@types/deep-eql 4.0.2: types

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 @types/deep-eql.types in pkg:npm/%40types/deep-eql@4.0.2
Kind: HOW

Use EXACTLY these public packages and versions:
  - pkg:npm/%40types/deep-eql@4.0.2
Demonstrate these symbols/APIs:
  - @types/deep-eql.types

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:cc668571c9e0c9b0ffc94886689ec74b18e1c168a6d5fd633d52d92a155168ed","contract":["@types/deep-eql package.json exports index.d.ts type definitions file for version 4.0.2","@types/deep-eql index.d.ts exports deepEqual function accepting leftHandOperand, rightHandOperand, and optional options","@types/deep-eql index.d.ts defines MemoizeMap class extending WeakMap","@types/deep-eql index.d.ts defines DeepEqualOptions interface with comparator and memoize fields","@types/deep-eql DeepEqualOptions comparator signature accepts leftHandOperand and rightHandOperand returning boolean | null","@types/deep-eql DeepEqualOptions memoize accepts MemoizeMap or false"],"goal":"verify @types/deep-eql.types in pkg:npm/%40types/deep-eql@4.0.2","kind":"HOW","packages":["pkg:npm/%40types/deep-eql@4.0.2"],"schemaVersion":1,"symbols":["@types/deep-eql.types"]},"contractCommand":["node","test/contract.mjs"],"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/%40types/deep-eql@4.0.2"],"schemaVersion":1,"subject":"pkg:npm/%40types/deep-eql@4.0.2","symbols":["@types/deep-eql.types"],"verifierAdapter":"node-typescript@1"}

{
  "name": "sample-types-deep-eql",
  "version": "1.0.0",
  "lockfileVersion": 3,
  "requires": true,
  "packages": {
    "": {
      "name": "sample-types-deep-eql",
      "version": "1.0.0",
      "license": "MIT-0",
      "dependencies": {
        "@types/deep-eql": "4.0.2"
      }
    },
    "node_modules/@types/deep-eql": {
      "version": "4.0.2",
      "resolved": "https://registry.npmjs.org/@types/deep-eql/-/deep-eql-4.0.2.tgz",
      "integrity": "sha512-c9h9dVVMigMPc4bwTvC5dxqtqJZwQPePsWjPlpSOnojbor6pGqdk541lfA7AqFQr5pB1BRdq0juY9db81BwyFw==",
      "license": "MIT"
    }
  }
}

{
  "name": "sample-types-deep-eql",
  "version": "1.0.0",
  "type": "module",
  "private": true,
  "license": "MIT-0",
  "dependencies": {
    "@types/deep-eql": "4.0.2"
  }
}

{
  "schemaVersion": 1,
  "goal": "verify @types/deep-eql.types in pkg:npm/%40types/deep-eql@4.0.2",
  "kind": "HOW",
  "packages": [
    "pkg:npm/%40types/deep-eql@4.0.2"
  ],
  "symbols": [
    "@types/deep-eql.types"
  ]
}

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

const require = createRequire(import.meta.url);

// 1. @types/deep-eql package.json exports index.d.ts type definitions file for version 4.0.2
const pkgJson = require('@types/deep-eql/package.json');
assert.equal(pkgJson.name, '@types/deep-eql');
assert.equal(pkgJson.version, '4.0.2');
assert.equal(pkgJson.types, 'index.d.ts');

// 2. @types/deep-eql index.d.ts exports deepEqual function accepting leftHandOperand, rightHandOperand, and optional options
const dtsPath = require.resolve('@types/deep-eql/index.d.ts');
assert.ok(fs.existsSync(dtsPath));
const dtsContent = fs.readFileSync(dtsPath, 'utf8');

assert.ok(dtsContent.includes('export = deepEqual;'));
assert.ok(dtsContent.includes('declare function deepEqual<T1, T2>('));
assert.ok(dtsContent.includes('leftHandOperand: T1,'));
assert.ok(dtsContent.includes('rightHandOperand: T2,'));
assert.ok(dtsContent.includes('options?: deepEqual.DeepEqualOptions<T1, T2>,'));
assert.ok(dtsContent.includes('): boolean;'));

// 3. @types/deep-eql index.d.ts defines MemoizeMap class extending WeakMap
assert.ok(dtsContent.includes('declare namespace deepEqual {'));
assert.ok(dtsContent.includes('class MemoizeMap extends WeakMap<object, MemoizeMap | boolean> {}'));

// 4. @types/deep-eql index.d.ts defines DeepEqualOptions interface with comparator and memoize fields
assert.ok(dtsContent.includes('interface DeepEqualOptions<T1 = unknown, T2 = unknown> {'));
assert.ok(dtsContent.includes('comparator?: (leftHandOperand: T1, rightHandOperand: T2) => boolean | null;'));
assert.ok(dtsContent.includes('memoize?: MemoizeMap | false;'));

// 5. @types/deep-eql DeepEqualOptions comparator signature accepts leftHandOperand and rightHandOperand returning boolean | null
assert.ok(dtsContent.includes('(leftHandOperand: T1, rightHandOperand: T2) => boolean | null'));

// 6. @types/deep-eql DeepEqualOptions memoize accepts MemoizeMap or false
assert.ok(dtsContent.includes('memoize?: MemoizeMap | false;'));

console.log('Contract assertions passed.');