buffer-equal-constant-time 1.0.1

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/buffer-equal-constant-time@1.0.1
Kind: HOW

Use EXACTLY these public packages and versions:
  - pkg:npm/buffer-equal-constant-time@1.0.1
Constraints:
  - executionContext: node
Required runtime conditions:
  - ecosystem: npm
  - language: javascript
  - moduleSystem: cjs
  - packageManager: npm@10.9.8
  - runtime: node@22.23.2

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:fd959aba07b34886be2c4b1080b61f3c96bbbc07adf2e4d69d9ee84830f0d94b","constraints":{"executionContext":"node"},"contract":["bufferEq returns true for buffers with identical byte contents","bufferEq returns false for buffers with differing byte contents of equal length","bufferEq returns false for buffers of different lengths","bufferEq returns false when either argument is not a Buffer","install and restore attach and remove equal method on Buffer prototype"],"goal":"verify pkg:npm/buffer-equal-constant-time@1.0.1","kind":"HOW","packages":["pkg:npm/buffer-equal-constant-time@1.0.1"],"schemaVersion":1},"contractCommand":["node","test/contract.js"],"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/buffer-equal-constant-time@1.0.1"],"schemaVersion":1,"subject":"pkg:npm/buffer-equal-constant-time@1.0.1","verifierAdapter":"node-typescript@1"}

{
  "name": "sample-buffer-equal-constant-time",
  "version": "1.0.0",
  "lockfileVersion": 3,
  "requires": true,
  "packages": {
    "": {
      "name": "sample-buffer-equal-constant-time",
      "version": "1.0.0",
      "license": "MIT-0",
      "dependencies": {
        "buffer-equal-constant-time": "1.0.1"
      }
    },
    "node_modules/buffer-equal-constant-time": {
      "version": "1.0.1",
      "resolved": "https://registry.npmjs.org/buffer-equal-constant-time/-/buffer-equal-constant-time-1.0.1.tgz",
      "integrity": "sha512-zRpUiDwd/xk6ADqPMATG8vc9VPrkck7T07OIx0gnjmJAnHnTVXNQG3vfvWNuiZIkwu9KrKdA1iJKfsfTVxE6NA==",
      "license": "BSD-3-Clause"
    }
  }
}

{
  "name": "sample-buffer-equal-constant-time",
  "version": "1.0.0",
  "private": true,
  "description": "Clean-room verification sample for buffer-equal-constant-time",
  "main": "src/index.js",
  "scripts": {
    "test": "node test/contract.js"
  },
  "dependencies": {
    "buffer-equal-constant-time": "1.0.1"
  },
  "license": "MIT-0"
}

{
  "schemaVersion": 1,
  "goal": "verify pkg:npm/buffer-equal-constant-time@1.0.1",
  "kind": "HOW",
  "packages": [
    "pkg:npm/buffer-equal-constant-time@1.0.1"
  ],
  "constraints": {
    "executionContext": "node"
  },
  "runtimeConditions": {
    "ecosystem": "npm",
    "language": "javascript",
    "moduleSystem": "cjs",
    "packageManager": "npm@10.9.8",
    "runtime": "node@22.23.2"
  }
}

const bufferEq = require("buffer-equal-constant-time");

function compareBuffers(a, b) {
  return bufferEq(a, b);
}

function installBufferEqual() {
  bufferEq.install();
}

function restoreBufferEqual() {
  bufferEq.restore();
}

module.exports = {
  bufferEq,
  compareBuffers,
  installBufferEqual,
  restoreBufferEqual
};

const assert = require("node:assert");
const { Buffer } = require("node:buffer");
const bufferEq = require("buffer-equal-constant-time");
const {
  compareBuffers,
  installBufferEqual,
  restoreBufferEqual
} = require("../src/index.js");

// 1. bufferEq returns true for buffers with identical byte contents
const bufA1 = Buffer.from("secure-api-key-12345");
const bufA2 = Buffer.from("secure-api-key-12345");
assert.strictEqual(bufferEq(bufA1, bufA2), true, "Identical buffers must return true");
assert.strictEqual(compareBuffers(bufA1, bufA2), true, "compareBuffers wrapper must return true for identical buffers");

// 2. bufferEq returns false for buffers with differing byte contents of equal length
const bufB1 = Buffer.from("secure-api-key-12345");
const bufB2 = Buffer.from("secure-api-key-99999");
assert.strictEqual(bufferEq(bufB1, bufB2), false, "Buffers of same length with different content must return false");
assert.strictEqual(compareBuffers(bufB1, bufB2), false, "compareBuffers wrapper must return false for differing buffers");

// 3. bufferEq returns false for buffers of different lengths
const bufC1 = Buffer.from("short");
const bufC2 = Buffer.from("longer-string");
assert.strictEqual(bufferEq(bufC1, bufC2), false, "Buffers of different length must return false");

// 4. bufferEq returns false when either argument is not a Buffer
assert.strictEqual(bufferEq("not-a-buffer", bufA1), false, "First argument non-buffer must return false");
assert.strictEqual(bufferEq(bufA1, null), false, "Second argument null must return false");
assert.strictEqual(bufferEq({}, {}), false, "Non-buffer objects must return false");

// 5. install and restore attach and remove equal method on Buffer prototype
const originalBufferEqual = Buffer.prototype.equal;
installBufferEqual();
assert.strictEqual(typeof Buffer.prototype.equal, "function", "Buffer.prototype.equal must be defined after install");
assert.strictEqual(bufA1.equal(bufA2), true, "bufA1.equal(bufA2) must return true");
assert.strictEqual(bufA1.equal(bufB2), false, "bufA1.equal(bufB2) must return false");

restoreBufferEqual();
assert.strictEqual(Buffer.prototype.equal, originalBufferEqual, "Buffer.prototype.equal must be restored");

console.log("All buffer-equal-constant-time contract tests passed successfully.");