@vitest/utils 4.1.10: isObject

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 @vitest/utils.isObject in pkg:npm/%40vitest/utils@4.1.10
Kind: HOW

Use EXACTLY these public packages and versions:
  - pkg:npm/%40vitest/utils@4.1.10
Demonstrate these symbols/APIs:
  - @vitest/utils.isObject

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:sha256:30116fe1c809f9800b72ce8b8b33d359148f0c7ad7e5fd25c447c874dcc3aeda","contract":["isObject returns true for plain objects and objects created with Object.create(null)","isObject returns true for complex object instances including Date, RegExp, Map, and Set","isObject returns false for arrays","isObject returns false for null and undefined","isObject returns false for primitive types including strings, numbers, booleans, symbols, and bigints","isObject returns false for functions"],"goal":"verify @vitest/utils.isObject in pkg:npm/%40vitest/utils@4.1.10","kind":"HOW","packages":["pkg:npm/%40vitest/utils@4.1.10"],"schemaVersion":1,"symbols":["@vitest/utils.isObject"]},"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/%40vitest/utils@4.1.10"],"schemaVersion":1,"subject":"pkg:npm/%40vitest/utils@4.1.10","symbols":["@vitest/utils.isObject"],"verifierAdapter":"node-typescript@1"}

import { isObject } from '@vitest/utils/helpers';

export { isObject };

export function checkIsObject(val) {
  return isObject(val);
}

{
  "name": "sample-vitest-utils-isobject",
  "version": "1.0.0",
  "lockfileVersion": 3,
  "requires": true,
  "packages": {
    "": {
      "name": "sample-vitest-utils-isobject",
      "version": "1.0.0",
      "dependencies": {
        "@vitest/utils": "4.1.10"
      }
    },
    "node_modules/@vitest/pretty-format": {
      "version": "4.1.10",
      "resolved": "https://registry.npmjs.org/@vitest/pretty-format/-/pretty-format-4.1.10.tgz",
      "integrity": "sha512-W1HsjSH4MXQ9YfmmhLAoIYf1HRfekQCGngeIgcei6MP5QQGWUe0gkopdZQaVCFO+JDJMrAJGwa5pRpNpvy4P8Q==",
      "license": "MIT",
      "dependencies": {
        "tinyrainbow": "^3.1.0"
      },
      "funding": {
        "url": "https://opencollective.com/vitest"
      }
    },
    "node_modules/@vitest/utils": {
      "version": "4.1.10",
      "resolved": "https://registry.npmjs.org/@vitest/utils/-/utils-4.1.10.tgz",
      "integrity": "sha512-fy9am/HWxbaGt/Sawrp90vt6Y6jQwf1RX77cz3uwoJwJVMli/e1IEwRPnMNJ7vKfPTwo0diXifkpPvwH9v7nGA==",
      "license": "MIT",
      "dependencies": {
        "@vitest/pretty-format": "4.1.10",
        "convert-source-map": "^2.0.0",
        "tinyrainbow": "^3.1.0"
      },
      "funding": {
        "url": "https://opencollective.com/vitest"
      }
    },
    "node_modules/convert-source-map": {
      "version": "2.0.0",
      "resolved": "https://registry.npmjs.org/convert-source-map/-/convert-source-map-2.0.0.tgz",
      "integrity": "sha512-Kvp459HrV2FEJ1CAsi1Ku+MY3kasH19TFykTz2xWmMeq6bk2NU3XXvfJ+Q61m0xktWwt+1HSYf3JZsTms3aRJg==",
      "license": "MIT"
    },
    "node_modules/tinyrainbow": {
      "version": "3.1.1",
      "resolved": "https://registry.npmjs.org/tinyrainbow/-/tinyrainbow-3.1.1.tgz",
      "integrity": "sha512-yau8yJdTt989Mm0Bd/236QnzEiPf2xLLTqUZRUJOo/3CB078LSwzei343DgtJVmfJKJE3TMINY1u42SQsP6mXw==",
      "license": "MIT",
      "engines": {
        "node": ">=14.0.0"
      }
    }
  }
}

{
  "name": "sample-vitest-utils-isobject",
  "version": "1.0.0",
  "type": "module",
  "main": "index.mjs",
  "scripts": {
    "test": "node test/contract.mjs"
  },
  "dependencies": {
    "@vitest/utils": "4.1.10"
  }
}

{
  "schemaVersion": 1,
  "goal": "verify @vitest/utils.isObject in pkg:npm/%40vitest/utils@4.1.10",
  "kind": "HOW",
  "packages": [
    "pkg:npm/%40vitest/utils@4.1.10"
  ],
  "symbols": [
    "@vitest/utils.isObject"
  ]
}

import assert from 'node:assert/strict';
import { isObject } from '@vitest/utils/helpers';
import { checkIsObject } from '../index.mjs';

// 1. isObject returns true for plain objects and objects created with Object.create(null)
{
  assert.equal(isObject({}), true);
  assert.equal(isObject({ key: 'value', nested: { a: 1 } }), true);
  assert.equal(isObject(Object.create(null)), true);
  assert.equal(checkIsObject({}), true);
  assert.equal(checkIsObject(Object.create(null)), true);
}

// 2. isObject returns true for complex object instances including Date, RegExp, Map, and Set
{
  assert.equal(isObject(new Date()), true);
  assert.equal(isObject(/test-pattern/i), true);
  assert.equal(isObject(new Map()), true);
  assert.equal(isObject(new Set()), true);
  assert.equal(isObject(new (class CustomEntity {})()), true);
  assert.equal(checkIsObject(new Date()), true);
}

// 3. isObject returns false for arrays
{
  assert.equal(isObject([]), false);
  assert.equal(isObject([1, 2, 3]), false);
  assert.equal(isObject(new Array(5)), false);
  assert.equal(checkIsObject([]), false);
  assert.equal(checkIsObject([1, 2, 3]), false);
}

// 4. isObject returns false for null and undefined
{
  assert.equal(isObject(null), false);
  assert.equal(isObject(undefined), false);
  assert.equal(checkIsObject(null), false);
  assert.equal(checkIsObject(undefined), false);
}

// 5. isObject returns false for primitive types including strings, numbers, booleans, symbols, and bigints
{
  assert.equal(isObject('string'), false);
  assert.equal(isObject(''), false);
  assert.equal(isObject(42), false);
  assert.equal(isObject(0), false);
  assert.equal(isObject(NaN), false);
  assert.equal(isObject(true), false);
  assert.equal(isObject(false), false);
  assert.equal(isObject(Symbol('id')), false);
  assert.equal(isObject(100n), false);
  assert.equal(checkIsObject('string'), false);
  assert.equal(checkIsObject(42), false);
  assert.equal(checkIsObject(true), false);
}

// 6. isObject returns false for functions
{
  assert.equal(isObject(() => {}), false);
  assert.equal(isObject(function regularFn() {}), false);
  assert.equal(isObject(class ClassDeclaration {}), false);
  assert.equal(checkIsObject(() => {}), false);
}

console.log('All @vitest/utils isObject contract assertions passed.');