brace-expansion 2.1.4

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/brace-expansion@2.1.4
Kind: HOW

Use EXACTLY these public packages and versions:
  - pkg:npm/brace-expansion@2.1.4

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:sha256:70bd8d08e308c8ef344b71fba39753a47845ea90c673c88b7ca8577aaa46a821","contract":["expand expands comma-separated alternatives within curly braces into string combinations","expand expands numeric and alphabetic sequences with optional step increments","expand expands nested brace patterns and computes Cartesian products for adjacent brace groups","expand handles numeric sequences with zero-padding and reverse ordering","expand returns an empty array for empty input and preserves literal text when no braces are matched","expand supports max and maxLength options to bound output results"],"goal":"verify pkg:npm/brace-expansion@2.1.4","kind":"HOW","packages":["pkg:npm/brace-expansion@2.1.4"],"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/brace-expansion@2.1.4"],"schemaVersion":1,"subject":"pkg:npm/brace-expansion@2.1.4","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": {
        "brace-expansion": "2.1.4"
      }
    },
    "node_modules/balanced-match": {
      "version": "1.0.2",
      "resolved": "https://registry.npmjs.org/balanced-match/-/balanced-match-1.0.2.tgz",
      "integrity": "sha512-3oSeUO0TMV67hN1AmbXsK4yaqU7tjiHlbxRDZOpH0KW9+CeX4bRAaX0Anxt0tx2MrpRpWwQaPwIlISEJhYU5Pw==",
      "license": "MIT"
    },
    "node_modules/brace-expansion": {
      "version": "2.1.4",
      "resolved": "https://registry.npmjs.org/brace-expansion/-/brace-expansion-2.1.4.tgz",
      "integrity": "sha512-hGfVzPxthbf3+2yjg/RBs60cB0FhqBS/zvdV/4wn4/BmN0bNMMHPc4V/BbFieqf1TKAGGAHnY4eSjajCl0f2Xg==",
      "license": "MIT",
      "dependencies": {
        "balanced-match": "^1.0.0"
      }
    }
  }
}

{
  "name": "sample-brace-expansion",
  "version": "1.0.0",
  "private": true,
  "description": "Clean-room verification sample for brace-expansion",
  "main": "src/index.js",
  "scripts": {
    "test": "node test/contract.js"
  },
  "dependencies": {
    "brace-expansion": "2.1.4"
  },
  "license": "MIT-0"
}

{
  "schemaVersion": 1,
  "goal": "verify pkg:npm/brace-expansion@2.1.4",
  "kind": "HOW",
  "packages": [
    "pkg:npm/brace-expansion@2.1.4"
  ]
}

const expand = require('brace-expansion');

function expandPattern(pattern, options) {
  return expand(pattern, options);
}

module.exports = {
  expandPattern,
  expand
};

const assert = require('node:assert/strict');
const expand = require('brace-expansion');
const { expandPattern } = require('../src/index.js');

// 1. Comma-separated alternatives within curly braces
assert.deepStrictEqual(expand('file.{js,ts}'), ['file.js', 'file.ts'], 'should expand comma alternatives');
assert.deepStrictEqual(expand('http://example.com/{foo,bar}'), ['http://example.com/foo', 'http://example.com/bar'], 'should expand URLs');
assert.deepStrictEqual(expandPattern('item-{a,b,c}'), ['item-a', 'item-b', 'item-c'], 'wrapper should expand comma alternatives');

// 2. Numeric and alphabetic sequences with optional step increments
assert.deepStrictEqual(expand('{1..3}'), ['1', '2', '3'], 'should expand ascending numeric sequence');
assert.deepStrictEqual(expand('{a..c}'), ['a', 'b', 'c'], 'should expand ascending alphabetic sequence');
assert.deepStrictEqual(expand('{1..5..2}'), ['1', '3', '5'], 'should expand numeric sequence with step increment');
assert.deepStrictEqual(expand('{a..e..2}'), ['a', 'c', 'e'], 'should expand alphabetic sequence with step increment');

// 3. Nested brace expressions and Cartesian products
assert.deepStrictEqual(expand('a{b,c{d,e}}f'), ['abf', 'acdf', 'acef'], 'should resolve nested brace expressions');
assert.deepStrictEqual(expand('{a,b}{1,2}'), ['a1', 'a2', 'b1', 'b2'], 'should compute Cartesian products of adjacent groups');

// 4. Zero-padding and reverse ordering
assert.deepStrictEqual(expand('{01..03}'), ['01', '02', '03'], 'should preserve zero-padding in numeric sequence');
assert.deepStrictEqual(expand('{3..1}'), ['3', '2', '1'], 'should expand descending numeric sequence');
assert.deepStrictEqual(expand('{c..a}'), ['c', 'b', 'a'], 'should expand descending alphabetic sequence');

// 5. Empty input and literal text without braces
assert.deepStrictEqual(expand(''), [], 'should return empty array for empty string');
assert.deepStrictEqual(expand('plain-text'), ['plain-text'], 'should preserve literal text without braces');

// 6. Max and maxLength options
assert.deepStrictEqual(expand('{1..10}', { max: 3 }), ['1', '2', '3'], 'should respect max expansion option');
assert.deepStrictEqual(expand('{a,b,c}', { maxLength: 2 }), ['a', 'b'], 'should respect maxLength option');

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