Sample
golang.org/x/sync 0.22.0: Handle singleflight duplicate suppression without persistent caching, shared flag propagation to leader and followers, in-flight Forget bypass, and panic propagation
Verified sample for golang golang.org/x/sync 0.22.0: Handle singleflight duplicate suppression without persistent caching, shared flag propagation to leader…
sha256:dd194e3340ff4f53b7309dbf639491071c00c853a8c56cc62ab1c74bc5f9f853
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
go linux x64 go go gomod
Verification-run environments
| Environment | Contract | Stages | Run |
|---|---|---|---|
| go 1.26 · linux alpine/x64 · docker ed25519:d91480838ac982c9 | PASS | compile:SKIPPED · contract:PASS · load:PASS · resolve:PASS CONTAINER_RUN · golang@1 |
2026-08-16 |
| go 1.26 · linux alpine/x64 · docker ed25519:2175b912ea1c23b1 | PASS | compile:SKIPPED · contract:PASS · load:PASS · resolve:PASS CONTAINER_RUN · golang@1 |
2026-08-18 |
Case
HOW- Goal
- Handle singleflight duplicate suppression without persistent caching, shared flag propagation to leader and followers, in-flight Forget bypass, and panic propagation
- Packages
- Symbols
-
- singleflight.Group
- Group.Do
- Group.DoChan
- Group.Forget
- Environment
- go
- Created
- 2026-08-16T12:24:20Z
Contract
- assert singleflight.Group executes sequential calls repeatedly without caching and does not require Forget to invalidate
- assert Do returns shared=true to both the leader goroutine and all joining duplicate callers
- assert calling Forget during an in-flight execution immediately allows new callers to spawn concurrent work without canceling the original execution
- assert a panic in the executed function is captured and re-panics with a panicError across all concurrent waiting callers
- assert concurrent callers receive references to the exact same pointer value in memory without deep copy or mutation isolation
Files
- NOTES.md
- csx.json
- go.mod
- go.sum
- singleflight_test.go