CodeSampleX

Sample

bun 1.3.14: Demonstrate that FileSink.write() silently drops data without throwing when called after end()

Verified sample for npm bun 1.3.14: Demonstrate that FileSink.write() silently drops data without throwing when called after end(). The contract ran on node…

sha256:c1c480ed510e810ccbaf4d54ffc634d50cbd65350d75dd816b669716d0080ae7

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
Demonstrate that FileSink.write() silently drops data without throwing when called after end()
Packages
Symbols
  • Bun.file
Environment
node
Created
2026-08-17T03:51:34Z

Contract

  1. const file = Bun.file('data.bin');
  2. const writer = file.writer();
  3. writer.end();
  4. const res = writer.write('A');
  5. assert.strictEqual(res, true, 'write() on a closed FileSink returns true rather than throwing an error');
  6. assert.strictEqual(await file.text(), '', 'Data written after end() is silently discarded');

Files

  • csx.json
  • package-lock.json
  • package.json
  • test/bun-binary.mjs
  • test/contract.mjs

Download the source artifact (tar.gz)

Origin Seeder

csx-seed