karma-rollup

library1.0.1jsnpmunverified

Karma preprocessor that bundles ES2015 modules using Rollup for testing. Version 1.0.1 is the latest stable release (as of 2023+). Designed for use with Karma test runner, it integrates Rollup as a preprocessor to transpile and bundle ES module imports/exports into a single file per test file. Supports Rollup plugins (e.g., Bublé, Babel), custom preprocessors, watch mode with caching, and sourcemaps. Differentiators: lightweight compared to Webpack-based preprocessors, leverages Rollup's tree-shaking and fast bundling. Requires Rollup >=1.0.0 as a peer dependency.

testing

npm install karma-rollup

github ↗package ↗

INSTALL

IMPORT

SIG · KARMA-ROLLUP

karma-rollup

testingjavascriptv1.0.1

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.

rollupPreprocessor

✓ // Configure in karma.conf.js – no import needed

✗ const rollupPreprocessor = require('karma-rollup')

This package is a Karma plugin, not a direct import. It's loaded via Karma's plugin system (plugins: ['karma-*']).

customPreprocessors

✓ // Configure in karma.conf.js – no import needed

✗ const customPreprocessors = require('karma-rollup').customPreprocessors

Custom preprocessors are defined inside karma.conf.js per Karma documentation; not exported by this package.

karma-rollup

✓ npm install karma-rollup --save-dev

✗ npm install karma-rollup

Always install as a dev dependency; it's only used during testing.

Basic Karma configuration using karma-rollup preprocessor with Rollup and Bublé for ES2015 transpilation, outputting in IIFE format with inline sourcemaps.

// karma.conf.js module.exports = function(config) { config.set({ basePath: '', frameworks: ['jasmine'], files: [ 'test/**/*.spec.js' ], plugins: [ 'karma-jasmine', 'karma-chrome-launcher', 'karma-rollup' ], preprocessors: { 'test/**/*.spec.js': ['rollup'] }, rollupPreprocessor: { options: { plugins: [require('rollup-plugin-buble')()], output: { format: 'iife', name: 'MyProject', sourcemap: 'inline' } } }, browsers: ['ChromeHeadless'], reporters: ['progress'], port: 9876, colors: true, logLevel: config.LOG_INFO, autoWatch: true, singleRun: false, concurrency: Infinity }); }

Debug

Known issues

gotcha'input' property is handled automatically by karma-rollup; do not set it in rollupPreprocessor.options.

fix

Remove 'input' from options; the input file is determined by Karma's files and preprocessors.

affects: *

gotchaRollup 2.0+ changed the output format structure; older karma-rollup versions may not support Rollup >=2. Check peer dep: rollup >=1.0.0 (but may work with 2.x).

fix

Update karma-rollup or downgrade Rollup to >=1.0.0 <2.0.0; or test with Rollup 2.0 and adjust output config accordingly.

affects: <=1.0.0

gotchaUsing 'rollupPreprocessor' configuration, not 'rollup' – the key must be exactly 'rollupPreprocessor'.

fix

Set the config key as 'rollupPreprocessor' (not 'rollup') in karma.conf.js.

affects: *

gotchaMissing 'name' in output for 'iife' format will cause Rollup error: 'You must supply output.name for IIFE format'.

fix

Add 'output.name: 'YourProject'' to rollupPreprocessor.options.

affects: *

gotchaIf not using default plugins array, ensure 'karma-rollup' is included in the plugins list (or 'karma-*').

fix

Add 'karma-rollup' to config.plugins or use the wildcard pattern 'karma-*'.

affects: *

Errors

Common errors & fixes

Error: Cannot find module 'karma-rollup'

karma-rollup is not installed or not listed in plugins.

fix

Run 'npm install karma-rollup --save-dev' and ensure plugins includes 'karma-*' or 'karma-rollup'.

RollupError: You must supply output.name for IIFE format

IIFE output format requires a name to avoid global scope collision.

fix

Add property 'output.name: 'MyProject'' to rollupPreprocessor.options.

Error: No provider for "framework:jasmine"! (Resolving: framework:jasmine)

Karma Jasmine framework not installed.

fix

Run 'npm install karma-jasmine --save-dev' and add 'jasmine' to frameworks array.

Upgrade

Version history

1.0.1latest on npm

Audit

Dependencies

rolluprequiredPeer dependency: Rollup >=1.0.0 must be installed separately to function.

karmarequiredPeer dependency: Karma is required to run the preprocessor; typically already installed in test projects.

Agent activity

6 hits · last 30 days

node

Resources

githubhttps://github.com/tao-zeng/karma-rollup ↗

packagehttps://www.npmjs.com/package/karma-rollup ↗