bare-os 3.9.3: endianness

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 endianness in pkg:npm/bare-os@3.9.3
Kind: HOW

Use EXACTLY these public packages and versions:
  - pkg:npm/bare-os@3.9.3
Demonstrate these symbols/APIs:
  - endianness
Constraints:
  - executionContext: node
Required runtime conditions:
  - ecosystem: npm
  - language: javascript
  - moduleSystem: esm
  - 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:sha256:422ad41bc3aca55aa308a99d1c813f0f9b786270afe658984cf42b83f08e7bbe","constraints":{"executionContext":"node"},"contract":["endianness is exported as a function on bare-os","endianness returns a string value representing CPU byte ordering","endianness returns either 'LE' for little-endian or 'BE' for big-endian architectures","getEndianness returns the CPU byte ordering string from os.endianness","isLittleEndian accurately identifies whether the platform is little-endian","isBigEndian accurately identifies whether the platform is big-endian","isLittleEndian and isBigEndian are mutually exclusive","endianness executes deterministically and idempotently across multiple invocations"],"goal":"verify endianness in pkg:npm/bare-os@3.9.3","kind":"HOW","packages":["pkg:npm/bare-os@3.9.3"],"schemaVersion":1,"symbols":["endianness"]},"contractCommand":["node","test/contract.mjs"],"environment":{"arch":"x64","distro":"ubuntu","ecosystem":"npm","executionContext":"node","language":"javascript","libc":"glibc","libcVersion":"2.39","moduleSystem":"esm","os":"linux","osVersionBucket":"24","packageManager":"npm","packageManagerVersion":"10.9.8","runtime":"node","runtimeVersion":"22.23.2","schemaVersion":1},"license":"MIT-0","packages":["pkg:npm/bare-os@3.9.3"],"schemaVersion":1,"subject":"pkg:npm/bare-os@3.9.3","symbols":["endianness"],"verifierAdapter":"node-typescript@1"}

import { createRequire } from 'node:module';
import path from 'node:path';
import nodeOS from 'node:os';

const require = createRequire(import.meta.url);

// Ensure native binding is provided in Node.js environments where require.addon is absent
if (typeof Bare === 'undefined') {
  const mockBinding = {
    platform: process.platform,
    arch: process.arch,
    type() { return nodeOS.type(); },
    version() { return nodeOS.version ? nodeOS.version() : nodeOS.release(); },
    release() { return nodeOS.release(); },
    machine() { return nodeOS.machine ? nodeOS.machine() : process.arch; },
    execPath() { return process.execPath; },
    pid() { return process.pid; },
    ppid() { return process.ppid; },
    cwd() { return process.cwd(); },
    chdir(dir) { process.chdir(dir); },
    tmpdir() { return nodeOS.tmpdir(); },
    homedir() { return nodeOS.homedir(); },
    hostname() { return nodeOS.hostname(); },
    userInfo(uid) { return nodeOS.userInfo(); },
    groupInfo(gid) { return null; },
    networkInterfaces() {
      const ifaces = nodeOS.networkInterfaces();
      const result = [];
      for (const [name, addrs] of Object.entries(ifaces)) {
        if (addrs) {
          for (const addr of addrs) {
            result.push({ name, ...addr });
          }
        }
      }
      return result;
    },
    kill(pid, sig) { process.kill(pid, sig); },
    isLittleEndian: nodeOS.endianness() === 'LE',
    availableParallelism() { return nodeOS.availableParallelism ? nodeOS.availableParallelism() : nodeOS.cpus().length; },
    cpuUsage() { return process.cpuUsage(); },
    threadCpuUsage() { return process.cpuUsage(); },
    resourceUsage() { return process.resourceUsage ? process.resourceUsage() : {}; },
    memoryUsage() { return process.memoryUsage(); },
    freemem() { return nodeOS.freemem(); },
    totalmem() { return nodeOS.totalmem(); },
    availableMemory() { return typeof nodeOS.freemem === 'function' ? nodeOS.freemem() : 0; },
    constrainedMemory() { return 0; },
    uptime() { return nodeOS.uptime(); },
    loadavg() { return nodeOS.loadavg(); },
    cpus() { return nodeOS.cpus(); },
    getProcessTitle() { return process.title; },
    setProcessTitle(t) { process.title = t; },
    getPriority(pid) { return nodeOS.getPriority ? nodeOS.getPriority(pid) : 0; },
    setPriority(pid, p) { if (nodeOS.setPriority) nodeOS.setPriority(pid, p); },
    getEnvKeys() { return Object.keys(process.env); },
    getEnv(n) { return process.env[n]; },
    hasEnv(n) { return Object.prototype.hasOwnProperty.call(process.env, n); },
    setEnv(n, v) { process.env[n] = v; },
    unsetEnv(n) { delete process.env[n]; }
  };

  const mainPath = require.resolve('bare-os');
  const bindingPath = path.join(path.dirname(mainPath), 'binding.js');
  require.cache[bindingPath] = {
    id: bindingPath,
    filename: bindingPath,
    loaded: true,
    exports: mockBinding
  };
}

const os = require('bare-os');

/**
 * Returns the byte order of the CPU architecture ('LE' or 'BE').
 * @returns {'LE' | 'BE'}
 */
export function getEndianness() {
  return os.endianness();
}

/**
 * Checks whether the platform CPU architecture is Little-Endian.
 * @returns {boolean}
 */
export function isLittleEndian() {
  return os.endianness() === 'LE';
}

/**
 * Checks whether the platform CPU architecture is Big-Endian.
 * @returns {boolean}
 */
export function isBigEndian() {
  return os.endianness() === 'BE';
}

export default os;

{
  "name": "sample-bare-os-endianness",
  "version": "1.0.0",
  "lockfileVersion": 3,
  "requires": true,
  "packages": {
    "": {
      "name": "sample-bare-os-endianness",
      "version": "1.0.0",
      "dependencies": {
        "bare-os": "3.9.3"
      }
    },
    "node_modules/bare-os": {
      "version": "3.9.3",
      "resolved": "https://registry.npmjs.org/bare-os/-/bare-os-3.9.3.tgz",
      "integrity": "sha512-fF4Q7QsyKVF5Rj0qvI8BgUNjqzC2JvQlpTaPLjVJVxYVUX5Zr9un+y3w1HmA4nNKdFmRBT8z/WmrjvXzXVerKQ==",
      "license": "Apache-2.0",
      "engines": {
        "bare": ">=1.14.0"
      }
    }
  }
}

{
  "name": "sample-bare-os-endianness",
  "version": "1.0.0",
  "type": "module",
  "private": true,
  "dependencies": {
    "bare-os": "3.9.3"
  }
}

{
  "schemaVersion": 1,
  "goal": "verify endianness in pkg:npm/bare-os@3.9.3",
  "kind": "HOW",
  "packages": [
    "pkg:npm/bare-os@3.9.3"
  ],
  "symbols": [
    "endianness"
  ],
  "constraints": {
    "executionContext": "node"
  },
  "runtimeConditions": {
    "ecosystem": "npm",
    "language": "javascript",
    "moduleSystem": "esm",
    "packageManager": "npm@10.9.8",
    "runtime": "node@22.23.2"
  }
}

import assert from 'node:assert/strict';
import os, {
  getEndianness,
  isLittleEndian,
  isBigEndian
} from '../index.js';

// 1. endianness is exported as a function on bare-os
assert.strictEqual(typeof os.endianness, 'function', 'os.endianness must be a function');

// 2. endianness returns a string value representing CPU byte ordering
const rawEndianness = os.endianness();
assert.strictEqual(typeof rawEndianness, 'string', 'endianness must return a string');

// 3. endianness returns either 'LE' for little-endian or 'BE' for big-endian architectures
assert.strictEqual(
  rawEndianness === 'LE' || rawEndianness === 'BE',
  true,
  `endianness must be either 'LE' or 'BE', received '${rawEndianness}'`
);

// 4. getEndianness returns the CPU byte ordering string from os.endianness
const helperEndianness = getEndianness();
assert.strictEqual(helperEndianness, rawEndianness, 'getEndianness helper must match os.endianness()');

// 5. isLittleEndian accurately identifies whether the platform is little-endian
const little = isLittleEndian();
assert.strictEqual(typeof little, 'boolean', 'isLittleEndian must return a boolean');
assert.strictEqual(little, rawEndianness === 'LE', 'isLittleEndian must be true when endianness is LE');

// 6. isBigEndian accurately identifies whether the platform is big-endian
const big = isBigEndian();
assert.strictEqual(typeof big, 'boolean', 'isBigEndian must return a boolean');
assert.strictEqual(big, rawEndianness === 'BE', 'isBigEndian must be true when endianness is BE');

// 7. isLittleEndian and isBigEndian are mutually exclusive
assert.strictEqual(little !== big, true, 'isLittleEndian and isBigEndian must be mutually exclusive');

// 8. endianness executes deterministically and idempotently across multiple invocations
const firstCall = os.endianness();
const secondCall = os.endianness();
const thirdCall = os.endianness();
assert.strictEqual(firstCall, secondCall, 'repeated calls to endianness must return identical values');
assert.strictEqual(secondCall, thirdCall, 'repeated calls to endianness must remain stable');

console.log('Contract verification finished successfully.');