isarray 1.0.0

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/isarray@1.0.0
Kind: HOW

Use EXACTLY these public packages and versions:
  - pkg:npm/isarray@1.0.0

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:f49f60da968715126893d962ea98980224d8413ca464c656da4337d832947c54","contract":["isarray returns true for arrays and Array instances","isarray returns false for non-arrays including objects, arguments, strings, and primitives"],"goal":"verify pkg:npm/isarray@1.0.0","kind":"HOW","packages":["pkg:npm/isarray@1.0.0"],"schemaVersion":1},"contractCommand":["node","test/contract.js"],"environment":{"arch":"x64","distro":"ubuntu","ecosystem":"npm","libc":"glibc","libcVersion":"2.39","os":"linux","osVersionBucket":"24","packageManager":"npm","schemaVersion":1},"license":"MIT-0","packages":["pkg:npm/isarray@1.0.0"],"schemaVersion":1,"subject":"pkg:npm/isarray@1.0.0","verifierAdapter":"node-typescript@1"}

{
  "name": "sample-isarray",
  "version": "1.0.0",
  "lockfileVersion": 3,
  "requires": true,
  "packages": {
    "": {
      "name": "sample-isarray",
      "version": "1.0.0",
      "license": "MIT-0",
      "dependencies": {
        "isarray": "1.0.0"
      }
    },
    "node_modules/isarray": {
      "version": "1.0.0",
      "resolved": "https://registry.npmjs.org/isarray/-/isarray-1.0.0.tgz",
      "integrity": "sha512-VLghIWNM6ELQzo7zwmcg0NmTVyWKYjvIeM83yjp0wRDTmUnrM678fQbcKBo6n2CJEF0szoG//ytg+TKla89ALQ==",
      "license": "MIT"
    }
  }
}

{
  "name": "sample-isarray",
  "version": "1.0.0",
  "private": true,
  "description": "Clean-room verification sample for isarray",
  "main": "src/index.js",
  "scripts": {
    "test": "node test/contract.js"
  },
  "dependencies": {
    "isarray": "1.0.0"
  },
  "license": "MIT-0"
}

{
  "schemaVersion": 1,
  "goal": "verify pkg:npm/isarray@1.0.0",
  "kind": "HOW",
  "packages": [
    "pkg:npm/isarray@1.0.0"
  ]
}

const isarray = require('isarray');

function checkIsArray(value) {
  return isarray(value);
}

module.exports = {
  checkIsArray
};

const assert = require('node:assert');
const isarray = require('isarray');
const { checkIsArray } = require('../src/index.js');

// 1. Arrays return true
assert.strictEqual(isarray([]), true, 'empty array should return true');
assert.strictEqual(isarray([1, 2, 3]), true, 'number array should return true');
assert.strictEqual(isarray(['a', 'b']), true, 'string array should return true');
assert.strictEqual(isarray(new Array(5)), true, 'Array constructor should return true');
assert.strictEqual(isarray(Array.from({ length: 2 })), true, 'Array.from should return true');
assert.strictEqual(checkIsArray([10, 20]), true, 'checkIsArray wrapper should return true for array');

// 2. Non-arrays return false
assert.strictEqual(isarray(null), false, 'null should return false');
assert.strictEqual(isarray(undefined), false, 'undefined should return false');
assert.strictEqual(isarray(0), false, '0 should return false');
assert.strictEqual(isarray(123), false, 'number should return false');
assert.strictEqual(isarray(NaN), false, 'NaN should return false');
assert.strictEqual(isarray(Infinity), false, 'Infinity should return false');
assert.strictEqual(isarray(''), false, 'empty string should return false');
assert.strictEqual(isarray('hello'), false, 'string should return false');
assert.strictEqual(isarray(true), false, 'true should return false');
assert.strictEqual(isarray(false), false, 'false should return false');
assert.strictEqual(isarray({}), false, 'plain object should return false');
assert.strictEqual(isarray({ length: 0 }), false, 'array-like object should return false');
assert.strictEqual(isarray({ 0: 'a', length: 1 }), false, 'array-like object with elements should return false');
assert.strictEqual(isarray(() => {}), false, 'function should return false');
assert.strictEqual(isarray(Symbol('arr')), false, 'symbol should return false');
assert.strictEqual(isarray(/regex/), false, 'RegExp should return false');
assert.strictEqual(isarray(new Date()), false, 'Date should return false');

// arguments object is array-like but not an Array
(function () {
  assert.strictEqual(isarray(arguments), false, 'arguments object should return false');
})();

assert.strictEqual(checkIsArray({ notAnArray: true }), false, 'checkIsArray wrapper should return false for object');

console.log('Contract tests passed successfully.');