png-to-ico 2.1.8

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 pkg:npm/png-to-ico@2.1.8
Kind: HOW

Use EXACTLY these public packages and versions:
  - pkg:npm/png-to-ico@2.1.8

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:sha256:18bf6d5517fb784fb95588c3e9545178576d6241ffb11fa862d18b1a52bc725b","contract":["pngToIco converts a PNG buffer into a Windows ICO format buffer with valid headers","pngToIco converts a PNG image file path into a Windows ICO format buffer","pngToIco converts an array of PNG images into a multi-resolution Windows ICO buffer","pngToIco rejects with an error when given invalid image data or a non-existent file path"],"goal":"verify pkg:npm/png-to-ico@2.1.8","kind":"HOW","packages":["pkg:npm/png-to-ico@2.1.8"],"schemaVersion":1},"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/png-to-ico@2.1.8"],"schemaVersion":1,"subject":"pkg:npm/png-to-ico@2.1.8","verifierAdapter":"node-typescript@1"}

{
  "name": "verify-png-to-ico",
  "version": "1.0.0",
  "lockfileVersion": 3,
  "requires": true,
  "packages": {
    "": {
      "name": "verify-png-to-ico",
      "version": "1.0.0",
      "dependencies": {
        "png-to-ico": "2.1.8"
      }
    },
    "node_modules/@types/node": {
      "version": "17.0.45",
      "resolved": "https://registry.npmjs.org/@types/node/-/node-17.0.45.tgz",
      "integrity": "sha512-w+tIMs3rq2afQdsPJlODhoUEKzFP1ayaoyl1CcnwtIlsVe7K7bA1NGm4s3PraqTLlXnbIN84zuBlxBWo1u9BLw==",
      "license": "MIT"
    },
    "node_modules/minimist": {
      "version": "1.2.8",
      "resolved": "https://registry.npmjs.org/minimist/-/minimist-1.2.8.tgz",
      "integrity": "sha512-2yyAR8qBkN3YuheJanUpWC5U3bb5osDywNB8RzDVlDwDHbocAJveqqj1u8+SVD7jkWT4yvsHCpWqqWqAxb0zCA==",
      "license": "MIT",
      "funding": {
        "url": "https://github.com/sponsors/ljharb"
      }
    },
    "node_modules/png-to-ico": {
      "version": "2.1.8",
      "resolved": "https://registry.npmjs.org/png-to-ico/-/png-to-ico-2.1.8.tgz",
      "integrity": "sha512-Nf+IIn/cZ/DIZVdGveJp86NG5uNib1ZXMiDd/8x32HCTeKSvgpyg6D/6tUBn1QO/zybzoMK0/mc3QRgAyXdv9w==",
      "license": "MIT",
      "dependencies": {
        "@types/node": "^17.0.36",
        "minimist": "^1.2.6",
        "pngjs": "^6.0.0"
      },
      "bin": {
        "png-to-ico": "bin/cli.js"
      },
      "engines": {
        "node": ">=8"
      }
    },
    "node_modules/pngjs": {
      "version": "6.0.0",
      "resolved": "https://registry.npmjs.org/pngjs/-/pngjs-6.0.0.tgz",
      "integrity": "sha512-TRzzuFRRmEoSW/p1KVAmiOgPco2Irlah+bGFCeNfJXxxYGwSw7YwAOAcd7X28K/m5bjBWKsC29KyoMfHbypayg==",
      "license": "MIT",
      "engines": {
        "node": ">=12.13.0"
      }
    }
  }
}

{
  "name": "verify-png-to-ico",
  "version": "1.0.0",
  "type": "module",
  "dependencies": {
    "png-to-ico": "2.1.8"
  }
}

{
  "schemaVersion": 1,
  "goal": "verify pkg:npm/png-to-ico@2.1.8",
  "kind": "HOW",
  "packages": [
    "pkg:npm/png-to-ico@2.1.8"
  ]
}

import pngToIco from 'png-to-ico';

export async function convertPngToIco(input) {
  return await pngToIco(input);
}

export default pngToIco;

import assert from 'node:assert';
import fs from 'node:fs';
import path from 'node:path';
import { fileURLToPath } from 'node:url';
import pngToIco, { convertPngToIco } from '../src/index.mjs';

const __filename = fileURLToPath(import.meta.url);
const __dirname = path.dirname(__filename);

// 16x16 PNG and 32x32 PNG fixtures encoded as base64
const PNG_16X16_BASE64 = 'iVBORw0KGgoAAAANSUhEUgAAABAAAAAQCAYAAAAf8/9hAAAALklEQVR4AaXBAQEAMAiAMCTZo725hmCb/W8JJJJIIokkkkgiiSSSSCKJJJJIogNi2gLene9JPAAAAABJRU5ErkJggg==';
const PNG_32X32_BASE64 = 'iVBORw0KGgoAAAANSUhEUgAAACAAAAAgCAYAAABzenr0AAAARklEQVR4AcXBAQEAMAiAMCTZo725xmCb/W8JSUxiEpOYxCQmMYlJTGISk5jEJCYxiUlMYhKTmMQkJjGJSUxiEpOYxCQmsQNH1wL+DE99BwAAAABJRU5ErkJggg==';

const png1 = Buffer.from(PNG_16X16_BASE64, 'base64');
const png2 = Buffer.from(PNG_32X32_BASE64, 'base64');


const fixtureDir = path.join(__dirname, 'fixtures');
const file1 = path.join(fixtureDir, 'icon1.png');
const file2 = path.join(fixtureDir, 'icon2.png');

if (!fs.existsSync(fixtureDir)) {
  fs.mkdirSync(fixtureDir, { recursive: true });
}
fs.writeFileSync(file1, png1);
fs.writeFileSync(file2, png2);

try {
  // 1. Convert PNG buffer into Windows ICO format buffer
  const icoFromBuffer = await convertPngToIco(png1);
  assert.ok(Buffer.isBuffer(icoFromBuffer), 'Output must be a Buffer');
  assert.strictEqual(icoFromBuffer.readUInt16LE(0), 0, 'ICO header reserved must be 0');
  assert.strictEqual(icoFromBuffer.readUInt16LE(2), 1, 'ICO header type must be 1 (icon)');
  assert.ok(icoFromBuffer.readUInt16LE(4) >= 1, 'ICO image count must be at least 1');

  // 2. Convert PNG image file path into Windows ICO format buffer
  const icoFromFile = await pngToIco(file1);
  assert.ok(Buffer.isBuffer(icoFromFile), 'Output must be a Buffer');
  assert.strictEqual(icoFromFile.readUInt16LE(0), 0, 'ICO header reserved must be 0');
  assert.strictEqual(icoFromFile.readUInt16LE(2), 1, 'ICO header type must be 1 (icon)');
  assert.ok(icoFromFile.readUInt16LE(4) >= 1, 'ICO image count must be at least 1');

  // 3. Convert an array of PNG images into a multi-resolution Windows ICO buffer
  const icoFromArray = await pngToIco([file1, file2]);
  assert.ok(Buffer.isBuffer(icoFromArray), 'Output must be a Buffer');
  assert.strictEqual(icoFromArray.readUInt16LE(0), 0, 'ICO header reserved must be 0');
  assert.strictEqual(icoFromArray.readUInt16LE(2), 1, 'ICO header type must be 1 (icon)');
  assert.strictEqual(icoFromArray.readUInt16LE(4), 2, 'ICO image count must be 2 for 2 input files');

  // 4. Rejection when given invalid image data or a non-existent file path
  await assert.rejects(
    async () => {
      await pngToIco(Buffer.from('corrupted-image-data-not-a-png'));
    },
    (err) => {
      assert.ok(err instanceof Error, 'Expected rejection with Error on invalid buffer');
      return true;
    }
  );

  await assert.rejects(
    async () => {
      await pngToIco(path.join(fixtureDir, 'non-existent-image.png'));
    },
    (err) => {
      assert.ok(err instanceof Error, 'Expected rejection with Error on non-existent file');
      return true;
    }
  );

  console.log('Contract tests passed successfully.');
} finally {
  if (fs.existsSync(file1)) fs.unlinkSync(file1);
  if (fs.existsSync(file2)) fs.unlinkSync(file2);
  if (fs.existsSync(fixtureDir)) fs.rmdirSync(fixtureDir);
}