fs-extra 8.1.0: copy

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 fs-extra.copy in pkg:npm/fs-extra@8.1.0
Kind: HOW

Use EXACTLY these public packages and versions:
  - pkg:npm/fs-extra@8.1.0
Demonstrate these symbols/APIs:
  - fs-extra.copy
Constraints:
  - executionContext: node
Required runtime conditions:
  - ecosystem: npm
  - language: javascript
  - moduleSystem: cjs
  - packageManager: npm@10.9.8
  - runtime: node@22.23.2

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:sha256:63a9d9122f1935476fc65413560c35d5b19a079e28fc1bfcd3402bba407e12e0","constraints":{"executionContext":"node"},"contract":["fs.copy asynchronously copies a single file to a target destination, creating parent directories if needed","fs.copy recursively copies an entire directory hierarchy preserving structure and content","fs.copy supports a filter function to selectively copy files and directories","fs.copy rejects with an error when overwrite is false and errorOnExist is true if destination exists","fs.copySync synchronously copies directory structures and contents","fs.copy preserves timestamps when preserveTimestamps option is true"],"goal":"verify fs-extra.copy in pkg:npm/fs-extra@8.1.0","kind":"HOW","packages":["pkg:npm/fs-extra@8.1.0"],"schemaVersion":1,"symbols":["fs-extra.copy"]},"contractCommand":["node","test/contract.cjs"],"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/fs-extra@8.1.0"],"schemaVersion":1,"subject":"pkg:npm/fs-extra@8.1.0","symbols":["fs-extra.copy"],"verifierAdapter":"node-typescript@1"}

{
  "name": "sample-fs-extra-copy",
  "version": "1.0.0",
  "lockfileVersion": 3,
  "requires": true,
  "packages": {
    "": {
      "name": "sample-fs-extra-copy",
      "version": "1.0.0",
      "license": "MIT-0",
      "dependencies": {
        "fs-extra": "8.1.0"
      }
    },
    "node_modules/fs-extra": {
      "version": "8.1.0",
      "resolved": "https://registry.npmjs.org/fs-extra/-/fs-extra-8.1.0.tgz",
      "integrity": "sha512-yhlQgA6mnOJUKOsRUFsgJdQCvkKhcz8tlZG5HBQfReYZy46OwLcY+Zia0mtdHsOo9y/hP+CxMN0TU9QxoOtG4g==",
      "license": "MIT",
      "dependencies": {
        "graceful-fs": "^4.2.0",
        "jsonfile": "^4.0.0",
        "universalify": "^0.1.0"
      },
      "engines": {
        "node": ">=6 <7 || >=8"
      }
    },
    "node_modules/graceful-fs": {
      "version": "4.2.11",
      "resolved": "https://registry.npmjs.org/graceful-fs/-/graceful-fs-4.2.11.tgz",
      "integrity": "sha512-RbJ5/jmFcNNCcDV5o9eTnBLJ/HszWV0P73bc+Ff4nS/rJj+YaS6IGyiOL0VoBYX+l1Wrl3k63h/KrH+nhJ0XvQ==",
      "license": "ISC"
    },
    "node_modules/jsonfile": {
      "version": "4.0.0",
      "resolved": "https://registry.npmjs.org/jsonfile/-/jsonfile-4.0.0.tgz",
      "integrity": "sha512-m6F1R3z8jjlf2imQHS2Qez5sjKWQzbuuhuJ/FKYFRZvPE3PuHcSMVZzfsLhGVOkfd20obL5SWEBew5ShlquNxg==",
      "license": "MIT",
      "optionalDependencies": {
        "graceful-fs": "^4.1.6"
      }
    },
    "node_modules/universalify": {
      "version": "0.1.2",
      "resolved": "https://registry.npmjs.org/universalify/-/universalify-0.1.2.tgz",
      "integrity": "sha512-rBJeI5CXAlmy1pV+617WB9J63U6XcazHHF2f2dbJix4XzpUF0RS3Zbj0FGIOCAva5P/d/GBOYaACQ1w+0azUkg==",
      "license": "MIT",
      "engines": {
        "node": ">= 4.0.0"
      }
    }
  }
}

{
  "name": "sample-fs-extra-copy",
  "version": "1.0.0",
  "private": true,
  "description": "verify fs-extra.copy in pkg:npm/fs-extra@8.1.0",
  "main": "src/index.js",
  "scripts": {
    "test": "node test/contract.cjs"
  },
  "dependencies": {
    "fs-extra": "8.1.0"
  },
  "license": "MIT-0"
}

{
  "schemaVersion": 1,
  "goal": "verify fs-extra.copy in pkg:npm/fs-extra@8.1.0",
  "kind": "HOW",
  "packages": [
    "pkg:npm/fs-extra@8.1.0"
  ],
  "symbols": [
    "fs-extra.copy"
  ],
  "constraints": {
    "executionContext": "node"
  },
  "runtimeConditions": {
    "ecosystem": "npm",
    "language": "javascript",
    "moduleSystem": "cjs",
    "packageManager": "npm@10.9.8",
    "runtime": "node@22.23.2"
  }
}

const fs = require('fs-extra');

/**
 * Asynchronously copies a file or directory.
 * @param {string} src - Source path.
 * @param {string} dest - Destination path.
 * @param {object} [options] - Copy options.
 * @returns {Promise<void>}
 */
async function copyPath(src, dest, options = {}) {
  return fs.copy(src, dest, options);
}

/**
 * Synchronously copies a file or directory.
 * @param {string} src - Source path.
 * @param {string} dest - Destination path.
 * @param {object} [options] - Copy options.
 */
function copyPathSync(src, dest, options = {}) {
  fs.copySync(src, dest, options);
}

module.exports = {
  fs,
  copyPath,
  copyPathSync
};

const assert = require('node:assert');
const fs = require('fs-extra');
const os = require('node:os');
const path = require('node:path');
const { copyPath, copyPathSync } = require('../src/index.js');

async function main() {
  const tmpDir = fs.mkdtempSync(path.join(os.tmpdir(), 'fs-extra-copy-test-'));

  try {
    // 1. fs.copy asynchronously copies a single file to a target destination, creating parent directories if needed
    const srcFile = path.join(tmpDir, 'source.txt');
    fs.writeFileSync(srcFile, 'Hello CodeSampleX fs-extra copy', 'utf8');
    const destFile = path.join(tmpDir, 'nested', 'sub', 'dest.txt');
    await copyPath(srcFile, destFile);
    assert.strictEqual(fs.existsSync(destFile), true, 'Destination file must exist');
    assert.strictEqual(fs.readFileSync(destFile, 'utf8'), 'Hello CodeSampleX fs-extra copy', 'Content must match');

    // 2. fs.copy recursively copies an entire directory hierarchy preserving structure and content
    const srcDir = path.join(tmpDir, 'sourceDir');
    fs.mkdirSync(path.join(srcDir, 'subDir'), { recursive: true });
    fs.writeFileSync(path.join(srcDir, 'file1.txt'), 'File 1 Content', 'utf8');
    fs.writeFileSync(path.join(srcDir, 'subDir', 'file2.txt'), 'File 2 Content', 'utf8');

    const destDir = path.join(tmpDir, 'destDir');
    await copyPath(srcDir, destDir);
    assert.strictEqual(fs.existsSync(path.join(destDir, 'file1.txt')), true, 'file1 must exist in dest');
    assert.strictEqual(fs.existsSync(path.join(destDir, 'subDir', 'file2.txt')), true, 'file2 must exist in dest subDir');
    assert.strictEqual(fs.readFileSync(path.join(destDir, 'file1.txt'), 'utf8'), 'File 1 Content');
    assert.strictEqual(fs.readFileSync(path.join(destDir, 'subDir', 'file2.txt'), 'utf8'), 'File 2 Content');

    // 3. fs.copy supports a filter function to selectively copy files and directories
    const filterDestDir = path.join(tmpDir, 'filterDestDir');
    fs.writeFileSync(path.join(srcDir, 'temp.log'), 'Temporary Log Data', 'utf8');
    await copyPath(srcDir, filterDestDir, {
      filter: (src) => !src.endsWith('.log')
    });
    assert.strictEqual(fs.existsSync(path.join(filterDestDir, 'file1.txt')), true, 'file1 should be copied');
    assert.strictEqual(fs.existsSync(path.join(filterDestDir, 'temp.log')), false, 'temp.log should be filtered out');

    // 4. fs.copy rejects with an error when overwrite is false and errorOnExist is true if destination exists
    let overwriteRejected = false;
    try {
      await copyPath(srcFile, destFile, { overwrite: false, errorOnExist: true });
    } catch (err) {
      overwriteRejected = true;
    }
    assert.strictEqual(overwriteRejected, true, 'fs.copy must reject when overwrite is false and destination exists');

    // 5. fs.copySync synchronously copies directory structures and contents
    const syncDestDir = path.join(tmpDir, 'syncDestDir');
    copyPathSync(srcDir, syncDestDir);
    assert.strictEqual(fs.existsSync(path.join(syncDestDir, 'file1.txt')), true, 'Sync copied file1 must exist');
    assert.strictEqual(fs.existsSync(path.join(syncDestDir, 'subDir', 'file2.txt')), true, 'Sync copied file2 must exist');
    assert.strictEqual(fs.readFileSync(path.join(syncDestDir, 'file1.txt'), 'utf8'), 'File 1 Content');

    // 6. fs.copy preserves timestamps when preserveTimestamps option is true
    const timestampSrc = path.join(tmpDir, 'timestampSrc.txt');
    fs.writeFileSync(timestampSrc, 'Timestamp test content', 'utf8');
    const specificDate = new Date('2021-06-15T12:00:00Z');
    fs.utimesSync(timestampSrc, specificDate, specificDate);

    const timestampDest = path.join(tmpDir, 'timestampDest.txt');
    await copyPath(timestampSrc, timestampDest, { preserveTimestamps: true });
    const statSrc = fs.statSync(timestampSrc);
    const statDest = fs.statSync(timestampDest);
    assert.strictEqual(
      Math.floor(statDest.mtimeMs / 1000),
      Math.floor(statSrc.mtimeMs / 1000),
      'Destination mtime must match source mtime when preserveTimestamps is true'
    );

    console.log('Contract tests passed successfully.');
    process.exit(0);
  } finally {
    try {
      fs.removeSync(tmpDir);
    } catch (e) {
      // ignore cleanup errors
    }
  }
}

main().catch((err) => {
  console.error('Contract test failed:', err);
  process.exit(1);
});