has-property-descriptors 1.0.2

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/has-property-descriptors@1.0.2
Kind: HOW

Use EXACTLY these public packages and versions:
  - pkg:npm/has-property-descriptors@1.0.2

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:df993cc100679d030c0611a99afdd835be899e1313315a0ab250231527384c77","contract":["hasPropertyDescriptors returns true when Object.defineProperty is supported in the JavaScript environment","hasPropertyDescriptors.hasArrayLengthDefineBug returns false in modern Node.js where array length definition is supported without bugs","defineSafeProperty defines non-writable and non-enumerable properties using property descriptors when supported"],"goal":"verify pkg:npm/has-property-descriptors@1.0.2","kind":"HOW","packages":["pkg:npm/has-property-descriptors@1.0.2"],"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","runtime":"node","runtimeVersion":"22.23.2","schemaVersion":1},"license":"MIT-0","packages":["pkg:npm/has-property-descriptors@1.0.2"],"schemaVersion":1,"subject":"pkg:npm/has-property-descriptors@1.0.2","verifierAdapter":"node-typescript@1"}

'use strict';

const hasPropertyDescriptors = require('has-property-descriptors');

/**
 * Checks if the current runtime environment supports property descriptors.
 * @returns {boolean} True if Object.defineProperty is supported.
 */
function supportsPropertyDescriptors() {
  return hasPropertyDescriptors();
}

/**
 * Checks if the environment has the array length define bug.
 * @returns {boolean|null} False in modern environments, true if bug is present, null if defineProperty is absent.
 */
function checkArrayLengthBug() {
  return hasPropertyDescriptors.hasArrayLengthDefineBug();
}

/**
 * Defines a property on an object if supported.
 * @param {Object} obj Target object.
 * @param {string|symbol} prop Property key.
 * @param {Object} descriptor Property descriptor.
 * @returns {boolean} True if defined using descriptors, false otherwise.
 */
function defineSafeProperty(obj, prop, descriptor) {
  if (hasPropertyDescriptors()) {
    Object.defineProperty(obj, prop, descriptor);
    return true;
  }
  obj[prop] = descriptor.value;
  return false;
}

module.exports = {
  hasPropertyDescriptors,
  supportsPropertyDescriptors,
  checkArrayLengthBug,
  defineSafeProperty
};

{
  "name": "sample-has-property-descriptors",
  "version": "1.0.0",
  "lockfileVersion": 3,
  "requires": true,
  "packages": {
    "": {
      "name": "sample-has-property-descriptors",
      "version": "1.0.0",
      "dependencies": {
        "has-property-descriptors": "1.0.2"
      }
    },
    "node_modules/es-define-property": {
      "version": "1.0.1",
      "resolved": "https://registry.npmjs.org/es-define-property/-/es-define-property-1.0.1.tgz",
      "integrity": "sha512-e3nRfgfUZ4rNGL232gUgX06QNyyez04KdjFrF+LTRoOXmrOgFKDg4BCdsjW8EnT69eqdYGmRpJwiPVYNrCaW3g==",
      "license": "MIT",
      "engines": {
        "node": ">= 0.4"
      }
    },
    "node_modules/has-property-descriptors": {
      "version": "1.0.2",
      "resolved": "https://registry.npmjs.org/has-property-descriptors/-/has-property-descriptors-1.0.2.tgz",
      "integrity": "sha512-55JNKuIW+vq4Ke1BjOTjM2YctQIvCT7GFzHwmfZPGo5wnrgkid0YQtnAleFSqumZm4az3n2BS+erby5ipJdgrg==",
      "license": "MIT",
      "dependencies": {
        "es-define-property": "^1.0.0"
      },
      "funding": {
        "url": "https://github.com/sponsors/ljharb"
      }
    }
  }
}

{
  "name": "sample-has-property-descriptors",
  "version": "1.0.0",
  "private": true,
  "description": "Clean-room verification of has-property-descriptors",
  "dependencies": {
    "has-property-descriptors": "1.0.2"
  }
}

{
  "schemaVersion": 1,
  "goal": "verify pkg:npm/has-property-descriptors@1.0.2",
  "kind": "HOW",
  "packages": [
    "pkg:npm/has-property-descriptors@1.0.2"
  ]
}

'use strict';

const assert = require('node:assert/strict');
const hasPropertyDescriptors = require('has-property-descriptors');
const {
  supportsPropertyDescriptors,
  checkArrayLengthBug,
  defineSafeProperty
} = require('../index.cjs');

assert.equal(typeof hasPropertyDescriptors, 'function', 'has-property-descriptors must export a function');
assert.equal(typeof hasPropertyDescriptors.hasArrayLengthDefineBug, 'function', 'hasArrayLengthDefineBug must be a function');

const supported = supportsPropertyDescriptors();
assert.equal(typeof supported, 'boolean', 'supportsPropertyDescriptors must return a boolean');
assert.equal(supported, true, 'hasPropertyDescriptors must return true in Node.js');

const hasBug = checkArrayLengthBug();
assert.equal(typeof hasBug, 'boolean', 'checkArrayLengthBug must return a boolean in Node.js');
assert.equal(hasBug, false, 'hasArrayLengthDefineBug must return false in modern Node.js');

const target = {};
const defined = defineSafeProperty(target, 'testProp', {
  value: 42,
  writable: false,
  enumerable: false,
  configurable: true
});

assert.equal(defined, true, 'defineSafeProperty must return true when descriptors are supported');
assert.equal(target.testProp, 42, 'target property value must match descriptor value');

const desc = Object.getOwnPropertyDescriptor(target, 'testProp');
assert.ok(desc, 'property descriptor must exist');
assert.equal(desc.value, 42, 'descriptor value must be 42');
assert.equal(desc.writable, false, 'descriptor writable must be false');
assert.equal(desc.enumerable, false, 'descriptor enumerable must be false');
assert.equal(desc.configurable, true, 'descriptor configurable must be true');

// Verify non-writable behavior in strict mode
assert.throws(() => {
  'use strict';
  target.testProp = 99;
}, TypeError, 'modifying a non-writable property in strict mode must throw TypeError');

console.log('Contract test passed.');