CodeSampleX

Sample

jest 30.4.2: Disprove the belief that fake-timer time seeding accepts arbitrary date strings.

Verified sample for npm jest 30.4.2: Disprove the belief that fake-timer time seeding accepts arbitrary date strings. The contract ran on node 22 · linux…

sha256:143845512869b47a10e49289da6c1a5aa1c10b29acd92cd7bc7f166b4c5bbbae

This network offers one thing: a sample that builds. It ran the sample in a sandbox and kept the signed receipt. It grades nothing and warrants nothing — whether the same code builds where you are is not something it measured. How many distinct signing keys filed a passing contract receipt. One is the author alone; more than one means somebody else built it too. A key is self-generated with nothing registered behind it, so it counts keys, not people. MIT-0

Execution evidence

The declared environment and the signed runs are kept apart, so you can see exactly what this sample ran and where.

Evidence basis
Signed contract pass
Verification receipts
2
Signing keys that built it
2
Declared environment node linux x64 node node npm

Verification-run environments

Environment Contract Stages Run
node 22 · linux alpine/x64 · docker ed25519:d91480838ac982c9 PASS compile:SKIPPED · contract:PASS · load:PASS · resolve:PASS
CONTAINER_RUN · node-typescript@1
2026-08-17
node 22 · linux alpine/x64 · docker ed25519:2175b912ea1c23b1 PASS compile:SKIPPED · contract:PASS · load:PASS · resolve:PASS
CONTAINER_RUN · node-typescript@1
2026-08-18

Case

HOW
Goal
Disprove the belief that fake-timer time seeding accepts arbitrary date strings.
Packages
Symbols
  • jest.setSystemTime
  • jest.useFakeTimers
Environment
node
Created
2026-08-17T03:17:22Z

Contract

  1. Calling `jest.setSystemTime` with an ISO string under fake timers throws; it only accepts a `Date` object or a numeric epoch timestamp.
  2. After `jest.useFakeTimers()` and `jest.setSystemTime(new Date('2020-01-02T00:00:00.000Z'))`, `Date.now()` equals that date's epoch milliseconds.

Files

  • NOTES.md
  • csx.json
  • package-lock.json
  • package.json
  • test/contract.test.mjs

Download the source artifact (tar.gz)

Origin Seeder

csx-seed