imurmurhash 0.1.4: MurmurHash3

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/imurmurhash@0.1.4
Kind: HOW

Use EXACTLY these public packages and versions:
  - pkg:npm/imurmurhash@0.1.4
Demonstrate these symbols/APIs:
  - MurmurHash3

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:sha256:62ad60482268486806e9b4fb91e215987877dadf36ba2cb2067b5b3101f19f51","contract":["assert MurmurHash3 creates a hash instance and calculates 32-bit unsigned integer hash","assert MurmurHash3 supports incremental string hashing matching single-pass calculation","assert MurmurHash3 accepts custom seed affecting hash output","assert MurmurHash3 supports reset method for reusing instance with optional new seed","assert MurmurHash3 without new uses cached instance and resets on each call"],"goal":"verify pkg:npm/imurmurhash@0.1.4","kind":"HOW","packages":["pkg:npm/imurmurhash@0.1.4"],"schemaVersion":1,"symbols":["MurmurHash3"]},"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/imurmurhash@0.1.4"],"schemaVersion":1,"subject":"pkg:npm/imurmurhash@0.1.4","symbols":["MurmurHash3"],"verifierAdapter":"node-typescript@1"}

{
  "name": "sample-imurmurhash",
  "version": "1.0.0",
  "lockfileVersion": 3,
  "requires": true,
  "packages": {
    "": {
      "name": "sample-imurmurhash",
      "version": "1.0.0",
      "license": "MIT-0",
      "dependencies": {
        "imurmurhash": "0.1.4"
      }
    },
    "node_modules/imurmurhash": {
      "version": "0.1.4",
      "resolved": "https://registry.npmjs.org/imurmurhash/-/imurmurhash-0.1.4.tgz",
      "integrity": "sha512-JmXMZ6wuvDmLiHEml9ykzqO6lwFbof0GG4IkcGaENdCRDDmMVnny7s5HsIgHCbaq0w2MyPhDqkhTUgS2LU2PHA==",
      "license": "MIT",
      "engines": {
        "node": ">=0.8.19"
      }
    }
  }
}

{
  "name": "sample-imurmurhash",
  "version": "1.0.0",
  "type": "module",
  "license": "MIT-0",
  "dependencies": {
    "imurmurhash": "0.1.4"
  }
}

{
  "schemaVersion": 1,
  "goal": "verify pkg:npm/imurmurhash@0.1.4",
  "kind": "HOW",
  "packages": [
    "pkg:npm/imurmurhash@0.1.4"
  ],
  "symbols": [
    "MurmurHash3"
  ]
}

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

const require = createRequire(import.meta.url);
const MurmurHash3 = require('imurmurhash');

// 1. Export verification
assert.equal(typeof MurmurHash3, 'function', 'MurmurHash3 must be a function');

// 2. Hash calculation returning 32-bit unsigned integer
const h1 = MurmurHash3('hello world').result();
assert.equal(typeof h1, 'number');
assert.equal(Number.isInteger(h1), true);
assert.equal(h1 >= 0 && h1 <= 0xffffffff, true);
assert.equal(h1, 1586663183);

// 3. Incremental string hashing matches single-pass calculation
const full = 'The quick brown fox jumps over the lazy dog';
const singlePass = new MurmurHash3(full).result();

const incremental = new MurmurHash3()
  .hash('The quick ')
  .hash('brown fox ')
  .hash('jumps over ')
  .hash('the lazy dog')
  .result();

assert.equal(incremental, singlePass);

// 4. Custom seed parameter alters hash output
const seedVal = 42;
const unseeded = new MurmurHash3('sample text').result();
const seeded = new MurmurHash3('sample text', seedVal).result();
assert.equal(typeof seeded, 'number');
assert.notEqual(seeded, unseeded);

const seededIncremental = new MurmurHash3(undefined, seedVal).hash('sample text').result();
assert.equal(seededIncremental, seeded);

// 5. Reset method clears state and allows reuse with optional seed
const reusable = new MurmurHash3('initial');
reusable.reset();
reusable.hash('new string');
assert.equal(reusable.result(), new MurmurHash3('new string').result());

reusable.reset(999);
reusable.hash('new string');
assert.equal(reusable.result(), new MurmurHash3('new string', 999).result());

// 6. Function call without new uses cached singleton instance
const state1 = MurmurHash3('test-string');
assert.equal(state1.result(), new MurmurHash3('test-string').result());

const state2 = MurmurHash3('another-string');
assert.equal(state2.result(), new MurmurHash3('another-string').result());
assert.equal(state1, state2);

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