ip-address 10.1.0

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 pkg:npm/ip-address@10.1.0
Kind: HOW

Use EXACTLY these public packages and versions:
  - pkg:npm/ip-address@10.1.0

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:sha256:40cf264d33194d9f4664b57edfd94aab47513a7acd35b4c4ee1d2a9bd5bb10f2","contract":["Address4.isValid validates valid IPv4 addresses and rejects invalid strings","Address4 parses IPv4 address and CIDR subnet mask correctly","Address4 calculates startAddress and endAddress for a given subnet","Address4.isInSubnet determines whether an address belongs to the subnet","Address4 fromInteger and fromHex convert numbers and hex strings to IPv4","Address4 bigInt and fromBigInt convert IPv4 addresses to and from 32-bit integers","Address6.isValid validates valid IPv6 addresses and rejects invalid formats","Address6 formats canonical and correct compressed representations","Address6 calculates startAddress, endAddress, and subnet membership for IPv6 subnets","Address6 bigInt and fromBigInt convert IPv6 addresses to and from 128-bit integers","Address6 identifies special address types including loopback, link-local, and multicast","Address6.fromAddress4 creates IPv4-mapped IPv6 address and converts back via to4","Address4 throws AddressError on invalid IP input strings"],"goal":"verify pkg:npm/ip-address@10.1.0","kind":"HOW","packages":["pkg:npm/ip-address@10.1.0"],"schemaVersion":1},"contractCommand":["node","test/contract.cjs"],"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/ip-address@10.1.0"],"schemaVersion":1,"subject":"pkg:npm/ip-address@10.1.0","verifierAdapter":"node-typescript@1"}

{
  "name": "ip-address-sample",
  "version": "1.0.0",
  "lockfileVersion": 3,
  "requires": true,
  "packages": {
    "": {
      "name": "ip-address-sample",
      "version": "1.0.0",
      "dependencies": {
        "ip-address": "10.1.0"
      }
    },
    "node_modules/ip-address": {
      "version": "10.1.0",
      "resolved": "https://registry.npmjs.org/ip-address/-/ip-address-10.1.0.tgz",
      "integrity": "sha512-XXADHxXmvT9+CRxhXg56LJovE+bmWnEWB78LB83VZTprKTmaC5QfruXocxzTZ2Kl0DNwKuBdlIhjL8LeY8Sf8Q==",
      "license": "MIT",
      "engines": {
        "node": ">= 12"
      }
    }
  }
}

{
  "name": "ip-address-sample",
  "version": "1.0.0",
  "private": true,
  "description": "Verification sample for ip-address 10.1.0",
  "dependencies": {
    "ip-address": "10.1.0"
  }
}

{
  "schemaVersion": 1,
  "goal": "verify pkg:npm/ip-address@10.1.0",
  "kind": "HOW",
  "packages": [
    "pkg:npm/ip-address@10.1.0"
  ]
}

const assert = require("node:assert/strict");
const { Address4, Address6, AddressError } = require("ip-address");

// 1. Address4.isValid validates valid IPv4 addresses and rejects invalid strings
assert.equal(Address4.isValid("192.168.1.100"), true);
assert.equal(Address4.isValid("10.0.0.1"), true);
assert.equal(Address4.isValid("999.1.1.1"), false);
assert.equal(Address4.isValid("256.0.0.1"), false);
assert.equal(Address4.isValid("invalid-ip"), false);

// 2. Address4 parses IPv4 address and CIDR subnet mask correctly
const ipv4 = new Address4("192.168.1.100/24");
assert.equal(ipv4.address, "192.168.1.100/24");
assert.equal(ipv4.subnet, "/24");
assert.equal(ipv4.subnetMask, 24);

// 3. Address4 calculates startAddress and endAddress for a given subnet
assert.equal(ipv4.startAddress().correctForm(), "192.168.1.0");
assert.equal(ipv4.endAddress().correctForm(), "192.168.1.255");

// 4. Address4.isInSubnet determines whether an address belongs to the subnet
const member4 = new Address4("192.168.1.50");
const nonMember4 = new Address4("192.168.2.1");
assert.equal(member4.isInSubnet(ipv4), true);
assert.equal(nonMember4.isInSubnet(ipv4), false);

// 5. Address4 fromInteger and fromHex convert numbers and hex strings to IPv4
const v4FromInt = Address4.fromInteger(0x0a000001);
assert.equal(v4FromInt.correctForm(), "10.0.0.1");
const v4FromHex = Address4.fromHex("0a:00:00:01");
assert.equal(v4FromHex.correctForm(), "10.0.0.1");

// 6. Address4 bigInt and fromBigInt convert IPv4 addresses to and from 32-bit integers
const v4BigInt = ipv4.bigInt();
assert.equal(Address4.fromBigInt(v4BigInt).correctForm(), "192.168.1.100");

// 7. Address6.isValid validates valid IPv6 addresses and rejects invalid formats
assert.equal(Address6.isValid("2001:db8:85a3::8a2e:370:7334"), true);
assert.equal(Address6.isValid("::1"), true);
assert.equal(Address6.isValid("fe80:::1"), false);
assert.equal(Address6.isValid("not:valid:ipv6"), false);

// 8. Address6 formats canonical and correct compressed representations
const ipv6 = new Address6("2001:0db8:0000:0000:0000:0000:1428:57ab/64");
assert.equal(ipv6.canonicalForm(), "2001:0db8:0000:0000:0000:0000:1428:57ab");
assert.equal(ipv6.correctForm(), "2001:db8::1428:57ab");

// 9. Address6 calculates startAddress, endAddress, and subnet membership for IPv6 subnets
assert.equal(ipv6.startAddress().correctForm(), "2001:db8::");
assert.equal(ipv6.endAddress().correctForm(), "2001:db8::ffff:ffff:ffff:ffff");
const member6 = new Address6("2001:db8::1");
const nonMember6 = new Address6("2001:db9::1");
assert.equal(member6.isInSubnet(ipv6), true);
assert.equal(nonMember6.isInSubnet(ipv6), false);

// 10. Address6 bigInt and fromBigInt convert IPv6 addresses to and from 128-bit integers
const v6BigInt = ipv6.bigInt();
assert.equal(Address6.fromBigInt(v6BigInt).correctForm(), "2001:db8::1428:57ab");

// 11. Address6 identifies special address types including loopback, link-local, and multicast
assert.equal(new Address6("::1").isLoopback(), true);
assert.equal(new Address6("fe80::1").isLinkLocal(), true);
assert.equal(new Address6("ff00::1").isMulticast(), true);

// 12. Address6.fromAddress4 creates IPv4-mapped IPv6 address and converts back via to4
const v6Mapped = Address6.fromAddress4("192.168.1.1");
assert.equal(v6Mapped.is4(), true);
assert.equal(v6Mapped.to4().correctForm(), "192.168.1.1");

// 13. Address4 throws AddressError on invalid IP input strings
assert.throws(() => new Address4("not-an-ip"), (err) => {
  return err instanceof AddressError || err.name === "AddressError" || /Invalid/i.test(err.message);
});

console.log("Contract verified successfully.");