@exodus/bytes 1.15.1: toHex, fromHex, toBase64

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/%40exodus/bytes@1.15.1
Kind: HOW

Use EXACTLY these public packages and versions:
  - pkg:npm/%40exodus/bytes@1.15.1

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:sha256:3814c61ee2cb86b95dc8d2016122a492aed061405cc3d276ed9e5e35aaf16b34","contract":["toHex encodes Uint8Array into a lowercase hex string","fromHex decodes a hex string to Uint8Array and supports format options","fromHex throws SyntaxError on invalid hex input","toBase64 encodes Uint8Array to RFC 4648 standard base64 with padding","fromBase64 decodes RFC 4648 standard base64 string to Uint8Array","toBase64url encodes Uint8Array to URL-safe base64 without padding","fromBase64url decodes URL-safe base64 string to Uint8Array","fromBase64any auto-detects and decodes both standard and URL-safe base64 strings","toBase58 encodes Uint8Array to Bitcoin base58 string and fromBase58 decodes it","toBase58xrp encodes Uint8Array using XRP alphabet and fromBase58xrp decodes it","fromBase58 throws SyntaxError on invalid base58 character","utf8fromString strictly encodes string to Uint8Array and throws TypeError on invalid Unicode","utf8toString strictly decodes Uint8Array to string and throws TypeError on invalid UTF-8 bytes","utf8fromStringLoose and utf8toStringLoose handle invalid Unicode using replacement character"],"goal":"verify pkg:npm/%40exodus/bytes@1.15.1","kind":"HOW","packages":["pkg:npm/%40exodus/bytes@1.15.1"],"schemaVersion":1,"symbols":["toHex","fromHex","toBase64","fromBase64","toBase64url","fromBase64url","fromBase64any","toBase58","fromBase58","toBase58xrp","fromBase58xrp","utf8fromString","utf8toString","utf8fromStringLoose","utf8toStringLoose"]},"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/%40exodus/bytes@1.15.1"],"schemaVersion":1,"subject":"pkg:npm/%40exodus/bytes@1.15.1","symbols":["toHex","fromHex","toBase64","fromBase64","toBase64url","fromBase64url","fromBase64any","toBase58","fromBase58","toBase58xrp","fromBase58xrp","utf8fromString","utf8toString","utf8fromStringLoose","utf8toStringLoose"],"verifierAdapter":"node-typescript@1"}

{
  "name": "sample-exodus-bytes",
  "version": "1.0.0",
  "lockfileVersion": 3,
  "requires": true,
  "packages": {
    "": {
      "name": "sample-exodus-bytes",
      "version": "1.0.0",
      "license": "MIT-0",
      "dependencies": {
        "@exodus/bytes": "1.15.1"
      }
    },
    "node_modules/@exodus/bytes": {
      "version": "1.15.1",
      "resolved": "https://registry.npmjs.org/@exodus/bytes/-/bytes-1.15.1.tgz",
      "integrity": "sha512-S6mL0yNB/Abt9Ei4tq8gDhcczc4S3+vQ4ra7vxnAf+YHC02srtqxKKZghx2Dq6p0e66THKwR6r8N6P95wEty7Q==",
      "license": "MIT",
      "engines": {
        "node": "^20.19.0 || ^22.12.0 || >=24.0.0"
      },
      "peerDependencies": {
        "@noble/hashes": "^1.8.0 || ^2.0.0"
      },
      "peerDependenciesMeta": {
        "@noble/hashes": {
          "optional": true
        }
      }
    }
  }
}

{
  "name": "sample-exodus-bytes",
  "version": "1.0.0",
  "private": true,
  "description": "Clean-room verification of @exodus/bytes",
  "main": "src/index.js",
  "license": "MIT-0",
  "dependencies": {
    "@exodus/bytes": "1.15.1"
  }
}

{
  "schemaVersion": 1,
  "goal": "verify pkg:npm/%40exodus/bytes@1.15.1",
  "kind": "HOW",
  "packages": [
    "pkg:npm/%40exodus/bytes@1.15.1"
  ]
}

'use strict';

const { toHex, fromHex } = require('@exodus/bytes/hex.js');
const {
  toBase64,
  fromBase64,
  toBase64url,
  fromBase64url,
  fromBase64any
} = require('@exodus/bytes/base64.js');
const {
  toBase58,
  fromBase58,
  toBase58xrp,
  fromBase58xrp
} = require('@exodus/bytes/base58.js');
const {
  utf8fromString,
  utf8toString,
  utf8fromStringLoose,
  utf8toStringLoose
} = require('@exodus/bytes/utf8.js');

module.exports = {
  toHex,
  fromHex,
  toBase64,
  fromBase64,
  toBase64url,
  fromBase64url,
  fromBase64any,
  toBase58,
  fromBase58,
  toBase58xrp,
  fromBase58xrp,
  utf8fromString,
  utf8toString,
  utf8fromStringLoose,
  utf8toStringLoose
};

import assert from 'node:assert/strict';
import { createRequire } from 'node:module';

const require = createRequire(import.meta.url);
const {
  toHex,
  fromHex,
  toBase64,
  fromBase64,
  toBase64url,
  fromBase64url,
  fromBase64any,
  toBase58,
  fromBase58,
  toBase58xrp,
  fromBase58xrp,
  utf8fromString,
  utf8toString,
  utf8fromStringLoose,
  utf8toStringLoose
} = require('../src/index.js');

// 1. Export verification
assert.equal(typeof toHex, 'function', 'toHex must be a function');
assert.equal(typeof fromHex, 'function', 'fromHex must be a function');
assert.equal(typeof toBase64, 'function', 'toBase64 must be a function');
assert.equal(typeof fromBase64, 'function', 'fromBase64 must be a function');
assert.equal(typeof toBase64url, 'function', 'toBase64url must be a function');
assert.equal(typeof fromBase64url, 'function', 'fromBase64url must be a function');
assert.equal(typeof fromBase64any, 'function', 'fromBase64any must be a function');
assert.equal(typeof toBase58, 'function', 'toBase58 must be a function');
assert.equal(typeof fromBase58, 'function', 'fromBase58 must be a function');
assert.equal(typeof toBase58xrp, 'function', 'toBase58xrp must be a function');
assert.equal(typeof fromBase58xrp, 'function', 'fromBase58xrp must be a function');
assert.equal(typeof utf8fromString, 'function', 'utf8fromString must be a function');
assert.equal(typeof utf8toString, 'function', 'utf8toString must be a function');
assert.equal(typeof utf8fromStringLoose, 'function', 'utf8fromStringLoose must be a function');
assert.equal(typeof utf8toStringLoose, 'function', 'utf8toStringLoose must be a function');

// 2. toHex encodes Uint8Array into a lowercase hex string
{
  const data = new Uint8Array([0xde, 0xad, 0xbe, 0xef]);
  assert.equal(toHex(data), 'deadbeef');
}

// 3. fromHex decodes a hex string to Uint8Array and supports format options
{
  const expected = new Uint8Array([0xca, 0xfe, 0xba, 0xbe]);
  const decoded = fromHex('cafebabe');
  assert.deepEqual(decoded, expected);
  const bufferDecoded = fromHex('cafebabe', 'buffer');
  assert(Buffer.isBuffer(bufferDecoded));
  assert.deepEqual(bufferDecoded, Buffer.from([0xca, 0xfe, 0xba, 0xbe]));
}

// 4. fromHex throws SyntaxError on invalid hex input
{
  assert.throws(() => fromHex('not_hex_zz'), SyntaxError);
}

// 5. toBase64 encodes Uint8Array to RFC 4648 standard base64 with padding
{
  const data = new Uint8Array([104, 101, 108, 108, 111]);
  assert.equal(toBase64(data), 'aGVsbG8=');
}

// 6. fromBase64 decodes RFC 4648 standard base64 string to Uint8Array
{
  const expected = new Uint8Array([104, 101, 108, 108, 111]);
  assert.deepEqual(fromBase64('aGVsbG8='), expected);
}

// 7. toBase64url encodes Uint8Array to URL-safe base64 without padding
{
  const data = new Uint8Array([104, 101, 108, 108, 111]);
  assert.equal(toBase64url(data), 'aGVsbG8');
}

// 8. fromBase64url decodes URL-safe base64 string to Uint8Array
{
  const expected = new Uint8Array([104, 101, 108, 108, 111]);
  assert.deepEqual(fromBase64url('aGVsbG8'), expected);
}

// 9. fromBase64any auto-detects and decodes both standard and URL-safe base64 strings
{
  const expected = new Uint8Array([104, 101, 108, 108, 111]);
  assert.deepEqual(fromBase64any('aGVsbG8='), expected);
  assert.deepEqual(fromBase64any('aGVsbG8'), expected);
}

// 10. toBase58 encodes Uint8Array to Bitcoin base58 string and fromBase58 decodes it
{
  const data = new Uint8Array([104, 101, 108, 108, 111]);
  const encoded = toBase58(data);
  assert.equal(encoded, 'Cn8eVZg');
  assert.deepEqual(fromBase58(encoded), data);
}

// 11. toBase58xrp encodes Uint8Array using XRP alphabet and fromBase58xrp decodes it
{
  const data = new Uint8Array([104, 101, 108, 108, 111]);
  const encoded = toBase58xrp(data);
  assert.deepEqual(fromBase58xrp(encoded), data);
}

// 12. fromBase58 throws SyntaxError on invalid base58 character
{
  assert.throws(() => fromBase58('invalid_0OI_'), SyntaxError);
}

// 13. utf8fromString strictly encodes string to Uint8Array and throws TypeError on invalid Unicode
{
  const str = 'CodeSampleX';
  const encoded = utf8fromString(str);
  assert.deepEqual(encoded, new Uint8Array([67, 111, 100, 101, 83, 97, 109, 112, 108, 101, 88]));
  assert.throws(() => utf8fromString('\uD800'), TypeError);
}

// 14. utf8toString strictly decodes Uint8Array to string and throws TypeError on invalid UTF-8 bytes
{
  const bytes = new Uint8Array([67, 111, 100, 101, 83, 97, 109, 112, 108, 101, 88]);
  assert.equal(utf8toString(bytes), 'CodeSampleX');
  assert.throws(() => utf8toString(new Uint8Array([0x80, 0x81])), TypeError);
}

// 15. utf8fromStringLoose and utf8toStringLoose handle invalid Unicode using replacement character
{
  assert.deepEqual(utf8fromStringLoose('\uD800'), new Uint8Array([0xef, 0xbf, 0xbd]));
  assert.equal(utf8toStringLoose(new Uint8Array([0x80])), '\uFFFD');
}

console.log('All @exodus/bytes contract assertions passed successfully.');