rollup-plugin-unassert

0.6.0 verified Mon Apr 27 auth: no javascript maintenance

Rollup plugin to remove assertion calls (e.g., assert, console.assert) from bundles using Unassert. Current stable version: 0.6.0. Low release cadence (last release 2020). Key differentiator: integrates Unassert into Rollup builds, removing debug assertions from production code, improving bundle size and performance. Alternatives like babel-plugin-unassert require Babel; this plugin is Rollup-native.

Common errors

error Error: Cannot find module 'rollup-plugin-unassert' ↓

cause Missing local installation or incorrect import path.

fix

npm install --save-dev rollup-plugin-unassert

error TypeError: unassert is not a function ↓

cause Using named import instead of default import.

fix

Use import unassert from 'rollup-plugin-unassert' (without curly braces).

error ! RollupError: Could not resolve 'unassert' from ... ↓

cause Unassert internal dependency not resolved; Rollup may fail if not installed.

fix

Ensure unassert is installed as a dependency: npm install unassert

Warnings

gotcha The plugin removes assertion calls only in production builds; during development assertions remain. Ensure it is used in production config only. ↓

fix Conditionally add plugin based on process.env.NODE_ENV or similar.

gotcha Sourcemap support: setting sourcemap: false hides assert calls when debugging. Leave as default true to keep sourcemaps accurate. ↓

fix Do not set sourcemap: false unless you understand the debugging tradeoff.

deprecated Package is in maintenance mode; no active development. Consider using a more actively maintained alternative. ↓

fix Evaluate alternatives like babel-plugin-unassert or manual removal.

Install

npm install rollup-plugin-unassert

yarn add rollup-plugin-unassert

pnpm add rollup-plugin-unassert

Imports

unassert

wrong

const unassert = require('rollup-plugin-unassert')

correct

import unassert from 'rollup-plugin-unassert'

ESM-only; CJS require works but may cause issues with Rollup's plugin resolution.

default import

wrong

import { unassert } from 'rollup-plugin-unassert'

correct

import unassert from 'rollup-plugin-unassert'

Default export only; named import does not exist.

TypeScript type (if needed)
```
import type { RollupPluginUnassertOptions } from 'rollup-plugin-unassert'
```
Types are not bundled; you may need to define your own or use @types.

Quickstart

Basic Rollup config with rollup-plugin-unassert to remove assertion calls from build output.

import unassert from 'rollup-plugin-unassert';

export default {
  input: 'src/index.js',
  output: {
    file: 'dist/bundle.js',
    format: 'esm'
  },
  plugins: [
    unassert()
  ]
};