yargs-parser 21.1.1: yargs-parser

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 yargs-parser in pkg:npm/yargs-parser@21.1.1
Kind: HOW

Use EXACTLY these public packages and versions:
  - pkg:npm/yargs-parser@21.1.1
Demonstrate these symbols/APIs:
  - yargs-parser

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:sha256:07c0bb20553fa2bf9b442f4edc48d0aeaa37e002bef2d1ef377acdd30b70fb1e","contract":["yargsParser parses positional arguments and flags into argv object with _ and key-value pairs","yargsParser coerces types with boolean and string option configurations","yargsParser parses arrays and respects array option configurations","yargsParser supports option aliases mapping multiple flags to the same parsed value","yargsParser supports default option values when arguments are omitted","yargsParser expands kebab-case flags to camelCase properties by default","yargsParser detailed returns parsed argv along with configuration aliases and error fields"],"goal":"verify yargs-parser in pkg:npm/yargs-parser@21.1.1","kind":"HOW","packages":["pkg:npm/yargs-parser@21.1.1"],"schemaVersion":1,"symbols":["yargs-parser"]},"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/yargs-parser@21.1.1"],"schemaVersion":1,"subject":"pkg:npm/yargs-parser@21.1.1","symbols":["yargs-parser"],"verifierAdapter":"node-typescript@1"}

{
  "name": "yargs-parser-sample",
  "version": "1.0.0",
  "lockfileVersion": 3,
  "requires": true,
  "packages": {
    "": {
      "name": "yargs-parser-sample",
      "version": "1.0.0",
      "dependencies": {
        "yargs-parser": "21.1.1"
      }
    },
    "node_modules/yargs-parser": {
      "version": "21.1.1",
      "resolved": "https://registry.npmjs.org/yargs-parser/-/yargs-parser-21.1.1.tgz",
      "integrity": "sha512-tVpsJW7DdjecAiFpbIB1e3qxIQsE6NoPc5/eTdrbbIC4h0LVsWhnoa3g+m2HclBIujHzsxZ4VJVA+GUuc2/LBw==",
      "license": "ISC",
      "engines": {
        "node": ">=12"
      }
    }
  }
}

{
  "name": "yargs-parser-sample",
  "version": "1.0.0",
  "private": true,
  "description": "Clean-room verification for yargs-parser",
  "dependencies": {
    "yargs-parser": "21.1.1"
  }
}

{
  "schemaVersion": 1,
  "goal": "verify yargs-parser in pkg:npm/yargs-parser@21.1.1",
  "kind": "HOW",
  "packages": [
    "pkg:npm/yargs-parser@21.1.1"
  ],
  "symbols": [
    "yargs-parser"
  ]
}

import assert from 'node:assert';
import parser from 'yargs-parser';

// 1. yargsParser parses positional arguments and flags into argv object with _ and key-value pairs
const res1 = parser(['hello', '--name', 'world', 'extra']);
assert.deepStrictEqual(res1._, ['hello', 'extra']);
assert.strictEqual(res1.name, 'world');

// 2. yargsParser coerces types with boolean and string option configurations
const res2 = parser(['--verbose', '--code', '0123'], {
  boolean: ['verbose'],
  string: ['code']
});
assert.strictEqual(res2.verbose, true);
assert.strictEqual(res2.code, '0123');

// 3. yargsParser parses arrays and respects array option configurations
const res3 = parser(['--items', 'a', '--items', 'b'], {
  array: ['items']
});
assert.deepStrictEqual(res3.items, ['a', 'b']);

// 4. yargsParser supports option aliases mapping multiple flags to the same parsed value
const res4 = parser(['-f', 'file.txt'], {
  alias: { f: ['file'] }
});
assert.strictEqual(res4.f, 'file.txt');
assert.strictEqual(res4.file, 'file.txt');

// 5. yargsParser supports default option values when arguments are omitted
const res5 = parser([], {
  default: { port: 8080 }
});
assert.strictEqual(res5.port, 8080);

// 6. yargsParser expands kebab-case flags to camelCase properties by default
const res6 = parser(['--user-name', 'alice']);
assert.strictEqual(res6['user-name'], 'alice');
assert.strictEqual(res6.userName, 'alice');

// 7. yargsParser detailed returns parsed argv along with configuration aliases and error fields
const res7 = parser.detailed(['--flag']);
assert.strictEqual(res7.argv.flag, true);
assert.strictEqual(res7.error, null);
assert(typeof res7.configuration === 'object');
assert(typeof res7.aliases === 'object');

console.log('Contract passed');