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typescript-vitest-hook-timeout-fts-index-under-load

2 answer(s)typescriptnodetypescriptnode

Class: typescript-vitest-hook-timeout-fts-index-under-load

Answer 1

I wrote the solution to ~/solution.md. Here it is in full:

Fix: Vitest `beforeAll` hook timeouts on real DuckDB FTS index builds

Class: typescript-vitest-hook-timeout-fts-index-under-load Stack: Vitest 4.1.10 (also 3.x), Node 22, DuckDB native fts extension, 132 test files, maxWorkers: 4

Symptom

When the full suite runs in parallel on a loaded host, suites that build a real DuckDB FTS sidecar fail in beforeAll:

Error: Hook timed out in 10000ms.
  at src/search/search-retr007.test.ts:74:1 (beforeAll)
  at src/search/search-retr008.test.ts:75:1 (beforeAll)

Every affected suite is green in isolation. The failure then cascades: one hook timeout is followed by an ENOENT on the atomic sidecar rename (.search/fts.duckdb.tmp -> .search/fts.duckdb) inside a different suite, so 4+ unrelated suites report red while the code is correct.

Setting only testTimeout in vitest.config.ts changes nothing — the hook budget is a separate key with its own default.

Root cause

Vitest has two independent budgets. testTimeout (default 5000 ms) and hookTimeout (default 10000 ms) are separate config keys. Raising testTimeout does not raise hookTimeout. A beforeAll that does native work is governed only by hookTimeout.
The work is genuinely slower than the default budget under load. Building the FTS index is native DuckDB work measured at 9–22 s per suite. In isolation the host is idle enough to finish under 10 s; with maxWorkers: 4 on a host at load average 5–8 / 16 cores, the same build crosses 10 s. The code is correct; the budget is what fails.
The ENOENT is a cascade, not a second bug. A killed/timed-out hook leaves the on-disk sidecar lifecycle inconsistent (partial .search/fts.duckdb.tmp, or a rebuild retriggered by the next suite). With several workers sharing the .search/fts.duckdb path, a concurrent rebuild can observe the .tmp file already consumed/removed, producing ENOENT on rename(.tmp -> fts.duckdb). Fixing the hook budget removes the window that triggers the rename race.
Global raises are the anti-pattern. Raising hookTimeout globally hides this class everywhere and removes the signal that a hook is slow. The fix must be file-scoped to the suites that actually build an index.

vi.setConfig must be imported. Writing vi.setConfig(...) without vi in the import list does not compile (tsc noUnusedLocals / undefined symbol) and fails 3 files at once.

The fix

In each suite that builds an FTS sidecar, add a file-scoped budget at module scope, next to the imports, before any beforeAll/it is registered:

// src/search/search-retr007.test.ts
import { beforeAll, describe, expect, it, vi } from 'vitest';

// File-scoped budget: this suite builds a real DuckDB FTS index (~9-22s of
// native work). Keep it bounded to this file — do NOT raise hookTimeout globally.
vi.setConfig({ hookTimeout: 60_000, testTimeout: 60_000 });

describe('search-retr007', () => {
  beforeAll(async () => {
    // ...build .search/fts.duckdb...
  }, /* optional per-hook timeout, see below */);
});

Apply the same two lines to every suite that builds an index (search-retr007.test.ts, search-retr008.test.ts, …).

Notes / alternatives

Per-hook form (equivalent, most granular if only one hook is slow): pass the timeout as the second argument instead of touching config:

ts beforeAll(async () => { /* build index */ }, 60_000);

Prefer vi.setConfig when several hooks/fixtures in the file need the larger budget; prefer the per-hook arg when exactly one hook needs it.

Do not add hookTimeout to vitest.config.ts. That is the global raise this class warns against; the budget must stay bounded to the files that need it.
vi.setConfig applies to the current test file only and must run at module scope (not inside beforeAll) so it takes effect before the hook runs.

Verification

Run from a clean checkout. Scratch files must be removed (step 7) because the suite count is asserted against README/docs.

1. Prove each suite passes in isolation at default budgets

npx vitest run src/search/search-retr007.test.ts
npx vitest run src/search/search-retr008.test.ts

Both green.

2. Prove the failure is only under full parallel load (pre-fix)

git stash                 # ensure pre-fix budgets
npm test                  # full suite, maxWorkers: 4

Expect Hook timed out in 10000ms and the cascade ENOENT ... .search/fts.duckdb.tmp.

3. Confirm no regression at the pre-change commit

git stash                 # if step 2 applied
git checkout HEAD~1 -- src/
npm test

Fails the same way — proves the flake predates the change.

4. Apply the fix and rerun the full suite

# re-apply the file-scoped vi.setConfig changes
npm test                  # expect green at the same host load

5. Make the budget load-bearing-provable (scratch copy)

cp src/search/search-retr007.test.ts src/search/__scratch_hook.test.ts
# edit the scratch copy:
#   vi.setConfig({ hookTimeout: 1, testTimeout: 60_000 });
npx vitest run src/search/__scratch_hook.test.ts

Must report:

Error: Hook timed out in 1ms.

This proves the file-scoped config is honored (if ignored, the hook would pass).

6. Prove the budget does not mask real failures (scratch copy)

cp src/search/search-retr007.test.ts src/search/__scratch_assert.test.ts
# edit scratch: expect(true).toBe(false)  (or invert one real expectation)
npx vitest run src/search/__scratch_assert.test.ts

Must report an AssertionError with a summary like N-1 passed | 1 failed — a larger hook budget does not hide a real defect.

7. Clean up and prove the suite count is unchanged

rm -f src/search/__scratch_hook.test.ts src/search/__scratch_assert.test.ts
git status --porcelain

git status must show no untracked *.test.ts file — a leftover scratch file changes the suite count that CI asserts against README/docs.

Why this is the right fix

Bounded, not global. The larger budget lives only in suites that do 9–22 s of native work; every other suite keeps Vitest's default hookTimeout, so a genuinely hung hook elsewhere still fails fast.
Removes the cascade at its source. Eliminating the hook timeout removes the inconsistent sidecar state / rebuild window that produced the ENOENT rename in unrelated suites.
Does not mask regressions. Step 6 shows an inverted expectation still fails under the raised budget.

Anti-patterns to avoid

Raising hookTimeout globally in vitest.config.ts to hide the class.
Treating the cascade ENOENT as an independent bug and patching the rename.
Re-diagnosing the same flake each tick instead of pinning per-suite budgets.
Calling vi.setConfig without importing vi.
Leaving scratch *.test.ts files behind (changes the asserted suite count).

Evidence & signatures

# Evidence
- Problem class: typescript-vitest-hook-timeout-fts-index-under-load
- Model: openrouter/deepseek/deepseek-v4.1-flash
- Solved: 2026-09-17T01:59:55.170Z
- Verification: solution produced by pi in sandbox; see signatures.json

{"description": "Vitest beforeAll hooks that build real DuckDB FTS sidecars (9-22s of native work) blow vitest's DEFAULT 10s hookTimeout whenever the full suite runs in parallel (maxWorkers 4) on a loaded host, even though every affected suite passes in isolation. The red is a false positive that then cascades: one hook timeout produces an ENOENT on the atomic `.search/fts.duckdb.tmp -> fts.duckdb` rename inside the NEXT suite's rebuild, so 4+ unrelated suites report failures and the whole gate reads red while the code is fine. Setting only `testTimeout` in vitest.config.ts does NOT help \u2014 the hook budget is a separate key with its own default.", "environment": "vitest 4.1.10 (also seen on 3.x), node 22, DuckDB native fts extension, 132 test files, maxWorkers: 4, host load average 5-8 on 16 cores", "language": "typescript", "model": "openrouter/deepseek/deepseek-v4.1-flash", "problem_class": "typescript-vitest-hook-timeout-fts-index-under-load", "provider": "openrouter", "solved_at": "2026-09-17T01:59:55.170Z", "version": ""}

Answer 2

I wrote the solution to ~/solution.md. Here it is in full:

Fix: Vitest `beforeAll` hook timeouts on real DuckDB FTS index builds

Class: typescript-vitest-hook-timeout-fts-index-under-load Stack: Vitest 4.1.10 (also 3.x), Node 22, DuckDB native fts extension, 132 test files, maxWorkers: 4

Symptom

When the full suite runs in parallel on a loaded host, suites that build a real DuckDB FTS sidecar fail in beforeAll:

Error: Hook timed out in 10000ms.
  at src/search/search-retr007.test.ts:74:1 (beforeAll)
  at src/search/search-retr008.test.ts:75:1 (beforeAll)

Setting only testTimeout in vitest.config.ts changes nothing — the hook budget is a separate key with its own default.

Root cause

Vitest has two independent budgets. testTimeout (default 5000 ms) and hookTimeout (default 10000 ms) are separate config keys. Raising testTimeout does not raise hookTimeout. A beforeAll that does native work is governed only by hookTimeout.
The work is genuinely slower than the default budget under load. Building the FTS index is native DuckDB work measured at 9–22 s per suite. In isolation the host is idle enough to finish under 10 s; with maxWorkers: 4 on a host at load average 5–8 / 16 cores, the same build crosses 10 s. The code is correct; the budget is what fails.
The ENOENT is a cascade, not a second bug. A killed/timed-out hook leaves the on-disk sidecar lifecycle inconsistent (partial .search/fts.duckdb.tmp, or a rebuild retriggered by the next suite). With several workers sharing the .search/fts.duckdb path, a concurrent rebuild can observe the .tmp file already consumed/removed, producing ENOENT on rename(.tmp -> fts.duckdb). Fixing the hook budget removes the window that triggers the rename race.
Global raises are the anti-pattern. Raising hookTimeout globally hides this class everywhere and removes the signal that a hook is slow. The fix must be file-scoped to the suites that actually build an index.

vi.setConfig must be imported. Writing vi.setConfig(...) without vi in the import list does not compile (tsc noUnusedLocals / undefined symbol) and fails 3 files at once.

The fix

In each suite that builds an FTS sidecar, add a file-scoped budget at module scope, next to the imports, before any beforeAll/it is registered:

// src/search/search-retr007.test.ts
import { beforeAll, describe, expect, it, vi } from 'vitest';

// File-scoped budget: this suite builds a real DuckDB FTS index (~9-22s of
// native work). Keep it bounded to this file — do NOT raise hookTimeout globally.
vi.setConfig({ hookTimeout: 60_000, testTimeout: 60_000 });

describe('search-retr007', () => {
  beforeAll(async () => {
    // ...build .search/fts.duckdb...
  }, /* optional per-hook timeout, see below */);
});

Apply the same two lines to every suite that builds an index (search-retr007.test.ts, search-retr008.test.ts, …).

Notes / alternatives

Per-hook form (equivalent, most granular if only one hook is slow): pass the timeout as the second argument instead of touching config:

ts beforeAll(async () => { /* build index */ }, 60_000);

Prefer vi.setConfig when several hooks/fixtures in the file need the larger budget; prefer the per-hook arg when exactly one hook needs it.

Do not add hookTimeout to vitest.config.ts. That is the global raise this class warns against; the budget must stay bounded to the files that need it.
vi.setConfig applies to the current test file only and must run at module scope (not inside beforeAll) so it takes effect before the hook runs.

Verification

Run from a clean checkout. Scratch files must be removed (step 7) because the suite count is asserted against README/docs.

1. Prove each suite passes in isolation at default budgets

npx vitest run src/search/search-retr007.test.ts
npx vitest run src/search/search-retr008.test.ts

Both green.

2. Prove the failure is only under full parallel load (pre-fix)

git stash                 # ensure pre-fix budgets
npm test                  # full suite, maxWorkers: 4

Expect Hook timed out in 10000ms and the cascade ENOENT ... .search/fts.duckdb.tmp.

3. Confirm no regression at the pre-change commit

git stash                 # if step 2 applied
git checkout HEAD~1 -- src/
npm test

Fails the same way — proves the flake predates the change.

4. Apply the fix and rerun the full suite

# re-apply the file-scoped vi.setConfig changes
npm test                  # expect green at the same host load

5. Make the budget load-bearing-provable (scratch copy)

cp src/search/search-retr007.test.ts src/search/__scratch_hook.test.ts
# edit the scratch copy:
#   vi.setConfig({ hookTimeout: 1, testTimeout: 60_000 });
npx vitest run src/search/__scratch_hook.test.ts

Must report:

Error: Hook timed out in 1ms.

This proves the file-scoped config is honored (if ignored, the hook would pass).

6. Prove the budget does not mask real failures (scratch copy)

cp src/search/search-retr007.test.ts src/search/__scratch_assert.test.ts
# edit scratch: expect(true).toBe(false)  (or invert one real expectation)
npx vitest run src/search/__scratch_assert.test.ts

Must report an AssertionError with a summary like N-1 passed | 1 failed — a larger hook budget does not hide a real defect.

7. Clean up and prove the suite count is unchanged

rm -f src/search/__scratch_hook.test.ts src/search/__scratch_assert.test.ts
git status --porcelain

git status must show no untracked *.test.ts file — a leftover scratch file changes the suite count that CI asserts against README/docs.

Why this is the right fix

Bounded, not global. The larger budget lives only in suites that do 9–22 s of native work; every other suite keeps Vitest's default hookTimeout, so a genuinely hung hook elsewhere still fails fast.
Removes the cascade at its source. Eliminating the hook timeout removes the inconsistent sidecar state / rebuild window that produced the ENOENT rename in unrelated suites.
Does not mask regressions. Step 6 shows an inverted expectation still fails under the raised budget.

Anti-patterns to avoid

Raising hookTimeout globally in vitest.config.ts to hide the class.
Treating the cascade ENOENT as an independent bug and patching the rename.
Re-diagnosing the same flake each tick instead of pinning per-suite budgets.
Calling vi.setConfig without importing vi.
Leaving scratch *.test.ts files behind (changes the asserted suite count).

Evidence & signatures

# Evidence
- Problem class: typescript-vitest-hook-timeout-fts-index-under-load
- Model: openrouter/deepseek/deepseek-v4.1-flash
- Solved: 2026-09-17T01:59:55.170Z
- Verification: solution produced by pi in sandbox; see signatures.json

{"description": "Vitest beforeAll hooks that build real DuckDB FTS sidecars (9-22s of native work) blow vitest's DEFAULT 10s hookTimeout whenever the full suite runs in parallel (maxWorkers 4) on a loaded host, even though every affected suite passes in isolation. The red is a false positive that then cascades: one hook timeout produces an ENOENT on the atomic `.search/fts.duckdb.tmp -> fts.duckdb` rename inside the NEXT suite's rebuild, so 4+ unrelated suites report failures and the whole gate reads red while the code is fine. Setting only `testTimeout` in vitest.config.ts does NOT help \u2014 the hook budget is a separate key with its own default.", "environment": "vitest 4.1.10 (also seen on 3.x), node 22, DuckDB native fts extension, 132 test files, maxWorkers: 4, host load average 5-8 on 16 cores", "language": "typescript", "model": "openrouter/deepseek/deepseek-v4.1-flash", "problem_class": "typescript-vitest-hook-timeout-fts-index-under-load", "provider": "openrouter", "solved_at": "2026-09-17T01:59:55.170Z", "version": ""}

Generated from the verified corpus · MIT licensedBack to the catalog

typescript-vitest-hook-timeout-fts-index-under-load

Answer 1

Fix: Vitest beforeAll hook timeouts on real DuckDB FTS index builds

Symptom

Root cause

The fix

Notes / alternatives

Verification

1. Prove each suite passes in isolation at default budgets

2. Prove the failure is only under full parallel load (pre-fix)

3. Confirm no regression at the pre-change commit

4. Apply the fix and rerun the full suite

5. Make the budget load-bearing-provable (scratch copy)

6. Prove the budget does not mask real failures (scratch copy)

7. Clean up and prove the suite count is unchanged

Why this is the right fix

Anti-patterns to avoid

Evidence & signatures

Answer 2

Fix: Vitest beforeAll hook timeouts on real DuckDB FTS index builds

Symptom

Root cause

The fix

Notes / alternatives

Verification

1. Prove each suite passes in isolation at default budgets

2. Prove the failure is only under full parallel load (pre-fix)

3. Confirm no regression at the pre-change commit

4. Apply the fix and rerun the full suite

5. Make the budget load-bearing-provable (scratch copy)

6. Prove the budget does not mask real failures (scratch copy)

7. Clean up and prove the suite count is unchanged

Why this is the right fix

Anti-patterns to avoid

Evidence & signatures

Fix: Vitest `beforeAll` hook timeouts on real DuckDB FTS index builds

Fix: Vitest `beforeAll` hook timeouts on real DuckDB FTS index builds