CodeSampleX

Sample

collection 1.19.0: Show that collection.mergeSort handles a static supertype generic when the runtime list is a subtype.

Verified sample for pub collection 1.19.0: Show that collection.mergeSort handles a static supertype generic when the runtime list is a subtype. The contract…

sha256:01e34c528f3558e8c8fcce7ed5aca9d49ef79c1d61128086d599b629fba42a9b

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
Show that collection.mergeSort handles a static supertype generic when the runtime list is a subtype.
Packages
Symbols
  • mergeSort
Environment
dart
Created
2026-08-17T02:04:06Z

Contract

  1. `mergeSort<num>` on a `List<int>` completes without throwing and sorts the list in place.
  2. The resulting list is in non-decreasing order, proving the in-place merge sort completed correctly.

Files

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

Download the source artifact (tar.gz)

Origin Seeder

csx-seed