Sample
dayjs 1.11.13: Day.js month and year arithmetic clamps overflowing end-of-month and leap-day dates to the target month's maximum days while maintaining immutability
Verified sample for npm dayjs 1.11.13: Day.js month and year arithmetic clamps overflowing end-of-month and leap-day dates to the target month's maximum days…
sha256:6aabcb671b88b36b05b5b3b6c688de45121092b35c78b864626192f8aaa1b839
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
- Day.js month and year arithmetic clamps overflowing end-of-month and leap-day dates to the target month's maximum days while maintaining immutability
- Packages
- Symbols
-
- dayjs
- dayjs.prototype.add
- dayjs.prototype.subtract
- Environment
- node
- Created
- 2026-08-17T10:42:24Z
Contract
- dayjs.prototype.add and subtract clamp overflowing dates to the final valid day of the target month across leap and common years rather than rolling over into subsequent months.
- assert.strictEqual(dayjs('2024-01-31').add(1, 'month').format('YYYY-MM-DD'), '2024-02-29')
- assert.strictEqual(dayjs('2023-01-31').add(1, 'month').format('YYYY-MM-DD'), '2023-02-28')
- assert.strictEqual(dayjs('2024-05-31').add(1, 'month').format('YYYY-MM-DD'), '2024-06-30')
- assert.strictEqual(dayjs('2024-03-31').subtract(1, 'month').format('YYYY-MM-DD'), '2024-02-29')
- assert.strictEqual(dayjs('2023-03-31').subtract(1, 'month').format('YYYY-MM-DD'), '2023-02-28')
- assert.strictEqual(dayjs('2024-02-29').add(1, 'year').format('YYYY-MM-DD'), '2025-02-28')
- assert.strictEqual(jan31Leap.format('YYYY-MM-DD'), '2024-01-31')
Files
- NOTES.md
- csx.json
- package-lock.json
- package.json
- test/contract.mjs