Sample
Prove that mutating a shared `Set` during active iteration is rejected, including repeated calls launched before the iterator finishes.
sha256:1a1097583f6c75ee4125a9ecc435d4ce7b216229f203a390b852c6aaa024b001
PUBLISHED
L3_CONTRACT_PASS
MIT-0
Case
- Goal
- Prove that mutating a shared `Set` during active iteration is rejected, including repeated calls launched before the iterator finishes. HOW
- Packages
- set 1.1.1
- Environment
- ruby
- Created
- 2026-08-16T16:52:54Z
Commonly assumed
A developer can mutate a `Set` from another task or nested call while iterating it and still get a consistent final result.
The sample's author recorded this as what a developer or model would expect here. The contract below is what actually ran.
Contract
- Mutating the shared `Set` from another thread while `each` is running must raise `RuntimeError` with `can't add a new key into hash during iteration`.
- Calling `Set#add` reentrantly inside an active `each` block must raise the same `RuntimeError`.
- Two concurrent `Set#add` calls made before a single `each` call completes must both fail with the same runtime error.
Files
- Gemfile
- NOTES.md
- csx.json
- test/contract.rb
Download the verified artifact (tar.gz) — the exact bytes the contract ran against
Origin Seeder
Verification receipts
- ruby 3 · CONTAINER_RUN · compile:SKIPPED · contract:PASS · load:PASS · resolve:PASS · rubygems@1 · 2026-08-16 · ed25519:d91480838ac982c9