docs(r3): audit CI slow-test exemptions

ROADMAP.md

@@ -411,7 +411,7 @@ Tracked debt not dispatched with the 2026-04-21 lane wave (Lane 1e P3.0, SG-2c-4
   - **Lane E-I — port `SubValueRelation` + inductive fields + cost algebra (M)**: port Tier 1 (structural) + Tier 2 (lattice) + Tier 3 (`CostBound` + master theorem). Requires E-T, E-C. Pre-flight: verify v3 lowers `CostBound`'s self-referential-through-`List` shape. Acceptance: carrier types ported with round-trip tests; no lens row moves on E-I alone because consumer-visible facts still wait for E-P producer/consumer wiring.
   - **Lane E-P — per-call descent-evidence provenance (M)**: first P-c side-table producer slice has landed as `v3_compiler::dag::per_call_descent_evidence` (recursive self-call / arithmetic descent; unproven edges fail closed; `TransformNode` stays unwidened). v2 stores this class of fact on `ExprCall.descent_evidence` (`src/v2/00_core.dag:199`); v3 derives it off-substrate for now. Requires E-T, E-C, E-I. Remaining acceptance: cost/complexity lenses consume the side table, plus a v2-oracle-vs-v3 cementing test against `expr_call_descent_evidence`; carrier parity for `cost.dag` / `complexity.dag` on the non-method-dispatch slice closes there.
   - **Lane E-M — `MethodSemantics` port-or-subsume (S–M)**: **closed via M-b structural subsumption.** Transitive facts (`CollectionSizeEffect` / `CostShape` / `AlgebraFieldTemplate`) remain algebra-declaration facts; v3 method-like calls dispatch through `TransformTarget::{Callable, FieldProject, Operator}` and typed declaration/effect metadata. No `src/v3/std/method_semantics.dag`, no Rust mirror, and no `ExprMethodCall` attachment point.
-- **CI ratchet architecture — PARTIAL (T-Receipts W1 second bundle)**: surfaced during the 2026-04-21 reflective analysis (`53b3110..ae8825a` range). Commits `37cd6128`, `4898983e`, `f84ed355` hardened the ratchet against CI-log instability, but `2d8396df` widened the exemption list. `scripts/slow-test-exemptions.txt` currently has 43 active non-comment exemptions (83 total file lines in the original brief included comments). **Landed partial:** `scripts/check-test-timeout.sh` now has a meta-ratchet floor of 43 active exemptions, and [docs/debt/ci-ratchet-exemption-audit-2026-04-24.md](docs/debt/ci-ratchet-exemption-audit-2026-04-24.md) classifies every current exemption from the existing annotated reasons. **Still open:** fresh CI-shaped timing audit, stale exemption deletion if any entries measure under 2s, and per-exempt duration budgets once fresh timings exist. Dispatch brief: `docs/briefs/ci-ratchet-architecture-audit.md`.
+- **CI ratchet architecture — PARTIAL (T-Receipts W1 second bundle)**: surfaced during the 2026-04-21 reflective analysis (`53b3110..ae8825a` range). Commits `37cd6128`, `4898983e`, `f84ed355` hardened the ratchet against CI-log instability, but `2d8396df` widened the exemption list. `scripts/slow-test-exemptions.txt` currently has **39** active non-comment exemptions; `scripts/check-test-timeout.sh` meta-ratchet default `TEST_TIMEOUT_MAX_EXEMPTIONS` matches that count. **Landed partial:** classification audit [docs/debt/ci-ratchet-exemption-audit-2026-04-24.md](docs/debt/ci-ratchet-exemption-audit-2026-04-24.md) (2026-04-24 baseline) plus follow-up routing audit [docs/debt/ci-ratchet-exemption-audit-2026-05-02.md](docs/debt/ci-ratchet-exemption-audit-2026-05-02.md) (bounded scope — not a completed Phase 1 per-test timing pass). **Still open:** fresh CI-shaped per-test timing audit, stale exemption deletion if any entries measure under 2s, and per-exempt duration budgets once fresh timings exist. Dispatch brief: `docs/briefs/ci-ratchet-architecture-audit.md`.
 - **`IntegrationRsScan` / `integration_rs_active_line_contains` in `src/v3/compiler/tests/integration/common/mod.rs` is a latent source of byte-constant workarounds in downstream tests** (T-Receipts, surfaced by T-Demo #686). The scanner is "deliberately narrow" and does not model Rust character literals, so any test author touching a file in its scan path cannot write `b'\\'` / `b'"'` directly and must substitute numeric byte constants (e.g., `92` / `34`) instead. Historical evidence: #686's text-slicing helper introduced `DAG_ESCAPE_BYTE` / `DAG_QUOTE_BYTE` constants for exactly this reason; #705 deleted the helper when `TestRunner::run_suite` obsoleted it, and the constants went with it — so there is **no surviving in-tree instance of the workaround today**. The scanner constraint itself remains, which means the next test author landing in the scan path will recreate the pattern. Dissolution: either widen the scanner to model Rust char literals, or replace its scan with a structural reader that doesn't need to exclude char-literal syntax. Small scope; cosmetic for now, but the constraint is a workaround attractor. Owner: unassigned; P2 Boundary Discipline / T-Receipts bundle.
 - **Stale-receipt sweep in `docs/briefs/` — PARTIAL (T-Receipts W1).** The cited `DeclarationLookup` cleanup brief now carries a historical-receipt banner stating the lane is closed by SG-4b-1-fix and that `DeclarationLookup` / `find_declaration` are gone from `src/v3/lenses/variant_payload.dag`; its stale INVARIANTS refs were also updated to stable anchors. Remaining broad `docs/briefs/` sweep stays open for later post-wave stale claims. **Include:** `docs/design-pure-bootstrap.md`'s hand-maintained count ("78 hand-maintained .rs files") was stale vs. the SG-0 census — **CLOSED in this R1 PR**: all five occurrences (lines 7, 49, 82, 105, 242 of the design doc) now point at the live census, reframed as deltas against the illustrative 78-file baseline, or scoped to the non-test + TESTING residual framing. No frozen absolute count remains.
 - **Compiler–`std/` consolidation program — specific migrations**: end-state defined in [docs/thesis/compiler-std-consolidation.md](docs/thesis/compiler-std-consolidation.md). Each of the migrations below is a standalone lane; together they collapse the compiler-specific type surface toward the positive definition (pipeline + regen + lens-specific return-type carriers + accessor). **Ratchet:** count of `type` declarations in `src/v3/compiler/*.dag` AND `src/v3/lenses/*.dag` that are NOT in the positive-def set AND NOT exempted → 0. Positive-def: pipeline/regen types + lens-API return carriers (`Origin`, `UnusedParameter`, `VariantPayloadShapeLookup` 3-variant, `TemplateArgumentBinding` semantic carrier, etc.). Exempted: `parse_tables.dag` (7 types, pending SG-2c-proper per-row classification). In-ratchet: **workaround-shaped infer-helper coproducts with named dissolution triggers (`TemplateArgumentsMatch`, `TemplateArgumentCursor`, `NormalizedInstantiationArgs`)** — Lookup-pattern carriers on lens surfaces import `v3.std.lookup::Lookup` (`complexity`, `cost`, `infer_helpers`). Primary count: 3. See thesis doc table for per-file disposition.

docs/debt/ci-ratchet-exemption-audit-2026-05-02.md

@@ -0,0 +1,101 @@
+# CI Ratchet Exemption Audit — 2026-05-02
+
+**Source:** `scripts/slow-test-exemptions.txt` and `scripts/check-test-timeout.sh` (workspace snapshot **2026-05-02**). For provenance after merge to `main`, use the commit that last touched this file (`git log -1 --format=%H -- docs/debt/ci-ratchet-exemption-audit-2026-05-02.md`); PR branch names are dispatch metadata only.
+
+**Authority:** `TESTING.md` § test layers (`feedback_test_timeout_2s`, 2000 ms per `#[test]` wall-clock); `docs/briefs/ci-ratchet-architecture-audit.md` Phase 1 shape; prior pass [ci-ratchet-exemption-audit-2026-04-24.md](ci-ratchet-exemption-audit-2026-04-24.md).
+
+**R3 dispatch parent:** [r3-debt-paydown-ledger-2026-05-02.md](r3-debt-paydown-ledger-2026-05-02.md) highest-leverage target **#10** (CI slow-test exemption fresh audit).
+
+## Summary
+
+| Metric | Value |
+|--------|------:|
+| Active exemptions (non-comment lines) | **39** |
+| `TEST_TIMEOUT_MAX_EXEMPTIONS` default in `scripts/check-test-timeout.sh` | **39** (must match; same PR rule for floor changes) |
+| Stale exemptions removed in **this** PR | **0** — no row deleted without a fresh `cargo test … -- -Z unstable-options --report-time` observation proving **≤ 2000 ms** for that test under the ratchet’s parsing rules |
+| Per-exempt duration budgets enforced in CI | **Not landed** — still deferred to Phase 2 in the architecture brief (would require parser/script extension; do not invent budgets) |
+
+**Scope (read this first):** This PR is a **bounded routing / scope audit** over the current exemption list and `check-test-timeout.sh` floor — categories, owners, STOP+PING, and explicit follow-ups. It is **not** a completed **Phase 1** pass from `docs/briefs/ci-ratchet-architecture-audit.md` (that phase expects per-test wall-clock re-measurement and stale-row deletion where proven `≤ 2000 ms`). No stale exemptions were removed here because no row was re-proven under the 2s authority in this pass.
+
+## Measurement status (honest scope)
+
+- **This pass did not re-time every exempt test.** A cold `cargo test -p v3-compiler` single-filter invocation was started for spot-checking; it did not complete within the agent window (integration binary link dominates before libtest prints timings). **All rows below are therefore categorized from the in-file ROADMAP / lane annotations, not from fresh 2026-05-02 wall-clock rows.**
+- **Follow-up (mechanical):** Re-use the CI job’s tee’d libtest log (same shape `scripts/check-test-timeout.sh` parses) or run `RUSTC_BOOTSTRAP=1 cargo test -p v3-compiler -- -Z unstable-options --report-time` once on a warmed target, extract per-name `elapsed_ms`, mark each exemption **measured / under budget / still over budget**, then delete only lines with `elapsed_ms ≤ 2000` and lower `TEST_TIMEOUT_MAX_EXEMPTIONS` in the same commit. Optionally add comment-only budget columns after that pass (still requires brief/script agreement before CI enforcement).
+
+## Delta vs 2026-04-24 audit
+
+The April audit recorded **43** active exemptions and a floor of **43**. The tree under audit now has **39** exemptions and default floor **39**. **Arithmetic is intentional:** five tokens listed below were **removed** from the exemption list on `main` between 2026-04-24 and this snapshot, and **one** new token was **added** (`r1c_e_emit_gates_dag_test::…`). Net change: **5 − 1 = −4** rows (43 → 39); that net is already reflected in `check-test-timeout.sh` before this document landed.
+
+**Rows present in 2026-04-24 audit but absent now** (retired from the exemption list elsewhere; this audit does not re-claim credit):
+
+| Exemption token (removed since April audit) |
+|---|
+| `pb1_bootstrap_full_snapshot_test::generated_full_bootstrap_snapshot_matches_runtime_full_bootstrap` |
+| `pb1_bootstrap_full_snapshot_test::generated_full_bootstrap_without_parse_surface_matches_runtime_variant` |
+| `pb1_bootstrap_std_snapshot_test::generated_std_bootstrap_snapshot_matches_runtime_std_bootstrap` |
+| `sg2_parse_authority_test::parse_generated_module_matches_checked_in_snapshot` |
+| `sg3_lower_authority_test::lower_generated_module_matches_regen_snapshot` |
+
+**New since April audit**
+
+| Exemption | Note |
+|-----------|------|
+| `r1c_e_emit_gates_dag_test::r1c_e_emit_gates_suite_passes_through_runner` | Runner/harness edge; comment cites ~2166 ms on PR #1233; paydown: R1C-E shared setup / runner lane. |
+
+## Category rubric
+
+| Code | Meaning |
+|------|---------|
+| **P** | Paydown backlog — slow for known test-shape reasons; shrink via shared setup, cache warming, harness decomposition, or lane work named in the exemption comment. |
+| **S** | Structural for now — intentional multi-emit / matrix / corpus work tied to DB-8 determinism lane until a cheaper equivalent exists. |
+| **U** | Unknown / unmeasured this pass — owner path is documented in-file; wall-clock **not** re-verified 2026-05-02. |
+
+## Category totals (from annotations; all **U** for wall-clock)
+
+| Category | Count | Notes |
+|----------|------:|-------|
+| **P** | 31 | Includes M0/M1/M2/PB/R1C-E/P0/SG/KF-1/bootstrap paydown classes. |
+| **S** | 8 | `db8_rust_emit_avoids_time_paths_and_float_hooks_on_program_matrix` + six `emit_matrix_*_is_deterministic` + `four_fixture_disk_sources_emit_deterministically`. |
+
+## STOP+PING check (`ci-ratchet-architecture-audit.md`)
+
+- **“Most exemptions structurally necessary”:** **No.** Eight lines are the DB-8 determinism matrix + four-fixture **disk** determinism row; the remainder are **P** (compile/snapshot/rustc-harness/M0/M1/M2/PB/SG/KF-1 paydown classes). This does **not** indicate the 2s budget is wrong for the whole architecture; it indicates concentrated compile-oracle debt plus one very hot P0 oracle row (`p0_std_render…`, comment still cites ~29.7 s historical observation).
+- **Parser / script invasiveness:** **No change** to exemption line format or `check-test-timeout.sh` parsing in this PR.
+
+## Exemption table (39 tests; compact ranges)
+
+| # | Exemption(s) | Cat | Paydown / routing |
+|---|----------------|-----|-------------------|
+| 1 | `bootstrap::tests::malformed_pipeline_stage_attaches_diagnostic` | P | Bootstrap fixture / test-infra caching; not TM-0. |
+| 2 | `db8_rust_emit_avoids_time_paths_and_float_hooks_on_program_matrix` | S | DB-8 Lane 3 Stage 3c / determinism matrix; 5× re-emit by design. |
+| 3–8 | Six `emit_matrix_{module,program}_{go,python,rust}_is_deterministic` | S | DB-8 module/program re-emit matrix. |
+| 9 | `four_fixture_disk_sources_emit_deterministically` | S | Four-fixture disk corpus determinism. |
+| 10 | `four_fixture_regression_test::four_fixture_suite_shares_one_reachability_shape` | P | Shared `compile_to_dag` warming / pressure-corpus paydown. |
+| 11 | `common::cached_compile::tests::cached_compile_any_returns_clean_dag_when_key_warmed_by_strict` | P | TESTING.md “Mocks over compile”; real compile remains. |
+| 12–14 | `lane2_stage_2d_symbolic_cost_test::{branch_reports_constant_when_both_arms_constant,cost_dag_compiles_cleanly,cost_generated_module_matches_checked_in_snapshot}` | P | Lane 2 Stage 2d; shared bootstrap / snapshot + rustfmt paydown. |
+| 15–16 | `m0_acceptance::{compile_boundary_is_fail_closed,post_sweep_port_state_matches_diagnostic_table}` | P | M0 acceptance compile-boundary shared setup. |
+| 17 | `m1_substrate_test::referenced_port_walk_real_helper_stack_compiles` | P | SG-3f helper-stack compile; parse/lower cutover. |
+| 18–23 | Six `m1_3_emit_rust_test::rustc_roundtrip_*` / `rustc_roundtrip_generic_list_fold_prints_one` | P | SG-7 rustc harness + emitter lane. |
+| 24–26 | `m2_lens_cost_migration_test::{complexity_dag_compiles_cleanly,complexity_dag_runs_end_to_end_via_rustc_harness,complexity_generated_module_matches_checked_in_snapshot}` | P | Lens migration harness paydown. |
+| 27 | `m2_lens_idempotency_migration_test::idempotency_emitted_analyze_matches_oracle` | P | Lane 2 Stage 2b oracle. |
+| 28 | `m2_lens_provenance_migration_test::lens_provenance_dag_runs_end_to_end_via_rustc_harness` | P | Lens harness paydown. |
+| 29–30 | `m2_lens_unused_parameters_migration_test::{unused_parameters_dag_runs_end_to_end_via_rustc_harness,unused_parameters_dag_self_analysis_reports_zero_findings}` | P | Lens harness paydown. |
+| 31 | `pb1_bootstrap_full_snapshot_test::full_bootstrap_extends_std_snapshot` | P | PB-1 snapshot compare; shared compile warming. |
+| 32 | `r1c_e_emit_gates_dag_test::r1c_e_emit_gates_suite_passes_through_runner` | P | R1C-E runner harness; shared-setup work. |
+| 33 | `bootstrap::tests::kernel_bool_path_a_attaches_diagnostic_when_boolean_algebra_unresolvable` | P | Bool kernel Path A; bridge dissolution + shared `Dag::new` warming. |
+| 34 | `p0_std_render_repeat_string_test::std_render_repeat_string_and_indent_text_match_interpreter` | P | P0 / v2 oracle; shared v2-oracle bootstrap cache (`OnceLock<ResolvedPipelineResult>` or TM-0 lane). |
+| 35 | `sg1_tokenize_authority_test::tokenize_generated_module_matches_checked_in_snapshot` | P | SG-1 tokenize snapshot lane. |
+| 36 | `sg2_parse_authority_test::parse_surface_dag_compiles_cleanly_for_regen_parse` | P | SG-2 parse surface compile; exemption comment still names removed sibling test — tidy comment in a follow-up if confusing. |
+| 37 | `sg2c1_parse_tables_authority_test::parse_tables_generated_module_matches_checked_in_snapshot` | P | SG-2c-1 parse-tables snapshot. |
+| 38 | `sg6_hand_authored_census_test::sg6_regen_lens_cli_smoke_regenerates_named_entry_without_drift` | P | SG-6 CLI subprocess smoke. |
+| 39 | `thesis_validation_test::kf_1_structural_list_operation_ordering_holds` | P | KF-1 thesis validation decomposition (TESTING.md). |
+
+The compact table’s ranges expand to **39** test tokens — the same count as non-comment lines in `scripts/slow-test-exemptions.txt` and the `TEST_TIMEOUT_MAX_EXEMPTIONS` default.
+
+## R3 per-PR debt receipt (this PR)
+
+- **Disposition:** **Debt found + routed** (bounded **scope / routing** audit — not a completed Phase 1 per-test timing audit).
+- **Debt addressed (partial):** ROADMAP bullet *CI ratchet architecture — PARTIAL* — fresh audit artifact documents the current **39**-exemption floor and routes remaining work (measured timing pass, optional per-exempt budgets).
+- **Debt found (routed):** No exemptions proven stale under the 2s authority in this pass; mechanical re-timing from CI or warmed local `cargo test` logs remains the next executable slice.
+- **Dissolved debt rows:** None — no line removed from `scripts/slow-test-exemptions.txt` without a ≤2000 ms proof.
+- **Documentation:** Stale ROADMAP counts **43**/**43** → **39**/**39** aligned with `check-test-timeout.sh` (same PR as this audit).