@isaacs/brace-expansion 5.0.1

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/%40isaacs/brace-expansion@5.0.1
Kind: HOW

Use EXACTLY these public packages and versions:
  - pkg:npm/%40isaacs/brace-expansion@5.0.1

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:sha256:3552edaab03ba12ad3d0c9af2e8f482f42b14c23e8372c82266abb2e4275f7f5","contract":["expand expands comma-separated lists within curly braces into string arrays","expand expands numeric and alphabetical ranges including reverse and stepped sequences","expand supports nested brace expressions and Cartesian product combinations","expand handles zero-padded numeric sequences and custom max expansion limits","expand returns empty array for empty inputs and exports EXPANSION_MAX constant"],"goal":"verify pkg:npm/%40isaacs/brace-expansion@5.0.1","kind":"HOW","packages":["pkg:npm/%40isaacs/brace-expansion@5.0.1"],"schemaVersion":1},"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/%40isaacs/brace-expansion@5.0.1"],"schemaVersion":1,"subject":"pkg:npm/%40isaacs/brace-expansion@5.0.1","verifierAdapter":"node-typescript@1"}

{
  "name": "sample-brace-expansion",
  "version": "1.0.0",
  "lockfileVersion": 3,
  "requires": true,
  "packages": {
    "": {
      "name": "sample-brace-expansion",
      "version": "1.0.0",
      "license": "MIT-0",
      "dependencies": {
        "@isaacs/brace-expansion": "5.0.1"
      }
    },
    "node_modules/@isaacs/balanced-match": {
      "version": "4.0.1",
      "resolved": "https://registry.npmjs.org/@isaacs/balanced-match/-/balanced-match-4.0.1.tgz",
      "integrity": "sha512-yzMTt9lEb8Gv7zRioUilSglI0c0smZ9k5D65677DLWLtWJaXIS3CqcGyUFByYKlnUj6TkjLVs54fBl6+TiGQDQ==",
      "license": "MIT",
      "engines": {
        "node": "20 || >=22"
      }
    },
    "node_modules/@isaacs/brace-expansion": {
      "version": "5.0.1",
      "resolved": "https://registry.npmjs.org/@isaacs/brace-expansion/-/brace-expansion-5.0.1.tgz",
      "integrity": "sha512-WMz71T1JS624nWj2n2fnYAuPovhv7EUhk69R6i9dsVyzxt5eM3bjwvgk9L+APE1TRscGysAVMANkB0jh0LQZrQ==",
      "license": "MIT",
      "dependencies": {
        "@isaacs/balanced-match": "^4.0.1"
      },
      "engines": {
        "node": "20 || >=22"
      }
    }
  }
}

{
  "name": "sample-brace-expansion",
  "version": "1.0.0",
  "private": true,
  "description": "Clean-room verification of @isaacs/brace-expansion",
  "main": "src/index.js",
  "license": "MIT-0",
  "dependencies": {
    "@isaacs/brace-expansion": "5.0.1"
  }
}

{
  "schemaVersion": 1,
  "goal": "verify pkg:npm/%40isaacs/brace-expansion@5.0.1",
  "kind": "HOW",
  "packages": [
    "pkg:npm/%40isaacs/brace-expansion@5.0.1"
  ]
}

const { expand, EXPANSION_MAX } = require('@isaacs/brace-expansion');

/**
 * Expand a brace pattern into an array of string combinations.
 * @param {string} pattern - The bash-style brace expansion pattern
 * @param {object} [options] - Optional settings (e.g. { max: number })
 * @returns {string[]} Array of expanded strings
 */
function expandBracePattern(pattern, options) {
  return expand(pattern, options);
}

/**
 * Return the default maximum expansion limit constant.
 * @returns {number} Default expansion maximum (100000)
 */
function getExpansionLimit() {
  return EXPANSION_MAX;
}

module.exports = {
  expand,
  EXPANSION_MAX,
  expandBracePattern,
  getExpansionLimit,
};

import assert from 'node:assert';
import { createRequire } from 'node:module';

const require = createRequire(import.meta.url);
const {
  expand,
  EXPANSION_MAX,
  expandBracePattern,
  getExpansionLimit,
} = require('../src/index.js');

// 1. Export contract checks
assert.strictEqual(typeof expand, 'function', 'expand should be a function');
assert.strictEqual(typeof EXPANSION_MAX, 'number', 'EXPANSION_MAX should be a number');
assert.strictEqual(EXPANSION_MAX, 100000, 'EXPANSION_MAX should equal 100000');
assert.strictEqual(typeof expandBracePattern, 'function', 'expandBracePattern should be a function');
assert.strictEqual(typeof getExpansionLimit, 'function', 'getExpansionLimit should be a function');
assert.strictEqual(getExpansionLimit(), 100000, 'getExpansionLimit should return 100000');

// 2. Empty string returns empty array
assert.deepStrictEqual(expand(''), [], 'expand("") should return []');
assert.deepStrictEqual(expandBracePattern(''), [], 'expandBracePattern("") should return []');

// 3. Comma-separated list expansion
assert.deepStrictEqual(
  expand('file.{js,ts,mjs}'),
  ['file.js', 'file.ts', 'file.mjs'],
  'expand should expand comma-separated lists'
);
assert.deepStrictEqual(
  expandBracePattern('image.{png,jpeg,webp}'),
  ['image.png', 'image.jpeg', 'image.webp'],
  'expandBracePattern should expand comma-separated lists'
);

// 4. Numeric range expansion (forward, backward, step, padding)
assert.deepStrictEqual(
  expand('{1..4}'),
  ['1', '2', '3', '4'],
  'expand should expand ascending numeric range'
);
assert.deepStrictEqual(
  expand('{4..1}'),
  ['4', '3', '2', '1'],
  'expand should expand descending numeric range'
);
assert.deepStrictEqual(
  expand('{0..6..2}'),
  ['0', '2', '4', '6'],
  'expand should expand numeric range with step'
);
assert.deepStrictEqual(
  expand('{01..03}'),
  ['01', '02', '03'],
  'expand should preserve zero-padding in numeric range'
);

// 5. Alphabetic range expansion (forward, backward, step)
assert.deepStrictEqual(
  expand('{a..c}'),
  ['a', 'b', 'c'],
  'expand should expand ascending alphabetic range'
);
assert.deepStrictEqual(
  expand('{c..a}'),
  ['c', 'b', 'a'],
  'expand should expand descending alphabetic range'
);
assert.deepStrictEqual(
  expand('{a..e..2}'),
  ['a', 'c', 'e'],
  'expand should expand alphabetic range with step'
);

// 6. Nested braces and Cartesian products
assert.deepStrictEqual(
  expand('a{b,c{d,e}}f'),
  ['abf', 'acdf', 'acef'],
  'expand should support nested braces'
);
assert.deepStrictEqual(
  expand('{a,b}{1,2}'),
  ['a1', 'a2', 'b1', 'b2'],
  'expand should compute Cartesian products of multiple brace groups'
);

// 7. Escaping and max options limit
assert.deepStrictEqual(
  expand('a\\{b,c\\}d'),
  ['a{b,c}d'],
  'expand should handle escaped brace characters'
);
assert.deepStrictEqual(
  expand('{1..10}', { max: 3 }),
  ['1', '2', '3'],
  'expand should limit output items when max option is provided'
);

console.log('All contract tests passed.');