {
+    let refs = parse_cross_refs("mentioned in a/b/c/d/e!42");
+    assert_eq!(refs.len(), 1);
+    assert_eq!(refs[0].target_project_path.as_deref(), Some("a/b/c/d/e"));
+    assert_eq!(refs[0].target_iid, 42);
+}
+
+#[test]
+fn test_parse_hyphenated_project_path() {
+    let refs = parse_cross_refs("mentioned in my-group/my-project#99");
+    assert_eq!(refs.len(), 1);
+    assert_eq!(
+        refs[0].target_project_path.as_deref(),
+        Some("my-group/my-project")
+    );
+}
+
+#[test]
+fn test_parse_dotted_project_path() {
+    let refs = parse_cross_refs("mentioned in visiostack.io/backend#123");
+    assert_eq!(refs.len(), 1);
+    assert_eq!(
+        refs[0].target_project_path.as_deref(),
+        Some("visiostack.io/backend")
+    );
+    assert_eq!(refs[0].target_iid, 123);
+}
+
+#[test]
+fn test_parse_dotted_nested_project_path() {
+    let refs = parse_cross_refs("closed by my.org/sub.group/my.project!42");
+    assert_eq!(refs.len(), 1);
+    assert_eq!(
+        refs[0].target_project_path.as_deref(),
+        Some("my.org/sub.group/my.project")
+    );
+    assert_eq!(refs[0].target_entity_type, "merge_request");
+    assert_eq!(refs[0].target_iid, 42);
+}
+
+#[test]
+fn test_parse_self_reference_is_valid() {
+    let refs = parse_cross_refs("mentioned in #123");
+    assert_eq!(refs.len(), 1);
+    assert_eq!(refs[0].target_iid, 123);
+}
+
+#[test]
+fn test_parse_mixed_mentioned_and_closed() {
+    let refs = parse_cross_refs("mentioned in !10 and closed by !20");
+    assert_eq!(refs.len(), 2);
+    assert_eq!(refs[0].reference_type, "mentioned");
+    assert_eq!(refs[0].target_iid, 10);
+    assert_eq!(refs[1].reference_type, "closes");
+    assert_eq!(refs[1].target_iid, 20);
+}
+
+fn setup_test_db() -> Connection {
+    use crate::core::db::{create_connection, run_migrations};
+
+    let conn = create_connection(std::path::Path::new(":memory:")).unwrap();
+    run_migrations(&conn).unwrap();
+    conn
+}
+
+fn seed_test_data(conn: &Connection) -> i64 {
+    let now = now_ms();
+
+    conn.execute(
+        "INSERT INTO projects (id, gitlab_project_id, path_with_namespace, web_url, created_at, updated_at)
+         VALUES (1, 100, 'group/test-project', 'https://gitlab.com/group/test-project', ?1, ?1)",
+        [now],
+    )
+    .unwrap();
+
+    conn.execute(
+        "INSERT INTO issues (id, gitlab_id, project_id, iid, title, state, created_at, updated_at, last_seen_at)
+         VALUES (10, 1000, 1, 123, 'Test Issue', 'opened', ?1, ?1, ?1)",
+        [now],
+    )
+    .unwrap();
+
+    conn.execute(
+        "INSERT INTO issues (id, gitlab_id, project_id, iid, title, state, created_at, updated_at, last_seen_at)
+         VALUES (11, 1001, 1, 456, 'Another Issue', 'opened', ?1, ?1, ?1)",
+        [now],
+    )
+    .unwrap();
+
+    conn.execute(
+        "INSERT INTO merge_requests (id, gitlab_id, project_id, iid, title, state, source_branch, target_branch, author_username, created_at, updated_at, last_seen_at)
+         VALUES (20, 2000, 1, 789, 'Test MR', 'opened', 'feat', 'main', 'dev', ?1, ?1, ?1)",
+        [now],
+    )
+    .unwrap();
+
+    conn.execute(
+        "INSERT INTO discussions (id, gitlab_discussion_id, project_id, issue_id, noteable_type, last_seen_at)
+         VALUES (30, 'disc-aaa', 1, 10, 'Issue', ?1)",
+        [now],
+    )
+    .unwrap();
+
+    conn.execute(
+        "INSERT INTO discussions (id, gitlab_discussion_id, project_id, merge_request_id, noteable_type, last_seen_at)
+         VALUES (31, 'disc-bbb', 1, 20, 'MergeRequest', ?1)",
+        [now],
+    )
+    .unwrap();
+
+    conn.execute(
+        "INSERT INTO notes (id, gitlab_id, discussion_id, project_id, is_system, body, created_at, updated_at, last_seen_at)
+         VALUES (40, 4000, 30, 1, 1, 'mentioned in !789', ?1, ?1, ?1)",
+        [now],
+    )
+    .unwrap();
+
+    conn.execute(
+        "INSERT INTO notes (id, gitlab_id, discussion_id, project_id, is_system, body, created_at, updated_at, last_seen_at)
+         VALUES (41, 4001, 31, 1, 1, 'mentioned in #456', ?1, ?1, ?1)",
+        [now],
+    )
+    .unwrap();
+
+    conn.execute(
+        "INSERT INTO notes (id, gitlab_id, discussion_id, project_id, is_system, body, created_at, updated_at, last_seen_at)
+         VALUES (42, 4002, 30, 1, 0, 'mentioned in !999', ?1, ?1, ?1)",
+        [now],
+    )
+    .unwrap();
+
+    conn.execute(
+        "INSERT INTO notes (id, gitlab_id, discussion_id, project_id, is_system, body, created_at, updated_at, last_seen_at)
+         VALUES (43, 4003, 30, 1, 1, 'added label ~bug', ?1, ?1, ?1)",
+        [now],
+    )
+    .unwrap();
+
+    conn.execute(
+        "INSERT INTO notes (id, gitlab_id, discussion_id, project_id, is_system, body, created_at, updated_at, last_seen_at)
+         VALUES (44, 4004, 30, 1, 1, 'mentioned in other/project#999', ?1, ?1, ?1)",
+        [now],
+    )
+    .unwrap();
+
+    1
+}
+
+#[test]
+fn test_extract_refs_from_system_notes_integration() {
+    let conn = setup_test_db();
+    let project_id = seed_test_data(&conn);
+
+    let result = extract_refs_from_system_notes(&conn, project_id).unwrap();
+
+    assert_eq!(result.inserted, 2, "Two same-project refs should resolve");
+    assert_eq!(
+        result.skipped_unresolvable, 1,
+        "One cross-project ref should be unresolvable"
+    );
+    assert_eq!(
+        result.parse_failures, 1,
+        "One system note has no cross-ref pattern"
+    );
+
+    let ref_count: i64 = conn
+        .query_row(
+            "SELECT COUNT(*) FROM entity_references WHERE project_id = ?1 AND source_method = 'note_parse'",
+            [project_id],
+            |row| row.get(0),
+        )
+        .unwrap();
+    assert_eq!(ref_count, 3, "Should have 3 entity_references rows total");
+
+    let unresolved_count: i64 = conn
+        .query_row(
+            "SELECT COUNT(*) FROM entity_references WHERE target_entity_id IS NULL AND source_method = 'note_parse'",
+            [],
+            |row| row.get(0),
+        )
+        .unwrap();
+    assert_eq!(
+        unresolved_count, 1,
+        "Should have 1 unresolved cross-project ref"
+    );
+
+    let (path, iid): (String, i64) = conn
+        .query_row(
+            "SELECT target_project_path, target_entity_iid FROM entity_references WHERE target_entity_id IS NULL",
+            [],
+            |row| Ok((row.get(0)?, row.get(1)?)),
+        )
+        .unwrap();
+    assert_eq!(path, "other/project");
+    assert_eq!(iid, 999);
+}
+
+#[test]
+fn test_extract_refs_idempotent() {
+    let conn = setup_test_db();
+    let project_id = seed_test_data(&conn);
+
+    let result1 = extract_refs_from_system_notes(&conn, project_id).unwrap();
+    let result2 = extract_refs_from_system_notes(&conn, project_id).unwrap();
+
+    assert_eq!(result2.inserted, 0);
+    assert_eq!(result2.skipped_unresolvable, 0);
+
+    let total: i64 = conn
+        .query_row(
+            "SELECT COUNT(*) FROM entity_references WHERE source_method = 'note_parse'",
+            [],
+            |row| row.get(0),
+        )
+        .unwrap();
+    assert_eq!(
+        total,
+        (result1.inserted + result1.skipped_unresolvable) as i64
+    );
+}
+
+#[test]
+fn test_extract_refs_empty_project() {
+    let conn = setup_test_db();
+    let result = extract_refs_from_system_notes(&conn, 999).unwrap();
+    assert_eq!(result.inserted, 0);
+    assert_eq!(result.skipped_unresolvable, 0);
+    assert_eq!(result.parse_failures, 0);
+}