bare-stream 2.13.3: finished

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 bare-stream.finished in pkg:npm/bare-stream@2.13.3
Kind: HOW

Use EXACTLY these public packages and versions:
  - pkg:npm/bare-stream@2.13.3
Demonstrate these symbols/APIs:
  - bare-stream.finished

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:sha256:657ff70cb0277b359389a478510ca7bdf52a12aea107a0357c245fff129692db","contract":["finished calls callback with null when a Readable stream completes consumption and closes","finished calls callback with null when a Writable stream writes all chunks, ends, and closes","finished calls callback with null when a Transform stream completes and closes","finished captures stream error and passes the exact error to callback when a stream is destroyed with an error","finished invokes callback immediately with the stream error when called on an already destroyed stream","finished returns a detach function that removes completion listeners and prevents callback invocation","finished with cleanup option true removes all attached close and error event listeners upon completion"],"goal":"verify bare-stream.finished in pkg:npm/bare-stream@2.13.3","kind":"HOW","packages":["pkg:npm/bare-stream@2.13.3"],"schemaVersion":1,"symbols":["bare-stream.finished"]},"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/bare-stream@2.13.3"],"schemaVersion":1,"subject":"pkg:npm/bare-stream@2.13.3","symbols":["bare-stream.finished"],"verifierAdapter":"node-typescript@1"}

{
  "name": "sample-bare-stream-finished",
  "version": "1.0.0",
  "lockfileVersion": 3,
  "requires": true,
  "packages": {
    "": {
      "name": "sample-bare-stream-finished",
      "version": "1.0.0",
      "license": "MIT-0",
      "dependencies": {
        "bare-stream": "2.13.3"
      }
    },
    "node_modules/b4a": {
      "version": "1.8.1",
      "resolved": "https://registry.npmjs.org/b4a/-/b4a-1.8.1.tgz",
      "integrity": "sha512-aiqre1Nr0B/6DgE2N5vwTc+2/oQZ4Wh1t4NznYY4E00y8LCt6NqdRv81so00oo27D8MVKTpUa/MwUUtBLXCoDw==",
      "license": "Apache-2.0",
      "peerDependencies": {
        "react-native-b4a": "*"
      },
      "peerDependenciesMeta": {
        "react-native-b4a": {
          "optional": true
        }
      }
    },
    "node_modules/bare-events": {
      "version": "2.9.2",
      "resolved": "https://registry.npmjs.org/bare-events/-/bare-events-2.9.2.tgz",
      "integrity": "sha512-AIPKioV7/Y/8KfZ3AAhjPJxLLbY49S64Ym5DakZlUg75qQiTgUq9hEJoEwa4eUezPUlXRy/i5NpsKvo9jgKmoA==",
      "license": "Apache-2.0",
      "peerDependencies": {
        "bare-abort-controller": "*"
      },
      "peerDependenciesMeta": {
        "bare-abort-controller": {
          "optional": true
        }
      }
    },
    "node_modules/bare-stream": {
      "version": "2.13.3",
      "resolved": "https://registry.npmjs.org/bare-stream/-/bare-stream-2.13.3.tgz",
      "integrity": "sha512-Kc+brLqvEqGkjyfiwJmImAOqLZL7OsoLKuavx+hJjgVV3nLTOjloJyPMFxjUPerGGHrNH0fLU06jjykMLWrERQ==",
      "license": "Apache-2.0",
      "dependencies": {
        "b4a": "^1.8.1",
        "streamx": "^2.25.0",
        "teex": "^1.0.1"
      },
      "peerDependencies": {
        "bare-abort-controller": "*",
        "bare-buffer": "*",
        "bare-events": "*"
      },
      "peerDependenciesMeta": {
        "bare-abort-controller": {
          "optional": true
        },
        "bare-buffer": {
          "optional": true
        },
        "bare-events": {
          "optional": true
        }
      }
    },
    "node_modules/events-universal": {
      "version": "1.0.1",
      "resolved": "https://registry.npmjs.org/events-universal/-/events-universal-1.0.1.tgz",
      "integrity": "sha512-LUd5euvbMLpwOF8m6ivPCbhQeSiYVNb8Vs0fQ8QjXo0JTkEHpz8pxdQf0gStltaPpw0Cca8b39KxvK9cfKRiAw==",
      "license": "Apache-2.0",
      "dependencies": {
        "bare-events": "^2.7.0"
      }
    },
    "node_modules/fast-fifo": {
      "version": "1.3.2",
      "resolved": "https://registry.npmjs.org/fast-fifo/-/fast-fifo-1.3.2.tgz",
      "integrity": "sha512-/d9sfos4yxzpwkDkuN7k2SqFKtYNmCTzgfEpz82x34IM9/zc8KGxQoXg1liNC/izpRM/MBdt44Nmx41ZWqk+FQ==",
      "license": "MIT"
    },
    "node_modules/streamx": {
      "version": "2.28.1",
      "resolved": "https://registry.npmjs.org/streamx/-/streamx-2.28.1.tgz",
      "integrity": "sha512-zEzXb0s5Cds7tqMH6rhZ05lcJydCWiQPEwiNngVqzsxCc962vLY4Uw+mW7od8kDH258k2Uz/JrOkdIAAhSh9VA==",
      "license": "MIT",
      "dependencies": {
        "events-universal": "^1.0.0",
        "fast-fifo": "^1.3.2",
        "text-decoder": "^1.1.0"
      }
    },
    "node_modules/teex": {
      "version": "1.0.1",
      "resolved": "https://registry.npmjs.org/teex/-/teex-1.0.1.tgz",
      "integrity": "sha512-eYE6iEI62Ni1H8oIa7KlDU6uQBtqr4Eajni3wX7rpfXD8ysFx8z0+dri+KWEPWpBsxXfxu58x/0jvTVT1ekOSg==",
      "license": "MIT",
      "dependencies": {
        "streamx": "^2.12.5"
      }
    },
    "node_modules/text-decoder": {
      "version": "1.2.7",
      "resolved": "https://registry.npmjs.org/text-decoder/-/text-decoder-1.2.7.tgz",
      "integrity": "sha512-vlLytXkeP4xvEq2otHeJfSQIRyWxo/oZGEbXrtEEF9Hnmrdly59sUbzZ/QgyWuLYHctCHxFF4tRQZNQ9k60ExQ==",
      "license": "Apache-2.0",
      "dependencies": {
        "b4a": "^1.6.4"
      }
    }
  }
}

{
  "name": "sample-bare-stream-finished",
  "version": "1.0.0",
  "type": "module",
  "private": true,
  "license": "MIT-0",
  "dependencies": {
    "bare-stream": "2.13.3"
  }
}

{
  "schemaVersion": 1,
  "goal": "verify bare-stream.finished in pkg:npm/bare-stream@2.13.3",
  "kind": "HOW",
  "packages": [
    "pkg:npm/bare-stream@2.13.3"
  ],
  "symbols": [
    "bare-stream.finished"
  ]
}

import assert from 'node:assert/strict';
import { finished, Readable, Writable, PassThrough, Transform } from 'bare-stream';

// 1. Readable stream completion via finished()
{
  const stream = Readable.from(['chunk1', 'chunk2']);
  let called = false;
  let receivedError = undefined;

  finished(stream, (err) => {
    called = true;
    receivedError = err;
  });

  for await (const _ of stream) {
    // consume stream to completion
  }

  if (!stream.destroyed) {
    await new Promise((resolve) => stream.once('close', resolve));
  }

  assert.equal(called, true, 'finished callback must be called when Readable finishes');
  assert.equal(receivedError, null, 'finished callback error must be null on normal Readable completion');
}

// 2. Writable stream completion via finished()
{
  const chunks = [];
  const stream = new Writable({
    write(data, encoding, cb) {
      chunks.push(data);
      cb(null);
    }
  });

  let called = false;
  let receivedError = undefined;

  finished(stream, (err) => {
    called = true;
    receivedError = err;
  });

  stream.write('hello');
  stream.write('world');
  stream.end();

  await new Promise((resolve) => stream.once('close', resolve));

  assert.equal(called, true, 'finished callback must be called when Writable finishes');
  assert.equal(receivedError, null, 'finished callback error must be null on normal Writable completion');
  assert.equal(chunks.length, 2, 'all chunks must be written before completion');
}

// 3. Transform stream completion via finished()
{
  const stream = new Transform({
    transform(data, encoding, cb) {
      cb(null, data);
    }
  });

  let called = false;
  let receivedError = undefined;

  finished(stream, (err) => {
    called = true;
    receivedError = err;
  });

  stream.resume();
  stream.write('ping');
  stream.end();

  await new Promise((resolve) => stream.once('close', resolve));

  assert.equal(called, true, 'finished callback must be called when Transform finishes');
  assert.equal(receivedError, null, 'finished callback error must be null on normal Transform completion');
}

// 4. Stream destroyed with an error triggers callback with the error
{
  const stream = new PassThrough();
  const testError = new Error('stream failure');

  let called = false;
  let receivedError = null;

  finished(stream, (err) => {
    called = true;
    receivedError = err;
  });

  stream.destroy(testError);
  await new Promise((resolve) => stream.once('close', resolve));

  assert.equal(called, true, 'finished callback must be called on stream error destroy');
  assert.equal(receivedError, testError, 'finished callback must receive the exact destruction error');
}

// 5. Already destroyed stream invokes callback immediately
{
  const stream = new PassThrough();
  stream.on('error', () => {}); // protect against unhandled error before listener
  const testError = new Error('pre-destroyed error');
  stream.destroy(testError);

  await new Promise((resolve) => stream.once('close', resolve));
  assert.equal(stream.destroyed, true, 'stream must be in destroyed state');

  let called = false;
  let receivedError = null;

  finished(stream, (err) => {
    called = true;
    receivedError = err;
  });

  assert.equal(called, true, 'finished callback must be called immediately for already destroyed stream');
  assert.equal(receivedError, testError, 'finished callback must receive error from destroyed stream');
}

// 6. Detach function cancels listener registration
{
  const stream = new PassThrough();
  let called = false;

  const detach = finished(stream, () => {
    called = true;
  });

  assert.equal(typeof detach, 'function', 'finished must return a detach function');
  detach();

  stream.destroy();
  await new Promise((resolve) => stream.once('close', resolve));

  assert.equal(called, false, 'finished callback must not be invoked after calling detach()');
}

// 7. Cleanup option ({ cleanup: true }) cleans up listeners upon completion
{
  const stream = new PassThrough();
  let called = false;

  finished(stream, { cleanup: true }, (err) => {
    called = true;
  });

  stream.destroy();
  await new Promise((resolve) => stream.once('close', resolve));

  assert.equal(called, true, 'finished callback must be called with cleanup option');
  assert.equal(stream.listenerCount('close'), 0, 'close listeners must be removed when cleanup: true');
  assert.equal(stream.listenerCount('error'), 0, 'error listeners must be removed when cleanup: true');
}

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