pvutils 1.2.0: stringToArrayBuffer

audit=false
fund=false

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.stringToArrayBuffer 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.stringToArrayBuffer
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:dfe761965b1d975f64ea78f19af74435ebe0095fc0bd4308747ad69c06213503","constraints":{"executionContext":"node"},"contract":["assert pvutils.stringToArrayBuffer converts an ASCII string into an ArrayBuffer with matching byte length","assert pvutils.stringToArrayBuffer correctly maps string character codes to Uint8Array byte values","assert pvutils.stringToArrayBuffer handles empty string input by returning an empty ArrayBuffer of zero byte length","assert pvutils.stringToArrayBuffer accurately preserves binary byte string values across the full 0 to 255 range","assert pvutils.stringToArrayBuffer output can be reconstructed back to the original string using arrayBufferToString"],"goal":"verify pvutils.stringToArrayBuffer in pkg:npm/pvutils@1.2.0","kind":"HOW","packages":["pkg:npm/pvutils@1.2.0"],"schemaVersion":1,"symbols":["pvutils.stringToArrayBuffer"]},"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/pvutils@1.2.0"],"schemaVersion":1,"subject":"pkg:npm/pvutils@1.2.0","symbols":["pvutils.stringToArrayBuffer"],"verifierAdapter":"node-typescript@1"}

const pvutils = require('pvutils');

function convertStringToBuffer(str) {
  return pvutils.stringToArrayBuffer(str);
}

function convertBufferToString(buffer) {
  return pvutils.arrayBufferToString(buffer);
}

function convertStringToUint8Array(str) {
  const buf = pvutils.stringToArrayBuffer(str);
  return new Uint8Array(buf);
}

function roundTripConversion(str) {
  const buf = pvutils.stringToArrayBuffer(str);
  return pvutils.arrayBufferToString(buf);
}

module.exports = {
  pvutils,
  convertStringToBuffer,
  convertBufferToString,
  convertStringToUint8Array,
  roundTripConversion,
};

{
  "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",
  "description": "Minimal clean-room sample verifying pvutils.stringToArrayBuffer in pvutils",
  "main": "index.js",
  "license": "MIT-0",
  "dependencies": {
    "pvutils": "1.2.0"
  }
}

{
  "schemaVersion": 1,
  "goal": "verify pvutils.stringToArrayBuffer in pkg:npm/pvutils@1.2.0",
  "kind": "HOW",
  "packages": [
    "pkg:npm/pvutils@1.2.0"
  ],
  "symbols": [
    "pvutils.stringToArrayBuffer"
  ],
  "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 pvutils from 'pvutils';
import {
  convertStringToBuffer,
  convertBufferToString,
  convertStringToUint8Array,
  roundTripConversion,
} from '../index.js';

// 1. pvutils.stringToArrayBuffer converts an ASCII string into an ArrayBuffer with matching byte length
const asciiStr = 'Hello, CodeSampleX!';
const asciiBuf = convertStringToBuffer(asciiStr);
assert(asciiBuf instanceof ArrayBuffer, 'stringToArrayBuffer must return an ArrayBuffer instance');
assert.strictEqual(asciiBuf.byteLength, asciiStr.length, 'ArrayBuffer byteLength must match string length');

// 2. pvutils.stringToArrayBuffer correctly maps string character codes to Uint8Array byte values
const testStr = 'CodeSampleX-123';
const u8View = convertStringToUint8Array(testStr);
assert.strictEqual(u8View.length, testStr.length, 'Uint8Array length must match string length');
for (let i = 0; i < testStr.length; i++) {
  assert.strictEqual(
    u8View[i],
    testStr.charCodeAt(i),
    `Byte at index ${i} must match character code of '${testStr[i]}'`
  );
}

// 3. pvutils.stringToArrayBuffer handles empty string input by returning an empty ArrayBuffer of zero byte length
const emptyBuf = convertStringToBuffer('');
assert(emptyBuf instanceof ArrayBuffer, 'Empty string conversion must return an ArrayBuffer instance');
assert.strictEqual(emptyBuf.byteLength, 0, 'Empty string ArrayBuffer must have byteLength 0');

// 4. pvutils.stringToArrayBuffer accurately preserves binary byte string values across the full 0 to 255 range
const byteValues = [];
for (let b = 0; b <= 255; b++) {
  byteValues.push(b);
}
const binaryStr = String.fromCharCode(...byteValues);
const binaryBuf = convertStringToBuffer(binaryStr);
assert.strictEqual(binaryBuf.byteLength, 256, 'Binary string buffer must have 256 bytes');
const binaryU8 = new Uint8Array(binaryBuf);
for (let b = 0; b <= 255; b++) {
  assert.strictEqual(binaryU8[b], b, `Byte value at offset ${b} must match original value`);
}

// 5. pvutils.stringToArrayBuffer output can be reconstructed back to the original string using arrayBufferToString
const origText = 'Round-trip verification for pvutils string and ArrayBuffer conversion';
const reconstructed = roundTripConversion(origText);
assert.strictEqual(
  reconstructed,
  origText,
  'Reconstructed string via arrayBufferToString must exactly match original string'
);

console.log('All pvutils.stringToArrayBuffer contract assertions passed.');