DCX Technology RadarDCX Technology Radar
Adopt

Updated to "adopt".

Assess

Jest is a JavaScript testing framework by facebook to test JavaScript code and React applications / components.

We started using Jest (and watchmen) instead of Karma because it:

  • gives us integrated mocking library
  • gives us integrated support for testing "promises"
  • gives us integrated code coverage report
  • automatically runs tests related to changed files (instead of all tests)
  • gives us parallel test execution
  • gives us snapshot testing for React components

It is easy to set up. And even if you have a running setup with Karma/Chai you can easily replace Karma with Jest. With a small workaround, Chai and Jest test matchers work fine together.