std-env 4.2.0: isLinux

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 std-env.isLinux in pkg:npm/std-env@4.2.0
Kind: HOW

Use EXACTLY these public packages and versions:
  - pkg:npm/std-env@4.2.0
Demonstrate these symbols/APIs:
  - std-env.isLinux

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:sha256:04c256d107fad16074e2b923235ea43cd754bf09f8936d330d03d6b1076947dc","contract":["isLinux is exported as a boolean indicating if the current platform is Linux","isLinux evaluates to true on Linux platforms where process.platform is linux","isLinux is consistent with platform and mutually exclusive with isWindows and isMacOS"],"goal":"verify std-env.isLinux in pkg:npm/std-env@4.2.0","kind":"HOW","packages":["pkg:npm/std-env@4.2.0"],"schemaVersion":1,"symbols":["std-env.isLinux"]},"contractCommand":["node","test/contract.mjs"],"environment":{"arch":"x64","distro":"ubuntu","ecosystem":"npm","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/std-env@4.2.0"],"schemaVersion":1,"subject":"pkg:npm/std-env@4.2.0","symbols":["std-env.isLinux"],"verifierAdapter":"node-typescript@1"}

{
  "name": "sample-std-env-is-linux",
  "version": "1.0.0",
  "lockfileVersion": 3,
  "requires": true,
  "packages": {
    "": {
      "name": "sample-std-env-is-linux",
      "version": "1.0.0",
      "license": "MIT-0",
      "dependencies": {
        "std-env": "4.2.0"
      }
    },
    "node_modules/std-env": {
      "version": "4.2.0",
      "resolved": "https://registry.npmjs.org/std-env/-/std-env-4.2.0.tgz",
      "integrity": "sha512-oCUKSupKTHX53EyjDtuZQ64pjLJ6yYCtpmEw0goYxtjG9KpbRe8KAsl2tBUGU9DyMcJ0RwJ8GqJAFzMXcXW1Rw==",
      "license": "MIT"
    }
  }
}

{
  "name": "sample-std-env-is-linux",
  "version": "1.0.0",
  "type": "module",
  "private": true,
  "description": "Clean-room verification sample for std-env isLinux",
  "main": "src/index.mjs",
  "scripts": {
    "test": "node test/contract.mjs"
  },
  "dependencies": {
    "std-env": "4.2.0"
  },
  "license": "MIT-0"
}

{
  "schemaVersion": 1,
  "goal": "verify std-env.isLinux in pkg:npm/std-env@4.2.0",
  "kind": "HOW",
  "packages": [
    "pkg:npm/std-env@4.2.0"
  ],
  "symbols": [
    "std-env.isLinux"
  ]
}

import { isLinux, platform, isWindows, isMacOS } from 'std-env';

/**
 * Returns true if the runtime environment is Linux.
 * @returns {boolean}
 */
export function checkIsLinux() {
  return isLinux;
}

export { isLinux, platform, isWindows, isMacOS };

import assert from 'node:assert/strict';
import { isLinux, platform, isWindows, isMacOS, checkIsLinux } from '../src/index.mjs';

// 1. isLinux is exported as a boolean indicating if the current platform is Linux
{
  assert.equal(typeof isLinux, 'boolean');
  assert.equal(typeof checkIsLinux(), 'boolean');
}

// 2. isLinux evaluates to true on Linux platforms where process.platform is linux
{
  assert.equal(process.platform, 'linux');
  assert.equal(isLinux, true);
  assert.equal(checkIsLinux(), true);
}

// 3. isLinux is consistent with platform and mutually exclusive with isWindows and isMacOS
{
  assert.equal(platform, 'linux');
  assert.equal(isLinux, /^linux/i.test(platform));
  assert.equal(isWindows, false);
  assert.equal(isMacOS, false);
}

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