feat(v3): PB-1-e — retire bootstrap_all_runtime; re-ground DB-8 via regen-clean CI gate (mechanism ii)

.github/workflows/ci.yml

@@ -210,6 +210,23 @@ jobs:
           fi
           scripts/check-test-timeout.sh /tmp/v3-test-timings.log
 
+      # PB-1-e — DB-8 fresh-compile gate at regen time. Replaces the in-tree
+      # `compile_full_bootstrap_dag()` vs committed-snapshot drift tests with a
+      # CI-side check: regen the bootstrap snapshot from authority, then assert
+      # the committed `bootstrap_*_generated.rs` files are byte-identical to a
+      # fresh compile. Any drift (hand-edit, stale regen, substrate change) fails
+      # CI here. See `docs/briefs/pb-1-e-residual-scaffold-retirement-worker.md`.
+      - name: v3 bootstrap snapshot fresh-compile gate
+        run: |
+          cargo run -p v3-compiler --bin regen_bootstrap
+          if ! git diff --exit-code -- \
+            src/v3/compiler/src/bootstrap_std_generated.rs \
+            src/v3/compiler/src/bootstrap_generated.rs \
+            src/v3/compiler/src/bootstrap_generated_without_parse_surface.rs; then
+            echo "::error::Committed bootstrap snapshot drifted from a fresh compile. Run \`cargo run -p v3-compiler --bin regen_bootstrap\` and commit the result."
+            exit 1
+          fi
+
       - name: v3 Compiler Clippy
         run: cargo clippy -p v3-compiler --all-targets -- -D warnings
 

src/v3/compiler/src/bootstrap.rs

@@ -88,38 +88,29 @@ fn declaration_name_preference_rank(file: &str) -> usize {
     }
 }
 
-// PB-1 scaffold boundary: this legacy std-only runtime bootstrap path exists
-// solely for `regen_bootstrap` and the PB-1 equivalence tests. Production
-// bootstrap MUST seed from `Dag::std_fixture_bootstrap_snapshot()`, not from a
-// fresh `load_fixtures(std_fixtures())` pass.
+// PB-1-e scaffold boundary: the runtime-parse helpers below exist solely so
+// `regen_bootstrap` can produce the committed snapshot files
+// (`bootstrap_*_generated.rs`) from the canonical `.dag` authorities.
+// Production bootstrap MUST seed from `Dag::std_fixture_bootstrap_snapshot()`
+// or `Dag::new()` directly; neither calls these helpers.
 //
-// Named dissolution trigger: delete this helper once the PB-1 drift harness no
-// longer needs to re-run the pre-snapshot std bootstrap path (for example if
-// regen/tests compare against a direct `.dag`-to-snapshot receipt without
-// reconstructing the runtime std Dag in-process).
+// In-tree DB-8 cross-check is "the committed snapshot is internally
+// consistent" (see `tests/integration/pb1_bootstrap_full_snapshot_test.rs`).
+// The fresh-parse-vs-snapshot acid test runs at regen time: CI invokes
+// `cargo run --bin regen_bootstrap` and asserts `git diff --exit-code` on
+// `src/v3/compiler/src/bootstrap_*_generated.rs` — drift between the
+// committed bytes and a fresh compile fails CI.
+//
+// Named dissolution trigger: delete these helpers once `regen_bootstrap`
+// itself is generated from a `.dag` regen-authority spec (so the fresh-parse
+// step is no longer hand-Rust). At that point the std snapshot can be
+// derived from the same authority that drives the rest of the regen registry.
 pub(crate) fn bootstrap_std_fixtures_only(dag: &mut Dag) {
     *dag = Dag::empty();
     load_fixtures(dag, std_fixtures());
     dag.populate_primitive_cache();
 }
 
-pub(crate) fn bootstrap_all_runtime(
-    dag: &mut Dag,
-    excluded_staged_paths: &[&str],
-    excluded_compiler_paths: &[&str],
-) {
-    *dag = Dag::std_fixture_bootstrap_snapshot();
-    // The std snapshot already represents `load_fixtures(std_fixtures())`
-    // after one `resolve_pending_identifiers` + `populate_primitive_cache`
-    // pass. Loading staged/spec/compiler fixtures on top re-runs both
-    // operations for the *combined* bootstrap Dag. That double-pass shape is
-    // intentional and must stay idempotent: the first pass closes the frozen
-    // std snapshot, the second closes cross-authority references introduced by
-    // `src/v3/std/*.dag`, `src/v3/spec/*.dag`, and `src/v3/compiler/*.dag`
-    // (while still tolerating dangling bootstrap-range stubs such as `Tuple`).
-    load_runtime_bootstrap_authorities(dag, excluded_staged_paths, excluded_compiler_paths);
-}
-
 pub(crate) fn bootstrap_runtime_authorities_on(
     dag: &mut Dag,
     excluded_staged_paths: &[&str],

src/v3/compiler/src/lib.rs

@@ -1162,11 +1162,11 @@ pub fn patch_lower_helpers_generated_type_alias_refinement(src: &str) -> String
     out
 }
 
-/// PB-1 scaffold helper: re-run the pre-snapshot std bootstrap path for
-/// `regen_bootstrap` and the PB-1 drift tests only. This is NOT a second
-/// production bootstrap authority; `Dag::new()` seeds from the committed
-/// generated snapshot. Dissolution trigger: same as
-/// `bootstrap::bootstrap_std_fixtures_only`.
+/// PB-1-e scaffold helper: fresh-parse the std fixtures so `regen_bootstrap`
+/// can produce `bootstrap_std_generated.rs` from authority. Not a production
+/// bootstrap path — `Dag::new()` seeds from the committed snapshot. Sole
+/// in-tree consumer is `regen_bootstrap`; CI's `regen_bootstrap` + `git diff`
+/// step is the cross-check that the snapshot matches a fresh compile.
 pub fn compile_std_bootstrap_dag() -> Dag {
     let mut dag = Dag::empty();
     bootstrap::bootstrap_std_fixtures_only(&mut dag);
@@ -1179,10 +1179,10 @@ pub fn generated_std_bootstrap_dag() -> Dag {
     Dag::std_fixture_bootstrap_snapshot()
 }
 
-/// PB-1 closure scaffold helper for `regen_bootstrap`: layer the staged/spec/
-/// compiler bootstrap authorities onto an explicitly supplied std seed so all
-/// generated outputs in one regen pass derive from the same `dsl/std/*.dag`
-/// authority. This is not a production bootstrap entry point.
+/// PB-1-e regen-only scaffold helper: layer the staged/spec/compiler bootstrap
+/// authorities onto an explicitly supplied std seed so all generated outputs in
+/// one regen pass derive from the same `dsl/std/*.dag` authority. Sole consumer
+/// is `regen_bootstrap`; not a production bootstrap entry point.
 pub fn compile_full_bootstrap_dag_from_std_seed(std_seed: Dag) -> Dag {
     let mut dag = std_seed;
     bootstrap::bootstrap_runtime_authorities_on(&mut dag, &[], &[]);
@@ -1198,18 +1198,6 @@ pub fn compile_full_bootstrap_without_parse_surface_dag_from_std_seed(std_seed:
     dag
 }
 
-pub fn compile_full_bootstrap_dag() -> Dag {
-    let mut dag = Dag::empty();
-    bootstrap::bootstrap_all_runtime(&mut dag, &[], &[]);
-    dag
-}
-
-pub fn compile_full_bootstrap_without_parse_surface_dag() -> Dag {
-    let mut dag = Dag::empty();
-    bootstrap::bootstrap_all_runtime(&mut dag, &["src/v3/std/parse_surface.dag"], &[]);
-    dag
-}
-
 pub fn generated_full_bootstrap_dag() -> Dag {
     Dag::new()
 }

src/v3/compiler/tests/integration.rs

@@ -111,8 +111,6 @@ mod m2_substrate_inhabitance_test;
 mod p0_std_render_repeat_string_test;
 #[path = "integration/pb1_bootstrap_full_snapshot_test.rs"]
 mod pb1_bootstrap_full_snapshot_test;
-#[path = "integration/pb1_bootstrap_std_snapshot_test.rs"]
-mod pb1_bootstrap_std_snapshot_test;
 #[path = "integration/pipe_desugar.rs"]
 mod pipe_desugar;
 #[path = "integration/r1_manual_claim_gate_test.rs"]

src/v3/compiler/tests/integration/pb1_bootstrap_full_snapshot_test.rs

@@ -1,37 +1,18 @@
 //! **Layer:** integration
+//!
+//! PB-1-e — in-tree DB-8 cross-check is now "the committed bootstrap snapshot is
+//! internally consistent": `Dag::new()` is diagnostic-clean and byte-stable across
+//! clones, and the std-only snapshot is a strict prefix-shape of the full snapshot.
+//! The fresh-parse-vs-snapshot acid test runs at regen time (`regen_bootstrap` +
+//! CI's `git diff --exit-code` on the committed `bootstrap_*_generated.rs`),
+//! not on every `cargo test`. See `docs/briefs/pb-1-e-residual-scaffold-retirement-worker.md`.
 
 use v3_compiler::{
-    compile_full_bootstrap_dag, compile_full_bootstrap_without_parse_surface_dag,
-    generated_full_bootstrap_dag, generated_full_bootstrap_without_parse_surface_dag,
-    generated_std_bootstrap_dag,
+    generated_full_bootstrap_dag, generated_std_bootstrap_dag,
     serialize::{first_difference, serialize_dag},
     Dag,
 };
 
-fn assert_no_bootstrap_drift(label: &str, runtime: &Dag, generated: &Dag) {
-    if let Some(diff) = first_difference(runtime, generated) {
-        panic!("{label} drifted from runtime bootstrap: {}", diff.detail);
-    }
-}
-
-#[test]
-fn generated_full_bootstrap_snapshot_matches_runtime_full_bootstrap() {
-    let runtime = compile_full_bootstrap_dag();
-    let generated = generated_full_bootstrap_dag();
-    assert_no_bootstrap_drift("generated full bootstrap", &runtime, &generated);
-}
-
-#[test]
-fn generated_full_bootstrap_without_parse_surface_matches_runtime_variant() {
-    let runtime = compile_full_bootstrap_without_parse_surface_dag();
-    let generated = generated_full_bootstrap_without_parse_surface_dag();
-    assert_no_bootstrap_drift(
-        "generated no-runtime-mirrors bootstrap",
-        &runtime,
-        &generated,
-    );
-}
-
 #[test]
 fn full_bootstrap_extends_std_snapshot() {
     let std_only = generated_std_bootstrap_dag();

src/v3/compiler/tests/integration/sg0_census_test.rs

@@ -239,7 +239,6 @@ const EXPECTED_HAND_AUTHORED_TEST: &[&str] = &[
     "src/v3/compiler/tests/integration/m2_substrate_inhabitance_test.rs",
     "src/v3/compiler/tests/integration/p0_std_render_repeat_string_test.rs",
     "src/v3/compiler/tests/integration/pb1_bootstrap_full_snapshot_test.rs",
-    "src/v3/compiler/tests/integration/pb1_bootstrap_std_snapshot_test.rs",
     "src/v3/compiler/tests/integration/pipe_desugar.rs",
     "src/v3/compiler/tests/integration/r1_manual_claim_gate_test.rs",
     "src/v3/compiler/tests/integration/sg0_census_test.rs",