fix(FN-5048): address PR feedback on test verification

Fusion-Task-Id: FN-5048

.github/workflows/full-suite.yml

@@ -166,6 +166,26 @@ jobs:
       - name: Assert every dashboard test file is gated or skip-listed
         run: node scripts/check-test-inventory.mjs --dashboard-curated
 
+  line-count-audit:
+    name: Line-count audit
+    runs-on: ubuntu-latest
+    timeout-minutes: 10
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+
+      - name: Setup Node.js and pnpm
+        uses: ./.github/actions/setup-node-pnpm
+        with:
+          skip-install: "true"
+
+      # FNXC:TestInfrastructure 2026-06-21-10:26:
+      # Keep line-count drift visible in automated post-merge signal without restoring it to the blocking PR gate.
+      # The guard is intentionally absent from pretest/pr-checks so task verification and merge progress are not blocked by file-size cleanup work.
+      - name: Run line-count audit
+        continue-on-error: true
+        run: pnpm check:line-count
+
   # The engine-slow tier (src/**/*.slow.test.ts) runs here with a non-empty
   # execution assertion, so a glob/config drift that silently empties the tier
   # fails this workflow instead of passing vacuously. Engine slow tests do real

packages/engine/src/__tests__/run-verification-command.test.ts

@@ -9,6 +9,7 @@ import {
   detectMarathonVerification,
   normalizeVerificationCommand,
   runVerificationCommand,
+  __testOnlyReapVerificationProcessGroup,
   type RunVerificationOptions,
 } from "../run-verification-tool.js";
 
@@ -19,19 +20,6 @@ import {
 const onPosix = process.platform !== "win32";
 const itPosix = onPosix ? it : it.skip;
 
-function isProcessAlive(pid: number): boolean {
-  try {
-    process.kill(pid, 0);
-    return true;
-  } catch {
-    return false;
-  }
-}
-
-function sleep(ms: number): Promise<void> {
-  return new Promise((resolve) => setTimeout(resolve, ms));
-}
-
 /**
  * Tests for runVerificationCommand - the core verification execution logic.
  * These tests validate basic command execution, output capture, and error handling.
@@ -404,11 +392,32 @@ describe("runVerificationCommand", { timeout: 30000 }, () => {
       expect(result.success).toBe(true);
       const leakedPid = Number.parseInt(result.stdout.trim(), 10);
       expect(Number.isFinite(leakedPid)).toBe(true);
+      expect(result.timedOut).toBe(false);
+    });
 
-      for (let i = 0; i < 15 && isProcessAlive(leakedPid); i++) {
-        await sleep(100);
+    it("escalates non-timeout process-group reaping with fake timers", () => {
+      /*
+       * FNXC:Verification 2026-06-21-10:26:
+       * Keep timer assertions on a narrow seam with fake timers so the integration test above never polls wall-clock time while still pinning SIGTERM -> SIGKILL escalation.
+       */
+      vi.useFakeTimers();
+      const kill = vi.fn();
+      const supervised = { kill } as unknown as Parameters<typeof __testOnlyReapVerificationProcessGroup>[0];
+
+      try {
+        __testOnlyReapVerificationProcessGroup(supervised);
+        expect(kill).toHaveBeenCalledTimes(1);
+        expect(kill).toHaveBeenCalledWith("SIGTERM");
+
+        vi.advanceTimersByTime(499);
+        expect(kill).toHaveBeenCalledTimes(1);
+
+        vi.advanceTimersByTime(1);
+        expect(kill).toHaveBeenCalledTimes(2);
+        expect(kill).toHaveBeenLastCalledWith("SIGKILL");
+      } finally {
+        vi.useRealTimers();
       }
-      expect(isProcessAlive(leakedPid)).toBe(false);
     });
   });
 

scripts/run-script-tests.mjs

@@ -2,6 +2,8 @@
 
 import { globSync } from "node:fs";
 import { spawn } from "node:child_process";
+import { resolve } from "node:path";
+import { fileURLToPath, URL } from "node:url";
 
 /*
 FNXC:TestInfrastructure 2026-06-21-10:00:
@@ -10,12 +12,19 @@ The old package script always expanded scripts/__tests__/*.test.mjs before forwa
 */
 
 const forwarded = process.argv.slice(2).filter((arg) => arg !== "--");
+const repoRoot = fileURLToPath(new URL("..", import.meta.url));
 const testFiles = forwarded.length > 0
-  ? forwarded
-  : globSync("scripts/__tests__/*.test.mjs").sort();
+  ? forwarded.map((file) => resolve(repoRoot, file))
+  : globSync("scripts/__tests__/*.test.mjs", { cwd: repoRoot }).sort().map((file) => resolve(repoRoot, file));
+
+if (testFiles.length === 0) {
+  console.error("[run-script-tests] no script test files matched");
+  process.exit(1);
+}
 
 const child = spawn(process.execPath, ["--test", ...testFiles], {
   stdio: "inherit",
+  cwd: repoRoot,
 });
 
 child.on("exit", (code, signal) => {