has-flag 4.0.0: hasFlag

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 hasFlag in pkg:npm/has-flag@4.0.0
Kind: HOW

Use EXACTLY these public packages and versions:
  - pkg:npm/has-flag@4.0.0
Demonstrate these symbols/APIs:
  - hasFlag
Constraints:
  - executionContext: node
Required runtime conditions:
  - ecosystem: npm
  - language: javascript
  - moduleSystem: cjs
  - packageManager: npm@10.9.8
  - runtime: node@22.23.2

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:b58e5c8f01e7b00ef14732877a75342161b9ffe1a9a7d20de05808cadd625e85","constraints":{"executionContext":"node"},"contract":["assert hasFlag detects long flag specified without leading dashes in custom argv","assert hasFlag detects long flag specified with leading dashes in custom argv","assert hasFlag detects single-character short flag specified without leading dash in custom argv","assert hasFlag detects single-character short flag specified with leading dash in custom argv","assert hasFlag returns false when target flag is missing from custom argv","assert hasFlag ignores target flag when positioned after double dash terminator","assert hasFlag detects target flag when positioned before double dash terminator","assert hasFlag evaluates process.argv when argv parameter is omitted"],"goal":"verify hasFlag in pkg:npm/has-flag@4.0.0","kind":"HOW","packages":["pkg:npm/has-flag@4.0.0"],"schemaVersion":1,"symbols":["hasFlag"]},"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/has-flag@4.0.0"],"schemaVersion":1,"subject":"pkg:npm/has-flag@4.0.0","symbols":["hasFlag"],"verifierAdapter":"node-typescript@1"}

const hasFlag = require('has-flag');

function checkFlag(flag, customArgv) {
  return hasFlag(flag, customArgv);
}

function checkDefaultArgv(flag) {
  return hasFlag(flag);
}

module.exports = {
  hasFlag,
  checkFlag,
  checkDefaultArgv,
};

{
  "name": "sample-has-flag",
  "version": "1.0.0",
  "lockfileVersion": 3,
  "requires": true,
  "packages": {
    "": {
      "name": "sample-has-flag",
      "version": "1.0.0",
      "license": "MIT-0",
      "dependencies": {
        "has-flag": "4.0.0"
      }
    },
    "node_modules/has-flag": {
      "version": "4.0.0",
      "resolved": "https://registry.npmjs.org/has-flag/-/has-flag-4.0.0.tgz",
      "integrity": "sha512-EykJT/Q1KjTWctppgIAgfSO0tKVuZUjhgMr17kqTumMl6Afv3EISleU7qZUzoXDFTAHTDC4NOoG/ZxU3EvlMPQ==",
      "license": "MIT",
      "engines": {
        "node": ">=8"
      }
    }
  }
}

{
  "name": "sample-has-flag",
  "version": "1.0.0",
  "description": "Minimal clean-room sample verifying hasFlag in has-flag",
  "main": "index.js",
  "license": "MIT-0",
  "dependencies": {
    "has-flag": "4.0.0"
  }
}

{
  "schemaVersion": 1,
  "goal": "verify hasFlag in pkg:npm/has-flag@4.0.0",
  "kind": "HOW",
  "packages": [
    "pkg:npm/has-flag@4.0.0"
  ],
  "symbols": [
    "hasFlag"
  ],
  "constraints": {
    "executionContext": "node"
  },
  "runtimeConditions": {
    "ecosystem": "npm",
    "language": "javascript",
    "moduleSystem": "cjs",
    "packageManager": "npm@10.9.8",
    "runtime": "node@22.23.2"
  }
}

import assert from 'node:assert';
import hasFlag from 'has-flag';
import { checkFlag, checkDefaultArgv } from '../index.js';

// 1. Detect long flag without leading dashes
assert.strictEqual(
  checkFlag('unicorn', ['--unicorn']),
  true,
  'hasFlag should detect long flag without prefix'
);

// 2. Detect long flag with leading dashes
assert.strictEqual(
  checkFlag('--unicorn', ['--unicorn']),
  true,
  'hasFlag should detect long flag with leading dashes'
);

// 3. Detect single-character short flag without leading dash
assert.strictEqual(
  checkFlag('u', ['-u']),
  true,
  'hasFlag should detect single-character flag without prefix'
);

// 4. Detect single-character short flag with leading dash
assert.strictEqual(
  checkFlag('-u', ['-u']),
  true,
  'hasFlag should detect single-character flag with leading dash'
);

// 5. Return false when flag is not present in argv
assert.strictEqual(
  checkFlag('unicorn', ['--foo', '--bar']),
  false,
  'hasFlag should return false when flag is missing'
);

// 6. Ignore flag positioned after terminator --
assert.strictEqual(
  checkFlag('unicorn', ['--foo', '--', '--unicorn']),
  false,
  'hasFlag should ignore flags after -- terminator'
);

// 7. Detect flag positioned before terminator --
assert.strictEqual(
  checkFlag('unicorn', ['--unicorn', '--', '--foo']),
  true,
  'hasFlag should detect flag before -- terminator'
);

// 8. Default to process.argv when argv is omitted
const originalArgv = process.argv;
try {
  process.argv = ['node', 'app.js', '--custom-flag'];
  assert.strictEqual(
    checkDefaultArgv('custom-flag'),
    true,
    'hasFlag should check process.argv when argv argument is omitted'
  );
  assert.strictEqual(
    checkDefaultArgv('nonexistent-flag'),
    false,
    'hasFlag should return false for absent flag in process.argv'
  );
} finally {
  process.argv = originalArgv;
}

console.log('All hasFlag contract assertions passed.');