safe-stable-stringify 2.5.0

Clean-room public code sample — generation instructions

Write a brand-new, minimal, self-contained code sample in this clean-room directory.
Do not copy, paraphrase, or reference any existing project source. Work only from this spec.

A csx.json manifest scaffold already exists. Do not recreate it from memory. Preserve its case.goal, packages and symbols; fill its empty case.contract with exact assertions and correct its environment, commands and verifierAdapter for the files you generate.

Goal: verify pkg:npm/safe-stable-stringify@2.5.0
Kind: HOW

Use EXACTLY these public packages and versions:
  - pkg:npm/safe-stable-stringify@2.5.0
Constraints:
  - executionContext: node
Required runtime conditions:
  - ecosystem: npm
  - language: javascript
  - moduleSystem: cjs
  - packageManager: npm@10.9.8
  - runtime: node@22.23.2

Rules:
  - One focused purpose; the smallest project that proves the goal.
  - Include a contract test (test/contract.*) that runs OFFLINE and exits 0 exactly when the goal behavior works.
  - Pin every dependency with a lockfile so resolution is reproducible.
  - No secrets, credentials, or tokens. No real URLs (only example.com or localhost). No absolute paths.
  - No personal names, emails, company names, or project identifiers of any kind.
  - No binaries and no generated output (node_modules, dist, target, venv, .git, .env).
  - Keep it under 200 files and 256KB packed.

{"case":{"caseId":"case:sha256:976626b8c22941eb63262a7cdac057c99e2c23cdd161e0014839f006313a4e4c","constraints":{"executionContext":"node"},"contract":["stringify serializes objects with deterministically sorted keys","stringify safely serializes circular references using default [Circular] marker","stringify serializes BigInt values as numbers without throwing TypeError","stringify supports custom replacer functions and space indentation formatting","stringify.configure creates a custom stringifier with configurable circularValue behavior"],"goal":"verify pkg:npm/safe-stable-stringify@2.5.0","kind":"HOW","packages":["pkg:npm/safe-stable-stringify@2.5.0"],"schemaVersion":1},"contractCommand":["node","test/contract.cjs"],"environment":{"arch":"x64","distro":"ubuntu","ecosystem":"npm","executionContext":"node","language":"javascript","libc":"glibc","libcVersion":"2.39","moduleSystem":"cjs","os":"linux","osVersionBucket":"24","packageManager":"npm","packageManagerVersion":"10.9.8","runtime":"node","runtimeVersion":"22.23.2","schemaVersion":1},"license":"MIT-0","packages":["pkg:npm/safe-stable-stringify@2.5.0"],"schemaVersion":1,"subject":"pkg:npm/safe-stable-stringify@2.5.0","verifierAdapter":"node-typescript@1"}

{
  "name": "sample-safe-stable-stringify",
  "version": "1.0.0",
  "lockfileVersion": 3,
  "requires": true,
  "packages": {
    "": {
      "name": "sample-safe-stable-stringify",
      "version": "1.0.0",
      "license": "MIT-0",
      "dependencies": {
        "safe-stable-stringify": "2.5.0"
      }
    },
    "node_modules/safe-stable-stringify": {
      "version": "2.5.0",
      "resolved": "https://registry.npmjs.org/safe-stable-stringify/-/safe-stable-stringify-2.5.0.tgz",
      "integrity": "sha512-b3rppTKm9T+PsVCBEOUR46GWI7fdOs00VKZ1+9c1EWDaDMvjQc6tUwuFyIprgGgTcWoVHSKrU8H31ZHA2e0RHA==",
      "license": "MIT",
      "engines": {
        "node": ">=10"
      }
    }
  }
}

{
  "name": "sample-safe-stable-stringify",
  "version": "1.0.0",
  "private": true,
  "license": "MIT-0",
  "dependencies": {
    "safe-stable-stringify": "2.5.0"
  }
}

{
  "schemaVersion": 1,
  "goal": "verify pkg:npm/safe-stable-stringify@2.5.0",
  "kind": "HOW",
  "packages": [
    "pkg:npm/safe-stable-stringify@2.5.0"
  ],
  "constraints": {
    "executionContext": "node"
  },
  "runtimeConditions": {
    "ecosystem": "npm",
    "language": "javascript",
    "moduleSystem": "cjs",
    "packageManager": "npm@10.9.8",
    "runtime": "node@22.23.2"
  }
}

const assert = require('node:assert');
const stringify = require('safe-stable-stringify');
const { configure } = stringify;

// 1. stringify serializes objects with deterministically sorted keys
const unordered = { z: 10, a: 20, m: 30 };
const sorted = stringify(unordered);
assert.strictEqual(sorted, '{"a":20,"m":30,"z":10}');

// 2. stringify safely serializes circular references using default [Circular] marker
const circularObj = { name: 'cycle-test' };
circularObj.self = circularObj;
const circularResult = stringify(circularObj);
assert.strictEqual(circularResult, '{"name":"cycle-test","self":"[Circular]"}');

// 3. stringify serializes BigInt values as numbers without throwing TypeError
const bigIntObj = { count: 9007199254740993n };
const bigIntResult = stringify(bigIntObj);
assert.strictEqual(bigIntResult, '{"count":9007199254740993}');

// 4. stringify supports custom replacer functions and space indentation formatting
const objWithReplacer = { hide: 'secret', visible: 'ok' };
const formatted = stringify(
  objWithReplacer,
  (key, value) => (key === 'hide' ? undefined : value),
  2
);
assert.strictEqual(formatted, '{\n  "visible": "ok"\n}');

// 5. stringify.configure creates a custom stringifier with configurable circularValue behavior
const customStringify = configure({ circularValue: '[CustomCycle]' });
const customCircularObj = { id: 1 };
customCircularObj.self = customCircularObj;
const customResult = customStringify(customCircularObj);
assert.strictEqual(customResult, '{"id":1,"self":"[CustomCycle]"}');

const omitCircularStringify = configure({ circularValue: undefined });
const omitResult = omitCircularStringify(customCircularObj);
assert.strictEqual(omitResult, '{"id":1}');

console.log('Contract passed');