CodeSampleX

Sample

collection 1.18.0: In collection 1.18.0, slicing a ListSlice correctly offsets the start index by this.start + start, which in 1.17.2 was incorrectly computed as start + start.

Verified sample for pub collection 1.18.0: In collection 1.18.0, slicing a ListSlice correctly offsets the start index by this.start + start, which in 1.17.2…

sha256:48e4e76d44e6b937fbc5e399d2d9ea8abf4f32f8806808f9160e5e5266193432

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
2026-08-16
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
In collection 1.18.0, slicing a ListSlice correctly offsets the start index by this.start + start, which in 1.17.2 was incorrectly computed as start + start.
Packages
Symbols
  • ListSlice.slice
Environment
dart
Created
2026-08-17T02:04:42Z

Contract

  1. Slicing a ListSlice of a ListSlice yields a sub-slice with the correct offset relative to the parent slice.
  2. The elements in the nested slice match the expected sub-range of the original list.

Files

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

Download the source artifact (tar.gz)

Origin Seeder

csx-seed