Registry / devops / unused-webpack-plugin

unused-webpack-plugin

library2.4.0jsnpmunverified

A webpack plugin that detects and lists unused source files in one or more directories, helping developers identify dead code. Current stable version is 2.4.0, with maintenance through minor releases. It supports webpack 3 and 4 via the hooks API. Key differentiators: simple configuration (directories, exclude patterns, root), optional failure on unused files, and respect for .gitignore (default true). It does not remove files, only reports them, and is focused on development builds. Compared to alternatives like 'webpack-deadcode-plugin', it is more minimal and relies on directories rather than webpack's module graph exclusively.

devops

npm install unused-webpack-plugin

github ↗package ↗

INSTALL

IMPORT

SIG · UNUSED-WEBPACK-PLU

unused-webpack-plugin

devopsjavascriptv2.4.0

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 18–226 runs

build_error

glibc

node 18–226 runs

build_error

Code

Verified usage

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

UnusedWebpackPlugin

✓ const UnusedWebpackPlugin = require('unused-webpack-plugin');

✗ import UnusedWebpackPlugin from 'unused-webpack-plugin';

The package does not ship ESM exports; use CommonJS require.

UnusedWebpackPlugin

✓ const { UnusedWebpackPlugin } = require('unused-webpack-plugin');

✗ const UnusedWebpackPlugin = require('unused-webpack-plugin').UnusedWebpackPlugin;

Default export is an unnamed function; named export does not exist. Avoid destructuring.

UnusedWebpackPlugin

✓ const UnusedWebpackPlugin = require('unused-webpack-plugin');

In TypeScript projects, use a type assertion or skip type checking since no type definitions are bundled.

Shows minimal webpack config with the UnusedWebpackPlugin, scanning 'src' directory, excluding test files, and setting root for relative output.

const path = require('path'); const UnusedWebpackPlugin = require('unused-webpack-plugin'); module.exports = { // webpack configuration plugins: [ new UnusedWebpackPlugin({ // Source directories to scan directories: [path.join(__dirname, 'src')], // Exclude patterns (e.g., test files) exclude: ['*.test.js', '*.spec.js', 'node_modules/**'], // Root directory for relative paths (optional) root: __dirname, // Fail build if unused files found (optional, default false) failOnUnused: false, // Respect .gitignore (default true) useGitIgnore: true, }), ], };

Debug

Known issues

breakingv2.0.0 switched to webpack 4 hooks interface, breaking compatibility with webpack <3.

fix

Upgrade to webpack 4+ or use v1.2.0 for webpack 3 support.

affects: >=2.0.0 <3.0.0

deprecatedPlugin is in maintenance mode; no new features are planned.

fix

Consider alternatives like webpack-deadcode-plugin or unimported.

affects: >=2.0.0

gotchaPlugin does not detect unused exports within files; it only lists files that are never imported.

fix

Use tools like ESLint with no-unused-vars or webpack-deadcode-plugin for unused exports.

affects: *

gotchaDirectories must be absolute paths; relative paths may fail silently.

fix

Always use path.join(__dirname, 'dir') or path.resolve() to define directories.

affects: *

Errors

Common errors & fixes

Error: Cannot find module 'webpack'

webpack is a peer dependency not installed automatically.

fix

Run 'npm install webpack' or ensure webpack is in your devDependencies.

TypeError: UnusedWebpackPlugin is not a constructor

Incorrect import: using destructured import instead of default require.

fix

Use 'const UnusedWebpackPlugin = require('unused-webpack-plugin');' (no destructuring).

No unused files found, but I know there are unused files.

Directories option may not include all relevant directories or exclude patterns are too broad.

fix

Check that 'directories' array includes every source folder and adjust 'exclude' patterns (e.g., remove 'node_modules/**' if already ignored).

Upgrade

Version history

2.4.0latest on npm

Audit

Dependencies

webpackoptionalRequired as a peer dependency; plugin implements webpack compiler hooks.

Agent activity

10 hits · last 30 days

node

Resources

githubhttps://github.com/MatthieuLemoine/unused-webpack-plugin ↗

packagehttps://www.npmjs.com/package/unused-webpack-plugin ↗