cookie 1.1.1: parse

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 cookie.parse in pkg:npm/cookie@1.1.1
Kind: HOW

Use EXACTLY these public packages and versions:
  - pkg:npm/cookie@1.1.1
Demonstrate these symbols/APIs:
  - cookie.parse

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:sha256:7793bf74f3f433cf60a8c89255d713904c0e946342f867f5ae4e2f7add0c3bba","contract":["cookie.parse parses simple key-value cookie pairs separated by semicolons","cookie.parse trims leading and trailing whitespace around names and values","cookie.parse decodes URL-encoded values by default","cookie.parse retains original string when percent-decoding fails","cookie.parse assigns only the first value when duplicate cookie names appear","cookie.parse supports custom decode function option to transform values","cookie.parse handles empty values and empty or short header strings gracefully"],"goal":"verify cookie.parse in pkg:npm/cookie@1.1.1","kind":"HOW","packages":["pkg:npm/cookie@1.1.1"],"schemaVersion":1,"symbols":["cookie.parse"]},"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/cookie@1.1.1"],"schemaVersion":1,"subject":"pkg:npm/cookie@1.1.1","symbols":["cookie.parse"],"verifierAdapter":"node-typescript@1"}

{
  "name": "sample-cookie-parse",
  "version": "1.0.0",
  "lockfileVersion": 3,
  "requires": true,
  "packages": {
    "": {
      "name": "sample-cookie-parse",
      "version": "1.0.0",
      "license": "MIT-0",
      "dependencies": {
        "cookie": "1.1.1"
      }
    },
    "node_modules/cookie": {
      "version": "1.1.1",
      "resolved": "https://registry.npmjs.org/cookie/-/cookie-1.1.1.tgz",
      "integrity": "sha512-ei8Aos7ja0weRpFzJnEA9UHJ/7XQmqglbRwnf2ATjcB9Wq874VKH9kfjjirM6UhU2/E5fFYadylyhFldcqSidQ==",
      "license": "MIT",
      "engines": {
        "node": ">=18"
      },
      "funding": {
        "type": "opencollective",
        "url": "https://opencollective.com/express"
      }
    }
  }
}

{
  "name": "sample-cookie-parse",
  "version": "1.0.0",
  "type": "module",
  "private": true,
  "license": "MIT-0",
  "scripts": {
    "test": "node test/contract.mjs"
  },
  "dependencies": {
    "cookie": "1.1.1"
  }
}

{
  "schemaVersion": 1,
  "goal": "verify cookie.parse in pkg:npm/cookie@1.1.1",
  "kind": "HOW",
  "packages": [
    "pkg:npm/cookie@1.1.1"
  ],
  "symbols": [
    "cookie.parse"
  ]
}

import * as cookie from 'cookie';

const { parse } = cookie;

/**
 * Parse a Cookie header string into an object of key-value pairs.
 * @param {string} str Cookie header string
 * @param {import('cookie').ParseOptions} [options] Parse options
 * @returns {Record<string, string | undefined>} Parsed cookies object
 */
export function parseCookieHeader(str, options) {
  return parse(str, options);
}

export { cookie, parse };
export default parse;

import assert from 'node:assert/strict';
import { cookie, parse, parseCookieHeader } from '../src/index.mjs';

// 1. cookie.parse parses simple key-value cookie pairs separated by semicolons
{
  const result = parse('foo=bar; equation=E%3Dmc%5E2');
  assert.equal(result.foo, 'bar');
  assert.equal(result.equation, 'E=mc^2');

  const helperResult = parseCookieHeader('user=guest; session=active');
  assert.equal(helperResult.user, 'guest');
  assert.equal(helperResult.session, 'active');
}

// 2. cookie.parse trims leading and trailing whitespace around names and values
{
  const result = cookie.parse('  theme =  dark  ;   lang = en-US  ');
  assert.equal(result.theme, 'dark');
  assert.equal(result.lang, 'en-US');
}

// 3. cookie.parse decodes URL-encoded values by default
{
  const result = parse('token=abc%20123%2Fxyz; special=%24%26%2B');
  assert.equal(result.token, 'abc 123/xyz');
  assert.equal(result.special, '$&+');
}

// 4. cookie.parse retains original string when percent-decoding fails
{
  // Malformed percent-encoded sequences fallback to raw string
  const result = parse('bad=%E0%A4%A; regular=valid');
  assert.equal(result.bad, '%E0%A4%A');
  assert.equal(result.regular, 'valid');
}

// 5. cookie.parse assigns only the first value when duplicate cookie names appear
{
  const result = parse('color=blue; color=red; color=green');
  assert.equal(result.color, 'blue');
}

// 6. cookie.parse supports custom decode function option to transform values
{
  const result = parse('env=PROD; flag=TRUE', {
    decode: (val) => val.toLowerCase()
  });
  assert.equal(result.env, 'prod');
  assert.equal(result.flag, 'true');
}

// 7. cookie.parse handles empty values and empty or short header strings gracefully
{
  const emptyValues = parse('a=; b=; c=foo');
  assert.equal(emptyValues.a, '');
  assert.equal(emptyValues.b, '');
  assert.equal(emptyValues.c, 'foo');

  const emptyString = parse('');
  assert.deepEqual(Object.keys(emptyString), []);

  const singleChar = parse('x');
  assert.deepEqual(Object.keys(singleChar), []);
}

console.log('Contract assertions passed.');