semver 5.7.2: prerelease

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 semver.prerelease in pkg:npm/semver@5.7.2
Kind: HOW

Use EXACTLY these public packages and versions:
  - pkg:npm/semver@5.7.2
Demonstrate these symbols/APIs:
  - semver.prerelease

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:e2a64d310e2e066f6706bcf1cd2e1575c5964dd7468f31cb1aa0af499a420110","contract":["prerelease returns array of identifiers with numeric components as numbers for prerelease versions","prerelease returns null for valid release versions without prerelease tag","prerelease handles leading v prefix and ignores build metadata","prerelease returns null for invalid strings null and undefined","prerelease supports loose mode boolean and options object for loose version strings"],"goal":"verify semver.prerelease in pkg:npm/semver@5.7.2","kind":"HOW","packages":["pkg:npm/semver@5.7.2"],"schemaVersion":1,"symbols":["semver.prerelease"]},"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/semver@5.7.2"],"schemaVersion":1,"subject":"pkg:npm/semver@5.7.2","symbols":["semver.prerelease"],"verifierAdapter":"node-typescript@1"}

{
  "name": "sample-semver-prerelease",
  "version": "1.0.0",
  "lockfileVersion": 3,
  "requires": true,
  "packages": {
    "": {
      "name": "sample-semver-prerelease",
      "version": "1.0.0",
      "license": "MIT-0",
      "dependencies": {
        "semver": "5.7.2"
      }
    },
    "node_modules/semver": {
      "version": "5.7.2",
      "resolved": "https://registry.npmjs.org/semver/-/semver-5.7.2.tgz",
      "integrity": "sha512-cBznnQ9KjJqU67B52RMC65CMarK2600WFnbkcaiwWq3xy/5haFJlshgnpjovMVJ+Hff49d8GEn0b87C5pDQ10g==",
      "license": "ISC",
      "bin": {
        "semver": "bin/semver"
      }
    }
  }
}

{
  "name": "sample-semver-prerelease",
  "version": "1.0.0",
  "private": true,
  "description": "Clean-room code sample for semver.prerelease in semver@5.7.2",
  "main": "src/index.js",
  "license": "MIT-0",
  "dependencies": {
    "semver": "5.7.2"
  }
}

{
  "schemaVersion": 1,
  "goal": "verify semver.prerelease in pkg:npm/semver@5.7.2",
  "kind": "HOW",
  "packages": [
    "pkg:npm/semver@5.7.2"
  ],
  "symbols": [
    "semver.prerelease"
  ]
}

const semver = require('semver');

/**
 * Parses the prerelease components of a version string.
 * Returns an array of identifiers (strings and numbers) if a prerelease tag exists,
 * or null if the version is a stable release without prerelease tag or invalid.
 *
 * @param {string} version - The version string to parse.
 * @param {boolean|object} [loose=false] - Whether to allow loose parsing.
 * @returns {Array<string|number>|null} Array of prerelease components or null.
 */
function getPrerelease(version, loose = false) {
  return semver.prerelease(version, loose);
}

/**
 * Checks whether a given semantic version is a prerelease version.
 *
 * @param {string} version - The version string to check.
 * @param {boolean|object} [loose=false] - Whether to allow loose parsing.
 * @returns {boolean} True if the version has prerelease components, false otherwise.
 */
function isPrerelease(version, loose = false) {
  const parsed = semver.prerelease(version, loose);
  return Array.isArray(parsed) && parsed.length > 0;
}

module.exports = {
  semver,
  prerelease: semver.prerelease,
  getPrerelease,
  isPrerelease
};

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

const require = createRequire(import.meta.url);
const {
  semver,
  prerelease,
  getPrerelease,
  isPrerelease
} = require('../src/index.js');

async function runContractTests() {
  // 1. prerelease returns array of identifiers with numeric components as numbers for prerelease versions
  assert.equal(typeof semver.prerelease, 'function', 'semver.prerelease must be a function');
  assert.equal(typeof prerelease, 'function', 'prerelease must be a function');
  assert.deepEqual(prerelease('1.2.3-alpha.1'), ['alpha', 1], 'numeric parts must be parsed as numbers');
  assert.deepEqual(prerelease('1.0.0-0.3.7'), [0, 3, 7], 'numeric-only prerelease parts must be numbers');
  assert.deepEqual(prerelease('1.0.0-x.7.z.92'), ['x', 7, 'z', 92], 'mixed parts must retain correct types');
  assert.deepEqual(getPrerelease('2.0.0-beta'), ['beta'], 'string-only prerelease must return array with string');
  assert.equal(isPrerelease('1.2.3-alpha.1'), true, 'isPrerelease helper returns true for prerelease');

  // 2. prerelease returns null for valid release versions without prerelease tag
  assert.equal(prerelease('1.0.0'), null, 'release version without prerelease returns null, not empty array');
  assert.equal(prerelease('2.4.10'), null, 'standard version returns null');
  assert.equal(getPrerelease('0.1.0'), null, 'getPrerelease helper returns null for release version');
  assert.equal(isPrerelease('1.0.0'), false, 'isPrerelease helper returns false for release version');

  // 3. prerelease handles leading v prefix and ignores build metadata
  assert.deepEqual(prerelease('v1.2.3-rc.1'), ['rc', 1], 'leading v prefix must be handled');
  assert.deepEqual(prerelease('1.2.3-beta.2+build.184'), ['beta', 2], 'build metadata must be ignored');
  assert.deepEqual(prerelease('v2.0.0-alpha.5+20200101'), ['alpha', 5], 'v prefix and build metadata handled together');

  // 4. prerelease returns null for invalid strings null and undefined
  assert.equal(prerelease('invalid-version'), null, 'invalid string returns null');
  assert.equal(prerelease(''), null, 'empty string returns null');
  assert.equal(prerelease(null), null, 'null input returns null');
  assert.equal(prerelease(undefined), null, 'undefined input returns null');
  assert.equal(isPrerelease('not-a-version'), false, 'isPrerelease returns false for invalid version');

  // 5. prerelease supports loose mode boolean and options object for loose version strings
  assert.equal(prerelease('v 1.2.3-alpha.1'), null, 'strict mode rejects loose version with space');
  assert.deepEqual(prerelease('v 1.2.3-alpha.1', true), ['alpha', 1], 'loose boolean mode parses loose version');
  assert.deepEqual(prerelease('v 1.2.3-alpha.1', { loose: true }), ['alpha', 1], 'loose options object mode parses loose version');
  assert.deepEqual(getPrerelease('v 2.0.0-rc.3', true), ['rc', 3], 'getPrerelease helper supports loose mode');
  assert.equal(isPrerelease('v 1.0.0-beta.1', true), true, 'isPrerelease helper supports loose mode');

  console.log('All semver.prerelease contract tests passed successfully.');
}

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