@vitest/utils 4.1.10: toArray

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.toArray 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.toArray

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:a58502314bde199085b4fa9cdb07e0a29cebb7a2a63945a351319764f90b8dbd","contract":["toArray converts nullish values (null and undefined) into empty arrays","toArray returns the same array instance unchanged when given an array","toArray wraps primitive values into single-element arrays","toArray wraps non-nullish object structures into single-element arrays","ensureArray and normalizeItems wrap items and flatten multiple arguments using toArray"],"goal":"verify @vitest/utils.toArray in pkg:npm/%40vitest/utils@4.1.10","kind":"HOW","packages":["pkg:npm/%40vitest/utils@4.1.10"],"schemaVersion":1,"symbols":["@vitest/utils.toArray"]},"contractCommand":["node","test/contract.mjs"],"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/%40vitest/utils@4.1.10"],"schemaVersion":1,"subject":"pkg:npm/%40vitest/utils@4.1.10","symbols":["@vitest/utils.toArray"],"verifierAdapter":"node-typescript@1"}

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

export { toArray };

export function ensureArray(value) {
  return toArray(value);
}

export function normalizeItems(...items) {
  return items.flatMap((item) => toArray(item));
}

{
  "name": "sample-vitest-utils-to-array",
  "version": "1.0.0",
  "lockfileVersion": 3,
  "requires": true,
  "packages": {
    "": {
      "name": "sample-vitest-utils-to-array",
      "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-to-array",
  "version": "1.0.0",
  "description": "Clean-room verification sample for @vitest/utils toArray",
  "type": "module",
  "main": "index.mjs",
  "scripts": {
    "test": "node test/contract.mjs"
  },
  "dependencies": {
    "@vitest/utils": "4.1.10"
  }
}

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

import assert from 'node:assert/strict';
import { toArray } from '@vitest/utils/helpers';
import { ensureArray, normalizeItems } from '../index.mjs';

// 1. toArray converts nullish values (null and undefined) into empty arrays
{
  assert.deepEqual(toArray(null), []);
  assert.deepEqual(toArray(undefined), []);
}

// 2. toArray returns the same array instance unchanged when given an array
{
  const empty = [];
  assert.equal(toArray(empty), empty);

  const arr = [1, 2, 'three'];
  assert.equal(toArray(arr), arr);
  assert.deepEqual(toArray(arr), [1, 2, 'three']);
}

// 3. toArray wraps primitive values into single-element arrays
{
  assert.deepEqual(toArray('hello'), ['hello']);
  assert.deepEqual(toArray(''), ['']);
  assert.deepEqual(toArray(42), [42]);
  assert.deepEqual(toArray(0), [0]);
  assert.deepEqual(toArray(true), [true]);
  assert.deepEqual(toArray(false), [false]);
  assert.deepEqual(toArray(100n), [100n]);
  const sym = Symbol('token');
  assert.deepEqual(toArray(sym), [sym]);
}

// 4. toArray wraps non-nullish object structures into single-element arrays
{
  const obj = { key: 'value' };
  assert.deepEqual(toArray(obj), [obj]);

  const date = new Date(0);
  assert.deepEqual(toArray(date), [date]);

  const fn = () => {};
  assert.deepEqual(toArray(fn), [fn]);

  const regex = /pattern/;
  assert.deepEqual(toArray(regex), [regex]);
}

// 5. ensureArray and normalizeItems wrap items and flatten multiple arguments using toArray
{
  assert.deepEqual(ensureArray(null), []);
  assert.deepEqual(ensureArray('single'), ['single']);
  assert.deepEqual(normalizeItems(1, [2, 3], null, 'foo', undefined), [1, 2, 3, 'foo']);
}