Futuristic test runner 🚀

(🦄, test, runner, testing, ava, concurrent, parallel, fast, tdd, cli-app, cli, jest, mocha, tape, tap, qunit, jasmine, babel, assert, assertion, futuristic, promise, promises, async, function, await, generator, generators, yield, observable, unit, observables, snapshot, expect, typescript, flow)

Critical or Security advisories for 0.22.0

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Changelog for 0.22.0

There's but a few commits in this release, but we've made a big change to how AVA manages its test workers 👩🏼‍🔬👨🏼‍🏭👨🏿‍🚀👨🏻‍⚕️👩🏽‍💼.


Default concurrency

We now cap the number of concurrent workers to the number of CPU cores on your machine. Previously AVA started workers for each test file, so if you had many test files this could actually bring things to a halt. 465fcecc9ae0d3274d4d41d3baaca241d6a40130

You can still customize the concurrency by setting the concurrency option in AVA's package.json configuration, or by passing the --concurrency flag. We've also beefed up input validation on that flag. b6eef5ac30e7839371a420f17060f62f971717aa

Unfortunately this does change how test.only() behaves. AVA can no longer guarantee that normal tests won't run. For now, if you want to use test.only(), you should run tests from just that file. We have an open issue to add an --only flag, which will ensure that AVA runs just the test.only() tests. If you'd like to help us with that please head on over to #1472.


We've also added t.log(), which lets you print a log message contextually alongside the test result, instead of immediately printing it to stdout like console.log. 14f7095d25abc5ffbff7efd7db962eaf5e86daab


  • The WebStorm recipe has been updated with instructions on how to enable the Node.js inspector. d8c21a6b8102bcc11daacba2ea6af6f9b9713959
  • The app setup in the endpoint testing recipe has been fixed e28be05788b50b0ad81c889fa5fb6c4032c4201b
  • The t.notThrows() example has been clarified 57f50072ac37dcc62eeed391c547bf841efb6f85

All changes



💖 Huge thanks to @abouthiroppy, @ydaniv, @nowells, @melisoner2006, @clayzermk1 and @tdeschryver for helping us with this release. We couldn’t have done it without you!

Get involved

We welcome new contributors. AVA is a friendly place to get started in open source. We have a great article on getting started contributing and a comprehensive contributing guide.

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