proper-lockfile 4.1.2: unlockSync

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 proper-lockfile.unlockSync in pkg:npm/proper-lockfile@4.1.2
Kind: HOW

Use EXACTLY these public packages and versions:
  - pkg:npm/proper-lockfile@4.1.2
Demonstrate these symbols/APIs:
  - proper-lockfile.unlockSync

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:badb0be0fbb00a8040280b35761ff27471025dad9a7934cdabbc03e70c473ebe","contract":["proper-lockfile.unlockSync synchronously releases a lock acquired with lockSync","proper-lockfile.unlockSync synchronously releases a lock acquired with lock","proper-lockfile.unlockSync throws ENOTACQUIRED when called on a file not locked by the caller","proper-lockfile.unlockSync releases a lock with custom lockfilePath synchronously"],"goal":"verify proper-lockfile.unlockSync in pkg:npm/proper-lockfile@4.1.2","kind":"HOW","packages":["pkg:npm/proper-lockfile@4.1.2"],"schemaVersion":1,"symbols":["proper-lockfile.unlockSync"]},"contractCommand":["node","test/contract.cjs"],"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/proper-lockfile@4.1.2"],"schemaVersion":1,"subject":"pkg:npm/proper-lockfile@4.1.2","symbols":["proper-lockfile.unlockSync"],"verifierAdapter":"node-typescript@1"}

'use strict';

const lockfile = require('proper-lockfile');

/**
 * Synchronously releases a lock on a file.
 * @param {string} file
 * @param {object} [options]
 */
function releaseLockSync(file, options) {
  return lockfile.unlockSync(file, options);
}

module.exports = {
  releaseLockSync,
  lockfile
};

{
  "name": "sample-proper-lockfile-unlocksync",
  "version": "1.0.0",
  "lockfileVersion": 3,
  "requires": true,
  "packages": {
    "": {
      "name": "sample-proper-lockfile-unlocksync",
      "version": "1.0.0",
      "license": "MIT-0",
      "dependencies": {
        "proper-lockfile": "4.1.2"
      }
    },
    "node_modules/graceful-fs": {
      "version": "4.2.11",
      "resolved": "https://registry.npmjs.org/graceful-fs/-/graceful-fs-4.2.11.tgz",
      "integrity": "sha512-RbJ5/jmFcNNCcDV5o9eTnBLJ/HszWV0P73bc+Ff4nS/rJj+YaS6IGyiOL0VoBYX+l1Wrl3k63h/KrH+nhJ0XvQ==",
      "license": "ISC"
    },
    "node_modules/proper-lockfile": {
      "version": "4.1.2",
      "resolved": "https://registry.npmjs.org/proper-lockfile/-/proper-lockfile-4.1.2.tgz",
      "integrity": "sha512-TjNPblN4BwAWMXU8s9AEz4JmQxnD1NNL7bNOY/AKUzyamc379FWASUhc/K1pL2noVb+XmZKLL68cjzLsiOAMaA==",
      "license": "MIT",
      "dependencies": {
        "graceful-fs": "^4.2.4",
        "retry": "^0.12.0",
        "signal-exit": "^3.0.2"
      }
    },
    "node_modules/retry": {
      "version": "0.12.0",
      "resolved": "https://registry.npmjs.org/retry/-/retry-0.12.0.tgz",
      "integrity": "sha512-9LkiTwjUh6rT555DtE9rTX+BKByPfrMzEAtnlEtdEwr3Nkffwiihqe2bWADg+OQRjt9gl6ICdmB/ZFDCGAtSow==",
      "license": "MIT",
      "engines": {
        "node": ">= 4"
      }
    },
    "node_modules/signal-exit": {
      "version": "3.0.7",
      "resolved": "https://registry.npmjs.org/signal-exit/-/signal-exit-3.0.7.tgz",
      "integrity": "sha512-wnD2ZE+l+SPC/uoS0vXeE9L1+0wuaMqKlfz9AMUo38JsyLSBWSFcHR1Rri62LZc12vLr1gb3jl7iwQhgwpAbGQ==",
      "license": "ISC"
    }
  }
}

{
  "name": "sample-proper-lockfile-unlocksync",
  "version": "1.0.0",
  "private": true,
  "description": "verify proper-lockfile.unlockSync in pkg:npm/proper-lockfile@4.1.2",
  "main": "index.js",
  "scripts": {
    "test": "node test/contract.cjs"
  },
  "dependencies": {
    "proper-lockfile": "4.1.2"
  },
  "license": "MIT-0"
}

{
  "schemaVersion": 1,
  "goal": "verify proper-lockfile.unlockSync in pkg:npm/proper-lockfile@4.1.2",
  "kind": "HOW",
  "packages": [
    "pkg:npm/proper-lockfile@4.1.2"
  ],
  "symbols": [
    "proper-lockfile.unlockSync"
  ]
}

'use strict';

const assert = require('assert');
const fs = require('fs');
const path = require('path');
const os = require('os');
const lockfile = require('proper-lockfile');
const { releaseLockSync } = require('../index.js');

async function run() {
  const tmpDir = fs.mkdtempSync(path.join(os.tmpdir(), 'lockfile-test-'));
  try {
    const targetFile = path.join(tmpDir, 'test.txt');
    fs.writeFileSync(targetFile, 'content', 'utf8');

    // 1. unlockSync synchronously releases a lock acquired with lockSync
    lockfile.lockSync(targetFile);
    assert.strictEqual(lockfile.checkSync(targetFile), true, 'file should be locked after lockSync');
    releaseLockSync(targetFile);
    assert.strictEqual(lockfile.checkSync(targetFile), false, 'file should be unlocked after releaseLockSync');

    // 2. unlockSync synchronously releases a lock acquired with lock
    await lockfile.lock(targetFile);
    assert.strictEqual(lockfile.checkSync(targetFile), true, 'file should be locked after lock');
    lockfile.unlockSync(targetFile);
    assert.strictEqual(lockfile.checkSync(targetFile), false, 'file should be unlocked after unlockSync');

    // 3. unlockSync throws ENOTACQUIRED when called on a file not locked by the caller
    assert.throws(
      () => lockfile.unlockSync(targetFile),
      (err) => {
        assert.strictEqual(err.code, 'ENOTACQUIRED', 'error code must be ENOTACQUIRED');
        return true;
      },
      'unlockSync must throw ENOTACQUIRED when lock is not held'
    );

    // 4. unlockSync releases a lock with custom lockfilePath synchronously
    const customLockPath = path.join(tmpDir, 'custom.lock');
    lockfile.lockSync(targetFile, { lockfilePath: customLockPath });
    assert.strictEqual(fs.existsSync(customLockPath), true, 'custom lockfile path should exist');
    assert.strictEqual(lockfile.checkSync(targetFile, { lockfilePath: customLockPath }), true, 'checkSync should detect custom lock');
    lockfile.unlockSync(targetFile, { lockfilePath: customLockPath });
    assert.strictEqual(fs.existsSync(customLockPath), false, 'custom lockfile path should be removed');
    assert.strictEqual(lockfile.checkSync(targetFile, { lockfilePath: customLockPath }), false, 'checkSync should report unlocked');

    console.log('Contract tests passed successfully.');
  } finally {
    try {
      if (fs.existsSync(tmpDir)) {
        fs.rmSync(tmpDir, { recursive: true, force: true });
      }
    } catch (e) {
      // Ignore cleanup error
    }
  }
}

run().catch((err) => {
  console.error('Contract test failed:', err);
  process.exit(1);
});