test(helpers): extract the temp-repo lifecycle, collapsing five hand-rolled cleanups into one

Four cfg integration tests each hand-rolled a `tmpDirs` array, a
mkdtemp-and-register step, and an `afterAll` rmSync. It is actually five
registrations across six creation sites — `pipeline-pdg.test.ts` keeps a
second pool for its C-family fixtures.

Seeding genuinely varies four ways (recursive cpSync, single copyFileSync,
inline mkdir+writeFile, and nothing at all), so a fixture-copier helper
would have fitted about half the sites and made things worse. Extracted the
LIFECYCLE instead — mkdtemp, register, afterAll cleanup — which is
byte-identical at all five registrations and is the correctness-critical
part. `dir()` returns an empty registered directory for callers that seed
themselves; `fromFixture()` covers the common case. That fits 6/6.

The duplication had already produced a latent defect: `cFamilyTmpDirs` was
cleaned by TWO `afterAll` blocks, harmless only because `rmSync` was called
with `force: true`. Now one hook.

`createTempDirPool` is a function called from each test file's module scope
rather than a top-level hook in the helper, because under ESM caching a
module-level `afterAll` would register once, against whichever file
imported it first. That hazard is documented in the helper.

Raw line count is roughly neutral (-44 across the tests, +62 for the
helper, 29 of which are the rationale). The win is that a cleanup invariant
went from five copies to one.

Cleanup verified empirically, including the failure path: a throwaway suite
whose `beforeAll` throws still has its directory removed, and every
temp directory created by the four migrated files is gone after a run.
46 tests pass across the four files.

Refs #2802

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

gitnexus/test/helpers/temp-dir-pool.ts

@@ -0,0 +1,62 @@
+/**
+ * Temp-directory lifecycle for pipeline-level integration tests.
+ *
+ * The pipeline mutates the repo it is handed (parse caches, `.gitnexus/`), so
+ * these tests each run against a throwaway copy of a fixture. Every consumer
+ * had hand-rolled the SAME three parts — a `string[]` of created dirs, a
+ * `mkdtempSync` that pushes onto it, and an `afterAll` that `rmSync`s the lot.
+ * Extracted at the fourth consumer (`pipeline-pdg`, `pipeline-pdg-streaming`,
+ * `interproc-taint`, `pdg-chained-receiver-callees`); the copies had already
+ * drifted — `pipeline-pdg` registered two cleanup hooks over one array.
+ *
+ * Only the LIFECYCLE is shared, deliberately: seeding differs per test (a
+ * recursive fixture copy, a single file, an inline-written source, or nothing
+ * at all), so `dir()` hands back an empty registered directory and the caller
+ * fills it however it likes. `fromFixture()` is the common case.
+ *
+ * `createTempDirPool` calls `afterAll` itself, so it must be called from a
+ * test file's module scope (not from this module's top level — ESM caching
+ * would register the hook once, for whichever file imported it first).
+ * Directories are registered at creation, before any seeding runs, so a
+ * fixture copy or a pipeline run that throws still leaves them cleaned up.
+ */
+
+import fs from 'fs';
+import os from 'os';
+import path from 'path';
+import { afterAll } from 'vitest';
+
+export interface TempDirPool {
+  /** A fresh empty temp dir, registered for cleanup. Seed it yourself. */
+  dir(): string;
+  /** A fresh temp dir seeded with a recursive copy of `fixture`. */
+  fromFixture(fixture: string): string;
+}
+
+/**
+ * Create a pool of temp directories that are removed after the calling test
+ * file finishes. `prefix` is the `mkdtemp` prefix (e.g. `'gn-pdg-'`), kept
+ * per-pool so a leaked directory still names the suite that made it.
+ */
+export function createTempDirPool(prefix: string): TempDirPool {
+  const created: string[] = [];
+
+  const dir = (): string => {
+    const made = fs.mkdtempSync(path.join(os.tmpdir(), prefix));
+    created.push(made);
+    return made;
+  };
+
+  afterAll(() => {
+    for (const d of created) fs.rmSync(d, { recursive: true, force: true });
+  });
+
+  return {
+    dir,
+    fromFixture(fixture: string): string {
+      const made = dir();
+      fs.cpSync(fixture, made, { recursive: true });
+      return made;
+    },
+  };
+}

gitnexus/test/integration/cfg/interproc-taint.test.ts

@@ -12,33 +12,23 @@
  * the parse worker, and a stale dist is a spurious red.
  */
 
-import { describe, it, expect, afterAll } from 'vitest';
+import { describe, it, expect } from 'vitest';
-import fs from 'fs';
-import os from 'os';
 import path from 'path';
 import { runPipelineFromRepo } from '../../../src/core/ingestion/pipeline.js';
 import type { PipelineResult } from '../../../src/types/pipeline.js';
 import { decodeTaintPath } from '../../../src/core/ingestion/taint/path-codec.js';
+import { createTempDirPool } from '../../helpers/temp-dir-pool.js';
 
 const FIXTURE = path.join(__dirname, 'fixtures', 'interproc-repo');
 
-const tmpDirs: string[] = [];
+const repos = createTempDirPool('gn-interproc-');
-function freshRepo(): string {
+const freshRepo = (): string => repos.fromFixture(FIXTURE);
-  const dir = fs.mkdtempSync(path.join(os.tmpdir(), 'gn-interproc-'));
-  fs.cpSync(FIXTURE, dir, { recursive: true });
-  tmpDirs.push(dir);
-  return dir;
-}
 
 function taintPaths(result: PipelineResult) {
   return [...result.graph.iterRelationships()].filter((r) => r.type === 'TAINT_PATH');
 }
 
 describe('U9 — end-to-end interprocedural taint (--pdg)', () => {
-  afterAll(() => {
-    for (const d of tmpDirs) fs.rmSync(d, { recursive: true, force: true });
-  });
-
   it('with --pdg: composes a cross-file source→sink into a TAINT_PATH edge', async () => {
     const result = await runPipelineFromRepo(freshRepo(), () => {}, { pdg: true });
     const paths = taintPaths(result);

gitnexus/test/integration/cfg/pdg-chained-receiver-callees.test.ts

@@ -47,11 +47,11 @@
  * fixture is shared by eight suites including a snapshot test, so growing it to
  * cover one seam churns unrelated expectations.
  */
-import { describe, it, expect, beforeAll, afterAll } from 'vitest';
+import { describe, it, expect, beforeAll } from 'vitest';
 import fs from 'fs';
-import os from 'os';
 import path from 'path';
 import { runPipelineFromRepo } from '../../../src/core/ingestion/pipeline.js';
+import { createTempDirPool } from '../../helpers/temp-dir-pool.js';
 // The PRODUCTION reader of the cell: splits on `CALLEE_ID_SEP`
 // (src/core/ingestion/cfg/emit.ts) and drops the truncation sentinel. Both the
 // statement-precise bridge and the inter-procedural descent go through it, so
@@ -225,7 +225,7 @@ interface BlockCell {
   readonly ids: readonly string[];
 }
 
-const tmpDirs: string[] = [];
+const repos = createTempDirPool('gn-pdg-chain-');
 let blocks: readonly BlockCell[] = [];
 
 function blocksFor(marker: string): readonly BlockCell[] {
@@ -251,10 +251,9 @@ function assertChainReachesPdg(shape: ReceiverShape): void {
 
 describe('PDG calleeIds — chained receiver calls by receiver form (#2802 follow-up)', () => {
   beforeAll(async () => {
-    const dir = fs.mkdtempSync(path.join(os.tmpdir(), 'gn-pdg-chain-'));
+    const dir = repos.dir();
     fs.mkdirSync(path.join(dir, path.dirname(FIXTURE_PATH)));
     fs.writeFileSync(path.join(dir, FIXTURE_PATH), CHAINED_SOURCE);
-    tmpDirs.push(dir);
 
     const result = await runPipelineFromRepo(dir, () => {}, { pdg: true });
     const collected: BlockCell[] = [];
@@ -268,10 +267,6 @@ describe('PDG calleeIds — chained receiver calls by receiver form (#2802 follo
     blocks = collected;
   }, 180000);
 
-  afterAll(() => {
-    for (const d of tmpDirs) fs.rmSync(d, { recursive: true, force: true });
-  });
-
   it('every receiver shape contributes exactly one chained-call block', () => {
     const counts = Object.fromEntries(
       RECEIVER_SHAPES.map((s) => [s.name, blocksFor(s.marker).length]),

gitnexus/test/integration/cfg/pipeline-pdg-streaming.test.ts

@@ -15,13 +15,13 @@
  * for its CSV dir), differing ONLY in `streamPdgEmit`, so streaming is the only
  * variable.
  */
-import { describe, it, expect, afterAll } from 'vitest';
+import { describe, it, expect } from 'vitest';
 import fs from 'fs';
-import os from 'os';
 import path from 'path';
 import { runPipelineFromRepo } from '../../../src/core/ingestion/pipeline.js';
 import { loadParseCache } from '../../../src/storage/parse-cache.js';
 import type { PipelineResult } from '../../../src/types/pipeline.js';
+import { createTempDirPool } from '../../helpers/temp-dir-pool.js';
 
 const FIXTURE = path.join(__dirname, 'fixtures', 'pdg-repo');
 // A `.vue` SFC importing a `.ts` module: the TS module is PDG-emitted in BOTH
@@ -36,18 +36,10 @@ const PDG_EDGE_TYPES = new Set([
   'SANITIZES',
 ]);
 
-const tmpDirs: string[] = [];
+const repos = createTempDirPool('gn-pdg-stream-');
-function freshRepo(fixture: string = FIXTURE): string {
+const storages = createTempDirPool('gn-pdg-store-');
-  const dir = fs.mkdtempSync(path.join(os.tmpdir(), 'gn-pdg-stream-'));
+const freshRepo = (fixture: string = FIXTURE): string => repos.fromFixture(fixture);
-  fs.cpSync(fixture, dir, { recursive: true });
+const freshStorage = (): string => storages.dir();
-  tmpDirs.push(dir);
-  return dir;
-}
-function freshStorage(): string {
-  const dir = fs.mkdtempSync(path.join(os.tmpdir(), 'gn-pdg-store-'));
-  tmpDirs.push(dir);
-  return dir;
-}
 
 function pdgCounts(result: PipelineResult): { basicBlocks: number; pdgEdges: number } {
   let basicBlocks = 0;
@@ -62,10 +54,6 @@ function pdgCounts(result: PipelineResult): { basicBlocks: number; pdgEdges: num
 }
 
 describe('#2202 — streaming PDG emit end-to-end', () => {
-  afterAll(() => {
-    for (const d of tmpDirs) fs.rmSync(d, { recursive: true, force: true });
-  });
-
   it('streams the PDG layer out of the graph while preserving the emitted set', async () => {
     // ── Baseline: --pdg on, streaming OFF (durable cache, same as streamed) ──
     const baseStorage = freshStorage();

gitnexus/test/integration/cfg/pipeline-pdg.test.ts

@@ -1,12 +1,12 @@
-import { describe, it, expect, afterAll } from 'vitest';
+import { describe, it, expect } from 'vitest';
 import fs from 'fs';
-import os from 'os';
 import path from 'path';
 import crypto from 'crypto';
 import { runPipelineFromRepo } from '../../../src/core/ingestion/pipeline.js';
 import type { PipelineResult } from '../../../src/types/pipeline.js';
 import { decodeTaintPath } from '../../../src/core/ingestion/taint/path-codec.js';
 import { fixtureTaintTotals } from '../../helpers/taint-fixture.js';
+import { createTempDirPool } from '../../helpers/temp-dir-pool.js';
 import { isLanguageAvailable } from '../../../src/core/tree-sitter/parser-loader.js';
 import { SupportedLanguages } from '../../../src/config/supported-languages.js';
 
@@ -45,19 +45,10 @@ function counts(result: PipelineResult): {
   return { basicBlocks, cfgEdges, reachingDefs, tainted, sanitizes, cdg };
 }
 
-const tmpDirs: string[] = [];
+const repos = createTempDirPool('gn-pdg-');
-function freshRepo(): string {
+const freshRepo = (): string => repos.fromFixture(FIXTURE);
-  const dir = fs.mkdtempSync(path.join(os.tmpdir(), 'gn-pdg-'));
-  fs.cpSync(FIXTURE, dir, { recursive: true });
-  tmpDirs.push(dir);
-  return dir;
-}
 
 describe('U7 — end-to-end --pdg pipeline', () => {
-  afterAll(() => {
-    for (const d of tmpDirs) fs.rmSync(d, { recursive: true, force: true });
-  });
-
   it('with --pdg on: emits BasicBlock nodes + CFG edges into the graph', async () => {
     const result = await runPipelineFromRepo(freshRepo(), () => {}, { pdg: true });
     const { basicBlocks, cfgEdges, reachingDefs } = counts(result);
@@ -288,11 +279,11 @@ const REMAINING_LANGS: ReadonlyArray<{
   { lang: 'Vue', fixture: 'vue-hazards.vue', hazard: 'shouldStop' }, // eventLoop: while(true)
 ];
 
-const cFamilyTmpDirs: string[] = [];
+// Single-file seeding, so this pool uses `dir()` rather than `fromFixture()`.
+const langRepos = createTempDirPool('gn-pdg-lang-');
 function freshLangRepo(fixture: string): string {
-  const dir = fs.mkdtempSync(path.join(os.tmpdir(), 'gn-pdg-lang-'));
+  const dir = langRepos.dir();
   fs.copyFileSync(path.join(C_FAMILY_FIXTURES, fixture), path.join(dir, fixture));
-  cFamilyTmpDirs.push(dir);
   return dir;
 }
 
@@ -396,10 +387,6 @@ function cdgSourcedInHazardFunction(result: PipelineResult, hazardMarker: string
 }
 
 describe('U7 — C-family worker-mode --pdg pipeline', () => {
-  afterAll(() => {
-    for (const d of cFamilyTmpDirs) fs.rmSync(d, { recursive: true, force: true });
-  });
-
   for (const { lang, fixture, hazard } of C_FAMILY) {
     it(`${lang}: --pdg on emits BasicBlock + CFG + REACHING_DEF + CDG (> 0) via the worker`, async () => {
       const result = await runPipelineFromRepo(freshLangRepo(fixture), () => {}, WORKER_PDG);
@@ -478,10 +465,6 @@ describe('U7 — C-family worker-mode --pdg pipeline', () => {
 });
 
 describe('U7 — remaining languages worker-mode --pdg pipeline (#2195 capstone)', () => {
-  afterAll(() => {
-    for (const d of cFamilyTmpDirs) fs.rmSync(d, { recursive: true, force: true });
-  });
-
   for (const { lang, fixture, hazard, vendored } of REMAINING_LANGS) {
     // Vendored grammars (Swift/Kotlin/Dart) may lack a prebuild on the CI
     // platform — skip rather than fail when the grammar can't load (#2197 U4).