pvutils 1.2.0: getParametersValue

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 pvutils.getParametersValue in pkg:npm/pvutils@1.2.0
Kind: HOW

Use EXACTLY these public packages and versions:
  - pkg:npm/pvutils@1.2.0
Demonstrate these symbols/APIs:
  - pvutils.getParametersValue

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:sha256:0ff4d8679ef95644dc415e16fffe0f92a5c7dfe377538a47585919e35d0e488c","contract":["getParametersValue returns property value when the key exists and is non-null","getParametersValue returns defaultValue when parameters is not an Object","getParametersValue returns defaultValue when key is missing or explicitly undefined","getParametersValue returns defaultValue when property value is null","getParametersValue preserves falsy non-nullish values such as false, 0, and empty string","getParametersValue retrieves nested objects, arrays, and functions by reference"],"goal":"verify pvutils.getParametersValue in pkg:npm/pvutils@1.2.0","kind":"HOW","packages":["pkg:npm/pvutils@1.2.0"],"schemaVersion":1,"symbols":["pvutils.getParametersValue"]},"contractCommand":["node","test/contract.js"],"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/pvutils@1.2.0"],"schemaVersion":1,"subject":"pkg:npm/pvutils@1.2.0","symbols":["pvutils.getParametersValue"],"verifierAdapter":"node-typescript@1"}

{
  "name": "sample-pvutils",
  "version": "1.0.0",
  "lockfileVersion": 3,
  "requires": true,
  "packages": {
    "": {
      "name": "sample-pvutils",
      "version": "1.0.0",
      "license": "MIT-0",
      "dependencies": {
        "pvutils": "1.2.0"
      }
    },
    "node_modules/pvutils": {
      "version": "1.2.0",
      "resolved": "https://registry.npmjs.org/pvutils/-/pvutils-1.2.0.tgz",
      "integrity": "sha512-BbubeCEyTuQjVMakvJQ/Sxbc93F2pwmbsxONT/ZRrwU7Ua38d8unYTwXpTVLAKJ4BDuH9IGztCjQcd/N/39Dvg==",
      "license": "MIT",
      "engines": {
        "node": ">=16.0.0"
      }
    }
  }
}

{
  "name": "sample-pvutils",
  "version": "1.0.0",
  "private": true,
  "description": "Clean-room verification sample for pvutils.getParametersValue",
  "main": "src/index.js",
  "scripts": {
    "test": "node test/contract.js"
  },
  "dependencies": {
    "pvutils": "1.2.0"
  },
  "license": "MIT-0"
}

{
  "schemaVersion": 1,
  "goal": "verify pvutils.getParametersValue in pkg:npm/pvutils@1.2.0",
  "kind": "HOW",
  "packages": [
    "pkg:npm/pvutils@1.2.0"
  ],
  "symbols": [
    "pvutils.getParametersValue"
  ]
}

const pvutils = require('pvutils');

/**
 * Retrieves a property value from a parameter object or falls back to defaultValue.
 * @param {Record<string, any>} parameters - Object containing parameters.
 * @param {string} name - Parameter name to retrieve.
 * @param {any} defaultValue - Default fallback value if parameter is missing, null, or undefined.
 * @returns {any} Resolved parameter value or defaultValue.
 */
function getParameter(parameters, name, defaultValue) {
  return pvutils.getParametersValue(parameters, name, defaultValue);
}

module.exports = {
  pvutils,
  getParameter
};

const assert = require('node:assert');
const pvutils = require('pvutils');
const { getParameter } = require('../src/index.js');

// 1. getParametersValue returns property value when the key exists and is non-null
const options = { timeout: 5000, mode: 'strict' };
assert.strictEqual(pvutils.getParametersValue(options, 'timeout', 1000), 5000);
assert.strictEqual(getParameter(options, 'timeout', 1000), 5000);
assert.strictEqual(pvutils.getParametersValue(options, 'mode', 'default'), 'strict');
assert.strictEqual(getParameter(options, 'mode', 'default'), 'strict');

// 2. getParametersValue returns defaultValue when parameters is not an Object
assert.strictEqual(pvutils.getParametersValue(null, 'key', 'fallback'), 'fallback');
assert.strictEqual(getParameter(null, 'key', 'fallback'), 'fallback');
assert.strictEqual(pvutils.getParametersValue(undefined, 'key', 'fallback'), 'fallback');
assert.strictEqual(getParameter(undefined, 'key', 'fallback'), 'fallback');
assert.strictEqual(pvutils.getParametersValue(42, 'key', 'fallback'), 'fallback');
assert.strictEqual(getParameter(42, 'key', 'fallback'), 'fallback');
assert.strictEqual(pvutils.getParametersValue('primitive', 'key', 'fallback'), 'fallback');
assert.strictEqual(getParameter('primitive', 'key', 'fallback'), 'fallback');
assert.strictEqual(pvutils.getParametersValue(true, 'key', 'fallback'), 'fallback');
assert.strictEqual(getParameter(true, 'key', 'fallback'), 'fallback');

// 3. getParametersValue returns defaultValue when key is missing or explicitly undefined
const emptyParams = {};
assert.strictEqual(pvutils.getParametersValue(emptyParams, 'missing', 'fallback'), 'fallback');
assert.strictEqual(getParameter(emptyParams, 'missing', 'fallback'), 'fallback');
const undefParams = { key: undefined };
assert.strictEqual(pvutils.getParametersValue(undefParams, 'key', 'fallback'), 'fallback');
assert.strictEqual(getParameter(undefParams, 'key', 'fallback'), 'fallback');

// 4. getParametersValue returns defaultValue when property value is null
const nullParams = { nullableKey: null };
assert.strictEqual(pvutils.getParametersValue(nullParams, 'nullableKey', 'fallback'), 'fallback');
assert.strictEqual(getParameter(nullParams, 'nullableKey', 'fallback'), 'fallback');

// 5. getParametersValue preserves falsy non-nullish values such as false, 0, and empty string
const falsyParams = {
  flag: false,
  count: 0,
  text: '',
  notANumber: NaN
};
assert.strictEqual(pvutils.getParametersValue(falsyParams, 'flag', true), false);
assert.strictEqual(getParameter(falsyParams, 'flag', true), false);
assert.strictEqual(pvutils.getParametersValue(falsyParams, 'count', 10), 0);
assert.strictEqual(getParameter(falsyParams, 'count', 10), 0);
assert.strictEqual(pvutils.getParametersValue(falsyParams, 'text', 'placeholder'), '');
assert.strictEqual(getParameter(falsyParams, 'text', 'placeholder'), '');
assert.strictEqual(Number.isNaN(pvutils.getParametersValue(falsyParams, 'notANumber', 0)), true);
assert.strictEqual(Number.isNaN(getParameter(falsyParams, 'notANumber', 0)), true);

// 6. getParametersValue retrieves nested objects, arrays, and functions by reference
const nestedConfig = { level: 2 };
const itemsList = ['a', 'b', 'c'];
const handlerFn = () => 'ok';
const complexParams = {
  config: nestedConfig,
  items: itemsList,
  handler: handlerFn
};
assert.strictEqual(pvutils.getParametersValue(complexParams, 'config', {}), nestedConfig);
assert.strictEqual(getParameter(complexParams, 'config', {}), nestedConfig);
assert.strictEqual(pvutils.getParametersValue(complexParams, 'items', []), itemsList);
assert.strictEqual(getParameter(complexParams, 'items', []), itemsList);
assert.strictEqual(pvutils.getParametersValue(complexParams, 'handler', null), handlerFn);
assert.strictEqual(getParameter(complexParams, 'handler', null), handlerFn);

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