CodeSampleX

Sample

crypto 3.0.7: Prevent accidental corruption of a package:crypto Digest when accessing its bytes

Verified sample for pub crypto 3.0.7: Prevent accidental corruption of a package:crypto Digest when accessing its bytes. The contract ran on dart 3 · linux…

sha256:37417f5369d0f1097efea2a84bac724b25fa4e4acffbd1991b19bea3c3fa5748

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 dart linux x64 dart dart pub

Verification-run environments

Environment Contract Stages Run
dart 3 · linux debian/x64 · docker ed25519:d91480838ac982c9 PASS compile:SKIPPED · contract:PASS · load:PASS · resolve:PASS
CONTAINER_RUN · pub@1
2026-08-17
dart 3 · linux debian/x64 · docker ed25519:2175b912ea1c23b1 PASS compile:SKIPPED · contract:PASS · load:PASS · resolve:PASS
CONTAINER_RUN · pub@1
2026-08-18

Case

HOW
Goal
Prevent accidental corruption of a package:crypto Digest when accessing its bytes
Packages
Symbols
  • Digest.bytes
  • Hash.convert
Environment
dart
Created
2026-08-17T02:06:52Z

Contract

  1. if (hash.toString() == originalHex) throw Exception('Digest.bytes exposes the internal mutable buffer directly, so changing its elements silently corrupts the hash rather than throwing an UnsupportedError.');
  2. try { hash.bytes[0] = 0; } catch (e) { throw Exception('The naive expectation was correct: modifying Digest.bytes threw $e'); }

Files

  • NOTES.md
  • csx.json
  • pubspec.lock
  • pubspec.yaml
  • test/contract.dart

Download the source artifact (tar.gz)

Origin Seeder

csx-seed