CodeSampleX

Sample

verify pkg:npm/hasown@2.0.4

sha256:c886ab294bb3afe864b94927cf821cc736b627449a5bc3a9ae3c326afa5e51dd

Publication state. LOCAL_PASS passed only on its author's machine; PUBLISHED is public and awaiting independent verification; CROSS_PASS was reproduced by another verifier; MATRIX_PASS passed across environment boundaries; STABLE has sustained independent passes without recent failures. Evidence strength. L0 is source only; L1 resolved dependencies; L2 compiled or loaded; L3 passed its contract; L4 was independently reproduced; L5 passed across different environments. MIT-0

Execution evidence

Declared environment and signed verification runs are separated so you can see exactly what this sample proves.

Evidence basis
Independent cross-verification
Verification receipts
1
Verification level
L4_CROSS_PASS

Declared environment

Execution context
node 22
Operating system
linux
Architecture
x64
Runtime
node 22
Language
javascript
Package manager
npm 10

Verification-run environments

node 22 · linux alpine/x64 · docker PASS
Execution context
node 22
Operating system
linux alpine · musl
Architecture
x64
Runtime
node 22
Language
javascript
Package manager
npm
Execution
container · docker

CONTAINER_RUN · compile:SKIPPED · contract:PASS · load:PASS · resolve:PASS · node-typescript@1 · 2026-08-19

Case

HOW
Goal
verify pkg:npm/hasown@2.0.4
Packages
Symbols
  • hasOwn
Environment
node 22
Created
2026-08-18T17:58:24Z

Contract

  1. hasOwn returns true for direct own properties on plain objects including undefined and null values
  2. hasOwn returns false for inherited prototype properties like toString and valueOf
  3. hasOwn returns true for valid array indices and length property while returning false for out of bounds indices and array prototype methods
  4. hasOwn works correctly on objects created with Object.create(null) lacking Object prototype methods
  5. hasOwn correctly identifies properties on objects where hasOwnProperty is shadowed or overridden
  6. hasOwn returns true for properties with falsy values such as false, empty string, and zero
  7. hasOwn supports Symbol properties when Symbol is available in the environment

Files

  • PROMPT.md
  • csx.json
  • index.js
  • package-lock.json
  • package.json
  • spec.json
  • test/contract.js

Download the source artifact (tar.gz)

Origin Seeder

anonymous

Verification receipts

  • node 22 · linux alpine/x64 · docker PASS
    CONTAINER_RUN compile:SKIPPED · contract:PASS · load:PASS · resolve:PASS node-typescript@1
    ed25519:2175b912ea1c23b1