isarray 1.0.0: isarray

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 isarray in pkg:npm/isarray@1.0.0
Kind: HOW

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

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:sha256:088d256d9cca85706d38d746ce58b27788eb8f9f189137bf346cacfa2eb84280","contract":["isarray returns true for array literals and Array instances","isarray returns false for non-array primitive values","isarray returns false for plain objects and functions","isarray returns false for array-like objects and arguments","isarray returns false for TypedArray instances"],"goal":"verify isarray in pkg:npm/isarray@1.0.0","kind":"HOW","packages":["pkg:npm/isarray@1.0.0"],"schemaVersion":1,"symbols":["isarray"]},"contractCommand":["node","test/contract.mjs"],"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","symbols":["isarray"],"verifierAdapter":"node-typescript@1"}

{
  "name": "isarray-sample",
  "version": "1.0.0",
  "lockfileVersion": 3,
  "requires": true,
  "packages": {
    "": {
      "name": "isarray-sample",
      "version": "1.0.0",
      "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": "isarray-sample",
  "version": "1.0.0",
  "private": true,
  "description": "Clean-room verification for isarray",
  "dependencies": {
    "isarray": "1.0.0"
  }
}

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

import assert from 'node:assert';
import isarray from 'isarray';

// 1. isarray returns true for array literals and Array instances
assert.strictEqual(isarray([]), true);
assert.strictEqual(isarray([1, 2, 3]), true);
assert.strictEqual(isarray(new Array()), true);
assert.strictEqual(isarray(new Array(5)), true);

// 2. isarray returns false for non-array primitive values
assert.strictEqual(isarray(null), false);
assert.strictEqual(isarray(undefined), false);
assert.strictEqual(isarray(0), false);
assert.strictEqual(isarray(42), false);
assert.strictEqual(isarray('string'), false);
assert.strictEqual(isarray(true), false);
assert.strictEqual(isarray(false), false);
assert.strictEqual(isarray(Symbol('sym')), false);
assert.strictEqual(isarray(10n), false);

// 3. isarray returns false for plain objects and functions
assert.strictEqual(isarray({}), false);
assert.strictEqual(isarray({ a: 1, b: 2 }), false);
assert.strictEqual(isarray(function () {}), false);
assert.strictEqual(isarray(() => {}), false);
assert.strictEqual(isarray(/regex/), false);
assert.strictEqual(isarray(new Date()), false);

// 4. isarray returns false for array-like objects and arguments
const args = (function () { return arguments; })(1, 2, 3);
assert.strictEqual(isarray(args), false);
assert.strictEqual(isarray({ length: 0 }), false);
assert.strictEqual(isarray({ 0: 'a', 1: 'b', length: 2 }), false);

// 5. isarray returns false for TypedArray instances
assert.strictEqual(isarray(new Uint8Array(8)), false);
assert.strictEqual(isarray(new Int32Array(4)), false);
assert.strictEqual(isarray(new Float64Array(2)), false);

console.log('Contract passed');