readable-stream 2.3.8

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/readable-stream@2.3.8
Kind: HOW

Use EXACTLY these public packages and versions:
  - pkg:npm/readable-stream@2.3.8

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:ae8e9569612bf7b1efa013ad8c0f11ee656b79cb0b536baf621ff1727f809b24","contract":["Readable stream emits data and end events when chunks are pushed and ended","Writable stream buffers written chunks and invokes callback upon finishing","Transform stream transforms chunks in _transform and passes output downstream","PassThrough stream passes input chunks directly through unmodified to reader","Duplex stream independently reads and writes data through duplex channels","Readable stream handles error events and propagates them to error listeners"],"goal":"verify pkg:npm/readable-stream@2.3.8","kind":"HOW","packages":["pkg:npm/readable-stream@2.3.8"],"schemaVersion":1},"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/readable-stream@2.3.8"],"schemaVersion":1,"subject":"pkg:npm/readable-stream@2.3.8","verifierAdapter":"node-typescript@1"}

{
  "name": "sample-readable-stream",
  "version": "1.0.0",
  "lockfileVersion": 3,
  "requires": true,
  "packages": {
    "": {
      "name": "sample-readable-stream",
      "version": "1.0.0",
      "dependencies": {
        "readable-stream": "2.3.8"
      }
    },
    "node_modules/core-util-is": {
      "version": "1.0.3",
      "resolved": "https://registry.npmjs.org/core-util-is/-/core-util-is-1.0.3.tgz",
      "integrity": "sha512-ZQBvi1DcpJ4GDqanjucZ2Hj3wEO5pZDS89BWbkcrvdxksJorwUDDZamX9ldFkp9aw2lmBDLgkObEA4DWNJ9FYQ==",
      "license": "MIT"
    },
    "node_modules/inherits": {
      "version": "2.0.4",
      "resolved": "https://registry.npmjs.org/inherits/-/inherits-2.0.4.tgz",
      "integrity": "sha512-k/vGaX4/Yla3WzyMCvTQOXYeIHvqOKtnqBduzTHpzpQZzAskKMhZ2K+EnBiSM9zGSoIFeMpXKxa4dYeZIQqewQ==",
      "license": "ISC"
    },
    "node_modules/isarray": {
      "version": "1.0.0",
      "resolved": "https://registry.npmjs.org/isarray/-/isarray-1.0.0.tgz",
      "integrity": "sha512-VLghIWNM6ELQzo7zwmcg0NmTVyWKYjvIeM83yjp0wRDTmUnrM678fQbcKBo6n2CJEF0szoG//ytg+TKla89ALQ==",
      "license": "MIT"
    },
    "node_modules/process-nextick-args": {
      "version": "2.0.1",
      "resolved": "https://registry.npmjs.org/process-nextick-args/-/process-nextick-args-2.0.1.tgz",
      "integrity": "sha512-3ouUOpQhtgrbOa17J7+uxOTpITYWaGP7/AhoR3+A+/1e9skrzelGi/dXzEYyvbxubEF6Wn2ypscTKiKJFFn1ag==",
      "license": "MIT"
    },
    "node_modules/readable-stream": {
      "version": "2.3.8",
      "resolved": "https://registry.npmjs.org/readable-stream/-/readable-stream-2.3.8.tgz",
      "integrity": "sha512-8p0AUk4XODgIewSi0l8Epjs+EVnWiK7NoDIEGU0HhE7+ZyY8D1IMY7odu5lRrFXGg71L15KG8QrPmum45RTtdA==",
      "license": "MIT",
      "dependencies": {
        "core-util-is": "~1.0.0",
        "inherits": "~2.0.3",
        "isarray": "~1.0.0",
        "process-nextick-args": "~2.0.0",
        "safe-buffer": "~5.1.1",
        "string_decoder": "~1.1.1",
        "util-deprecate": "~1.0.1"
      }
    },
    "node_modules/safe-buffer": {
      "version": "5.1.2",
      "resolved": "https://registry.npmjs.org/safe-buffer/-/safe-buffer-5.1.2.tgz",
      "integrity": "sha512-Gd2UZBJDkXlY7GbJxfsE8/nvKkUEU1G38c1siN6QP6a9PT9MmHB8GnpscSmMJSoF8LOIrt8ud/wPtojys4G6+g==",
      "license": "MIT"
    },
    "node_modules/string_decoder": {
      "version": "1.1.1",
      "resolved": "https://registry.npmjs.org/string_decoder/-/string_decoder-1.1.1.tgz",
      "integrity": "sha512-n/ShnvDi6FHbbVfviro+WojiFzv+s8MPMHBczVePfUpDJLwoLT0ht1l4YwBCbi8pJAveEEdnkHyPyTP/mzRfwg==",
      "license": "MIT",
      "dependencies": {
        "safe-buffer": "~5.1.0"
      }
    },
    "node_modules/util-deprecate": {
      "version": "1.0.2",
      "resolved": "https://registry.npmjs.org/util-deprecate/-/util-deprecate-1.0.2.tgz",
      "integrity": "sha512-EPD5q1uXyFxJpCrLnCc1nHnq3gOa6DZBocAIiI2TaSCA7VCJ1UJDMagCzIkXNsUYfD1daK//LTEQ8xiIbrHtcw==",
      "license": "MIT"
    }
  }
}

{
  "name": "sample-readable-stream",
  "version": "1.0.0",
  "type": "module",
  "private": true,
  "dependencies": {
    "readable-stream": "2.3.8"
  }
}

{
  "schemaVersion": 1,
  "goal": "verify pkg:npm/readable-stream@2.3.8",
  "kind": "HOW",
  "packages": [
    "pkg:npm/readable-stream@2.3.8"
  ]
}

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

// 1. Readable stream emits data and end events when chunks are pushed and ended
await new Promise((resolve, reject) => {
  const chunks = [];
  const readable = new Readable({
    read() {}
  });

  readable.on('data', (chunk) => {
    chunks.push(chunk.toString());
  });

  readable.on('end', () => {
    try {
      assert.deepEqual(chunks, ['hello', 'world']);
      resolve();
    } catch (err) {
      reject(err);
    }
  });

  readable.on('error', reject);

  readable.push('hello');
  readable.push('world');
  readable.push(null);
});

// 2. Writable stream buffers written chunks and invokes callback upon finishing
await new Promise((resolve, reject) => {
  const received = [];
  const writable = new Writable({
    write(chunk, encoding, callback) {
      received.push(chunk.toString());
      callback();
    }
  });

  writable.on('finish', () => {
    try {
      assert.deepEqual(received, ['alpha', 'beta']);
      resolve();
    } catch (err) {
      reject(err);
    }
  });

  writable.on('error', reject);

  writable.write('alpha');
  writable.write('beta');
  writable.end();
});

// 3. Transform stream transforms chunks in _transform and passes output downstream
await new Promise((resolve, reject) => {
  const upperTransform = new Transform({
    transform(chunk, encoding, callback) {
      callback(null, chunk.toString().toUpperCase());
    }
  });

  const output = [];
  upperTransform.on('data', (chunk) => {
    output.push(chunk.toString());
  });

  upperTransform.on('end', () => {
    try {
      assert.deepEqual(output, ['HELLO', 'WORLD']);
      resolve();
    } catch (err) {
      reject(err);
    }
  });

  upperTransform.on('error', reject);

  upperTransform.write('hello');
  upperTransform.write('world');
  upperTransform.end();
});

// 4. PassThrough stream passes input chunks directly through unmodified to reader
await new Promise((resolve, reject) => {
  const pass = new PassThrough();
  const output = [];

  pass.on('data', (chunk) => {
    output.push(chunk.toString());
  });

  pass.on('end', () => {
    try {
      assert.deepEqual(output, ['raw-data']);
      resolve();
    } catch (err) {
      reject(err);
    }
  });

  pass.on('error', reject);

  pass.write('raw-data');
  pass.end();
});

// 5. Duplex stream independently reads and writes data through duplex channels
await new Promise((resolve, reject) => {
  const readData = [];
  const writtenData = [];

  const duplex = new Duplex({
    read() {
      this.push('stream-read');
      this.push(null);
    },
    write(chunk, encoding, callback) {
      writtenData.push(chunk.toString());
      callback();
    }
  });

  duplex.on('data', (chunk) => {
    readData.push(chunk.toString());
  });

  let ended = false;
  let finished = false;

  function checkDone() {
    if (ended && finished) {
      try {
        assert.deepEqual(readData, ['stream-read']);
        assert.deepEqual(writtenData, ['stream-write']);
        resolve();
      } catch (err) {
        reject(err);
      }
    }
  }

  duplex.on('end', () => {
    ended = true;
    checkDone();
  });

  duplex.on('finish', () => {
    finished = true;
    checkDone();
  });

  duplex.on('error', reject);

  duplex.write('stream-write');
  duplex.end();
});

// 6. Readable stream handles error events and propagates them to error listeners
await new Promise((resolve, reject) => {
  const readable = new Readable({
    read() {
      this.emit('error', new Error('test-stream-error'));
    }
  });

  readable.on('error', (err) => {
    try {
      assert.equal(err.message, 'test-stream-error');
      resolve();
    } catch (e) {
      reject(e);
    }
  });

  readable.resume();
});