rollup 4.63.3: rollup

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/rollup@4.63.3
Kind: HOW

Use EXACTLY these public packages and versions:
  - pkg:npm/rollup@4.63.3
Demonstrate these symbols/APIs:
  - rollup

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:sha256:7e991fc4317d8d265a93e08e893f7d4eca7c2767972b8b21e64c3b427b5c975e","contract":["rollup bundles multiple ESM modules into a single chunk","rollup tree-shakes unused exported functions from the bundle","rollup generates CommonJS bundle output when format is cjs","rollup supports in-memory custom plugin hooks for module resolution and loading"],"goal":"verify pkg:npm/rollup@4.63.3","kind":"HOW","packages":["pkg:npm/rollup@4.63.3"],"schemaVersion":1,"symbols":["rollup"]},"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/rollup@4.63.3"],"schemaVersion":1,"subject":"pkg:npm/rollup@4.63.3","symbols":["rollup"],"verifierAdapter":"node-typescript@1"}

{
  "name": "rollup-sample",
  "version": "1.0.0",
  "lockfileVersion": 3,
  "requires": true,
  "packages": {
    "": {
      "name": "rollup-sample",
      "version": "1.0.0",
      "license": "MIT-0",
      "dependencies": {
        "rollup": "4.63.3"
      }
    },
    "node_modules/@napi-rs/lzma-linux-x64-gnu": {
      "version": "1.5.1",
      "resolved": "https://registry.npmjs.org/@napi-rs/lzma-linux-x64-gnu/-/lzma-linux-x64-gnu-1.5.1.tgz",
      "integrity": "sha512-oTXEIha4SsuXdTA4Iyskj0kpdx2yVXdhd75c2v3xGrHFfVMsbhTPZU/nMPL4sWKo4pBHm3aucLaqGlF696dTyQ==",
      "cpu": [
        "x64"
      ],
      "license": "MIT",
      "optional": true,
      "os": [
        "linux"
      ],
      "engines": {
        "node": "^22.20 || ^24.12 || >=25"
      }
    },
    "node_modules/@rollup/rollup-android-arm-eabi": {
      "version": "4.63.3",
      "resolved": "https://registry.npmjs.org/@rollup/rollup-android-arm-eabi/-/rollup-android-arm-eabi-4.63.3.tgz",
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      "cpu": [
        "arm"
      ],
      "license": "MIT",
      "optional": true,
      "os": [
        "android"
      ]
    },
    "node_modules/@rollup/rollup-android-arm64": {
      "version": "4.63.3",
      "resolved": "https://registry.npmjs.org/@rollup/rollup-android-arm64/-/rollup-android-arm64-4.63.3.tgz",
      "integrity": "sha512-uI/ESiaIbbRYAEhzy8PCUWDp1hB0bjAqM06mW9flOoNO4Q8DQpeoREhBR5Hegfl+wpXiguyJv6XSPzEN7OxyHQ==",
      "cpu": [
        "arm64"
      ],
      "license": "MIT",
      "optional": true,
      "os": [
        "android"
      ]
    },
    "node_modules/@rollup/rollup-darwin-arm64": {
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      "resolved": "https://registry.npmjs.org/@rollup/rollup-darwin-arm64/-/rollup-darwin-arm64-4.63.3.tgz",
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      "cpu": [
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      ],
      "license": "MIT",
      "optional": true,
      "os": [
        "darwin"
      ]
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      "resolved": "https://registry.npmjs.org/@rollup/rollup-darwin-x64/-/rollup-darwin-x64-4.63.3.tgz",
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      "license": "MIT",
      "optional": true,
      "os": [
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      "cpu": [
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      "license": "MIT",
      "optional": true,
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      "license": "MIT",
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      "license": "MIT",
      "optional": true,
      "os": [
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      ]
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      "license": "MIT",
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      "license": "MIT",
      "optional": true,
      "os": [
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      "license": "MIT",
      "optional": true,
      "os": [
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      "license": "MIT",
      "optional": true,
      "os": [
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      ]
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    "node_modules/@rollup/rollup-linux-x64-gnu": {
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      "resolved": "https://registry.npmjs.org/@rollup/rollup-linux-x64-gnu/-/rollup-linux-x64-gnu-4.63.3.tgz",
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      "cpu": [
        "x64"
      ],
      "license": "MIT",
      "optional": true,
      "os": [
        "linux"
      ]
    },
    "node_modules/@rollup/rollup-linux-x64-musl": {
      "version": "4.63.3",
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      "cpu": [
        "x64"
      ],
      "license": "MIT",
      "optional": true,
      "os": [
        "linux"
      ]
    },
    "node_modules/@rollup/rollup-openbsd-x64": {
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      "cpu": [
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      ],
      "license": "MIT",
      "optional": true,
      "os": [
        "openbsd"
      ]
    },
    "node_modules/@rollup/rollup-openharmony-arm64": {
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      "license": "MIT",
      "optional": true,
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      "license": "MIT",
      "optional": true,
      "os": [
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      "license": "MIT",
      "optional": true,
      "os": [
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      "license": "MIT",
      "optional": true,
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      "license": "MIT",
      "optional": true,
      "os": [
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      "engines": {
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      "license": "MIT",
      "dependencies": {
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      },
      "bin": {
        "rollup": "dist/bin/rollup"
      },
      "engines": {
        "node": ">=18.0.0",
        "npm": ">=8.0.0"
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      "optionalDependencies": {
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        "@rollup/rollup-android-arm-eabi": "4.63.3",
        "@rollup/rollup-android-arm64": "4.63.3",
        "@rollup/rollup-darwin-arm64": "4.63.3",
        "@rollup/rollup-darwin-x64": "4.63.3",
        "@rollup/rollup-freebsd-arm64": "4.63.3",
        "@rollup/rollup-freebsd-x64": "4.63.3",
        "@rollup/rollup-linux-arm-gnueabihf": "4.63.3",
        "@rollup/rollup-linux-arm-musleabihf": "4.63.3",
        "@rollup/rollup-linux-arm64-gnu": "4.63.3",
        "@rollup/rollup-linux-arm64-musl": "4.63.3",
        "@rollup/rollup-linux-loong64-gnu": "4.63.3",
        "@rollup/rollup-linux-loong64-musl": "4.63.3",
        "@rollup/rollup-linux-ppc64-gnu": "4.63.3",
        "@rollup/rollup-linux-ppc64-musl": "4.63.3",
        "@rollup/rollup-linux-riscv64-gnu": "4.63.3",
        "@rollup/rollup-linux-riscv64-musl": "4.63.3",
        "@rollup/rollup-linux-s390x-gnu": "4.63.3",
        "@rollup/rollup-linux-x64-gnu": "4.63.3",
        "@rollup/rollup-linux-x64-musl": "4.63.3",
        "@rollup/rollup-openbsd-x64": "4.63.3",
        "@rollup/rollup-openharmony-arm64": "4.63.3",
        "@rollup/rollup-win32-arm64-msvc": "4.63.3",
        "@rollup/rollup-win32-ia32-msvc": "4.63.3",
        "@rollup/rollup-win32-x64-gnu": "4.63.3",
        "@rollup/rollup-win32-x64-msvc": "4.63.3",
        "fsevents": "~2.3.2"
      }
    }
  }
}

{
  "name": "rollup-sample",
  "version": "1.0.0",
  "description": "Clean-room sample verifying pkg:npm/rollup@4.63.3",
  "private": true,
  "type": "module",
  "license": "MIT-0",
  "dependencies": {
    "rollup": "4.63.3"
  }
}

{
  "schemaVersion": 1,
  "goal": "verify pkg:npm/rollup@4.63.3",
  "kind": "HOW",
  "packages": [
    "pkg:npm/rollup@4.63.3"
  ],
  "symbols": [
    "rollup"
  ]
}

export function add(a, b) {
  return a + b;
}

export function unused() {
  return 'THIS_SHOULD_BE_TREE_SHAKEN';
}

import { add, unused } from './helper.js';

export const sum = add(10, 32);

import { strict as assert } from 'node:assert';
import path from 'node:path';
import { rollup } from 'rollup';

const inputPath = path.resolve('src/index.js');

// 1. Rollup bundles multiple modules into a single ESM chunk
const esmBundle = await rollup({
  input: inputPath
});

const { output: esmOutput } = await esmBundle.generate({
  format: 'es'
});

assert.equal(esmOutput.length, 1, 'rollup must emit exactly one chunk');
const esmCode = esmOutput[0].code;
assert.ok(esmCode.includes('export { sum }'), 'ESM output must export sum');
assert.ok(esmCode.includes('42') || esmCode.includes('add(10, 32)'), 'ESM output must include evaluated or inlined addition');

// 2. Rollup performs tree-shaking on unused functions
assert.ok(
  !esmCode.includes('THIS_SHOULD_BE_TREE_SHAKEN'),
  'unused export must be tree-shaken and omitted from generated code'
);
await esmBundle.close();

// 3. Rollup generates CommonJS format bundles with expected export syntax
const cjsBundle = await rollup({
  input: inputPath
});

const { output: cjsOutput } = await cjsBundle.generate({
  format: 'cjs'
});

assert.equal(cjsOutput.length, 1, 'rollup must emit exactly one chunk for cjs');
const cjsCode = cjsOutput[0].code;
assert.ok(cjsCode.includes('exports.sum ='), 'CJS output must export sum on exports object');
await cjsBundle.close();

// 4. Rollup supports custom in-memory plugin hooks for module resolution and loading
const virtualBundle = await rollup({
  input: 'virtual-entry',
  plugins: [
    {
      name: 'virtual-module-plugin',
      resolveId(source) {
        if (source === 'virtual-entry') {
          return source;
        }
        return null;
      },
      load(id) {
        if (id === 'virtual-entry') {
          return 'export const greeting = "hello from virtual rollup";';
        }
        return null;
      }
    }
  ]
});

const { output: virtualOutput } = await virtualBundle.generate({
  format: 'es'
});

assert.equal(virtualOutput.length, 1, 'virtual bundle must emit one chunk');
assert.ok(
  virtualOutput[0].code.includes('hello from virtual rollup'),
  'virtual bundle output must contain virtual module code'
);
await virtualBundle.close();

console.log('All rollup contract assertions passed.');