Registry / devops / rollup-plugin-banner2

rollup-plugin-banner2

library1.3.1jsnpmunverified

Rollup plugin to prepend a banner (e.g., license, metadata) before bundled JavaScript code, surviving minification where Rollup's built-in output.banner is stripped by plugins like rollup-plugin-uglify. Version 1.3.1 (stable; maintained as of 2024). Key differentiators from rollup-plugin-banner (unmaintained): supports sourcemaps, per-chunk banners via ChunkInfo, custom formatters (docBlock, docBlockAndGap), and async resolveBanner. Drawbacks vs alternatives: no file path loading, no package.json template injection, no automatic JS comment wrapping. Requires Node >=12.13 and Rollup.

devops

npm install rollup-plugin-banner2

github ↗package ↗

INSTALL

IMPORT

SIG · ROLLUP-PLUGIN-BANN

rollup-plugin-banner2

devopsjavascriptv1.3.1

Install

—

Import

—

Disk

—

Pass rate

0/ 6

Env Coverage0 / 6

glibc

18–22

musl

18–22

Install & Compatibility

Where this runs

tested against v? · npm install

Install × environment matrix

Each cell = how many times install + import succeeded across repeated harness runs. Partial = flaky.
glibc = Debian/Ubuntu slim · musl = Alpine Linux

musl

node 18–223 runs

build_error

glibc

node 18–223 runs

build_error

Code

Verified usage

Verified import paths — ran on the pinned version, not inferred.

banner2

✓ import banner2 from 'rollup-plugin-banner2'

✗ const banner2 = require('rollup-plugin-banner2')

Package is ESM-only; CJS require will fail with ERR_REQUIRE_ESM in Node >=12.

banner2

✓ export default { plugins: [banner2(() => '/* my banner */')] }

✗ export default { plugins: [banner2('/* my banner */')] }

resolveBanner must be a function, not a string literal.

BannerFunction

✓ import type { BannerFunction } from 'rollup-plugin-banner2'

✗ import { BannerFunction } from 'rollup-plugin-banner2'

Type-only import; runtime import will throw TypeError.

Basic Rollup config using banner2 with per-chunk banners and docBlock formatter.

import banner2 from 'rollup-plugin-banner2'; export default { input: 'src/index.js', output: { dir: 'dist', format: 'es' }, plugins: [ banner2( (chunk) => `/** * Bundle: ${chunk.fileName} */ `, { formatter: 'docBlock' } ) ] };

Debug

Known issues

breakingPackage is ESM-only since v1.0. Node <12 incompatible; CJS require() fails.

fix

Use import syntax. Update Node to >=12.13. If legacy CJS required, use dynamic import() or downgrade to rollup-plugin-banner (CJS).

affects: >=1.0

deprecatedThe 'formatter' option only supports 'docBlock' and 'docBlockAndGap'; custom formatters were removed in a prior version.

fix

Use resolveBanner function to implement custom formatting.

affects: >=1.2

gotcharesolveBanner must return a string, stringifiable object, or falsey. Returning undefined or null results in empty banner.

fix

Ensure function always returns something (string, Buffer, etc.) or handle falsey explicitly.

affects: >=1.0

gotchaWhen sourcemaps are enabled (default), banner content is added to sourcemaps; minifiers may still strip banner if not sourcemap-aware.

fix

If banner is stripped by minifier, try disabling sourcemaps (sourcemap: false) or use a dedicated banner plugin designed for minifiers.

affects: >=1.0

Errors

Common errors & fixes

Error [ERR_REQUIRE_ESM]: require() of ES Module /path/to/node_modules/rollup-plugin-banner2/index.js not supported.

Using CommonJS require() with ESM-only package.

fix

Use import statement instead of require().

TypeError: banner2 is not a function

Importing with incorrect syntax or using default import for a named export.

fix

Use import banner2 from 'rollup-plugin-banner2' (correct) or const banner2 = (await import('rollup-plugin-banner2')).default.

Error: The "sourceMap" option is deprecated; use "sourcemap" (all lowercase).

Using incorrect camelCase option name.

fix

Change sourceMap to sourcemap in options object.

Upgrade

Version history

1.3.1latest on npm

Audit

Dependencies

rollupoptionalPeer dependency; plugin is a Rollup plugin and requires Rollup at runtime.

Agent activity

5 hits · last 30 days

node

Resources

githubhttps://github.com/stropho/rollup-plugin-banner2 ↗

packagehttps://www.npmjs.com/package/rollup-plugin-banner2 ↗