bare-os 3.9.3: getPriority

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 getPriority 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:
  - getPriority

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:a7dab1f77c843208ddccb14c9f56d2602e0aa011a86ce2e22b39710231620ce4","contract":["package manifest exports getPriority function signature in TypeScript definitions and requires Bare engine \u003e=1.14.0","getPriority validates that pid argument is an integer and throws TypeError for non-integer types","getPriority defaults pid to 0 for current process when called without arguments","getPriority accepts explicit integer process identifiers","native C binding registers bare_os_get_priority mapping to libuv uv_os_getpriority","constants module exports priority map with standard process scheduling priority levels"],"goal":"verify getPriority in pkg:npm/bare-os@3.9.3","kind":"HOW","packages":["pkg:npm/bare-os@3.9.3"],"schemaVersion":1,"symbols":["getPriority"]},"contractCommand":["node","test/contract.mjs"],"environment":{"arch":"x64","distro":"ubuntu","ecosystem":"npm","libc":"glibc","libcVersion":"2.39","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":["getPriority"],"verifierAdapter":"node-typescript@1"}

{
  "name": "bare-os-sample",
  "version": "1.0.0",
  "lockfileVersion": 3,
  "requires": true,
  "packages": {
    "": {
      "name": "bare-os-sample",
      "version": "1.0.0",
      "license": "MIT-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": "bare-os-sample",
  "version": "1.0.0",
  "private": true,
  "type": "module",
  "license": "MIT-0",
  "dependencies": {
    "bare-os": "3.9.3"
  }
}

{
  "schemaVersion": 1,
  "goal": "verify getPriority in pkg:npm/bare-os@3.9.3",
  "kind": "HOW",
  "packages": [
    "pkg:npm/bare-os@3.9.3"
  ],
  "symbols": [
    "getPriority"
  ]
}

import fs from 'node:fs';
import path from 'node:path';
import { createRequire } from 'node:module';

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

/**
 * Validates a process ID according to bare-os validation requirements.
 *
 * @param {unknown} [pid=0] - The process ID to validate.
 * @returns {number} The validated integer PID.
 * @throws {TypeError} If pid is not an integer.
 */
export function validateProcessId(pid = 0) {
  if (!Number.isInteger(pid)) {
    throw new TypeError(`Process ID must be an integer. Received type ${typeof pid} (${pid})`);
  }
  return pid;
}

/**
 * Standard scheduling priority constants corresponding to bare-os priority map.
 */
export const PRIORITY_LEVELS = Object.freeze({
  PRIORITY_LOW: 19,
  PRIORITY_BELOW_NORMAL: 10,
  PRIORITY_NORMAL: 0,
  PRIORITY_ABOVE_NORMAL: -10,
  PRIORITY_HIGH: -19,
  PRIORITY_HIGHEST: -20,
});

/**
 * Inspects bare-os package metadata.
 *
 * @returns {object} The parsed package.json manifest.
 */
export function getBareOsMetadata() {
  const pkgPath = require.resolve('bare-os/package');
  return JSON.parse(fs.readFileSync(pkgPath, 'utf8'));
}

import assert from 'node:assert/strict';
import { createRequire } from 'node:module';
import fs from 'node:fs';
import path from 'node:path';
import { validateProcessId, PRIORITY_LEVELS, getBareOsMetadata } from '../src/index.mjs';

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

// 1. Resolve bare-os package manifest and verify exports and metadata
const pkgPath = require.resolve('bare-os/package');
const pkg = JSON.parse(fs.readFileSync(pkgPath, 'utf8'));

assert.equal(pkg.name, 'bare-os', 'Package name must be bare-os');
assert.equal(pkg.version, '3.9.3', 'Package version must be 3.9.3');
assert.equal(pkg.license, 'Apache-2.0', 'Package license must be Apache-2.0');
assert.equal(pkg.addon, true, 'Package must be marked as addon');
assert.equal(pkg.engines?.bare, '>=1.14.0', 'Package must specify Bare engine requirement');

assert.ok(pkg.exports, 'Package must define exports map');
assert.equal(pkg.exports['.'].types, './index.d.ts', 'Root export must specify index.d.ts types');
assert.equal(pkg.exports['.'].default, './index.js', 'Root export must specify index.js default');
assert.equal(pkg.exports['./constants'].types, './lib/constants.d.ts', 'Constants export must specify types');
assert.equal(pkg.exports['./constants'].default, './lib/constants.js', 'Constants export must specify default');

const pkgDir = path.dirname(pkgPath);

// 2. Verify TypeScript type definitions for getPriority and priority constants
const indexDts = fs.readFileSync(path.join(pkgDir, 'index.d.ts'), 'utf8');
assert.ok(
  indexDts.includes('export function getPriority(pid?: number): number'),
  'index.d.ts must declare export function getPriority(pid?: number): number'
);
assert.ok(
  indexDts.includes('export function setPriority(priority: number): void'),
  'index.d.ts must declare export function setPriority'
);

const constantsDts = fs.readFileSync(path.join(pkgDir, 'lib', 'constants.d.ts'), 'utf8');
assert.ok(
  constantsDts.includes('priority: Record<string, number>'),
  'lib/constants.d.ts must declare priority: Record<string, number>'
);

// 3. Verify getPriority JavaScript wrapper and parameter validation
const bindingPath = path.join(pkgDir, 'binding.js');
let capturedPid = null;
require.cache[bindingPath] = {
  id: bindingPath,
  filename: bindingPath,
  loaded: true,
  exports: {
    getPriority: (pid) => {
      capturedPid = pid;
      return 0;
    },
    setPriority: () => {},
    signals: {},
    errnos: {},
    priority: PRIORITY_LEVELS,
  },
};

const bareOs = require('bare-os');
assert.equal(typeof bareOs.getPriority, 'function', 'bare-os must export getPriority function');

// Test default PID behaviour (pid defaults to 0)
capturedPid = null;
const defaultPriority = bareOs.getPriority();
assert.equal(capturedPid, 0, 'getPriority() must default pid to 0');
assert.equal(defaultPriority, 0, 'getPriority() must return priority from binding');

// Test explicit PID passing
capturedPid = null;
const pidPriority = bareOs.getPriority(1024);
assert.equal(capturedPid, 1024, 'getPriority(1024) must pass pid 1024 to binding');
assert.equal(pidPriority, 0, 'getPriority(1024) must return priority from binding');

// Test parameter type validation (must throw TypeError for non-integers)
const invalidPids = ['0', '123', 3.14, NaN, Infinity, -Infinity, null, {}, [], false, true];
for (const invalidPid of invalidPids) {
  assert.throws(
    () => bareOs.getPriority(invalidPid),
    {
      name: 'TypeError',
      message: /Process ID must be an integer/,
    },
    `getPriority(${JSON.stringify(invalidPid)}) must throw TypeError for non-integer pid`
  );
}

// 4. Verify C native binding implementation for getPriority
const bindingC = fs.readFileSync(path.join(pkgDir, 'binding.c'), 'utf8');
assert.ok(
  bindingC.includes('V("getPriority", bare_os_get_priority)'),
  'binding.c must register bare_os_get_priority function under getPriority export'
);
assert.ok(
  bindingC.includes('bare_os_get_priority(js_env_t *env, js_callback_info_t *info)'),
  'binding.c must define bare_os_get_priority function'
);
assert.ok(
  bindingC.includes('uv_os_getpriority(pid, &priority)'),
  'bare_os_get_priority must call uv_os_getpriority'
);

// 5. Verify sample helper functions
assert.equal(validateProcessId(0), 0);
assert.equal(validateProcessId(555), 555);
assert.throws(() => validateProcessId('abc'), TypeError);

const meta = getBareOsMetadata();
assert.equal(meta.name, 'bare-os');
assert.equal(meta.version, '3.9.3');

console.log('All bare-os getPriority contract tests passed successfully.');