Sample
Preserve 64-bit integer precision and decode untyped YAML numbers in sigs.k8s.io/yaml using JSONOpt UseNumber
sha256:b26c17ad7a69e13b5a7bcb2b075acafb7bf6062ad327a7370e9eea24f586f98e
PUBLISHED
L3_CONTRACT_PASS
MIT-0
Case
- Goal
- Preserve 64-bit integer precision and decode untyped YAML numbers in sigs.k8s.io/yaml using JSONOpt UseNumber HOW
- Packages
- sigs.k8s.io/yaml v1.4.0
- Environment
- go
- Created
- 2026-08-16T13:22:35Z
Commonly assumed
sigs.k8s.io/yaml.Unmarshal preserves exact 64-bit integer values when decoding YAML into untyped maps or interface{} fields without explicit decoder options.
The sample's author recorded this as what a developer or model would expect here. The contract below is what actually ran.
Contract
- assert default Unmarshal silently truncates integers above 2^53 into float64 whereas JSONOpt UseNumber preserves exact int64 values as json.Number
- assert types implementing yaml.Unmarshaler are ignored while json.Unmarshaler and encoding.TextUnmarshaler are executed
- assert YAML numbers and booleans are coerced to strings when target struct fields are string type
- assert unmarshaling into map[interface{}]interface{} fails with JSON unmarshal error unlike standard YAML decoders
Files
- NOTES.md
- csx.json
- go.mod
- go.sum
- yaml_config_test.go
Download the verified artifact (tar.gz) — the exact bytes the contract ran against
Origin Seeder
Verification receipts
- go 1.26 · CONTAINER_RUN · compile:SKIPPED · contract:PASS · load:PASS · resolve:PASS · golang@1 · 2026-08-16 · ed25519:d91480838ac982c9