bare-stream 2.13.3: Readable

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.Readable 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.Readable

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:sha256:561f1e017045acdd69b9c69cc63b72e84f8726431135109d0e820b05f60dc2bf","contract":["Readable stream pushes chunks converted to buffers and emits data and end events","Readable stream supports async iteration over pushed chunks","Readable.from creates readable stream from arrays and async iterables","Readable unshift prepends data chunk before remaining chunks","Readable setEncoding decodes buffer chunks to strings with specified encoding","Readable toWeb converts to web ReadableStream and fromWeb reconstructs readable stream","Readable pause and resume controls stream consumption flow","Readable destroy with Error emits error and close events and marks stream destroyed"],"goal":"verify bare-stream.Readable in pkg:npm/bare-stream@2.13.3","kind":"HOW","packages":["pkg:npm/bare-stream@2.13.3"],"schemaVersion":1,"symbols":["bare-stream.Readable"]},"contractCommand":["node","test/contract.mjs"],"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/bare-stream@2.13.3"],"schemaVersion":1,"subject":"pkg:npm/bare-stream@2.13.3","symbols":["bare-stream.Readable"],"verifierAdapter":"node-typescript@1"}

{
  "name": "sample-bare-stream-readable",
  "version": "1.0.0",
  "lockfileVersion": 3,
  "requires": true,
  "packages": {
    "": {
      "name": "sample-bare-stream-readable",
      "version": "1.0.0",
      "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-readable",
  "version": "1.0.0",
  "type": "module",
  "private": true,
  "dependencies": {
    "bare-stream": "2.13.3"
  }
}

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

import assert from 'node:assert/strict';
import { Readable, isReadable, isEnded, isStream } from 'bare-stream';

// 1. Readable stream pushes chunks converted to buffers and emits data and end events
await new Promise((resolve, reject) => {
  const chunks = [];
  let index = 0;
  const items = ['chunk1', 'chunk2'];
  const readable = new Readable({
    read() {
      if (index < items.length) {
        this.push(items[index++]);
      } else {
        this.push(null);
      }
    }
  });

  assert.equal(isStream(readable), true);
  assert.equal(isReadable(readable), true);

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

  readable.on('end', () => {
    try {
      assert.deepEqual(chunks, ['chunk1', 'chunk2']);
      assert.equal(isEnded(readable), true);
      resolve();
    } catch (err) {
      reject(err);
    }
  });

  readable.on('error', reject);
});

// 2. Readable stream supports async iteration over pushed chunks
{
  const src = ['alpha', 'beta', 'gamma'];
  let idx = 0;
  const readable = new Readable({
    read() {
      if (idx < src.length) {
        this.push(src[idx++]);
      } else {
        this.push(null);
      }
    }
  });

  const collected = [];
  for await (const chunk of readable) {
    collected.push(chunk.toString());
  }

  assert.deepEqual(collected, ['alpha', 'beta', 'gamma']);
  assert.equal(isEnded(readable), true);
}

// 3. Readable.from creates readable stream from arrays and async iterables
{
  const arrayStream = Readable.from(['item1', 'item2']);
  const arrayChunks = [];
  for await (const chunk of arrayStream) {
    arrayChunks.push(chunk.toString());
  }
  assert.deepEqual(arrayChunks, ['item1', 'item2']);

  async function* generateItems() {
    yield 'gen1';
    yield 'gen2';
  }
  const generatorStream = Readable.from(generateItems());
  const genChunks = [];
  for await (const chunk of generatorStream) {
    genChunks.push(chunk.toString());
  }
  assert.deepEqual(genChunks, ['gen1', 'gen2']);
}

// 4. Readable unshift prepends data chunk before remaining chunks
await new Promise((resolve, reject) => {
  const readable = new Readable();
  readable.push('tail');
  readable.unshift('head');
  readable.push(null);

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

  readable.on('end', () => {
    try {
      assert.deepEqual(received, ['head', 'tail']);
      resolve();
    } catch (err) {
      reject(err);
    }
  });

  readable.on('error', reject);
});

// 5. Readable setEncoding decodes buffer chunks to strings with specified encoding
{
  const readable = Readable.from(['encoded-payload']);
  readable.setEncoding('utf8');

  let accumulated = '';
  for await (const chunk of readable) {
    assert.equal(typeof chunk, 'string');
    accumulated += chunk;
  }

  assert.equal(accumulated, 'encoded-payload');
}

// 6. Readable toWeb converts to web ReadableStream and fromWeb reconstructs readable stream
{
  const original = Readable.from(['web-chunk']);
  const webStream = Readable.toWeb(original);
  assert.ok(webStream);

  const reader = webStream.getReader();
  const readResult = await reader.read();
  assert.equal(readResult.value.toString(), 'web-chunk');
  const doneResult = await reader.read();
  assert.equal(doneResult.done, true);

  const roundtrip = Readable.fromWeb(Readable.toWeb(Readable.from(['stream-roundtrip'])));
  const roundtripChunks = [];
  for await (const chunk of roundtrip) {
    roundtripChunks.push(chunk.toString());
  }
  assert.deepEqual(roundtripChunks, ['stream-roundtrip']);
}

// 7. Readable pause and resume controls stream consumption flow
await new Promise((resolve, reject) => {
  let count = 0;
  const readable = new Readable({
    read() {
      if (count < 3) {
        this.push(`item-${count++}`);
      } else {
        this.push(null);
      }
    }
  });

  const received = [];
  readable.on('data', (chunk) => {
    received.push(chunk.toString());
    readable.pause();
    setTimeout(() => {
      readable.resume();
    }, 10);
  });

  readable.on('end', () => {
    try {
      assert.deepEqual(received, ['item-0', 'item-1', 'item-2']);
      resolve();
    } catch (err) {
      reject(err);
    }
  });

  readable.on('error', reject);
});

// 8. Readable destroy with Error emits error and close events and marks stream destroyed
await new Promise((resolve, reject) => {
  const readable = new Readable({
    read() {
      this.push('data');
    }
  });

  let errorEmitted = false;
  readable.on('error', (err) => {
    if (err.message === 'stream failure') {
      errorEmitted = true;
    }
  });

  readable.on('close', () => {
    try {
      assert.equal(errorEmitted, true);
      assert.equal(readable.destroyed, true);
      resolve();
    } catch (err) {
      reject(err);
    }
  });

  readable.destroy(new Error('stream failure'));
});