From 991566b1edfafd56769f2d6e685e7ad495a1cbd1 Mon Sep 17 00:00:00 2001
From: bitfathers94 <237535319+bitfathers94@users.noreply.github.com>
Date: Sun, 26 Jul 2026 00:15:10 +0000
Subject: [PATCH] fix(engine): guard the guardrail engine and
 gate-advisory/predicted-gate files themselves
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ENGINE_DECISION_GUARDRAIL_GLOBS listed the host/engine shim pairs for
autonomy.ts and guardrail-config.ts, but never the packages/loopover-engine
files that actually decide a PR's disposition: change-guardrail.ts (the glob
matcher powering isGuardrailHit/guardrailPathMatches), gate-advisory.ts (the
gate-decision core and check-run sanitizer), and predicted-gate.ts (the
orchestrator wiring both). A PR weakening the matcher, flipping a
block/advisory disposition, or rewiring the orchestrator would not itself trip
the hard guardrail — a self-referential blind spot in the exact mechanism
meant to catch that class of change.

Add all three engine-side paths and cover each with a test asserting
isGuardrailHit trips against resolveHardGuardrailGlobs(null).

Closes #8698
---
 .../src/review/guardrail-config.ts            |  8 ++++++
 test/unit/guardrail-config.test.ts            | 25 +++++++++++++++++++
 2 files changed, 33 insertions(+)

diff --git a/packages/loopover-engine/src/review/guardrail-config.ts b/packages/loopover-engine/src/review/guardrail-config.ts
index 1277463b6d..57dd22b721 100644
--- a/packages/loopover-engine/src/review/guardrail-config.ts
+++ b/packages/loopover-engine/src/review/guardrail-config.ts
@@ -51,6 +51,14 @@ export const ENGINE_DECISION_GUARDRAIL_GLOBS = [
   "src/review/cutover-gate.ts",
   "src/review/linked-issue-hard-rules.ts",
   "src/review/outcomes-wire.ts",
+  // #8698: the guardrail-matching engine and the gate-decision core themselves were a self-referential blind
+  // spot -- none of the packages/loopover-engine files that actually decide a PR's disposition were listed, so
+  // a PR weakening the glob matcher, flipping a block/advisory disposition, or rewiring the orchestrator would
+  // not itself trip the hard guardrail. Listed on the engine side (no src/ shim exists for these) for the same
+  // reason the autonomy/guardrail-config real paths are: it is the substantive logic a PR edit would change.
+  "packages/loopover-engine/src/signals/change-guardrail.ts",
+  "packages/loopover-engine/src/advisory/gate-advisory.ts",
+  "packages/loopover-engine/src/predicted-gate.ts",
 ];
 
 // Default, safe-by-default invariant set (restored by #3943 after the original pure-config-as-code design
diff --git a/test/unit/guardrail-config.test.ts b/test/unit/guardrail-config.test.ts
index febe8a3b6c..d5a838c47a 100644
--- a/test/unit/guardrail-config.test.ts
+++ b/test/unit/guardrail-config.test.ts
@@ -37,6 +37,31 @@ describe("ENGINE_DECISION_GUARDRAIL_GLOBS — post-#6203-migration real paths (#
   });
 });
 
+// #8698: the guardrail-matching engine itself (change-guardrail.ts), the gate-decision advisory core
+// (gate-advisory.ts), and the predicted-gate orchestrator were never listed -- a self-referential blind spot,
+// since a PR weakening exactly those files would not itself trip the hard guardrail. Each must now be a hit.
+describe("ENGINE_DECISION_GUARDRAIL_GLOBS — guardrail engine + gate-advisory/predicted-gate self-protection (#8698)", () => {
+  it("lists the guardrail-matching engine, the gate-advisory core, and the predicted-gate orchestrator", () => {
+    expect(ENGINE_DECISION_GUARDRAIL_GLOBS).toContain("packages/loopover-engine/src/signals/change-guardrail.ts");
+    expect(ENGINE_DECISION_GUARDRAIL_GLOBS).toContain("packages/loopover-engine/src/advisory/gate-advisory.ts");
+    expect(ENGINE_DECISION_GUARDRAIL_GLOBS).toContain("packages/loopover-engine/src/predicted-gate.ts");
+  });
+
+  it("a PR touching only the guardrail-matching engine trips the hard guardrail", () => {
+    expect(isGuardrailHit(["packages/loopover-engine/src/signals/change-guardrail.ts"], resolveHardGuardrailGlobs(null))).toBe(
+      true,
+    );
+  });
+
+  it("a PR touching only the gate-advisory core trips the hard guardrail", () => {
+    expect(isGuardrailHit(["packages/loopover-engine/src/advisory/gate-advisory.ts"], resolveHardGuardrailGlobs(null))).toBe(true);
+  });
+
+  it("a PR touching only the predicted-gate orchestrator trips the hard guardrail", () => {
+    expect(isGuardrailHit(["packages/loopover-engine/src/predicted-gate.ts"], resolveHardGuardrailGlobs(null))).toBe(true);
+  });
+});
+
 describe("resolveHardGuardrailGlobs", () => {
   it("uses invariant guardrails when effective settings omit hardGuardrailGlobs", () => {
     expect(resolveHardGuardrailGlobs(undefined)).toEqual(DEFAULT_HARD_GUARDRAIL_GLOBS);