From 64c66c1e5c4aac23f49e52035c1414a7c63817c4 Mon Sep 17 00:00:00 2001
From: Fusion <noreply@runfusion.ai>
Date: Sun, 10 May 2026 10:29:49 -0700
Subject: [PATCH] feat(FN-3933): coordinate temp dir cleanup to harden testing
 suite isolatio

Documents and tests a temp directory isolation fix in the core test suite, coordinating cleanup to prevent cross-test contamination.

Fusion-Task-Id: FN-3933
---
 docs/bugs/testing-suite-hardening.md   |  1 +
 packages/core/src/__tests__/db.test.ts | 31 +++++++++++++++++++++-----
 2 files changed, 26 insertions(+), 6 deletions(-)

diff --git a/docs/bugs/testing-suite-hardening.md b/docs/bugs/testing-suite-hardening.md
index f36f80760..fde60dd7e 100644
--- a/docs/bugs/testing-suite-hardening.md
+++ b/docs/bugs/testing-suite-hardening.md
@@ -29,3 +29,4 @@ why it broke, how it was fixed, and what command verified the fix.
 | TSH-011 | PR build coverage | While reducing PR shard minutes, the workflow temporarily had no standalone `pnpm build` job. | The old workflow only had lint, typecheck, and test shards, so removing the shard-local build also removed PR build coverage. | Added an explicit `build` job to `pr-checks.yml` and updated the workflow contract test to require it. | `pnpm --filter @runfusion/fusion exec vitest run src/__tests__/ci-workflow.test.ts --silent=passed-only --reporter=dot` and `pnpm build` |
 | TSH-012 | Warning filtering | The first SQLite warning filter also installed a `process.on("warning")` listener that could duplicate unrelated warnings. | Node still prints non-filtered warnings by default, so manually writing them again made future warning output noisier. | The shared setup now only wraps `process.emitWarning` for the known SQLite experimental warning, and the dashboard noisy-output marker list no longer suppresses generic trace-warning guidance. | `pnpm --filter @fusion/core typecheck`, `pnpm --filter @fusion/core exec vitest run src/__tests__/central-db.test.ts --silent=passed-only --reporter=dot`, and `pnpm test:full` |
 | TSH-013 | Dashboard default runtime | The default dashboard package test still took about 9 minutes after the noise cleanup. | `pnpm --filter @fusion/dashboard test` continued to run every app/jsdom and API/node file, including exhaustive modal/view permutations and broad route matrices intended for deeper sweeps. | Added curated `dashboard-app-quality` and `dashboard-api-quality` Vitest projects for the default package gate, kept exhaustive coverage behind `test:deep`, `test:app`, and `test:api`, and documented when to run each lane. | `/usr/bin/time -p pnpm --filter @fusion/dashboard test` (148 files, 3642 tests, `real 91.73`), `/usr/bin/time -p pnpm --filter @fusion/dashboard test:deep` (419 files, 10747 tests, `real 335.47`), and `/usr/bin/time -p pnpm test:full` (`real 308.34`) |
+| TSH-014 | Core temp-dir cleanup | `kb-db-test-*` directories could leak after `db.test.ts` runs and trip isolation checks. | `afterEach(async)` and module-level `afterAll(async)` both cleared `createdTmpDirs` before async `rm(...)` completed, so hook timing races could hide leftovers from final teardown during worker shutdown. | Coordinated cleanup bookkeeping by deleting set entries only after per-dir removal, kept `afterEach` as async best-effort cleanup, and switched the final `afterAll` fallback to defensive synchronous `rmSync(..., { recursive: true, force: true })`. | `pnpm --filter @fusion/core test -- src/__tests__/db.test.ts` and `node scripts/check-test-isolation.mjs --before && pnpm --filter @fusion/core test && node scripts/check-test-isolation.mjs` |
diff --git a/packages/core/src/__tests__/db.test.ts b/packages/core/src/__tests__/db.test.ts
index e8c4ea393..78c2e5b65 100644
--- a/packages/core/src/__tests__/db.test.ts
+++ b/packages/core/src/__tests__/db.test.ts
@@ -26,10 +26,31 @@ function makeTmpDir(): string {
   return dir;
 }
 
-afterAll(async () => {
+async function cleanupTmpDirsAsync(): Promise<void> {
   const cleanup = Array.from(createdTmpDirs);
-  createdTmpDirs.clear();
-  await Promise.all(cleanup.map((dir) => rm(dir, { recursive: true, force: true })));
+  await Promise.all(
+    cleanup.map(async (dir) => {
+      await rm(dir, { recursive: true, force: true });
+      createdTmpDirs.delete(dir);
+    }),
+  );
+}
+
+function cleanupTmpDirsSync(): void {
+  const cleanup = Array.from(createdTmpDirs);
+  for (const dir of cleanup) {
+    try {
+      rmSync(dir, { recursive: true, force: true });
+    } catch {
+      // best-effort fallback during teardown
+    } finally {
+      createdTmpDirs.delete(dir);
+    }
+  }
+}
+
+afterAll(() => {
+  cleanupTmpDirsSync();
 });
 
 describe("Database", () => {
@@ -50,9 +71,7 @@ describe("Database", () => {
     } catch {
       // already closed
     }
-    const cleanup = Array.from(createdTmpDirs);
-    createdTmpDirs.clear();
-    await Promise.all(cleanup.map((dir) => rm(dir, { recursive: true, force: true })));
+    await cleanupTmpDirsAsync();
   });
 
   describe("initialization", () => {