p-map 7.1.1: pMapStop

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 p-map.pMapStop in pkg:npm/p-map@7.1.1
Kind: HOW

Use EXACTLY these public packages and versions:
  - pkg:npm/p-map@7.1.1
Demonstrate these symbols/APIs:
  - p-map.pMapStop

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:sha256:5eb7f6c7d62cbfe04afe8f6ecc5c923ee785f14da85dcfd52a58172a94e6f29d","contract":["pMapStop is a unique symbol with description 'stop' exported by p-map","returning pMapStop from a pMap mapper stops iteration, resolves with results before the stop in order, omits the stopping element, and closes the source iterator","returning pMapStop from pMapKeyed, pMapSettled, and pMapIterable stops iteration at the stopping element and keeps only preceding results"],"goal":"verify p-map.pMapStop in pkg:npm/p-map@7.1.1","kind":"HOW","packages":["pkg:npm/p-map@7.1.1"],"schemaVersion":1,"symbols":["p-map.pMapStop"]},"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/p-map@7.1.1"],"schemaVersion":1,"subject":"pkg:npm/p-map@7.1.1","symbols":["p-map.pMapStop"],"verifierAdapter":"node-typescript@1"}

{
  "name": "p-map-stop-sample",
  "version": "1.0.0",
  "lockfileVersion": 3,
  "requires": true,
  "packages": {
    "": {
      "name": "p-map-stop-sample",
      "version": "1.0.0",
      "dependencies": {
        "p-map": "7.1.1"
      }
    },
    "node_modules/p-map": {
      "version": "7.1.1",
      "resolved": "https://registry.npmjs.org/p-map/-/p-map-7.1.1.tgz",
      "integrity": "sha512-6Lh3jQPLthYujSrlw6ccWXBGZTkoTCz27Hd92g79LH/kjAbgoEu0t442cCCNbegPSJsA0lwDX8z0bcKtkpA32g==",
      "license": "MIT",
      "engines": {
        "node": ">=18"
      },
      "funding": {
        "url": "https://github.com/sponsors/sindresorhus"
      }
    }
  }
}

{
  "name": "p-map-stop-sample",
  "version": "1.0.0",
  "private": true,
  "type": "module",
  "scripts": {
    "test": "node test/contract.mjs"
  },
  "dependencies": {
    "p-map": "7.1.1"
  }
}

{
  "schemaVersion": 1,
  "goal": "verify p-map.pMapStop in pkg:npm/p-map@7.1.1",
  "kind": "HOW",
  "packages": [
    "pkg:npm/p-map@7.1.1"
  ],
  "symbols": [
    "p-map.pMapStop"
  ]
}

import assert from 'node:assert/strict';
import pMap, {pMapStop, pMapIterable, pMapKeyed, pMapSettled} from 'p-map';

// 1. Symbol identity
assert.equal(typeof pMapStop, 'symbol');
assert.equal(pMapStop.description, 'stop');

// 2. pMap stops at pMapStop, keeps preceding results in order, omits the stopping element, and closes the generator
let closed = false;
function * infiniteNumbers() {
	try {
		for (let i = 1; ; i++) {
			yield i;
		}
	} finally {
		closed = true;
	}
}

const mapped = await pMap(
	infiniteNumbers(),
	async n => (n === 4 ? pMapStop : n * 10),
	{concurrency: 2},
);
assert.deepEqual(mapped, [10, 20, 30]);
assert.equal(closed, true);

// 3. pMapKeyed stops at pMapStop and keeps only the keys before it
const keyedResult = await pMapKeyed(
	{a: 1, b: 2, c: 3, d: 4},
	async (value, key) => (key === 'c' ? pMapStop : value * 2),
	{concurrency: 1},
);
assert.deepEqual({...keyedResult}, {a: 2, b: 4});

// 4. pMapSettled stops at pMapStop and returns settled items before the stop
const settledResult = await pMapSettled(
	[1, 2, 3, 4],
	async value => {
		if (value === 2) {
			throw new Error('fail-2');
		}
		if (value === 3) {
			return pMapStop;
		}
		return value * 100;
	},
	{concurrency: 1},
);
assert.equal(settledResult.length, 2);
assert.deepEqual(settledResult[0], {status: 'fulfilled', value: 100});
assert.equal(settledResult[1].status, 'rejected');
assert.equal(settledResult[1].reason.message, 'fail-2');

// 5. pMapIterable stops yielding when a mapper returns pMapStop
const iterableResults = [];
for await (const item of pMapIterable([10, 20, 30, 40], async x => (x === 30 ? pMapStop : x + 1), {concurrency: 2})) {
	iterableResults.push(item);
}
assert.deepEqual(iterableResults, [11, 21]);