Sample
anyio 4.13.0: Catching child task exceptions directly with standard except clauses fails because AnyIO task groups bundle all failures into ExceptionGroup while cancelling unshielded sibling scopes
Verified sample for pypi anyio 4.13.0: Catching child task exceptions directly with standard except clauses fails because AnyIO task groups bundle all…
sha256:cd38816f1ccfec33debc67126f06dfc62308c2f87ebc872b19f3eebea5cd2d9f
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
python linux x64 python python pip
Verification-run environments
| Environment | Contract | Stages | Run |
|---|---|---|---|
| python 3.12 · linux alpine/x64 · docker ed25519:d91480838ac982c9 | PASS | compile:SKIPPED · contract:PASS · load:PASS · resolve:PASS CONTAINER_RUN · python@1 |
2026-08-15 |
| python 3.12 · linux alpine/x64 · docker ed25519:2175b912ea1c23b1 | PASS | compile:SKIPPED · contract:PASS · load:PASS · resolve:PASS CONTAINER_RUN · python@1 |
2026-08-18 |
Case
HOW- Goal
- Catching child task exceptions directly with standard except clauses fails because AnyIO task groups bundle all failures into ExceptionGroup while cancelling unshielded sibling scopes
- Packages
- Symbols
-
- anyio.create_task_group
- anyio.CancelScope
- anyio.get_cancelled_exc_class
- Environment
- python
- Created
- 2026-08-15T17:09:08Z
Contract
- assert not raw_caught, 'Direct except ValueError must not catch TaskGroup exception'
- assert group_caught, 'Caller must catch ExceptionGroup / BaseExceptionGroup'
- assert unshielded_failed, 'Unshielded async operation during cancellation must raise CancelledError'
- assert c_shielded_scope_survived, 'Active shielded scope entered before failure survives TaskGroup cancellation'
Files
- NOTES.md
- csx.json
- requirements.txt
- test/contract.py