Karma vs uvu

Karma is a JavaScript test runner that starts a web server, connects browsers, runs tests, and reports results to developers. It can watch configured files and rerun tests when they change. Plugins connect frameworks such as Jasmine, Mocha, and QUnit, alongside preprocessors, reporters, and browser launchers. Documented launchers include Chrome, Firefox, Safari, PhantomJS, JSDOM, Opera, Internet Explorer, SauceLabs, and BrowserStack. A browser on another device on the same network, including a phone or tablet, can be captured by visiting the Karma server URL. Karma runs on Node.js and is distributed as an npm package; its installation guide recommends installing it locally in a project. Documentation includes integration guides for Travis CI, Jenkins, and Semaphore CI. The project describes Karma as primarily designed for low-level unit testing and points to Protractor for high-level testing. Karma is free and MIT-licensed, but deprecated: it accepts no new features or general bug fixes. Critical security fixes continue until 12 months after Angular CLI’s Web Test Runner support is marked stable.

uvu is a free, lightweight test runner for Node.js and browser projects. It supports individually executable test files, asynchronous tests that may return Promises, native ES modules and a familiar API. Tests can be grouped into named suites or registered through a simpler test interface, and snapshot testing is supported. Each file is self-contained and can also be run directly with Node.js. The optional CLI collects and executes suites, with options to stop after the first failure, ignore patterns, preload modules, set a working directory and colorize output. When a directory is specified, file matching takes a regular-expression pattern rather than relying on glob patterns. The optional assertion module works in browsers and can be swapped for another library, including Node.js’s native assert. Installation uses `npm install --save-dev uvu`. Package metadata specifies Node.js version `>=8`; the repository identifies the project as MIT licensed and credits Luke Edwards.